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A recent mathematical model describing the pretreatment and alkaline hydrolysis of lignocellulosic biomasses in twin screw extruders (TSEs) is used to study the deconstruction and degradation of blue agave bagasse (BAB), an important waste biomass from the Tequila industry, in a laboratory-scale extruder. This pretreatment process using TSEs is technologically important. Experiments using NaOH for the delignification, extraction, and partial hydrolysis of hemicellulose and cellulose were performed. The effects of using different configurations of the screw elements, temperatures, and operational conditions on biopolymer degradation were assessed. NaOH concentration, residence time, and temperature are found to be determining factors in the extraction of cellulose and hemicelluloses. Partial hydrolysis of the carbohydrates is observed at some of the studied conditions. Reasonably good agreement between experimental data and model predictions is observed, which confirms that the key aspects of the actual process are captured well with the model. This modeling frame may be used in the future for the analysis and study (e.g., scaling up) of industrial processes.

et al.. Suitability assessment of a continuous process combining thermo-mechano-chemical and biocatalytic action in a single pilot-scale twin-screw extruder for six different biomass sources. Bioresource Technology, Elsevier, 2016Elsevier, , vol. 211, pp. 146-153. <10.1016Elsevier, /j.biortech.2016 h i g h l i g h t sAdaptation of lignocellulosic biomass deconstruction process on pilot scale extruder. Combination of alkali pretreatment and biocatalytic action in extruder. Validated of the process on six different lignocellulosic biomasses. Keywords:Lignocellulosic biomass Twin-screw extruder Alkaline pre-treatment Enzymatic hydrolysis Bioextrusion a b s t r a c t A process has been validated for the deconstruction of lignocellulose on a pilot scale installation using six types of biomass selected for their sustainability, accessibility, worldwide availability, and differences of chemical composition and physical structure. The process combines thermo-mechano-chemical and bio-catalytic action in a single twin-screw extruder. Three treatment phases were sequentially performed: an alkaline pretreatment, a neutralization step coupled with an extraction-separation phase and a bioextrusion treatment. Alkaline pretreatment destructured the wall polymers after just a few minutes and allowed the initial extraction of 18-54% of the hemicelluloses and 9-41% of the lignin. The bioextrusion step induced the start of enzymatic hydrolysis and increased the proportion of soluble organic matter. Extension of saccharification for 24 h at high consistency (20%) and without the addition of new enzyme resulted in the production of 39-84% of the potential glucose.

The graft polymerization reaction between ethylene carbonate (EC) and scots pine sawdust (SPS) or peat moss (PM) offers a solvent-free approach to the simple and inexpensive aliphatic derivatization of these lignocellulosic fibers. This reaction was studied with liquid or vapor EC phases in three different reactor configurations: batch stirred (BSR), semi-continuous stirred (SSR) and continuous tubular in the gas phase (CVTR). The use of a vapor phase allowed a satisfactory grafting yield and minimal production of non-grafted polyol by-products. The crosslinking agent 4,4'-methylenebis(phenylisocyanate) (MDI) achieved superior characteristics to form shaped tablets resistant to water disaggregation, a high water retention capacity and high compression strength, characteristics that conventional organic supports like PM or PM-polyurethane foam mixtures used in biofiltration of waste gases do not completely possess.