硫化铜矿加压预氧化浸出行为研究

Study on Pressure Pre-oxidation Leaching Process of Copper Sulphide Ores

含铜难处理金矿直接氰化浸出率一般较低,氰化物耗量大,需经预氧化浸出除去含铜杂质后再氰化浸出。以硫化铜矿物为研究对象,在添加氯盐的酸性体系中,开展了黄铜矿加温、加压预氧化浸出过程研究。探讨了预氧化温度、氧气压力、起始硫酸用量、起始氯化钠浓度等对黄铜矿中铜、铁浸出的影响行为。通过理论分析、浸出液化学分析以及黄铜矿预氧化浸出渣的X射线衍射测试研究了黄铜矿酸性体系预氧化浸出的反应历程和预氧化浸出渣的成分。结果表明,氧化反应初期,氧气分压、起始硫酸用量、氯化钠用量越大,铜越容易被浸出,而氧化后期氧气压力对铜浸出影响较小。预氧化浸出过程中有Cu9Fe9S16、Cu39S28及黄钠铁矾和草黄铁矾生成,而黄钠铁矾和草黄铁矾为渣中的最终产物。

With the direct cyanidation leaching rate of copper-bearing refractory gold ores is generally low and the cyanide consumption is high, the pre-oxidation leaching is required to remove copper-bearing impurities before cyanidation leaching. Taking copper sulphide mineral as study objects, the studies of chalcopyrite heating and pressure pre-oxidation leaching process were conducted in acid system adding chloride. The effect of pre-oxidation temperature, oxygen pressure, the initial dosage of sulfuric acid and the initial concentration of sodium chiloride on the leaching process of copper and iron in chalcopyrite was discussed. The process of pre-oxidation leaching reaction and the residue components of pre-oxidation leaching in chalcopyrite acid system were investigated by theoretical analysis, chemical analysis of leaching solution and XRD measurements on chalcopyrite pre-oxidation leaching residues. The results show that copper is easily leached with the increase of oxygen partial pressure, initial dosage of sulfuric acid and the dosage of sodium chloride in preliminary stage of oxidation reaction, while the oxygen pressure has a little effect on the copper leaching in later stage of oxidation reaction.Cu9Fe9S16,Cu39S28 and sodium jarosite and carphosiderite formed during pre-oxidation leaching process while sodium jarosite and carphosiderite are the final products of the residues.