Obtaining sorbents based on bentonite and wastewater treatment of hydrometallurgical plants

Abstract

Methods of physico-chemical analysis of the composition of industrial wastewater and the use of sorption materials obtained on the basis of compositions of various chemical reagents with local minerals have been developed. The physicochemical and mechanical properties of the newly obtained composite materials have been studied. The composition of bentonite of the Navbakhor mine consists mainly of polygorskite carbonate, the general chemical composition consists of the following clays: Mg2Al2[Si8O20](OH)2·8H2O·CaCO3. Bentonite also contains kaolinite Al4[Si].4O10]·(OH)8, polymorphic modification, polishplate K[AlSi3O8]·Na[AlSi3O8]·Ca[Al2Si2O8], silica SiO2, beidellite (Na, Ca)·Al(Si, Al) present), calcite CaCO3. Wastewater samples from a hydrometallurgical plant were used as an experimental object. It was found that the heat treatment of bentonite clay has practically no significant effect on the mineralogical composition and structure of the sorbents obtained from it, but has a positive effect on the mechanical strength of the granules. It has been established that the optimal firing temperature of bentonite sorbents is 550-800 °C, since at lower firing temperatures sorbent samples do not have sufficient strength limits. The effective effect of modified bentonites as a sorbent in wastewater treatment of “GMZ” has been determined, especially in the case of bentonite containing copper and aluminum oxides.