酸浸法从低品位氧化锌矿及含锌废石制备碱式碳酸锌
Preparation of basic zinc carbonate from low-grade zinc oxide ore and zinc-bearing waste rock by acid leaching
-
摘要: 采用酸浸法从新疆紫金低品位氧化锌矿及含锌废石制备碱式碳酸锌。在磨矿细度为-74μm占30%,液固比2,硫酸用量52kg/t矿,浸出时间2h,终点pH 1.5~2.0,锌浸出率为63%,氧化锌浸出率97%左右;浸出液采用碳酸钙预中和—碳酸钠沉锌工艺回收锌,在预中和终点pH 4.5~5.0、碳酸钠沉锌终点pH 8.0左右,最终获得锌沉淀率为99%,锌品位约50%的碱式碳酸锌产品,该产品可作为生产电锌的原料。Abstract: Sulfuric acid leaching process for Xin-jiang Zijin low grade zinc oxidized ore and waste rock contained zinc was studied to prepare basic zinc carbonate . About 63% of zinc was extracted under the following conditions: grinding size at 30% passing 74 μm, liquid to solid ratio at 2, sulfuric acid dosage with 52 kg per ton ore, final pH of 1.5~2.0 and leaching time for 2h. As high as 99% of zinc in leaching solution was recovered by the process of pre-neutralization using limestone and precipitation reaction using sodium carbonate with the conditions of pre-neutralization at pH 4.5~5.0 and precipitation reaction at pH around 8.0. The zinc grade of basic zinc carbonate could reach 50%, which could be used as raw material for electrolytic zinc production.