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Прусов, А. Н.; Zheleznov, K. N.; Алексеева, О. В.; Padokhin, V. A.; Rozhkova, O. V.

doi:10.1023/a:1020618211437

Cited by 4 publications

(2 citation statements)

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“…The major obstacle in the development of mechanical methods for the preliminary treatment of lignocellulose is the difficulty of scaling laboratory developments and the transition to industrial equipment (Akhtar, Scott, Swaney, & Shipley, 2000;Masarin et al, 2009). At present, the majority of studies are carried out in the laboratory (Hilgert, Meine, Rinaldi, & Schüth, 2013;Lin et al, 2010) and are aimed at superfine grinding of the raw material (Millett, Effland, & Caulfield, 1979;Silva, Couturier, Berrin, Buléon, & Rouau, 2012), achieving the maximal possible reactivity of cellulose (Alekseeva, Rozhkova, & Prusov, 1997;Prusov, Zheleznov, Alekseeva, Padokhin, & Rozhkova, 2002), which is often disadvantageous from the viewpoint of energy consumption ( When pretreatment plant raw materials, mechanochemical treatment allows one to increase the reactivity of the substances incorporated in the treated materials due to an increase in the specific surface area (including the area suitable for interaction with reagents and enzymes), a decrease in cellulose crystallinity and a general disordering of the supramolecular structure of cell walls.…”

Section: Principles Of the Mechanical And Mechanochemical Methods Amentioning

confidence: 99%

Current achievements in the mechanically pretreated conversion of plant biomass

Bychkov

Podgorbunskikh

Bychkova

et al. 2019

Biotech & Bioengineering

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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.

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Section: Principles Of the Mechanical And Mechanochemical Methods Amentioning

confidence: 99%

Current achievements in the mechanically pretreated conversion of plant biomass

Bychkov

Podgorbunskikh

Bychkova

et al. 2019

Biotech & Bioengineering

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“…and its reactivity in a mixture of organic solvents: methylmorpholine N-oxide monohydrate and dimethyl sulfoxide, was investigated in [42]. Increasing the frequency of the mechanical effect decreased the particle size and electrophoretic mobility and increased the surface charge density and solubility, and decreased the viscosity of the cellulose solutions obtained due to a decrease in its DP, development of microporosity, and an increase in the internal surface area of the polymer as a result of the mechanical effect.…”

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Physicochemical properties of heterogeneous cellulose—solvent systems

Захаров

Прусов

2006

Fibre Chem

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The effect of low-molecular-weight liquids on the physicochemical properties of cellulose was investigated, the mechanical and chemical effects on the structure of cellulose were compared, and the reactivity of cellulose was investigated. The determining role of the system of hydrogen bonds and its structure in the reactivity of cellulose, which can be varied with chemical or mechanical effects, was demonstrated.Cellulose processing technology based on formation of cellulose ethers includes processes that take place or begin in heterogeneous medium. Solid-phase reactions are limited by the ratio of the diffusion rates of the reagents and the chemical reaction of the hydroxyl groups in cellulose. The reactivity of the hydroxyl groups in conducting reactions in the solid phase is determined by thermodynamic and to a significant degree, kinetic factors, i.e., the equilibrium flexibility and segmental mobility of the molecular chain in the solid phase. All of these characteristics are a function of the molecular, supramolecular, and morphological structure of cellulose. The participation of hydroxyl groups in formation of a system of intra-and intermolecular bonds, which greatly determines the physicochemical properties of cellulose, is a very important factor.Solvation processes have a great effect on the equilibrium flexibility and segmental mobility of the molecular chain. Studying the effect of liquid media on polymeric materials will produce information on the features of its structure, in particular, the character and intensity of intermolecular interactions.We analyzed the research on the effect of low-molecular-weight liquids on the physicochemical properties of cellulose and compared the mechanical and chemical effects on the structure and reactivity of cellulose.According to the one-chain model, there are intramolecular hydrogen bonds 03-H...05 and 02-H...06 in natural cellulose, while hydroxymethyl groups are in the tg conformation and all parallel chains are bound by interchain 06-H...03 bonds [1]. The presence of a three-dimensional network of H bonds in cellulose strongly limits the mobility of the units in the cellulose. Rearrangement of hydrogen bonds causes an intentional change in the conformation of the cellulose macromolecules. Destruction of intermolecular bonds in natural cellulose not only under chemical but also under mechanical effects causes the rearrangement.Breaking of hydrogen bonds in natural cellulose as a result of plasticization by low-molecular-weight liquids allows changing the chemical and physicomechanical properties of the polymer. Low-molecular-weight liquids can arbitrarily be divided into three groups: 1 liquids that act only on the amorphous part of cellulose; 2 liquids that act on the amorphous and crystalline parts of cellulose but do not dissolve it; 3 liquids that dissolve cellulose. According to traditional concepts, water belongs to the first group of liquids. Since water is a natural plasticizer of cellulose, great attention has been focused in the literature on its re...

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Powdered diethylaminoethyl cellulose as biomass-derived support for phosphotungstic acid: new solid acidic catalyst for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones

Zhang

Peng

2015

Monatsh Chem

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Cited by 4 publications

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Current achievements in the mechanically pretreated conversion of plant biomass

Current achievements in the mechanically pretreated conversion of plant biomass

Physicochemical properties of heterogeneous cellulose—solvent systems

Powdered diethylaminoethyl cellulose as biomass-derived support for phosphotungstic acid: new solid acidic catalyst for the synthesis of 2,3-dihydroquinazolin-4(1H)-ones

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