| Copper minerals containing arsenic and antimony become more and more important because the high-quality copper minerals alone fail to meet the increasing demand at home and abroad. Chalcopyrite containing tetrahedrite and tennantite is a typical kind of copper kind. But when it is treated, the existence of arsenic and antimony will lead to the worse quality of copper. Besides, arsenide, antimonide and SO2 will pollute the environment. In the paper a new technology for the dearsnization and deantimony from copper concentrate by H2O-air gas mixtures has been investigated.The effects of roasting time and temperature, particle size and atmosphere on the dearsnization and deantimony are discussed. From experimental data, the optical condition is obtained as follows: roasting temperature of 823K, roasting time of 40min, particle size of 3mm and steam flow of 3L/min. The elimination efficiencies of As and Sb under the above condition are over 90% and 80%, respectively.Volatilization rate formula of As and Sb is deduced. With the formula it can beexplained how roasting time and temperature, partial size and atmosphere effect the roasting efficiency.During roasting experiment in steam atmosphere, some air is introduced into the steam. The experiment indicated that dearsenization efficiency becomes lower and deantimony efficiency becomes higher as the air content of the gas mixtures is increased. At the same time the presence of air in the gas mixtures can promote the formation of copper sulfate.In light of the experiment data, the industrial way of dearsenization and deantimony from copper sulfide concentrate is recommended.All experiments showed that the volatilization efficiencies of As and Sb as well as copper sulfatizing for the roasting by steam-air gas mixture are better than those of the conventional roasting process. Comparing to the conventional roasting, the present process has lower operating cost and lower environmental pollution.
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