Leaching The Valuable Components From Cu-Ni-S-O Mixed Ore By Sulfated Roasting

With the rapid development of economic,the consumption of nickel has experienced a substantial annual growth.Nickel sulfide ore is the main raw material of nickel products.a large amount of nickel sulfide ore is reserved in our country,but unevenly distributed,mostly low grade and complex multi-metal ore.All those reasons make it particularly important to treat nickel sulfide ore economically and effectively.This research is about treating sulfide copper-nickel ore by sulfated roasting-leaching method.According to the property of ore from different places,we came up with different plans.This paper undertook two aspects of experiment,including that leaching valuable metals by oxidizing roasting the raw ore from Xinjiang and leaching valuable metals by sulfated roasting with two stage the raw material mixing sulfuric acid and sulfide copper-nickel ore from Jinchuan.For the first one investigated the effects of roasting factors(including particle size,roasting temperature,roasting time)leaching conditions(solvent,the liquid-solid radio,leaching temperature,leaching time)on Ni,Cu,Fe extraction rate.The reaction mechanism was analyzed through XRD as well as thermodynamic calculation to get the optimum process conditions.The main conclusions are as follows:(1)Solvent with ammonium salt and ammonia restrained the leaching process of Ni2+and Cu2+.(2)The copper is the easiest to be sulfated,the nickel follows,the iron is the most difficult in the experiment.(3)the optimum process conditions were obtained:roasting temperature 600 ?,time 2 hours,the liquid-to-solid mass ratio 6:1,leaching temperature 50?,time 2.5 hours.Under the optimum conditions,the extraction rates of Ni and Cu were 50.49%and 98.06%,while Fe 1.15%.For the second one investigated the effects of particle size,roasting temperature,roasting time on Ni,Cu,Fe,Mg extraction rate under conditions that water leached under 60?,time 2h,the liquid-to-solid mass ratio 6:1.The reaction mechanism was analyzed through XRD as well as thermodynamic calculation to get the optimum process conditions.The main conclusions are as follows:(1)In roasting process stage one,a lot of metal sulfates was generated;In stage two ferric sulfate was decompose.(2)The optimum process conditions were obtained:the mass ratio of sulfuric-to-ore 1.3,roasting temperature 295 ?,roasting time two hours,particle size 124?m.The extraction rates of nickel,copper,magnesium and iron were separately 90.02%,97.54%,86.81%,3.59%.