(1. 中南大学 冶金与环境学院,长沙 410083;
2. 中南大学 资源加工与生物工程学院,长沙 410083)
摘 要: 通过纯矿物浮选试验研究了油酸钠体系下聚天冬氨酸(PASP)、聚马来酸(HPMA)和聚环氧琥珀酸(PESA)对白钨矿和萤石的选择性抑制作用。结果表明:PASP的选择性抑制作用最强,HPMA的次之,PESA的最差。当pH>9.5时,采用PASP作抑制剂有望实现白钨矿和萤石的浮选分离。实际矿石浮选试验表明,对于WO3含量为0.16%、CaF2含量为11.28%的浮选给矿,在粗选作业中加入40 g/t PASP作抑制剂,经一粗一扫的闭路实验流程,得到的钨粗精矿中WO3品位由0.70%提高到1.43%,回收率为87.49%,CaF2回收率从41.17%降至23.27%。动电位测试、红外光谱分析和X射线光电子能谱分析结果显示,PASP可通过其分子结构中的羧基与白钨矿和萤石表面的Ca2+作用而发生化学吸附,同时在萤石表面亦有静电吸附。此外,PASP的吸附阻碍了油酸钠在萤石表面的吸附,而对其在白钨矿表面的吸附影响较小,导致其疏水性和可浮性的差异,从而实现浮选分离。
关键字: 白钨矿;萤石;浮选分离;聚羧酸;选择性抑制
(1. School of Metallurgy and Environment, Central South University, Changsha 410083, China;
2. School of Mineral Processing and Bioengineering, Central South University, Changsha 410083, China)
Abstract:The selective inhibition effects of polyaspartic acid (PASP), polyepoxysuccinic acid (HPMA) and polymaleic acid (PESA) on scheelite and fluorite with sodium oleate (NaOL) were investigated through pure minerals flotation tests. The results show that PASP exhibits the strongest selective depression, followed by HPMA and PESA. The flotation separation of scheelite from fluorite can be achieved in the addition of PASP when pH is higher than 9.5. The real ore flotation tests show that for the feeding containing 0.16% WO3 and 11.28% CaF2, when PASP is used as depressant, the WO3 grade of the obtained rough scheelite concentrate can increase from 0.70% to 1.43% with a recovery of 87.49% through a closed-circuit process of one roughing and one scavenging. And the CaF2 recovery decreases from 41.17% to 23.27%. The zeta potential measurement, infrared spectroscopic analysis and X-ray photoelectron spectroscopy analysis results indicate that the chemical adsorption of PASP occurs on scheelite and fluorite surface through the interaction between carboxyl and Ca2+, and the electrostatic adsorption of PASP also occurs on fluorite surface. In addition, the adsorption of NaOL on fluorite surface is decreased by the adsorption of PASP, but the adsorption of NaOL on scheelite surface is little affected, resulting in the difference in hydrophobicity and floatability.
Key words: scheelite; fluorite; flotation separation; polycarboxylic acid; selective depression