Kazakhstani scientists have found a way to extract zinc from industrial waste

Specialists at the National Center on Complex Processing of Mineral Raw Materials of the Republic of Kazakhstan have developed a technology for producing zinc and protective coatings from zinc-containing sublimates - a byproduct formed during the electric smelting of refractory polymetallic ores at the Shalkiya deposit. The work was carried out as part of a scientific and technical program funded by the Republic's Industry Committee.

During the study, the scientists determined the optimal parameters for leaching zinc sublimates in sulfuric acid solutions, allowing for the extraction of up to 80% of the metal contained in them. Unlike traditional reactive salts, the sublimates contain 25–30% zinc and can serve as a valuable raw material for producing electrolytes.

The extracted zinc is then separated by electrolysis, producing dense protective coatings. Pilot samples of composite electrochemical coatings have been created using this technology. A zinc-titanium dioxide coating demonstrated corrosion resistance 3.4 times higher than that of conventional zinc. An even more impressive result was demonstrated by a zinc-copper alloy - its corrosion resistance was ten times higher than that of pure zinc or copper coatings.

According to preliminary calculations, the use of sublimates reduces the need for expensive reactive zinc salts by approximately 40%, significantly lowering production costs and simultaneously reducing the accumulation of industrial waste.

Following this work, a process protocol for producing composite coatings from solutions after sulfuric acid leaching was developed. Four patents were obtained for methods of extracting zinc from spent solutions and producing protective coatings.

The implementation of this technology opens up prospects for reducing the cost of protective coatings, decreasing dependence on imported reagents, reducing the volume of industrial waste, and improving the environmental sustainability of metallurgical production. This development demonstrates successful experience in transforming industrial waste into high-tech raw materials for the electrochemical industry.

Source: rusmet.ru