Section I Radiochemislr> & radioisolopes production

lable-2 labeling Yield in differentpH

Number of Count in Organic Count in liquid PH Radiochemical Production phase phase purity 1 1452 54895 2 25% 2 7504 45269 4 14% 3 512150 14372 5 78% 4 150509 11164 55 93% 5 554210 10288 6 84% 6 49012 42209 7 54%

UZ0302001 THE STUDY OF POSSIBILITIES OF GOLD AND SOME PRECIOUS METALS EXTRACTION FROM SLAG OF PYROMETALLURGY

Khudaybergenov U., Khodiev Yu., Tajibayev D.Yu.

Institute of Nuclear Physics, Uzbekistan Academy of Science, Tashkent, Uzbekistan

In the given work, some information on gold concentrating possibilities determination as well as extraction of precious metals from slag is presented In order to perform the above- mentioned processes one must grind the (slag) sample Then some quantity of the slag is selected and irradiated in the reactor facility The irradiated and measured sample is solved in nitric acid, hydrochloric acid and acetic acid as well as in ammonia solutions of different concentrations (8,10,24,32,40%) Under the influence of these acids, when the solutions are stirred, the copper and other precious metals are merged into the solutions on 75 or more percents The weight of sample decreases two times Gold stays in the unsolved part of the sample The further step of the process concerns with the gold extraction from the unsolved part of the sample This should be done because the inorganic acid cannot be washed well The unwashed acids decrease the concentration of cyanides When the gold is leached from the gold - containing ores by the sodium cyanide solutions another precious metals merge into the solution along with gold Namely, copper, nickel, cobalt, molybdenum and others Cyanide solution after leach is undergone gold precipitation by the zinc powder During this process the cyanide complexes of gold and precious metals are destructured and precipitate The precipitations containing gold and other metals are melted The solid solutions are separated into heavy fraction, containing gold and other refractory metals The light fraction also contains gold and some precious metals The processing of slag with organic (acetic) acid is almost the same as that for solving of precious, alkaline, alkaline-earth elements This allows one to process the unsolved part of the sample, containing gold, with the sodium cyanide solution, and to extract gold Basing on the mentioned above researches the scheme for gold and precious metal extraction from slag is developed The slag is processed with 15% solution of acetic acid for 10 hours The solution containing gold and other elements is filtered, precipitated and separated Unsolved part is processed by 0 15% solution of sodium cyanide The cyanide solution, containing gold is separated and the gold is precipitated by the powder of zinc

29