Industrial Waste as Raw Material for Producing Synthetic Wollastonite in Russia

Abstract

Abstract-In this paper we present the results of analysis of the scientific and technical literature concerning the ways of obtaining wollastonite from various calcium and silicon-containing technogenic wastes accumulated on the territory of the Russian Federation. We proposed a method for producing autoclave needle-like wollastonite from waste of boric acid (borogipsa) containing both calcium and silicon constituents. The phase composition and morphology of the products autoclaving borogipsa were studied. It is found that the initial product has a crystalline phase of unreacted calcium sulfate anhydrous, tobermorite and xonotlite. After firing at 1000 °C, the amorphous calcium hydrosilicates are converted to a crystalline phase of wollastonite triclinic modification. The effect of firing temperature on phase composition and morphology of the compounds obtained by autoclave treatment were described. It is shown that with increase of the firing temperature up to 1200 °C along with a phase change, the composition variation of the particle morphology occurs. It is found that the processing borogipsa to obtain needle-like wollastonite recommended firing temperature should not exceed 1000 °C.

Use of silicate by-products in water treatment processes and development of eco-friendly self-polishing antifouling coatings

“…As an alternative source of raw materials, the large scale industrial waste containing a large amount of silicon could be used, as well as renewable plant waste from the processing of agricultural products (Singh et al 2020;Goodman 2020). Involvement of huge volumes of waste of agricultural crops of annual plants and waste generated during the technogenic processing of mineral resources into recycling is an urgent task of modern industry and environmental safety (Kumar et al 2016;Yarusova et al 2017).…”