Current achievements in the mechanically pretreated conversion of plant biomass

Abstract

At present, “mechanochemistry” is synonymous with “grinding,” according to the views of a significant number of scientists and technologists. Often, one comes across the opinion that “the less the particle size, the better.” The cases of considering chemical reactions occurring during pretreatment, as well as considering changes in the ultrastructure of cell walls are extremely rare. Also, the wrong choice of the type of mechanical impact and the equipment used in most cases leads to excessive consumption of electrical energy and reduce economic efficiency. The review presents the currently available published data on mechanically activated processes for the pretreatment of plant materials and shows that when using mechanical treatment, it is necessary to look more closely at the phenomena occurring, rather than reducing everything to the production of fine and ultrafine powders. As a result of mechanical action, active surface radicals can form, hydrothermal chemical processes can occur, and mechanocomposites can form. The role of interphase processes, changes in surface chemistry, related dimensional effects, and the disordering of the crystal structure and amorphization should be taken into account. In addition, the physicochemical insights in mechanical pretreatment make it possible to more efficiently use the energy delivered to the material, and, consequently, increase the economic efficiency of the activation process.

A Brief Overview on Antioxidant Activity Determination of Silver Nanoparticles

“…Pluym et al used conventional spray pyrolysis [ 82 ], Lee and his colleagues synthesized nanoparticles thermal decomposition [ 83 ], or ball milling was successfully used by Baláž [ 84 ]. This methodology, also called mechanochemical synthesis has recently attracted a significant attention of the research world [ 85 , 86 , 87 , 88 , 89 , 90 , 91 ]. Physical methods are useful because of speed and not using toxic chemicals, but on the other hand disadvantages are also there which are previously mentioned [ 80 ].…”

Changes in the Crystallinity Degree of Starch Having Different Types of Crystal Structure after Mechanical Pretreatment

“…Starch-containing biomass, which is often used in food industry, needs to be pretreated using the methods not involving chemical reagents. Mechanical pretreatment of natural plant-derived polymers is known to reduce grain size of a substance, thus increasing its reactivity in the subsequent heterogeneous processes [20][21][22]. Polymers undergo plastic deformation during mechanical pretreatment.…”

Mechanochemical and Size Reduction Machines for Biorefining

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