细菌浸出电解锰废渣中锰的机制研究

Study on the mechanism of bacterial leaching manganese from the electrolytic manganese residue

从电解锰废渣中分离出一株高效浸锰菌,经鉴定为沙雷氏菌(Serratia sp.)。考察了电解锰废渣培养液、MnO2培养液在有菌和无菌条件下的锰浸出情况,以及有菌液和无菌液在加入不同还原剂后的锰浸出情况。结果表明,在初始pH为6.0、固液质量比为1∶10、温度为37℃的浸出条件下,在电解锰废渣培养液中,无菌条件下的锰浸出率远小于有菌条件下的,反应72h后,无菌、有菌条件下的锰浸出率分别为8.03000%、78.67000%;无论在有菌还是无菌条件下,MnO2培养液中的锰浸出率都较低,反应72h后,无菌、有菌条件下的锰浸出率分别为0.00039%、0.04100%;有菌液加入ZnS、FeS、FeSO4、Fe2(SO4)3、CuS还原剂后,反应72h的锰浸出率分别为73.34000%、70.98000%、69.68000%、10.26000%、1.67000%;无菌液中加入4种还原剂(不包括CuS)后的锰浸出率都相当低,反应72h后,锰浸出率相对较高的是FeS和ZnS,均为0.00620%,锰浸出率相对最低的是Fe2(SO4)3,为0.00500%;沙雷氏菌对电解锰废渣中锰的浸出既不是直接氧化浸出作用,也可能不是间接产酸浸出作用,而可能是一种催化还原作用。

A high effective manganese leaching bacterial strain was skimmed from the electrolytic manganese residue, the strain was identified as Serratia sp.. The obtained strain was employed for leaching of manganese from electrolytic manganese residue culture medium and manganese dioxide culture medium, the effect of different reductants on leaching efficiency was investigated. Results showed that the strain could enhanced the manganese leaching from electrolytic manganese residue culture medium, when initial pH was 6.0, solid-liquid ratio was 1 ： 10, temperature was 37 ℃ and leaching for 72 h, the existence of strain increased manganese leaching rate from 8. 030 00% to 78. 670 00%. The manganese leaching from manganese dioxide culture medium was not visible, under the same conditions, the manganese leaching rates were only 0. 000 39%, 0. 041 00% respectively. Adding ZnS, FeS, FeSO4, Fe2 （SO4）3, CuS to bacteria contained manganese dioxide culture medium, manganese leaching rates were increased to 73. 340 00%, 70. 980 00%, 69. 680 00 %, 10. 260 00%, 1. 670 00 %. While, in blank manganese dioxide culture medium, the enhancement of these reductants on manganese leaching was not significant. The mechanism of manganese leaching by Serratia sp. was discussed; it was proved that Serratia sp. played an important catalytic role in the leaching process.