Woody biomass contains primarily three macromolecular components, cellulose, hemicellulose, and lignin.  Each has specific yet very different uses and optimization of the use of woody biomass as a renewable resource is directly correlated with the efficiency of the fractionation method used for separation.  Wood component separation is currently more inefficient and environmentally costly than ideal, largely because of chemical bonds between hemicellulose and lignin.  The most troublesome of these cross-links are ether bonds.  The Kravit lab in conjunction with a commercial partner Tethys Research LLC, is developing an alternative to traditional methods of chemical fractionation through the use of enzyme pretreatment.  The Kravit laboratory has created a substrate designed to mimic one of  the ether bonds between lignin and hemicellose (H-L bond) in soft woods.  The substrate is unique in that it fluoresces when the H-L bond is cleaved.  It has been used in bioprospecting experiments to discover an enzyme that may be capable of breaking lignin- hemicellulose bonds in softwoods.  The source of the enzyme is a newly discovered microorganism called B603.  It is now the goal to clone the gene for the enzyme from B603 and test the cloned enzyme on native lignin-hemicelluose complexes.

To test the capabilities of this enzyme, it must be obtained in high enough quantity and in sufficient purity  for testing, yet the cells found to produce this enzyme turn out very little of it.  For this reason, a more efficient and controlled method for optimizing expression has been developed using genetic engineering technology.  First a genetic library from Microbe B603 containing cDNA encoding the hemicellulose-lignin etherase (HLE) was obtained.  mRNA  was prepared from B603 cells that were expressing HLE.  For cost-efficiency, SeqWright, a specialty cloning laboratory, was contracted to actually construct the cDNA library.  The cloning strategy was to make the library in Lambda-ZAP II (Stratagene), a bacteriophage lambda vector which eventually lyses the host cell, allowing the recombinant proteins inside the host cells to access to the cell’s surroundings where the indicating substrate is located.  LambdaZap II’s cloning site is located in a phagemid to simplify subcloning.   The next step is to screen this amplified library using standard procedures.  To do this first XLIBlue, host cells, will be infected with the library in the presence of the indicating substrate and IPTG, a substance that induces the expression of the inserted gene.  The plates will be incubated until plaques appear. Then a hydrophobic membrane will be overlaid to bind and detect the 4MU (a fluorescent compound) that is released from the substrate as a result of any enzyme activity. Fluorescent spots on the membranes will be correlated back to the plaques, and the fluorescent plaques will then be picked and used as starting material for further rounds of subsequent infections until all plaques are fluorescent.  Exassist, a helper phage, will then be used to remove the phagemid from the lambda vector and the phagmid will be transformed into SOLR cells on ampicillin-containing  plates.  The desired phagemid is ampicillin resistant therefore colonies containing it will grow and all cells without it (the rest of the LambdaZapII sequence has no ampicillian resistance) will die. The surviving colonies will be selected, re-grown, and mini-prepped.  Because the enzyme produces auto-fluorescent proteins, it will be important to ensure the fluorescence was not caused by a fluorescent protein as opposed to the cleaved substrate.  To do this, cells will be grown on plates with and without indicating substrate.  If the desired enzyme is present, the first plate should not fluoresce and the second should.  If successful, more of this clone will be produced and purified.  Eventually, the recombinant enzyme will be tested on native lignin-hemicellulos complexes.

2009 REU Interview, July 23, 2009 – Morgan Urello

If you or your class has questions regarding this research or experience, please contact:

mau2107@columbia.edu

Hemicellulose extracts, wood pulp, have been identified as a byproduct from the production of higher value-added products such as ethanol and pulp in an Integrated Forest Bio-refinery (IFBR). In the IFBR process hemicelluloses are partially extracted via an aqueous solution at high pressure and temperature mainly as xylan-oligomers from wood material prior to application of further processes. These oligomers cannot be directly metabolized by microorganisms during the fermentation process used for the production of ethanol. The oligomers must be broken down in a cost effective way from oligomers to monomers. The study will examine if sulfur dioxide (SO2), a gas, is effective as a catalyst for the hydrolysis of hemicellulose oligomers. Since SO2 is a gas it is possible to recycle it through the process and this may reduce operational costs.

The study focuses on the effect of temperature and SO2 concentration on total pressure during the acid hydrolysis process. The study used an oil batch reactor system operation, wireless pressure sensor operation, and bio-refinery concept to study the effect on the total pressure. The study will carry out multiple experiments changing temperature, SO2 concentration and using different extracts. The two techniques to be used are the hot water extract (HWE) and the near neutral extract (NNE). The HWE uses hot water to increase reaction rate. NNE is a technique using sodium acetate to keep the ph level near 7 to reduce the amount of substance needed to neutralize it before the fermentation process.  The temperatures to be examined will be: 100°C, 130°C, 140°C, 150°C, 160°C.  The SO2 concentration to be examined in this study were: 1%, 2% 5% 10%. As an end result, this information will be used to develop new equipment for the acid hydrolysis of xylan to xylose during the fermentation process in the ethanol production process of an IFBR.

2009 REU Interview, July 21, 2009 – Alex Haluska

If you or your class has questions regarding this research or experience, please contact:

aahalusk@syr.edu

Currently the kraft pulping process burns hemicelluloses to recover energy.  However, the hemicellulose can be extracted from pulping process and utilized to produce fuels and other chemicals.  Unfortunately the green liquor extraction process only produces dilute hemicellulose extract that must be concentrated before it can be converted economically into fuels or other chemicals.  Simple evaporation is not suitable for concentration because the resulting concentrations of sodium and acetic acid inhibit the fermentation process.  This research examines the use of tangential flow ultrafiltration for concentrating hemicellulose extracts.  Tangential flow membrane ultrafiltration will allow for the concentration of the hemicellulose without concentrating the salts or acids.  Experiments will be performed on both the extraction and filtration conditions.  The molecular weight distributions of the extracts can then be compared with the filtration system’s performances and modeled for the design of a concentration system.

2009 REU Interview, July 21, 2009 – Rob Jonson

If you or your class has questions regarding this research or experience, please contact:

jonson@ksu.edu

Foliage from the Picea species will be investigated as a potential macro-scale source of shikimic acid.    Shikimic acid is an important reagent in the synthesis of oseltamivir phosphate, or Tamiflu, which is used in the treatment of the H5N1 strain (bird flu) and H1N1 strain (swine flu).  Specific focus will be initially placed upon white pine needles because of the simplicity, low cost, and industrial practicality of the extraction process.  Ultimately, focus will expand to include all sub-species of the Picea species in an effort to simulate a real forest management situation. The overall goal of the project will be to minimize tree waste in an optimized industrial ready process that maximizes yield of shikimic acid at a low cost while maintaining other industrial operations at their current capacity.
Techniques will be based upon micro-scale methods and research previously conducted at the University of Maine.  Modifications will also be enacted to ensure thata safe product results from the extraction process.  Samples will be freshly collected from various species in the surrounding areas of Orono, Maineand then finely ground for investigation.  Whole needles will also be tested to determine the necessity of the grinding process.  Micro-scale extractions will be performed via an accelerated solvent extractor (ASE), and quantification will be analyzed via a liquid chromatographer combined with a mass spectrophotometer (HPLC-MS).  Additionally, UV light and liquid-liquid extractions will be used to isolate specific compounds of interest within thesamples.  Macro-scale techniques will first include soxhlet extraction with water as the solvent.  Other solvents may be tested to optimize the extraction of shikimic acid.  Experiments will then expand to a high temperature circular digester.  A rocking digester may also be tested to compareresults.  Polarity of the compounds in each sample will play a major role in the choice of extraction solvent.

2009 REU Interview, July 21,2009 – Alex Shaffer

If you or your class has questions regarding this research or experience, please contact:

atshaffer@gmail.com

One avenue to the conversion of cellulosic biomass into ethanol is to extract a by-product stream from the wood chips entering a kraft pulp mill. It has been shown that under optimized conditions, aqueous extraction can yield a dilute stream of fermentable wood-derived sugars while still maintaining the pulp yield and quality. In addition to sugars, the extract also contains furfural and acetic acid, which have been shown to inhibit microbial fermentation and can also be sold as commodity chemicals if separated from the extract at sufficient purity.

The aim of this project is to remove the acetic acid from the aqueous wood extract. Triocytylphosphine oxide (TOPO) in a water insoluble solvent (undecane) has already been tested to remove the acid via liquid-liquid extraction. In this work, trioctylamine (TOA) will be used with a co-solvent (octanol). Key investigations include: developing extraction equilibrium data for water/acetic acid versus an organic-amine system, comparing extraction performance on real extracts versus a pure component system, developing distillation equilibrium data for real extracts versus pure components, and recycling amines in both systems.

These characterizations of the extraction and solvent recovery operations lead to the final objective of the project. TOPO costs nearly ten times as much as TOA per gram; therefore, the recyclability and effectiveness of both TOPO and TOA will be compared to determine the preferable extraction technology.  Looking at the economics of the extraction/distillation system will complete the project and provide substantial insight for pulp mills wanting to also extract and market acetic acid.

2009 REU Interview, July 20, 2009 – Audrey Polifka

If you or your class has questions regarding this research or experience, please contact:

apolifka@ksu.edu

Cellulose is an increasingly important part of the materials industry.  It is the most abundant material on Earth and its natural ability for self adhesion has long been recognized. On the nano-scale, microcrystalline and cellulose nanofibrils have been shown to have similar tensile strengths and stiffness as glass fibers.  The introduction of microcrystalline cellulose into polymers such as polypropylene has produced stronger and more thermostable materials than neatplastics.  Fillers such as cellulose nanofibrils are also environmentally and economically favorable in terms of plastic products because they are natural “green” products.

Cellulose nanofibrils are expected to go even further in applications due to their long aspect ratio and relative strength.  Expected uses may include surface strengthening, bio-nanocomposites, food, cosmetics, medical/pharmaceutical, absorbents, emulsion/dispersion and oil recovery applications (Mikael Ankerfors et al, 2007).  Cellulose nanofibrils are currently being used in composites with polylactic acid as microwave safe food packaging.  However, the nano sized fibrils are difficult to analyze due to agglomeration via hydrogen bonding in aqueous solutions.  Agglomeration results in different sized clumps of fibrils in a polymer matrix leading to a loss in the enhancing properties of the cellulose nanofibrils, rendering them less effective as polymer additives.  Therefore we have chosen sodium silicate or “water glass,” as an alternative matrix material, for preparing cellulose nanofibril composites.  Use of an aqueous-based matrix is expected to keep the fibrils separate at lower concentrations due to strong ionic bonding between the fibrils and the sodium silicate.  In the past, water glass has had applications in automotive and metal repair, food preservation, water treatment, fire protection and fireproofing and insulation.  Although water glass is used in many solutions that act as coatings, it is not itself an ideal coating as it becomes very brittle upon the removalof water.  It is known that treating wood with silicates preserves wood from insects, decay and offers some flame-retardant properties as well as some dimensional stability.  However, because of the high hygroscopicity, high pH values, and increased moisture absorption, strength loss of water glass treated wood isfrequently observed.  It is our goal to improve the properties of water glass as a structural material and/or coating by addition of cellulose nanofibrils.
To make a water glass-cellulose nanofibril composite, the sodium silicate matrix may be cured by mild heating to initiate dehydrolysis and condensation reactions between the silicatemolecules.  The cellulose nanofibril suspension will then be added and dispersed into the matrix using a Speed Mixer®.  Other additives are added to increase the strength of the composite.  The composite mixture will be poured into a mold and cured until a testable solid is produced.  The new composite will be tested and analyzed for improvements upon the properties of solidified water glass alone.  Flexural, tensile and impact strength measurements will be made as well as thermo stability measurements using thermogravimetric analysis (TGA).

2009 REU Interview, July 20, 2009 – John Attonito

If you or your class has questions regarding this research or experience, please contact:

jdatt2@gmail.com

Abstract: The increase in public awareness and pressure to discover and use a renewable resource while having an ecologicallyfriendly process is reaching the paper industry.  Many publication grade papers are coated with pigments that need petroleum based binders to obtain a high quality print.  Other uncoated papers are treated with additional chemicals to help improve printing.   My research is focused on using cellulose nanofibers to coat paper.  The process utilizes a draw down coater which evenly distributes the nanofibers.   The nanofibers will be mixed with other materials that add pigment and/or act as a binder. Pigments such as calcium carbonate or kaolin and binders such as starch and polyvinyl alcohol will be investigated. The nanofiber coated sheets will be examined and compared with industrial grade products for print resolution, ink distribution, and other product characteristics.  The nanofibers have a unique ability to capture ink pigments at the surface of the paper allowing for little ink penetration.  Papers will be tested and compared based on the inks absorption or penetration rate and the inks density. The latter is performed using a reflection densitometer, a Bristow wheel and a microscopic video camera used to measure the contact angles to characterize the surface energy. My research is focused on finding an affordable green method to upgrade paper that should allow companies to reduce their use of petroleum products.

2009 REU Interview, July 20, 2009 – Jacqueline Beckvermit

If you or your class has questions regarding this research or experience, please contact:

jcbeckvermi@fortlewis.edu

Life cycle assessment (LCA) is a commonly accepted technique for determining the environmental sustainability of a product or process. The goal of this research is to complete a cradle to gate LCA of wood hemicellulose derived bio-ethanol from a modified Kraft mill that produces pulp and paper using the LCA modeling software Eco-LCA, Open LCA, and commercial SimaPro. The system boundaries of this study may change depending on data availability. An LCA of wood based bio-ethanol has already been completed using SimaPro, but such LCA technique only accounts for green house gas emissions and non-renewable resources. Other LCA programs consider land usage in their evaluation, and end-point impact assessments also exist that incorporate multiple factors.  Eco-LCA and Open LCA are newly developed models that offer a more complete approach to LCA.  Eco-LCA, a free LCA model available to the public, considers ecosystem goods and services, referred to as natural capital, which accounts for the environmental impact of a process on natural goods and services such as water, soil, wood, and grass. Eco-LCA uses an input-output model to assess a system, resulting in a more comprehensive outlook that requires only simple resource input data, rather than specific information about the emissions from individual processes. SimaPro requires setting a boundary for the types of factors that will be included in the LCA and specific emissions data from each individual process, therefore potentially yielding different results than the Eco-LCA evaluation.  The results of Eco-LCA and Open LCA will be compared to the results of SimaPro LCA, particularly in green house gas emissions and net energy consumption. The discrepancies among the three models will be reported to determine the model that reflects better representation of the environmental impacts of bio-ethanol.

2009 REU Interview, July 17, 2009- Rachel Bowman

If you or your class has questions regarding this research or experience, please contact:

rachel.bowman708@wku.edu

Wood chips utilized in a kraft pulp mill are chemically broken down to remove lignin from cellulose and hemicellulose.  Though numerous applications have been found for the later, lignin (approximately 30% of the dry mass of wood) has proven to be more difficult to utilize and for the most part is burnt for fuel to power the mill.  Because it is so underutilized, inexpensive, plentiful and renewable, lignin is attractive as a feedstock for product development.  A proprietary method of converting lignin into nano structured carbon materials has been developed in the Neivandt laboratory.  However, significant room exists for optimization of the process.  Consequently, the present work aims to further the fundamental understanding of the process and to gain greater control over product specifications through modification of process variables.

2009 REU Interview, July 21, 2009 – Alden Earle

If you or your class has questions regarding this research or experience, please contact:

drivenformore@gmail.com

Methods are being developed to convert wood into fuels like heating oil and gasoline that will reduce the dependence of the United States on foreign oil. Wood is a renewable resource and fuels derived from it can reduce the effects of global warming because growth of new wood reabsorbs the carbon emissions produced by burning the fuel.  When wood is heated without air, it forms an oily mixture of chemicals, called “pyrolysis oil”, which is composed of approximately half carbon and half oxygen. The oxygen reduces the energy content of the oil.  To convert pyrolysis oil into high quality fuel it is necessary to design catalysts which will facilitate the efficient removal of oxygen at lower temperatures, thereby upgrading the oil’s energy content.  The precise chemical composition of the raw oil depends on the wood source and pyrolysis processing conditions, while the product quality depends on the upgrading process. The goal of this project is to characterize catalysts in the deoxygenation of the model compound guaiacol over catalysts such as cobalt/molybdenum sulfides in addition to nitrides on carbon and oxide supports, as well as pure oxides.  Although it comprises only a tiny fraction of the mass of pyrolysis oil, guaiacol is representative of many of the lignin-derived compounds.  Comparison of the efficiency and specificity of different catalysts will be accomplished by performing reactions of guaiacol in decalin solvent in a Parr continuous stirred tank batch reactor at hydrogen pressures of 50 bar. Reaction mixture samples will be removed from the reactor at regular intervals and chemical composition will be determined quantitatively with gas chromatography (GC).  Specifically, conversion is the rate of consumption of guaiacol.  Selectivity will be defined as the amount of deoxygenated products produced compared to the less desirable hydrogenation products.  Products will be identified by comparison with standards using GC, and with GC/mass spectrometry or nuclear magnetic resonance as necessary.  The catalysts will be compared based on guaiacol conversion. They will also be compared based on their selectivity toward deoxygenated products such as benzene, and the minimization of hydrogenated products such as cyclohexane.  Also of interest is the composition of the catalyst itself before and after the reaction, which will be determined using X-ray photoelectron spectroscopy.

REU Interview, July 21, 2009 – Nick Dunn

If you or your class has questions regarding this research or experience, please contact:

njhdunn@gmail.com

The purpose of this project is to use woody biomass efficiently by discovering enzymes that break ether bonds between lignin and hemicellulose. Wood has three major macromolecular components: cellulose, hemicelluloses and lignin. It is believed ether bonds between lignin and hemicelluloses are a primary reason for the strength of both hardwoods and softwoods and for the difficulty of fractionating wood into separate streams of cellulose, hemicelluloses and lignin.

There are several advantages having separate streams of cellulose, hemicelluloses and lignin. Cellulose is used for papermaking. Hemicellulose can be depolymerized into its component sugars and the sugars then used in fermentations to produce building blocks for polymers, fine chemicals, chiral chemicals, or biofuels. The remaining lignin stream can be burned for heat and energy or sold for synthesis of aromatic fine chemicals.

2009 REU Interview, July 20, 2009 – Rosie Ochoa

If you or your class has questions regarding this research or experience, please contact:

compgik@yahoo.com

As natural resources have become increasingly valued, there has been a movement in the pulp and paper industry towards a more holistic model of resource use and production.  This includes interest in potentially high value compounds found in the bark and foliage of trees, which is otherwise discarded as waste.  Particular polyphenolic compounds are noted for their role as antioxidants and their ability to mimic the effects of calorie restriction.  Studies have shown it may protect against age-related ailments including Alzheimer’s disease and cancer.  A group of phytosterols—campestrol, stigmasterol, and sitosterol—have also been identified as important in preventing cardiovascular diseases and high cholesterol.

Research will focus on developing an economically and environmentally viable isolation method for obtaining polyphenolic compounds and phytosterols from Piceaspecies and other trees commonly harvested for paper and fiber production.  First of all, species in which polyphenolic compounds and phytosterols have been identified in high concentrations must be further validated by another round of experimental testing.  Because the compounds produced by trees vary according to species, location in the tree,and season, it is critical to take a variety of samples.  Analytical methods to be used for the further study of samples include Gas Chromatography-Mass Spectrometry for qualitative identification of certain polyphenolic compounds and a quantitative measure of phytosterols and several tests of antioxidant ability.

Second, the refinement processes being used in the research setting (accelerated solvent extraction, liquid-liquid extraction) must be scaled-up and adjusted for industrial and commercial applications.  This will include identifying environmentally benign, inexpensive, and simpler extraction methods by choosing solvents appropriately or finding alternative refinement processes.

July 16, 2009 REU Interview – Annemarie Nauert

If you or your class has questions regarding this research or experience, please contact:

aennt7@gmail.com

Cellulose is the most abundant biological compound on the planet, with exceptional physical and chemical properties. Cellulose nanofibers (several nanometers in diameter) possess superior properties, such as increased tensile strength, elasticity and toughness because of their web-like structure. Modern technologies have made it possible to mechanically produce cellulose nanofibers in large quantities from common cellulose feedstocks. With its enhanced quality, natural abundance and non-toxicity, cellulose nanofibers may be the key to manufacturing inexpensive, sustainable, durable and environmentally unobtrusive materials. With packaging materials accounting for approximately 40% of U.S. municipal landfills, such a material would represent a significant advance.

Previous research has shown that incorporating cellulose nanofibers into other polymers improves the physical qualities of the material. In this research project, cellulose nanofibers will be combined with polymers such as polyvinyl alcohol (PVA) and latex to produce a composite whose characteristics will be analyzed. The liquid materials will be mechanically mixed for one hour to ensure thorough dispersion and then sonicated for a further hour to remove any air bubbles. The composites will be made into test strips by heating in a silicone mold and tested for tensile strength and elasticity with an Instron (5562). The effects of adding cross-linking compounds will also be investigated by incorporating them into the materials in various quantities. It is hoped that the addition of these compounds with cellulose nanofibers to known polymers will produce a low-cost material with increased strength, durability and environmental benefits.

REU Interview July 17, 2009 – Jacob Schual-Berke

If you or your class has questions regarding this research or experience, please contact:

jakeschualberke@gmail.com

July 16, 2009 REU Interview: Diego Rosso

If you or your class has questions regarding this research or experience, please contact:

diego.rosso@upr.edu

Abstract:
Substantial amounts of forest biomaterials including knotwood, bark, and foliage are underutilized in the forest products industry. The nature and distribution of extractives in waste biomaterials provide us with a potential source of high-value chemicals, such as trans-resveratrol. Trans-resveratrol (resveratrol), which is the preferred steric form, is an example of a polyphenol. Polyphenols generally have 3 physiological defense functions: as radical scavengers, as biocides, and as metal chelators. Resveratrol is found in various plants and wines, particularly red wines, and exhibits a multitude of favorable bioactivities: antioxidant and anti-inflammatory activities, anti-platelet aggregation effect, anti-atherogenic property, oestrogen-like growth-promoting effect, growth-inhibiting activity, immunomodulation, and chemoprevention. In this project, resveratrol will be extracted from bark waste using accelerated solvent extraction, following which the compound will be isolated using purification methods and quantified using Gas chromatography-mass spectrometry (GCMS) and various forms of High performance liquid chromatography (HPLC). In addition, the antioxidant properties of various secondary metabolites of bark, including flavonoids, stilbenes, and lignans, will be investigated and quantified.

Interview with Melody Rhine on July 14, 2008 (7:01 minutes)

Adviser: Dr. Benjamin

The purpose of this project is to determine the amount and types of logging equipment utilized throughout the state of Maine. This project should provide knowledge about equipment that can be used in biomass energy harvests. Previous studies have used mail surveys of loggers to determine unused logging capacities (Egan et al 2006). Comprehensive knowledge of the amount of various pieces of equipment in operation would be very useful to determine the amount of equipment currently in use that has the potential to harvest biomass for energy purposes. The study will also show if loggers could use current equipment to harvest biomass for this emerging market, or if new equipment will have to be purchased. To accomplish this, a phone survey of insurance agents will be conducted. Results from this survey will establish whether most of the insurance is underwritten by in-state companies. If it is determined that in-state companies hold a majority of the market share, information from these companies will then be used to determine types of equipment that are being insured. Since even used logging equipment is quite expensive, almost all contractors would have a note on their equipment. Due to this fact, little to no logging equipment would be uninsured and the data from the insurance companies should capture 90 percent or better of the equipment. A second survey of logging contractors will be used to determine the logging systems they employ, whether they carry insurance on their equipment, and the amount of fuel that is used and relative efficiencies. In addition to these basic questions several questions will be asked to determine logger perceptions toward biomass harvest and their willingness to engage in this market. Expected findings are that the underwriter insurance companies’ records will provide sound information on the amount of equipment in use. In addition, the survey response rate from logging contractors is expected to be low, but the response rate in the sample should correspond well to the information from the insurance companies. If this is true, it means that information obtained from insurance companies about the logging equipment insured is likely what logging equipment is actually being used. This information can then be used in the future to determine combinations of equipment that could possibly be used in biomass harvests, as well as what equipment, if any, the average logger would need to purchase to break into this market.

Interview with Ian Stone on July 7, 2008 (39:31 minutes)

Abstract:
The research of nanofibers and nanofibrillated cellulose was undertaken by the FBRI team. The Cole/Fort group plans to study the chemical modification of these materials so that functionalized fibers can be produced and effectively incorporated into new polymers and composites. To prevent the hydrophilic behavior of the single chain polymer because of the hydroxyl groups, the cellulose will be chemically modified to decrease its hydrophilicity.
One of the routes of investigation of the cellulose nanofibers and nanofibrillated cellulose functionality is to introduce organosilicon compounds that are notable for their derivatizing and protecting properties and also serve as intermediates in organic synthesis. Particularly, the silylation process is employed, in which alkoxysilanes bind to the cellulose polymer chain and thus eliminate the hydroxyl groups.
Other routes involve functionalization methodologies for the end groups. For example, free aldehyde functional groups at the end of the cellulose chain should undergo, presumably, reductive amination be means of coupling with water soluble poly(ethylene) glycols so the amine groups can be introduced. Reactions with hydrazinobenzoic acid should introduce carboxyl groups that can be further converted into polymers and polyesters.
In this project the methods described by Abdelmouleh et al.1 (2005) will be followed to react several silanes2 with cellulose, which is enzymatically obtained from Whatman #1 filter paper. The resulting modified fibers will be characterized using a variety of techniques such as Inverse GC, optical microscopy, FT-IR. Several silylating reagents will be investigated.

Interview with Tatyana Khamathutova-Tomlin on July 14, 2008 (7:25 minutes)

Jesse Capecelatro, Dr. Peter van Walsum

University of Maine Department of Chemical Engineering, 5737 Jenness Hall, Orono, ME 04469

Abstract

In a joint collaboration to reduce our dependence on petroleum and harvest valuable byproducts in the pulp and paper industry, there is an interest to produce fuels or chemicals from non-food sources. Replacing crude oil with biomass feedstocks has the potential to lower fossil-fuel CO2 emissions that cause a great threat to our planet, as renewable forest material is carbon neutral. The US pulp and paper industry currently processes approximately 108 million tons of wood per year. During paper production only about 70% of the wood is utilized. The solid cellulose fraction of wood is saved while the lignin and a fraction of the hemicellulose components are discarded. This waste material can potentially be converted and sold into valuable products such as ethanol and acetic acid without disturbing the amount of paper being produced.
A pre-extraction process can be implemented to remove the hemicellulose by a green liquor treatment. A secondary hydrolysis step is required to hydrolyze oligomeric sugars into monomeric sugars before fermentation. If this fermentation occurs in an anaerobic environment, ethanol, acetic acid, butanol and acetone are some of the possible metabolic products.
In the case of hardwoods, the most abundant fermentable wood component in the hemicellulose is xylan. Xylan is a polymer of the sugar xylose, and is broken down into xylose through acid or enzyme-catalyzed hydrolysis. Xylose is a relatively difficult sugar to ferment, but some xylose utilizing organisms can be found in nature and several have also been genetically engineered.
Four organisms will be used in this study; Clostridium phytofermentans, which produces primarily ethanol and some acetic acid; Moorella thermoacetica, which produces acetic acid; Thermoanaerobacterium thermosaccharolyticum, which produces ethanol and acetic acid; Clostridium acetobutylicum, which produces acetone, butanol and ethanol.
These microorganisms may have the ability to produce an abundant amount of ethanol and acetic acid from the hemicellulose extract, and some may also do so with little or no need for secondary hydrolysis. If successful, introducing this form of integrated forest bio-refinery (IFBR) to existing mills would help them remain competitive while simultaneously improving today’s fuel crisis.

Interview with Jesse Capecelatro on July 10 2008 (5:23 minutes)

The successful use of biomass energy is dependant upon the public’s willingness to accept a new technology. In Maine, where forestry is an integral part of many northern economies, the amount of media coverage of biomass and bioproducts varies depending on the location of the media. It is possible to effectively measure the change in quantity of articles as well as the content of the articles using content analysis. After an initial analysis of two of Maine’s major newspapers, the Bangor Daily News and the Portland Press Herald, it was found that content relating to forest biomass varied depending on the location of the paper. In this study, newspapers throughout New England will be analyzed using WordStat Content Analysis software over a fixed period of time. After analyzing the newspapers, it is expected that there will be an overall increase in the quantity of articles concerning biomass and bioproducts and that public dialogue over the costs and benefits of harvesting will also increase. After analysis, the quantity and content of the articles will be compared to the location of the media. It is expected that newspapers in communities that have a greater economic dependence on forestry will publish a greater quantity of articles on biomass and bioproducts harvesting. Using content analysis and framing it will be possible to determine if there is a similar difference in public opinion of biomass harvesting depending on the proximity of the community to a forest harvesting site. As the interest in biomass increases, it will be possible to monitor public opinion to help determine forestry management and biomass policies that are best suited for particular locations.

Listen to an interview with Marci on July 9. 2008 (05:09 minutes)

Abstract

The drying of wood to a low moisture content of 4 to 8% is an important process in the manufacture of Oriented Strand Board (OSB) and Oriented Strand Lumber (OSL). Continuous on-line monitoring of the moisture level is practiced in all commercial facilities. This project will utilize three moisture sensors (on-line near Infrared, stand-alone near Infrared, and a rapid heating/scale unit) available in the AEWC OSB pilot line.

Specifically, the student will:

• Conduct a literature review of the principles of near IR (NIR) moisture detection. Literature will be obtained from the library and online sources. Upon completion of reading and reviewing several pieces of literature, I hope to understand the use of NIR devices for moisture content measurement in wood.

• Learn the operation of the three moisture sensor units (Process Sensors Corp. MCT 300-WP and MCT 600, OHaus MB-45 Moisture analyzer). Equipment setup and training will be conducting to familiarize me with the equipment. These three devices are what I’ll mainly be using to conduct my research.

• Conduct a round-robin analysis of wood moisture with the units to determine the accuracy and correlation of the three devices. Statistical analysis will be done to reveal the variability and accuracy of each device when compared to known accurate moisture detection methods (oven-dry method).

• Use the on-line near IR unit in conjunction with the Koch Bros. conveyor strand dryer to monitor moisture loss in Aspen strands. This part of the experiment resembles a set-up that may take place in an OSB mill. The information and knowledge gained during the first part of the research will help me complete this objective.

• Establish relationships between conveyor dryer settings (speed, dryer temperature) and initial strand moisture content on final moisture setting. This will include the collection of time-series data and the presentation of control-chart information. The computer attached to the system, along with other statistical tools, will allow me to establish relationships between conveyor dryer settings. This information will reveal what settings result in maximum efficiency in drying Aspen strands at several different moisture contents.

Time permitting, the developed techniques and protocol will then be used to determine whether the extraction of hemicelluloses from wood strands prior to drying (a separate research activity looking at OSB quality) impacts the drying rate, energy requirement (due to higher wood moisture content after extraction), and accuracy of the near IR units.

As a result of the project, the student will learn about principles of near IR sensors, experimental design, process control charts, data presentation, and drying energy requirements (wood requirements and drying unit requirements).

Interview with Lucas, Zach and Mike on July 17, 2008

Abby Hamilton

Advisor: Dr. Darrell Donahue

Near-infrared spectroscopy (NIRS) has the potential to advance the productivity of the forest bio-refinery process by rapid identification of material components comprising of liquid extract and woody biomass. The potential exists for composition identification via NIRS to be performed as an in-line process control operation. Before this technology is applied to the forest bio-refinery process, a NIR spectral database of solid wood chips and liquid extract solutions must be developed and analyzed. Model liquid extracts with known compositions were generated in the laboratory while wood chips pre- and post-extraction were acquired from a laboratory-scale bio-refinery process. After developing the database from collected extract and wood chip spectra, partial least squares (PLS) techniques were used in combination with selected pretreatments to develop regression models. Three data pretreatments including standard normal variate (SNV), first derivative and second derivative were completed separately and then compared. The best fit models were then validated by comparing them to spectra of other wood chips and actual liquid extracts removed during a laboratory-scale bio-refining process. Pre-extracted wood chip spectra had a greater magnitude of reflectance than the post-extracted wood chip spectra. Significant differences were seen when a water spectrum was subtracted from liquid extract spectra. First derivative models based on known woody biomass components indicate positive validation results. In order to improve these PLS models, a narrower wavelength range will be used to attempt to optimize regression values. A subtraction data pretreatment may be used to remove the water signal from all of the liquid extract spectra. With the improved PLS models, the components of known composition can hopefully be predicted more accurately. These models may also help predict the composition of actual liquid extract to see if the composition is comparable to the model liquid extract composition. The results to date support the potential for advancement in the identification of extract components via NIRS. With further development of the spectral database and with additional improvements of the PLS models, the identification technique could become more practical for use in industry.

Interview with Abby on July, 11, 2007
Abby was mentoring an Old Town High School student at the time of this interview

The Northeast region of the US is heavily endowed with forests and thus has the potential for high yields of forest bioproducts – one of which is cellulosic ethanol. The use of ethanol in gasoline reduces greenhouse gas emissions, energy dependence from oil and, financial payments to petroleum exporting countries. The goal of this research project is to design and test marketing strategies for the integration of cellulosic ethanol and other practical biofuels into the Northeast’s light-duty fuel supply. This information can be used to help gauge the potential market penetration that cellulosic ethanol will have in the Northeast – enabling the estimation of gasoline displacement, potential job creation, and production costs. This will be accomplished by performing an in-depth literary review of possible marketing techniques to employ for cellulosic ethanol, formulating a survey tool to determine consumer awareness and interest in biofuels, and utilizing the survey in a focus group setting. The results will produce crucial insights into the most effective way to promote the purchases of biofuels, and provide necessary information to policymakers on potential standards for certification and labeling of biofuels products.

Listen to an interview with Andrew on July 9. 2008 (06:40 minutes)

Interview with Jim Grundy on July 23 2008 (5:26 minutes)

The purpose of this project is to produce wood plastic composite (wpc) pellets using the Palltruder (agglomeration) and compare them to pellets of an identical mix, made using a hot face palletizing die attached to the Davis Standard Woodtruder. Following the production of the pellets, the next step will be to find the differences, mechanically as well as physically, using a series of tests.

Physical tests include specific gravity determination, and coefficient of thermal expansion testing. For mechanical testing, flexural testing will be done as well as tensile and izod impact tests. These tests will be performed to determine if the premixing of agglomeration has benefits over the mixing during wood-plastics extrusion. The benefits of agglomeration include the production of specifically sized and shaped material as well better reactivity, decreased fire and explosion hazard. The later may occur from airborne dusts of wood flour and many other materials.

WPC agglomeration has some specific benefits which make it desirable over the conventional twin-screw compounding. Specifically it lowers energy costs due to external heating of the material and the removal of moisture and volatiles in the pellets. It is suspected that the results will show some proof of the potential that agglomeration has had among its other applications. The potential which has been seen in these other applications consists of the ability to mix thermally sensitive materials as well as the other previously stated benefits. Since friction is the primary source of heat and primary principal behind the formation of the pellets, it is known that very little electric power will be used compared to the amount of electric power it takes using a twin screw setup in which a reheating of the setup is required. As for the differences in mechanical and physical properties, it is suspected that both formulations should have similar properties.

Interview with Lucas, Zach and Mike on July 17, 2008

Project: Production and Testing of WPCs manufactured from hot water extracted wood
Mentor: Doug Gardner
(207) 581-2846
Doug_gardner@umenfa.maine.edu
Abstract:
The FBRI project has developed a patent pending hot water extraction process for wood to produce a feedstock for chemicals and/or fuels. Currently, the extract from the wood is being investigated as a possible feedstock for acetic acid and ethanol production, the remaining extracted wood can potentially be utilized in traditional product forms, i.e. paper, oriented strand board, particle board. One project to be investigated is the application of extracted wood flour in extruded wood plastic composites. Research on the analysis of hot water extracted wood has shown that surface energy of the extracted wood is increased which may provide better interfacial interactions between the wood and the polymer during extrusion processing. In addition, the surface energy and subsequent adhesive bonding capacity of WPCs manufactured from extracted wood may be improved, thus allowing for improved adhesion in bonded components such as WPC glulam beams and hybrid WPC-FRP composites. In this study extracted wood flour will be prepared in quantities required for WPC processing on the pilot scale. WPCs manufactured from extracted wood, polypropylene and appropriate processing aids (lubricants, coupling agents) will be manufactured along with an unextracted control and evaluated following appropriate ASTM standards for tensile, flexure and impact tests. Adhesive bonding tests following compression shear block testing will also be performed on the extracted WPCs. This experimental program will involve the Pulp and Paper Process Development Center for wood extraction, and the Advanced Engineered Wood Composites Center for extrusion processing, adhesive studies and material property evaluation. The study will be completed as part of a research team with faculty, staff, and other students in the extrusion research group.

Interview with Lucas, Zach and Mike July 17, 2008

Merging Maine’s forest past and forest future (pdf file)

Research Interests

Fundamental chemical engineering aspects of pulp production and forest biomass conversion processes; in particular those of pulping, bleaching, recovery of pulping chemicals, and production of biomaterials and biofuels.

My work is interdisciplinary, and strives to integrate a chemical mechanistic approach with that of transport phenomena, mass balances and an overall process concept.

FBRI Interview: 08/02/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/vanHeiningen.m4a

Bangor Daily News Article 07/26/07

FBRI Research:
The use of near-infrared spectroscopy (NIRS) could maximize the productivity of the forest bio-products process by aiding the separation of output woody biomass. NIRS and chemometric techniques could eventually be used online as a process control tool for the forest bio-product process.

FBRI Interview:  08/02/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Donahue.m4a

Current Research Interests:

Supply Chain Management within Forest Industry

specific focus given to:
- link between forest / stand production and final product quality
- analysis of transportation systems in forest industry
- harvesting system selection

FBRI Interview July 31, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Benjamin.m4a

Research Interest

FBRI Interview, July 30, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Gardner.m4a

Research:

Nanoprobe Design and Optimization for Biological/Materials Applications

Passive and reactive molecular and quantum dot (metallic and semiconductor) nanoprobes, generally referred to as fluors, have shown great promise as localized reporters in a range of in vitro biochemical and materials systems. The individual fluor represents the highest possible spatial resolution for chemical processes within a sample. However, in order to achieve sufficient signal-to-noise for single fluor imaging/spectroscopy in complicated materials and biological systems, where the main source of signal is often from background radiation, nanoprobes must be specifically designed taking into account their intrinsic photophysics as well as any potential influences of the system of interest. A broad range of techniques are being employed with the eventual goal of controlling photophysical processes of fluors such as photo-stability, excited state dynamics (i.e. lifetime and triplet dynamics), conformational fluctuations in absorption and emission properties, and environmental (chemical) sensitivity and specificity.

FBRI Interview July 30, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Mason.m4a

Research Interests:

Our laboratory focuses on the physiology, molecular biology and ecology of wood degrading fungi. We work primarily with the brown rot fungi. These organisms are an important component of nutrient cycling in coniferous forests and are economically significant because of their ability to attack and degrade wood products. Brown rot fungi are also potentially of interest in biotechnological applications including bioremediation and bioproducts design.

On-going Projects:

The laboratory currently has funded projects in the following areas:

• Metal transport and toxicity in the brown rot fungi.
• The production of the enyzmes cellobiose dehydrogenase and benzoquinone reductase by wood inhabiting fungi.Wood modification by brown rot fungi – chemical characterization studies
• Detection and characterization of wood biodegradation using molecular analysis
• Role of fungi in biotransformation and nutrient cycling in the forest ecosystem:

FBRI Interview July 20,2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Jellison.m4a

Hemicelluloses Pre-Extration Modified Pulping

• Improve pulping yield
• Decrease alkali consumption
• Reduce organic & inorganic load to recovery
• Increased delignification rate
• Improve properties of pulp

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Ban.m4a

RESEARCH:

Dr. Bousfield’s research is directed at the application of fluid mechanics and rheology to industrial processes such as paper coating, paper web formation, printing, bubble coalescence, filtration, flotation, and polymeric film coating. Emphasis is placed on the development of simplified models to represent specific processes and the verification of these models with experiments. A number of novel experimental tools have been built to show the important mechanisms of various processes. Several unique areas have emerged in this effort understanding these processes.

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Bousfield.m4a

Specializations and Research Interests:

Outdoor Recreation Policy and Planning:
- Benefits-Based Management
- Social Capital & Trust
- Citizen Participation
- Gateway Communities
Environmental Interpretation and Education

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/JessicaLeahy.m4a

Current Research Interests:

• Composite materials
• Optical methods in experimental mechanics
• Recycled wood/polymer interfacial behavior
• Modeling of structure property relations

Faculty member in the Advanced Engineered Wood Composites Center

FBRI Interview 07/18/07
http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/shaler.m4a

Research: Cellulose Based Substrates for Interfacial Adsorption Studies This project is aimed at the development of cellulose based substrates which may be probed spectroscopically by both linear and non-linear optical techniques. The optimized substrates will be employed to elucidate interfacial adsorption on cellulosic surfaces in systems relevant to the pulp and paper industry.

Picture from UMaine Today 04/04

FBRI Interview 07/18/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/Neivandt.m4a

Their IFPR (Integrated Forest Products Refinery) work focuses on the production of polymers and biofuels from hemicelluloses extracted from wood chips before they are used for pulp production. The rational for the IFPR is twofold. First, the US pulp and paper industry needs new income to remain viable with the emergence of very large and technologically advanced mills in tropical countries which also have advantages in terms of wood and labor cost. Since US mills already have environmental permits and the infrastructure to handle forest biomass material, the integrated production of high value-added biofuels and new biomaterials from waste streams would lead to competitive synergies, new markets and increased product flexibility. Secondly, fossil-fuel CO₂ emissions and foreign fossil fuel dependence must be reduced. Managed forests have enormous untapped potential as a carbon neutral resource for renewable and biodegradable materials.

FBRI Interview 07/18/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/SaraWalton.m4a

Research:
Overall Themes of Our Projects: the ultimate goal of our research is to develop the fundamental chemistry needed to produce new value-added products from wood. To this end, we are participants in the Maine Forest Bioproducts Research Institute, funded by the National Science Foundation. We also want to facilitate the “greening” of the processing of wood into these products and the traditional use: paper. This means we seek to use environmentally benign reagents and processes….

More – http://chemistry.umeche.maine.edu/Fort/Cole-Fort.html

Interview July 16, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/Investigators/FortCole.m4a

Oriented strandboard is a material made out of wood strands and adhesive that can be substituted for plywood. Compared to plywood OSB is much less expensive which makes it a popular alternative in construction projects. However there are some drawbacks associated with OSB. OSB is more absorbent to water and consequently swells more in damp environments. This could present a problem if a constant thickness is absolutely necessary. Once swelled, OSB is much less permeable to water vapor which can cause a mold or fungus problem in confined areas.

A life cycle inventory is essentially a mass and energy balance on a process. Like any process, there are inputs and outputs to the manufacturing of OSB. The mass inputs include wood and adhesive while the energy inputs include the energy required to cut down the trees, to form wood strands, to transport the wood, to make the adhesive, to accomplish the high temperature and pressure necessary to manufacture the OSB, and to burn off volatile organic compounds. The mass outputs include the finished OSB, any unused raw materials, and any waste products (possibly toxic) from the process. The energy outputs take the form of lost heat and changes in internal energy. However, they are not as significant because the energy inputs are the dominant cost.

The software SimaPro LCA will be used to set up the mass and energy balances and create the LCI model. Once the model is created, parameters can be changed in specific processes and comparisons of environmental impacts can be made between productions with different compositions of raw materials; the goal being to find which parameters the negative environmental impacts (emissions, solid waste, energy use, etc.) are most sensitive to, and to propose ways to minimize these parameters in the actual industrial process.

These model outputs can also be inserted into a larger model, such as one for constructing a house. The effects of using OSB can then be compared to those for using plywood (if a model for the use of plywood is available). With the cost and environmental impacts of this substitution readily available, an educated decision between the two products can then be made.

REU Interview 07/17/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/Nate.m4a

One process option is to burn the woody biomass in the presence of a limited amount of oxygen, producing primarily a combination of carbon monoxide and hydrogen. This combination is commonly referred to as syngas. The syngas can then be combined with more hydrogen and polymerized to produce alkanes in a process called Fisher-Tropsch synthesis. These alkanes of various lengths can then be distilled to produce quantities of the desired compounds ranging from ethane to wax.

One strategy to narrow the product distribution is to prepare the FeCo metal catalyst in a nanoporous material. The first step in understanding the effect of pore size in catalysis is to study the conversion of a series of alcohols on porous tungsten oxide materials that have already been synthesized. A microreactor system will be used to measure the conversion of alcohols into alkenes and ethers. The inlet and outlet gas compositions will be measured using gas chromatography-mass spectrometry (GC-MS). The reaction rates on porous WO3 and on non-porous WO3 will be measured for a series of small-to-large alcohol molecules, and the ratio of porous to non-porous rates will be calculated. The goal is to show that the ratio decreases as the size of the molecule increases, therefore demonstrating that the active sites in the pores are not accessible to the larger molecules.

Before carrying out the alcohol/WO3 reactivity experiments the GC/MS microreactor system needs to be set up and calibrated. Tasks include calibrating mass flow controllers, maintaining and tuning the GC-MS, qualifying the performance of the reactant delivery cells, and measuring the reactivity of the inert SiO2 reactor packing material.

REU Interview Notes 07/10/07

Alex Canney REU Interview Notes (pfd file)

Fungi have potential utilization in the processes of bioconversion because of their ability to produce enzymes and other metabolites that can break down lignocellulose into simple organic compounds and inorganic molecules, a process called biodegration. Simple organic compounds such as sugars can then go through the process of fermentation to produce ethanol. By looking at more aggressive fungal species and optimizing soil block assay techniques, more effective ways of breaking down lignocellulose can be identified. My work will focus on exploring the effects of soil characteristics, incubation times and water content of soil block assays on biodegradation rates. Irpex lacteus, Gloeophyllum trabeum, and Pictomyces sanguineus will be used to test decay rates in white pine blocks. I will also be involved in laboratory experiments looking at composite biodegradation and the effect of microbial colonization on cellulose crystallinity.

REU Interview Notes 07/10/07

Stewart Gramlich Interview Notes 07/10/07 (pdf file)

Partial least squares calibration method (PLS), a multivariate calibration method, was used as well as selected pretreatments to create a mathematical model of the spectra. After calibrating the spectra of the solutions created in the laboratory, the calibration was tested by scanning the extracts that were removed from wood chips after the extraction process.

Differences in physical appearance of the wood chip samples, such as the surface color, grain size and thickness must be taken into account. A variation between the treated and untreated wood chips mostly occurred within the 1000-1350nm range. Effects of the viscosity, the amount of liquid scanned and the type of solvent used for the solution were investigated on the liquid extracts prepared in the laboratory. Generally there was a difference in the liquid extract spectra between 1000-1400nm.

Interview 07/11/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/Abby&Andy.m4a

To do this we will employ a bio-chemical amplification technique using enzymes. The process begins with a molecular beacon that will be engineered down to a specific base on the DNA of the sample to ensure selectivity. If there is an exact match, the hairpin shaped DNA that is attached to the inhibitor of the enzyme will uncoil. This will release the inhibitor and allow the enzyme to start a chemical reaction. We will use a lipase to produce H+ ions. These H+ ions will be used to activate an indicator molecule or dye that will show the presence of the specific pathogen.

The current specific research will deal with maximizing the efficiency of detection not just in solution but on bio-active paper as well. The preliminary unit of this efficiency is: Signal photons (dye) / (time x [enzyme]).

To do this we will have to choose the proper dye that will show the best on the paper in the correct pH of the reaction. In addition, since no two enzyme molecules are alike, there is the variable of different enzyme molecules within an ensemble of similar enzymes that can sometimes produce different results. Consequently, we must find what aspects of the single enzyme molecule optimize the amount of signal photons.

Once the enzyme has been selected and characterized at the sub-ensemble level and also the dye indicator system selected, then device geometries that involve bio-active paper loading will be investigated. Specifically, the “on paper” enzyme activity and dye sensitivity will be compared to data obtained from the solution and ensemble measurements.

Finally, after the first two stages, there is further research to be done on creating an H+ permeable membrane to remove the excess H+ from the system so it does not slow down the reaction according to Le Chatelier’s principle by fueling the reverse reaction.

REU Interview 07/11/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/nimesh.m4a

This research will focus specifically on analyzing the effect of acetic acid on the fermentation of hemicellulose by E. coli K011, a recombinant strain of E. coli that is thought to be more resistant to the adverse effects of acetic acid. After growing this recombinant strain of E. coli it will be used to ferment sugars that have been extracted from wood chips. At first, a few fermentations will be done using pure sugars, and later the actual hemicellulose extracts will be used in the fermentations. This research will focus on finding out if fermentation done by this strain of recombinant E. coli is affected by the acetic acid in the same way that naturally occurring E. coli is. The goal will be to determine the extent to which acetic acid inhibits this strain of E. coli. The samples will be analyzed using HPLC (high performance liquid chromatography) to determine the amount of ethanol produced by the E. coli during fermentation and to examine how much of the sugars from the hemicellulose are converted into ethanol. The knowledge gained from this research could help determine the efficiency of using this fermentation process to produce ethanol from hemicellulose.

The inhibition of bacteria by degradation products of hemicellulose poses a problem to the idea of using biomass to produce ethanol. This particular research could help clarify this problem and help determine whether or not wood can become a practical resource for fuel ethanol production.

Brittany Oetter REU Interview 07/10/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/Brittany.m4a

Not only must the process be cheap and efficient, but the fibrils produced must be able to be utilized. To be useful in industry, these fibrils must have high aspect ratios (the ratio of fibril length to diameter). The problem with measuring the fibril’s aspect ratio is that the fibrils often entangle in the pulp-water suspension due to hydrogen bonding between the fibers. Thus, the technique for creating the fibrils must also have a method of separation that is not deleterious to the fibrils themselves. Furthermore, only fibrils of a certain diameter are useful—ideal nanofibrils have diameters less than 100 nanometers.

Many groups have researched this process in a water-based medium, without pre-treating the sample with enzymes. The aim of this project is to determine which enzymes have the greatest effect on nanofibril production, as well as the most effective method of production. The two machines that are used are the Kady mill, which is an industrial mixer and applies an extremely high shear force to the sample in a short period of time, and the homogenizer, which forces the sample through a series of tubes at 45,000 psi and breaks the sample down into smaller pieces, making the sample more uniform. The Kady mill and homogenizer are used in this experiment to break down the larger microfibrils (which have diameters in the micron range) into smaller nanofibrils. The experiment varies how many passes through the homogenizer produce the greatest number of nanofibrils, how long the sample should be put in a Kady mill and how it should be filtered afterward, and so on. There are many different combinations of methods that involve high-shearing forces that can be tested.

My focus in this project will pertain to the use of Atomic Force Microscopy in this research project. I will gain expertise in using the AFM, and analyze different samples given to me. Different methods of sample preparation will be used, i.e. scanning a dry sample vs. scanning the sample in an aqueous solution. My findings will provide support on the nanoscale for observations made through optical and electron microscopes. I will determine which method of production gives the best nanofibrils.

The results of this project could have many different applications. Many people have thought of uses for nanofibrils were they to become readily available. Nanofibrils can be used to strengthen other materials, such as polymers, without altering the overall appearance. They also have potential to be used in the medical field, such as in dressings or drug delivery systems. These are just a few examples of the applications, but there are many more out there, and certainly more to come.

REU Interview 07/11/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/ryan.m4a

The pre-extraction modified pulping process has three main steps. First, the hemicellulose is extracted from the raw wood chips. This step is the extraction step, which is what allows an overall increase in yield. The hemicellulose is set aside for later use. Second, the remaining post-extracted wood chips are made into pulp by cooking with chemicals such as NaOH and NaS (white liquor) at high temperatures around 170 degrees C. The third and final step is adsorption, in which the hemicellulose is redeposited into the pulp mixture. By extracting the hemicellulose before cooking the woods chips to make pulp, a higher overall percent yield is obtained.

The group has successfully created lab size batches of pulp using the new pre-extraction method, but further testing is necessary in regards to the products physical properties. Dr. Ban will be testing the physical properties of the paper made using the pre-extraction process. Because the physical tests will be run on sheets of paper, preparation of 100 grams of product is necessary. Hopefully, the group will be successful in producing 10 to 12 10-gram samples and then concentrating and combining these samples to obtain a larger batch size for use in the physical properties tests. The tests that will be performed include tensile strength, tear strength, burst strength, and fold strength compared against a control sample. Beating, which is blending the pulp to obtain shorter fibers and increase bonding surface area, will also be tested. Tests using different refining times will be performed to determine which beating yields the highest strength paper. A bleaching comparison will also be performed to make sure the bleaching process is not affected by the pre-extraction process.

The experimental analysis of the physical properties testing will allow Dr. Van Heiningen’s group to determine whether this method of pre-extraction can be used to obtain equally viable final products while increasing yield and decreasing chemical consumption in industrial applications.

Interview with Gracson 07/03/07

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/gracson.m4a

In the computer lab, the computer simulation program Autodock will be used to examine how the xylobiose binds to the enzyme. By setting up a 3-D grid across the enzyme, and analyzing the interactions at different points on the enzyme, the location on the enzyme where xylobiose binds, and the best conformation of the xylobiose for this reaction to occur can be found. Additionally, different conformations will be analyzed to see the effects on the enzyme’s ability to catalyze the reaction. This will in turn give a good idea of what must be done in the lab to accomplish the selective cleavage of the hemicellulose bonds., and will reduce the amount of different xylanases that will have to be bought for lab experiments, and lab work done. This research will also help understand the same problems that are being found under the larger scale hemicellulose molecules.

Interview with Andru July 5, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/andru.m4a

Interview July 5, 2007

http://efolio.umeedu.maine.edu/~tvassiliev/FBRI/2007FBRI/jacob.m4a