(中南大学 矿物工程系， 长沙 410083)
摘 要: 研究了硬质和软质高岭土中的高岭石晶体结构、晶体形态与表面性质之间的关系及其对浮选行为的影响。硬质和软质高岭土表面Zeta电位随pH值的变化规律基本相同，具有相近的表面零电点(PZC)值。几种硬质高岭土的PZC值的变化范围为2.5～3.8。在较宽的pH值范围，软质高岭土比硬质高岭土的电位高。铝土矿中高岭石以硬质高岭石为主，结晶有序度低，与药剂作用不强，可浮性较软质高岭石差，在铝土矿反浮选中，需强化对高岭石的捕收作用。
关键字: 浮选； 高岭土； 高岭石； 表面性质； 晶体结构
kaolinite in hard kaolins and soft kaolins
（Department of Mineral Engineering，
Central South University，Changsha 410083， P.R.China）
Abstract: The crystal structure， crystal photography and surface property of kaolinite in hard kaolins and soft kaolins have been studied. The surface zeta potential＇s variation of the hard kaolins as a function of pH is almost the same asthat of the soft kaolin. The surface points of zero charge (PZC) of the different kaolins are almost the same. The PZC of the hard kaolins varies from 2.5 to 3.8. In the broad range of pH， the zeta potential of soft kaolin is higher than that of hard kaolins. The crystallinity index of hard kaolin is lower than that of soft kaolin. The floatability of hard kaolin is lower than that of soft kaolin. Hard kaolin is the dominant kaolin in bauxite. It is required to explore new type collector for hard kaolin in order to separate selectively kaolin from diaspore in bauxite.
Key words: flotation; kaolin; kaolinite; surface property; crystal structure
