(中南大學(xué) 礦物工程系， 長沙 410083)
摘 要: 研究了硬質(zhì)和軟質(zhì)高嶺土中的高嶺石晶體結(jié)構(gòu)、晶體形態(tài)與表面性質(zhì)之間的關(guān)系及其對浮選行為的影響。硬質(zhì)和軟質(zhì)高嶺土表面Zeta電位隨pH值的變化規(guī)律基本相同，具有相近的表面零電點(diǎn)(PZC)值。幾種硬質(zhì)高嶺土的PZC值的變化范圍為2.5～3.8。在較寬的pH值范圍，軟質(zhì)高嶺土比硬質(zhì)高嶺土的電位高。鋁土礦中高嶺石以硬質(zhì)高嶺石為主，結(jié)晶有序度低，與藥劑作用不強(qiáng)，可浮性較軟質(zhì)高嶺石差，在鋁土礦反浮選中，需強(qiáng)化對高嶺石的捕收作用。
關(guān)鍵字: 浮選； 高嶺土； 高嶺石； 表面性質(zhì)； 晶體結(jié)構(gòu)
kaolinite in hard kaolins and soft kaolins
JIANG Hao， CAO Xue-feng， Qiu Guan-zhou
（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
