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Forest biomass represents 25-30 % of the annual biomass available in the USA for conversion into bio-based fuels, bio-based chemicals, and bioproducts in general. The USDA Forest Service Research and Development (R&D) has been focused on producing products from forest biomass since its inception in 1905, with direct combustion, solid sawn lumber, pulp and paper, ethanol as fuel, and silvichemicals all among the mission areas of product research and development. The renewed national interest in biomass conversion to fuels and chemicals is supportive of the most critical need of USDA Forest Service R&D, uses for small-diameter trees and other forest biomass that needs to be removed in the fuel mitigation-fire suppression and forest restoration work of the USDA Forest Service. This paper will summarize the recent USDA Forest Service research on direct combustion, fuel pellets, and conversion of forest biomass to ethanol, both as stand-alone biorefinery processes and as an addition to the traditional wood pulping process. [ABSTRACT FROM AUTHOR]

Results from a study of the influence of macromonomer (MM) composition on the properties of high-biomass content adhesive polymers are reported. Pressure-sensitive adhesives (PSAs) are synthesized through miniemulsion polymerization of n-butyl acrylate, vinyl acetate, and methacrylic acid with lactide-containing MMs. The MMs are generated from bulk ring-opening polymerizations of lactide and ϵ-caprolactone with 2-hydroxyethyl methacrylate. Both meso-lactide and L-lactide were used to produce MMs of various chain lengths and compositions. It was found that properties of generated polymers show a strong dependency both on the content and type of lactide utilized. Standard adhesive tests run on the PSAs demonstrate that MM composition can be used to provide significant control over perfromance properties. [ABSTRACT FROM AUTHOR]

Fast-growing biomass, such as bamboo, has the potential to serve an important future role in the pulp and paper industry with potential to both lower resource costs and improve a product's sustainability. Moso bamboo is particularly interesting due to its fast growth and size, which allows it to be handled and chipped similarly to wood resources. In this study, we will share results of the chip preparation, kraft cooking, and ECF bleaching of this bamboo species and compare its pulpability, bleachability, and physical properties to a fast growing hybrid poplar tree. Results indicate that the bamboo chips cooked and bleached similarly to the poplar hardwood, allowing for co-cooking. The resulting pulps had superior tensile properties at low refining, but did have higher fines that lowered drainability as measured by Canadian Standard Freeness. The bamboo fiber morphology was also measured, indicating the fiber to have length weighted average fiber lengths and coarseness values to be greater than the poplar wood studied, which should allow this material to be used in many paper grades. [ABSTRACT FROM AUTHOR]

Abstract: Building on our laboratory-scale optimization, oxalic acid was used to pretreat corncobs on the pilot-scale. The hydrolysate obtained after washing the pretreated biomass contained 32.55g/l of xylose, 2.74g/l of glucose and low concentrations of inhibitors. Ethanol production, using Scheffersomyces stipitis, from this hydrolysate was 10.3g/l, which approached the predicted value of 11.9g/l. Diafiltration using a membrane system effectively reduced acetic acid in the hydrolysate, which increased the fermentation rate. The hemicellulose content of the recovered solids decreased from 27.86% before pretreatment to only 6.76% after pretreatment. Most of the cellulose remained in the pretreated biomass. The highest ethanol production after simultaneous saccharification and fermentation (SSF) of washed biomass with S. stipitis was 21.1g/l. [Copyright &y& Elsevier]

We designed, constructed, and tested a new device that can measure the rheological properties of lignocellulosic biomass slurries with high solids concentrations (>25%) containing large particles (>10 mm), and that can operate at high temperatures (>230 °C), high pressures (>2.8 MPa), and low pH (<1.0). Rheological properties measured with this Lignocellulosic Biomass Rheometer (LCBR) are consistent with those measured with another instrument. Biomass samples investigated are yield stress materials, consistent with previous reports. For modest temperatures, the viscosity decreases reversibly with increasing temperature. When the biomass is exposed to sufficiently high temperature and low pH, we observe an irreversible decrease in apparent viscosity, consistent with that expected as hydrolysis reactions reduce the concentration of insoluble solids. [ABSTRACT FROM AUTHOR]

n-Butyl acrylate and other acrylic monomerswerecopolymerized with an acrylated macromonomer to produce polymers forpressure-sensitive adhesive (PSA) applications. Macromonomers weregenerated through the ring-opening copolymerization of l-lactideand ε-caprolactone with 2-hydroxyethyl methacrylate (HEMA) atan average molar composition of 5:4:1, respectively. Conversion inthe mini-emulsion polymerization was followed using Raman spectroscopyand was nearly complete within 2 h. Testing of these adhesive polymersindicates that performance properties meet or exceed those of commercialwater-based acrylic PSAs. [ABSTRACT FROM AUTHOR]