Ekaterinburg Non-Ferrous Metals Processing Plant, Verkhnyaya Pyshma, Russia:

V. N. Voinov, Leading Research Engineer
K. P. Konik, Head of Refinery Shop
S. V. Lobko, Leading Research Engineer

“EZOCM-ENGINEERING” LLC, Verkhnyaya Pyshma, Russia:

E. A. Kuzas, Engineer, e-mail: e.kuzas@ezocm.ru

Specialists from Ekaterinburg Non-Ferrous Metals Processing Plant developed and introduced the efficient technology of obtaining of rhodium hydrochloric acid, which provides the electrochlorination of rhodium powder in HCl solution. Laboratory investigations defined the most suitable process parameters, including type, frequency and density of current. Industrial realization of the process developed the electrochemical cell, working in completely automated electrolysis complex, used for atomic chlorine generation with application of symmetrical alternating low-frequency current and chlorination of rhodium powder. This technology has the following advantages: simplicity; high automation grade; high production capacity (not less than 200 kg of rhodium per year); low operational and labor costs; high efficiency (yield is not less than 99.6%); minimal ecological risks (chlorine, generated in electrolysis complex, requiring no storage); high quality of finished output (content of any impurity (Pt, Pd, Ir, Fe, Ni, Cu) is not more than 5.10–3%); solution of rhodium acid, suitable for obtaining of other rhodium compounds (chloride, nitrate, sulfate, phosphate, iodide) using classical approaches of hydrometallurgy. This technology can be used by automobile catalysts and jewelry production enterprises, which have no own raw material base, but want their own precursor production for obtaining of autocatalytic compositions and rhodium plating electrolytes from rhodium powder.

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