油胺浮选体系PO_4^(3-)对石英的抑制作用

Investigation of the Depressing Effect of PO_4^(3-) on Quartz in Oleylamine Flotation System

为了更加深入地认识胶磷矿胺类捕收剂反浮选脱硅过程中难免离子PO_4^(3-)的影响,考查了PO_4^(3-)存在条件下石英纯矿物浮选行为,并结合Zeta电位分析及PO_4^(3-)的Φ-p H图,分析了PO_4^(3-)的抑制作用机理。研究结果表明,PO_4^(3-)对油胺浮选石英具有明显的抑制作用,并且p H为4~5时的抑制作用明显大于pH为8~10;PO_4^(3-)在p H=4~5时以H_2PO_4^-为主,pH=8~10时以HPO2-4为主,抑制作用是由于PO_4^(3-)在溶液中水解生成的H_2PO_4^-及HPO_4^(2-)吸附于石英表面荷正电区域,使石英表面亲水。

In order to further understand the influence of PO4^3- ions on the removal of silicon from collophane by reverse flotation of amine collectors,the flotation behavior of pure quartz in the presence of PO4^3- is examined. Combined with zeta potential analysis and Φ-p H diagram of PO4^3- ions,the inhibition mechanism of PO4^3- is analyzed. The results show that PO4^3- ions have a significant inhibitory effect on the flotation of quartz by oleamine,and the inhibitory effect at p H = 4 ~ 5 is significantly greater than that at p H = 8 ~ 10; H2PO4^- ions are the primary species at pH = 4 ~ 5 and HPO4 ^2- at pH = 8 ~ 10. The inhibition effect could be attributed to the adsorption of H2PO4^- and HPO4^2- ions hydrolyzed from PO4^3- ions on the positive region of the quartz surface,which makes the quartz surface hydrophilic.