Numerical simulations of various reactors for the production of xylose from hardwood hemicellulose by dilute sulfuric acid hydrolysis have been developed to analyze the effects on reactor performance of heat and mass transfer as well as reaction kinetics. An economic objective function representing the incremental cost of producing a 10% xylose solution for fermentation to ethanol was calculate...

1. The extracellular enzymes present in the culture filtrates of Coniophora cerebella grown on various carbohydrate carbon sources were investigated. Enzymes that degraded cellulose derivatives, hemicellulose fractions, starch, laminarin, pectin and several oligosaccharides were detected. 2. All the polysaccharide-degrading activities were adaptive except for that acting on laminarin. 3. The cu...

Pretreatment of biomass is one the most challenging steps in process second-generation (2G) ethanol and biochemical production. Dilute acid pretreatment a widely adapted convenient method to recover pentose (C5) as well hexose (C6) sugars due its featured solubilization hemicellulose cellulose before after enzymatic saccharification, respectively. In present study, dilute sulfuric (H2SO4) sugar...

We have observed large pores in the membrane of giant vesicles in an aqueous medium. The lifetime of the pores can reach 2 min and their size (a few micrometers) enables their visualization by fluorescence microscopy. These pores are obtained thanks to a destabilization of the membrane due to the synergistic action of a cone-shaped and nitrobenzodiazole (NBD) labeled phospholipid illuminated in...

Bile salts are essential for phospholipid secretion into the bile. To study the relevance of the structure of phospholipids for their interaction with bile salts, we used spin-labeled or fluorescent phospholipid analogues of different head groups and acyl chain length. Those analogues form micelles in aqueous suspension. Their solubilization by bile salts resulting in the formation of mixed mic...

To investigate the effects on moisture sorption behavior of wood caused by the removal of chemical components, Populus euramericana flour (40 to 60 mesh) was divided into four groups: untreated, extractives removed, hemicellulose removed, and matrix removed. The samples at the fiber saturation point and under oven-dried conditions were separately exposed to relative humidities of 11%, 45%, and ...

The uncatalyzed hydrolysis and removal of xylan from corn stover is markedly enhanced when operation is changed from batch to continuous flowthrough conditions, and the increase in hemicellulose removal with flow rate is inconsistent with predictions by widely used first-order kinetic models. Mass transfer or other physical effects could influence the hydrolysis rate, and two models reported in...