Mechanochemical Methods of Activating Processes of Biomass Pretreatment

This work deals with the fundamental problems of searching for and attaining synergetic effects manifested upon the mechanochemical pretreatment of plant material. Laws relating the intense physicomechanical effects on the raw material during its preprocessing to the deep hydrolytic reactions of hemicelluloses in the bulk of the structural units of plant biomass are established. It was shown earlier on models that mechanical effects are able to dramatically influence the reactivity of macromolecules by changing the hybridization of bonds. To discover similar regularities for plant structures, we performed experiments on the grinding of biomaterials. The best results were obtained in an extruder in the presence of catalysts for polysaccharide hydrolytic cleavage (acids, alkalies, and enzymes). Using birch wood, it was shown that the hydrolytic processes are accelerated by several orders of magnitude in the extruder force fields; the working temperature was considerably reduced (relative to thermohydrolysis) and neither furfural nor any other harmful side product was detected. Our results suggest that the use of mechanochemical methods allows processing time to be reduced by an order and of magnitude along with the formation of side products, testifying to the utility of this technique's practical application.