锌氧压渣中铁复相强化溶出规律及浸出动力学

Enhanced Leaching of Complex Phase of Iron from Residue of Zinc Pressure Leaching and Its Dissolution Kinetics

在锌冶炼的氧压浸出工艺中,由于铁复杂相的存在,使得铁浸出率不高,导致锌氧压浸出渣中仍存在一定量铁资源未能有效回收。以广东某冶炼厂锌氧压渣为研究对象,首先进行详细的工艺矿物学研究,然后采用硫酸化焙烧-溶液浸出的方法对锌氧压渣中的铁复相进行强化分解及高效溶出。得到了较优的试验条件为:焙烧温度300℃、酸渣质量比0.4、焙烧时间2.0 h、浸出时间1.0 h、浸出温度80℃,液固比L/S=5/1,此时铁浸出率为83.31%,锌浸出率达到97.06%。最后,对铁复相的溶液浸出动力学进行了研究,得到了浸出反应的表观活化能为23.18 kJ/mol,并建立了半经验动力学方程。

Leaching rate of iron is in a low level due to existence of complex phase of iron during zinc pressure leaching.There are still some amount of iron in residue of zinc pressure leaching.Taking the residue from Guangdong province as research object,mineral liberation analysis is carried out at first Then,sulfuric roasting combined with solution leaching was proposed to enhance decomposition and dissolution of complex phase of iron.Leaching rate of Fe and Zn is 83.31 % and 97.06% respectively under the optimum conditions including temperature of 300℃,mass ratio of H2 SO4 to residue of 0.4,roasting time of 2.0 h,leaching time of 1.0 h,and leaching temperature of 80℃,and L/S=5/1.Finally,leaching kinetics of roasting residue is successfully modeled by chemical reaction model with apparent activity energy of 23.18 kJ/mol,and semiempirical kinetics equation is obtained.