碳酸钠和氯化钙对软锰矿阳离子浮选中方解石的抑制作用

摘要

In the cationic flotation of pyrolusite using dodecyl ammine (DDA),the depressive effect of sodium carbonate and calcium chloride on the calcite mineral was investigated systematically through flotation experiments,FTIR analysis,contact angle measurements and zeta potential tests.The microflotation experiments showed that both depressant agents decrease the flotation recovery of calcite significantly.In addition,sodium carbonate acts as activator agent for pyrolusite,and increases its floatability.The flotation experiments and contact angle measurements indicated that the selective depression effect of sodium carbonate on the calcite mineral is more than that of calcium chloride.As evidenced by zeta potential and FT-IR analysis,sodium carbonate decreases the negative charges on the surface of calcite mineral and subsequently reduces the adsorption of DDA collector through electrostatic forces.At a pH of 7.5,using 2000 g/t DDA and 1500 g/t sodium carbonate,a pyrolusite concentrate containing almost 40％ MnO with 71.5％ recovery is achieved by carrying out the ore flotation experiments on the tabling pre-concentrate.%在软锰矿阳离子浮选中添加十二胺,采用浮选实验、红外光谱分析、接触角测量和zeta电位测试等手段研究碳酸钠和氯化钙对方解石矿物的抑制作用.微浮选实验结果表明,这两种抑制剂都能明显地抑制方解石的浮选.而且,碳酸钠作为活化剂,能增加软锰矿的浮选性能.浮选实验和接触角测试结果表明,碳酸钠对方解石的选择性抑制作用要比氯化钙强.Zeta电位和红外光谱分析表明,碳酸钠减少了方解石矿物表面所带的负电荷,从而减少了十二胺在其表面的静电吸附.在pH=7.5,添加2000 g/t十二胺和1500g/t碳酸钠的浮选条件下,可得到含40％ MnO的软锰矿精矿,回收率达71.5％.