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The effect of the conditions of the acetylation process of raw and activated birch bark on the yield and composition of the products is investigated. The structure of biologically active betulin diacetate (BDA) is confirmed with physicochemical methods. The optimal regimes of the one-step original method for the production of BDA from raw and activated birch bark are established using the experimental and computational techniques.

The bonfire (Cannabis sativa) was delignified with the reaction mixture “acetic acid - hydrogen peroxide - sulfuric acid catalyst - water” at a sulfuric acid concentration of 0.45%, a liquid module of 6, and a temperature of 85 °C. The effect of cooking conditions (hydrogen peroxide concentration and process duration) and mass grinding up to 34 … 36 °SR on the morphological properties of technical cellulose fibers - length, width, degree of inhomogeneity (polydispersity) - has been studied. Hemp fibers are inferior in length to those of spruce wood and wheat straw, but more uniform. The widths of hemp and wood fibers are almost the same. Due to its high strength characteristics, peroxide cellulose from bonfire is suitable for use in composition with other fibrous semi-finished products in the production of mass types of paper and cardboard products.

Hemp fire (Cannabis sativa) was delignified with the reaction mix “acetic acid - hydrogen peroxide - sulfuric acid catalyst - water” under sulfuric acid concentration of 0.45%, liquid module of 6, and temperature of 85 ° C. The cellulose was ground to 34 … 36°SHR and mixed in different ratios in compliance with the simplex-centroid experimental design with bleached sulfate softwood and hardwood pulp. The influence of the mixed composition formulations on the main strength properties of paper castings has been studied. It has been concluded that technical cellulose obtained from hemp fire applying this method, can be used for paper products manufacturing in combination with sulphate cellulose from coniferous and deciduous wood.

Pond-coolers at heat and nuclear power stations are natural-technological systems, so the program of their monitoring should include the effect made by the SRPS (state regional power station) on the pond ecosystem, including thermal discharge of cooling water. The objectives of this study were development and implementation of a monitoring program for the cooling pond of Berezovskaya SRPS-1 on the chemical and biological water quality indicators and identification of patterns of the thermal and hydrochemical regime when operating the progressive power plant (from 1996 to 2015). The quality of the cooling water of the pond-cooler BGRES-1 was studied under full-scale conditions by selecting and analyzing the water samples of the pond in accordance with the principles of complexity, systematic observation, and consistency of timing their conduct with the characteristic hydrological phases. Processing of the obtained array of monitoring data by methods of mathematical statistics makes it possible to identify the main factors affecting the water quality of the pond. The data on water quality obtained during their monitoring and mathematical processing over a long time interval are the scientific basis for forecasting the ecological state of the pond, which is necessary to economically ensure the efficient energy production and safety of water use. Recommendations proposed by these authors, including those partially already implemented, have been to prevent the development of eutrophication processes in the pond-cooler: the construction of a dam that cuts off the main peat massif and cleaning the river banks forming the cooling pond.

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала. An example of the potential for robust control of soluble cellulose production was proposed and illustrated.

Acid prehydrolysis does not impede subsequent peroxide delignification, increases the mass fraction of α-cellulose, and improves the reactivity of cellulose but does not ensure a high degree of modification. Aqueous prehydrolysis is less effective. Cold alkaline modification of coniferous (spruce) prehydrolysis peroxide cellulose is highly effective and increases the mass fraction of α-cellulose to 97.5%. Deciduous wood is delignified and modified more easily than coniferous wood. Deciduous (birch) cellulose with up to 99% mass fraction of α-cellulose can be obtained by peroxide cooking with acid prehydrolysis, finishing, and cold alkaline modification. The process regimes developed allow processing highly modified coniferous and deciduous cellulose with properties as good as sulfate cord cellulose with minimal technogenic environmental pollution.

A micromethod was developed for estimating the reactivity of cellulose to acetylation by monitoring temperature variation in the process.

An environmentally clean peroxide method of manufacturing cellulose was developed as an alternative to the traditional pulping method. Spruce and birch are delignified with hydrogen peroxide in acid medium in the presence of catalysts and the cellulose undergoes bleaching and cold alkali modification. The properties of the cellulose obtained are as good as sulfate cord cellulose.

The possibility of fabricating cotton cellulose from linters with a process scheme which provides for altering the order of the stages of alkaline and acid cooking was investigated. The molecular and process indexes of the cellulose obtained were determined. The possibility of fabricating cotton cellulose with a satisfactory content of α-cellulose, degree of polymerization, and reactivity was demonstrated.