Effect of solution conditions on depression of chlorite using CMC as depressant  

作　　者：冯博 冯其明 卢毅屏 李浩 

机构地区：[1]School of Mineral Processing and Bioengineering, Central South University

出　　处：《Journal of Central South University》2013年第4期1034-1038,共5页中南大学学报（英文版）

基　　金：Project(51174229) supported by the National Natural Science Foundation of China

摘　　要：The effect of solution conditions on the depression of chlorite using CMC (carboxymethyl cellulose) as depressant was studied through flotation tests and adsorption measurements. Flotation and adsorption tests were first studied as a function of initial solution conditions. The results show that electrostatic repulsion between CMC molecules and chlorite surface hinders the approach of the CMC molecules to the chlorite surface and CMC adsorbs to a great extent at high ionic concentration (10-4 mol/L ions as opposed to 0 mol/L ions) or low pH (3 as opposed to 9). The enhanced adsorption density is attributed to the decreased electrostatic repulsion between CMC and mineral surface. The solution condition that yielded the lowest initial adsorbed amount (0 mol/L ions, pH 9) was used as a reference to investigate the response of the adsorbed CMC layer to a switch in solution conditions after adsorption. The two kinds of solution switches (reducing the solution pH or increasing ionic concentration) result in an increased depression effect of CMC on chlorite flotation, as a result of conformational change of CMC pre-adsorbed layer. The change in the flotation recovery of the CMC-coated chlorite following the solution switches is reversible.The effect of solution conditions on the depression of chlorite using CMC （carboxymethyl cellulose） as depressant was studied through flotation tests and adsorption measurements. Flotation and adsorption tests were first studied as a function of initial solution conditions. The results show that electrostatic repulsion between CMC molecules and chlorite surface hinders the approach of the CMC molecules to the chlorite surface and CMC adsorbs to a great extent at high ionic concentration （10^-4 mol/L ions as opposed to 0 mol/L ions） or low pH （3 as opposed to 9）. The enhanced adsorption density is attributed to the decreased electrostatic repulsion between CMC and mineral surface. The solution condition that yielded the lowest initial adsorbed amount （0 mol/L ions, pH 9） was used as a reference to investigate the response of the adsorbed CMC layer to a switch in solution conditions after adsorption. The two kinds of solution switches （reducing the solution pH or increasing ionic concentration） result in an increased depression effect of CMC on chlorite flotation, as a result of conformational change of CMC pre-adsorbed layer. The change in the flotation recovery of the CMC-coated chlorite following the solution switches is reversible.

关 键 词：CHLORITE carboxymethyl cellulose ION PH conformational change 

分 类 号：TD97[矿业工程—选矿] TD923.1