(中南大学 矿物工程系, 长沙 410083)
摘 要: 分析了我国铝土矿中一水硬铝石和铝硅酸盐脉石矿物的晶体结构与表面性质。一水硬铝石与铝硅酸盐脉石矿物晶体结构的差异、表面断裂的Al-O和Si-O键及表面离子活性区的差别,可影响矿物表面的润湿性与可浮性,类质同象及各种晶格杂质离子也将影响浮选剂与矿物表面的相互作用和矿物可磨性。提出了正浮选、反浮选铝硅分离的技术原型,用溶液化学计算研究了其基本原理。结果表明:通过溶液化学计算可确定阴离子捕收剂正浮选脱硅时捕收剂,分散剂和pH三者之间的匹配关系;矿物的PZC与捕收剂的pKa值是阳离子捕收剂反浮选的主要控制参数;阴离子捕收剂反浮选时,铅盐和钙盐是浮选铝硅酸盐较理想的活化剂。
关键字: 正浮选; 反浮选; 溶液化学; 铝土矿
of diasporic bauxite
(Department of Mineral Engineering, Central South University,
Changsha 410083, P.R.China)
Abstract:The crystal structure, wettability and floatability of diaspore and other gangues like kaolite, illite and pyrophyllite were discussed. Differences of wettability and floatability between diaspore and aluminium silicate minerals are due to the differences of crystal structure between diaspore and aluminium silicate minerals, and of the part Al-O, Si-O bonds, and the metal ions on the surface of the minerals. The technological schemes of direct-or reverse-flotation separation of aluminum-silicate minerals from bauxite were suggested. The fundamentals involved the technologies were studied. The relationship of collectors, dispersant and pH can be determined by solution chemical calculation in the direct flotation of bauxite by anionic collectors. The PZC of minerals and the pKa of collectors are the dominating control parameter in the reverse flotation by cationic collectors. The lead salt and calcium salt are effective activators in the metal ions activation flotation by the anionic collectors.
Key words: direct flotation; reverse flotation; solution chemistry; bauxite