Застосування кислих розчинів тіосечовини в процесах хімічної й електрохімічної обробки поверхні срібла і його сплаву 925°

Abstract

The process of chemical cleaning of the surface of silver and its alloy 925° in a solution based on thiourea, sulfamic acid and surfactants is investigated. The composition of the solution and the conditions for its use are proposed. The product does not contain toxic and aggressive components and provides high quality cleaning of the tarnished surface to a shine. For electrochemical polishing of silver and its alloy 925°, electrolytes based on thiourea, citric acid and ethylene glycol are proposed. The use of low concentrations of components and stationary electrolysis at low operating temperatures and current densities ensures high quality of silver surface treatment, minimal loss of precious metal, ease of technology implementation, high energy efficiency and environmental safety of the process. The expediency of using acid solutions of thiourea in the surface treatment of silver products for the jewellery industry and other types of production is substantiated.