SCMG对煤和蒙脱石浮选分离的影响

摘要

以田菁胶、氢氧化钠、一氯乙酸为原料,通过醚化反应合成一种浮选抑制剂羟甲基田菁胶(SCMG),通过矿物浮选实验、药剂吸附实验及X线光电子能谱(XPS)分析,考察SCMG对煤和蒙脱石浮选分离的影响及抑制机理.研究结果表明:SCMG具有良好的选择抑制性,可显著抑制蒙脱石上浮;当其质量分数为500 g/t时与无抑制剂时相比,精煤灰分(质量分数)可降低17.25％;蒙脱石和煤表面对SCMG吸附量的差异是导致SCMG抑制具有选择性的主要因素.蒙脱石和煤对SCMG的吸附过程都趋近于单层吸附,且蒙脱石的Langmuir吸附常数KA大于煤的吸附常数,在矿浆中SCMG会优先吸附在蒙脱石表面;SCMG在煤和蒙脱石表面的吸附可能为化学吸附,在2种矿物表面的吸附厚度分别约为0.26 nm和0.68 nm.%A type of inhibitor ethyloic sesbania cannabian pers gum (SCMG) was obtained by etherification of sesbania gum with sodium hydroxide and chloroacetic acid. The effect of SCMG on separation of coal and montmorillonite and the inhibition mechanism of SCMG were investigated by mineral flotation, adsorption experiment and X-ray photoelectron spectroscopy (XPS) analysis. The results show that SCMG has good selectivity for inhibition, which depresses the flotation of montmorillonite observably. With SCMG mass fraction of 500 g/t, the ash content (mass fraction) of flotation concentrate decreases by 17.25％ compared with the one without inhibitor. The different adsorption capacities of coal and montmorillonite to SCMG make SCMG own selective inhibition. The SCMG adsorption process of coal and montmorillonite ends to be monolayer adsorption. Langmuir adsorption constantKA of montmorillonite is larger than that of coal, which makes montmorillonite absorb SCMG preferentially. SCMG is absorbed on the surface of coal and montmorillonite by chemical adsorption, with the thickness of adsorption layer being about 0.26 nm and 0.68 nm, respectively.