基于锂辉石与绿柱石和长石等铝硅酸盐矿物的表面皆含有活性Al原子,表面晶体化学特性是产生选择性浮选分离的决定性因素,通过不同粒级单矿物浮选实验、Zeta电位测试、红外光谱分析、密度泛函理论计算及分子动力学模拟等方法系统研究油酸钠浮选锂辉石的表面晶体化学及各向异性。结果表明:锂辉石浮选回收率随pH增大先增加而后减小,当pH=8.5左右,浮选回收率达到最大值;在一定粒度范围内,粒度越粗,锂辉石浮选回收率越高;锂辉石表面Al质点与油酸钠发生化学吸附作用;锂辉石晶面单位面积的断裂键数以及与油酸钠的相互作用能由大到小依次为(110)、(001),其是导致不同粒级锂辉石浮选行为差异性的根本原因。
Due to the same active Al atoms contained by spodumene, beryl and feldspar, the characteristic surface crystal chemistry of minerals was found to be the major contributing factor for the selectivity flotation separation. The surface crystal chemistry and anisotropy of spodumene flotation with sodium oleate were studied using single mineral flotation tests, zeta potential measurements, infrared spectral analysis, density functional theory calculation and molecular dynamics simulation. The results show that the flotation recovery rate first increases, but then decreases with the increasing pH. When the pH=8.5, the flotation recovery rate reaches maximum value. In the appropriate particle size range, particle size is much more coarse, the flotation recovery is higher, which shows Al sites on the surface of minerals react with NaOL by chemisorption. The order of the surface broken bond densities of the spodumene crystal planes and interaction energy with NaOL is (110), (001), which is a leading cause of the difference flotation behavior of spodumene in different particle size fractions.