JSC “Ekaterinburg non-ferrous metals processing plant”, Verkhnyaya Pyshma, Russia:
S. V. Lobko, Leading Research Engineer

LLC “Ekaterinburg non-ferrous metals processing plant – Engineering”, Verkhnyaya Pyshma, Russia:
E. A. Kuzas, Engineer, e-mail: e.kuzas@ezocm.ru

Ural Federal University named after the first President of Russia B. N. Yeltsyn, Ekaterinburg, Russia:
S. S. Naboychenko, Professor, Head of a Chair of Non-Ferrous Metals Metallurgy
V. N. Voinov, Head of Laboratory

Intensification of rhodium powder and panning platinum electrochlorination offers the bulk current lead usage. Electrochlorination with bulk current lead means the usage of conductive material particles as additional current lead clusters. Activated coal is loaded in electrochemical cell together with raw materials. Coal particles, contacting with main current lead surface, form the bulk current lead, which contributes the increasing of contact probability and charge transfer to raw material particles, amount of atomic chlorine release centers and raw material component dissolution velocity. During the electrochlorination of nitrogen industry enterprise slimes, extraction of Pt, Pd and Rh in solution with density of low-frequency alternating symmetrical current (1 Hz) 58.1 A per 1 kg of loaded slimes reaches 41%, 56% and 24%, respectively. Total current yield of Pt, Pd and Rh is 3.5%, and total concentration of these metals in solution is 28.54 g/dm³. During the electrochlorination of platinum-rhodium slimes, velocity of Rh dissolution is the highest (2.21 %/h) using alternating asymmetrical current with relation of anode and cathode cycle time of 2 min/min. Anode current density of 250 A per 1 kg of loaded slimes show 2.27% of Rh current yield, and 1.06 g/dm³ of Rh concentration in solution. Bulk current lead insufficiently increases the velocity of transfer of noble metals in solution during the electrochlorination of secondary raw materials. Noble metal dissolution velocity can be increased by enlarging the anode current density and activated coal loading. We are planning to carry out the investigations in industrial electrochlorinator.

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