核桃壳还原浸出软锰矿的动力学

Reductive Leaching Kinetics of Pyrolusite with Walnut Shell

探究以核桃壳为还原剂硫酸浸出氧化锰矿过程的动力学。考察了搅拌速度、反应温度、硫酸浓度、反应时间以及核桃壳用量对锰浸出率的影响。结果表明,锰的浸出率随着搅拌速度、硫酸浓度、核桃壳用量的增大和温度的升高而增大。浸出前60min浸出率的增长速度较快。在反应温度为369K、硫酸浓度3.5mol/L、核桃壳加入量40g/L、反应时间2.5h、转速200r/min时,锰浸出率达93.18%。浸出过程属于化学反应控制,对应的活化能为45.5kJ/mol,硫酸浓度和核桃壳用量的反应级数分别为0.897、0.2。

Leaching kinetics of pyrolusite was investigated with walnut shell as reductant in sulfuric acid solution.Effects of stirring rate,leaching temperature,concentration of sulfuric acid solution,and dosage of walnut shell on leaching rate of Mn were discussed.The results show that leaching rate of Mn rises with increase of stirring rate,leaching temperature,concentration of sulfuric acid solution,and dosage of walnut shell.Leaching rate of Mn rises rapidly in the first 60 min.Leaching rate of Mn is 93.18% under the conditions including leaching temperature of 369 K,concentration of sulfuric acid solution of 3.5 mol/L,dosage of walnut shell of 40 g/L,leaching time of 2.5 h,and stirring speed of 200 r/min.The leaching process is controlled by interfacial chemical reaction with apparent activation energy of 45.5 kJ/mol.Apparent reaction order of concentration of sulfuric acid and dosage of walnut shell is 0.897 and 0.2 respectively.