( 中南大學(xué) 資源加工與生物工程學(xué)院， 長沙 410083)
摘 要: 采用季銨鹽DTAL作捕收劑，研究了氯化鈉對(duì)一水硬鋁石和葉蠟石浮選的影響及其作用機(jī)理。隨著氯化鈉濃度的增加，葉蠟石的浮選回收率顯著提高，而一水硬鋁石的可浮性受其影響很小。機(jī)理研究表明：氯化鈉對(duì)一水硬鋁石的zeta-電位沒有影響，而能顯著降低葉蠟石的zeta-電位，增強(qiáng)捕收劑與葉臘石的靜電作用，促進(jìn)捕收劑的吸附而活化其浮選；葉蠟石表面電位的降低是因?yàn)槁入x子對(duì)葉蠟石存在選擇性吸附作用并對(duì)其結(jié)構(gòu)進(jìn)行插層，使得葉蠟石的層間距從0.93 nm增大至1.40 nm。溶液化學(xué)計(jì)算表明：氯化鈉改變?nèi)芤旱碾x子強(qiáng)度，顯著降低了季銨鹽陽離子表面活性劑的臨界膠束濃度，使得吸附了捕收劑的礦物表面更容易疏水上浮。
關(guān)鍵字: 氯化鈉； 插層作用； 特性吸附； 臨界膠束濃度； 浮選
（ School of Resource Processing and Bio-engineering,
Central South University, Changsha 410083, China）
Abstract: The effects and mechanisms of sodium chloride on the flotation of diaspore and pyrophyllite with the cationic quaternary ammonium DTAL as a collector were studied. The presence of sodium chloride was determined to activate the flotation of pyrophyllite, leaving diaspore flotation unaffected. Zeta potential measurements corresponded to the flotation tests. It is indicated that sodium chloride decreases marked by the zeta potential of pyrophyllite, leaving the zeta potential of diaspore unaffected. The decline of zeta potential can increase the electrostatic interaction between collectors and pyrophyllite, accordingly prompting the adsorption of the collector and activated the flotation of pyrophyllite. Chloride ion can be selectively adsorbed on the pyrophyllite and the intercalation in the layers of pyrophyllite which resulted in the swell of the d space from 0.93 nm to 1.40 nm. Solution chemistry demonstrates that electrolytical ion would decrease the critical micelle concentration and increase the hydrophobility of the collector, which have benefits on the separation of diaspore and pyrophyllite.
Key words: sodium chloride; special adsorption; intercalation; critical micelle concentration; flotation
