Complex Processing of Adsorbent Used in the Purification of Hydrogen-Containing Gas

The problems of processing spent adsorbents with a high concentration of chemisorbed chlorine-containing compounds for their reuse are studied in this article. The genesis of the phase composition and morphology at all technological stages of thermochemical regeneration of the spent adsorbent - Axstrap-860 by means of alkaline modification with a combined solution of sodium and potassium hydroxides has been tested by diffractometry and elemental analysis. The results show that the formation of a layer with an increased concentration of alkali metals in the form of the corresponding carbonates and NaOH on the surface of the granules and in the volume of sodium and potassium aluminates provides adsorption of HCl, which are slightly inferior to the fresh adsorbent. The conditions for the removal of halogen-containing substances from technogenic raw materials with the subsequent isolation of useful products have been optimized: (1) crystalline NaCl intended for the preparation of electrolyte for electrode boilers and steam generators; (2) a mixture of chlorides and hydroxochlorides of aluminum tested in the process of coagulation purification of turbid natural and waste waters; (3) pseudoboehmite for the production of an adsorbent-desiccant and the synthesis of magnesium-aluminum spinel using the technology of destruction-epitaxial transformation, and a promising carrier for catalysts for steam reforming of hydrocarbons. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

Catalytic neutralization of gas emissions in the manufacture of pharmaceutical preparations

Environmental protection in the Republic of Uzbekistan with a developed chemical, petrochemical, metallurgical and pharmaceutical industries is an important problem of our time. To solve it, a domestic copper-chromite catalyst “Chemex-203” was previously developed, which was operated for a long time in an energy-saving reversible reactor RKR- 10 in the process of catalytic neutralization of ventilation emissions of highly toxic styrene, toluene and acetone vapors on the territory of the “Hobos-TAPO” joint venture in Tashkent. This paper is devoted to solving a two-sided environmental problem - obtaining copper-chromite catalysts using toxic wastes of local industry for thermal catalytic neutralization of gaseous emissions of volatile organic compounds typical of the pharmaceutical and chemical industries. The conducted studies make it possible to 100% replace imported aluminum hydroxide in the composition of the aluminum-titanium carrier for the copper-chromite catalyst for the complete oxidation of toxic emissions with the intermediate product of the processing of spent alumina adsorbent, including gel-like pseudoboehmite. The resulting catalyst is distinguished by good mechanical strength, chemical and thermal stability and allows highly efficient neutralization of combustible toxic substances in the composition of various gas emissions

Catalytic neutralization of gas emissions in the manufacture of pharmaceutical preparations

Environmental protection in the Republic of Uzbekistan with a developed chemical, petrochemical, metallurgical and pharmaceutical industries is an important problem of our time. To solve it, a domestic copper-chromite catalyst “Chemex-203” was previously developed, which was operated for a long time in an energy-saving reversible reactor RKR- 10 in the process of catalytic neutralization of ventilation emissions of highly toxic styrene, toluene and acetone vapors on the territory of the “Hobos-TAPO” joint venture in Tashkent. This paper is devoted to solving a two-sided environmental problem - obtaining copper-chromite catalysts using toxic wastes of local industry for thermal catalytic neutralization of gaseous emissions of volatile organic compounds typical of the pharmaceutical and chemical industries. The conducted studies make it possible to 100% replace imported aluminum hydroxide in the composition of the aluminum-titanium carrier for the copper-chromite catalyst for the complete oxidation of toxic emissions with the intermediate product of the processing of spent alumina adsorbent, including gel-like pseudoboehmite. The resulting catalyst is distinguished by good mechanical strength, chemical and thermal stability and allows highly efficient neutralization of combustible toxic substances in the composition of various gas emissions