https://faculty.washington.edu/renatab/courses/PSE490/downloads/pretreatment.pdf

Features of promising technologies for pretreatment of lignocellulosic biomass.

Biofuels produced from various lignocellulosic materials, such as wood, agricultural, or forest residues, have the potential to be a valuable substitute for, or complement to, gasoline. Many physicochemical structural and compositional factors hinder the hydrolysis of cellulose present in biomass to sugars and other organic compounds that can later be converted to fuels. The goal of pretreatment is to make the cellulose accessible to hydrolysis for conversion to fuels. Various pretreatment techniques change the physical and chemical structure of the lignocellulosic biomass and improve hydrolysis rates. During the past few years a large number of pretreatment methods have been developed, including alkali treatment, ammonia explosion, and others. Many methods have been shown to result in high sugar yields, above 90% of the theoretical yield for lignocellulosic biomasses such as woods, grasses, corn, and so on. In this review, we discuss the various pretreatment process methods and the recent literature that...

http://ucce.ucdavis.edu/files/datastore/234-1388.pdf

Methods for Pretreatment of Lignocellulosic Biomass for Efficient Hydrolysis and Biofuel Production

Industrial applications of microbial lipases

Trends in bioconversion of lignocellulose: Biofuels, platform chemicals & biorefinery concept

Cellulases and related enzymes in biotechnology

We performed laboratory and process-scale studies with mixtures of cellulase and hemicellulase enzymes for reducing the refining/beating energy requirement of different types of pulp. Those included hardwood kraft pulp, long fiber fraction of bamboo pulp, old corrugated containers (OCC), and mixed pulp containing new double-lined kraft cuttings (NDLKC) and long fiber fraction of bamboo pulp. In the laboratory, the refining energies were reduced by 18%-45% for different pulps with these enzymes.The strength properties of pulps were not affected by enzyme treatment. In the process scale trials, use of one of the enzyme products in the production of high strength extensible sack kraft paper (ESKP) reduced the required refining energy by 25 kWh/metric ton of pulp. It also yielded savings in steam consumption per ton of paper of about 20% from various sections of the machine operation. The mill was able to bypass one double disc refiner (DDR) when the furnish was changed to 60% unbleached bamboo kraft pulp (long fraction) and 40% NDLKC for producing normal ESKP. This reduced the energy requirement by about 54 kWh/metric ton of pulp, with an 8% savings in steam consumption per ton of paper. The mill was able to produce high strength paper having high porosity without sacri ficing other strength properties. Trials with the same enzyme in a mill producing mainly coated white paper showed a reduction in refining energy of about 70 kWh/metric ton of softwood pulp and 30 kWh/metric ton of hardwood pulp. Steam consumption on the paper machine was reduced by approximately 0.5 ton steam/metric ton of paper. By using enzymes, the mill eliminated a refining bottleneck in its softwood line and increased production by 12%. The strength properties of the pulps were not affected. In a mill producing heavy base papers, enzyme use enabled the mill to bypass one 180 kW triple disc refiner (TDR). Pulp strength and other properties were within the specified limits and comparable to those of the control. All these mills have started using enzyme on regular basis.

Use of enzymes for reduction in refining energy - : laboratory studies

Optimization studies for the production of α-amylase using cheese whey medium

Introduction.- Chemistry, Types and Sources of Ethanol.- Production of Bioethanol.- Ethanol Markets.- Characteristics of Fuel Ethanol.- Benefits and Problems with Bioethanol.- Global Production of Bioethanol.- Future of Bioethanol.

Advances in Bioethanol

This study deals with pretreatment of wheat straw with lignin-degrading fungi and its effect on chemical pulping. Ceriporiopsis subvermispora strains, which preferentially attack the lignin, were used for biochemical pulping of bagasse. Treatment of depithed bagasse with different strains of C. subvermispora reduced the kappa number by 10-15% and increased unbleached pulp brightness by 1.1-2.0 ISO points on chemical pulping at the same alkali charge. Bleaching of biopulps at the same chemical charge increased final brightness by 4.7-5.6 ISO points and whiteness by 10.2-11.4 ISO points. Fungal treatment did not result in any adverse effect on the strength properties of pulp.

Pratima Bajpai

Papers

Use of enzymes for reduction in refining energy - : laboratory studies

Optimization studies for the production of α-amylase using cheese whey medium

Advances in Bioethanol

Biochemical Pulping of Bagasse

Improvement of inulinase stability of calcium alginate immobilized Kluyveromyces marxianus cells by treatment with hardening agents