精炼塔尔油在磷酸盐浮选中的应用及QCM-D吸附研究

Phosphate flotation and QCM-D adsorption study of refined tall oil

对Georgia-Pacific公司新开发的精炼塔尔油捕收剂GP193G75在佛罗里达CF Industries公司的磷酸盐浮选中应用效果进行了研究.采用具有测定能量耗散功能的石英晶体微天平(QCM-D)研究了GP193G75在羟基磷灰石(HAP)表面的吸附过程,并与油酸钠和CF Industries公司目前所用的药剂粗塔尔油脂肪酸PR1进行了比较.考察了捕收剂用量、pH值、柴油用量和浮选时间等参数对GP193G75浮选效果的影响.结果表明,当pH值为10,捕收剂用量为0.45kg.t-1,且与柴油用量的比例为9∶8时,GP193G75的正浮选P2O5回收率最高可达到91.7%.QCM-D测定结果显示,GP193G75与油酸钠有相似的吸附过程,但GP193G75比油酸钠更易于且更快在羟基磷灰石表面吸附.在相同条件下,与PR1相比,GP193G75形成的吸附层密度更大,而且吸附更牢固,因此可以使羟基磷灰石表面的疏水性更强,从而得到较高的浮选效果.

GP193G75,a newly developed refined tall oil supplied by Georgia-Pacific Chemicals LLC,was investigated as a collector for the flotation of phosphate ore from CF Industries＇ phosphate rock mine in Florida.Its adsorption on the surface of hydroxyapatite was characterized using a quartz crystal microbalance with dissipation（QCM-D）in comparison with sodium oleate and the plant collector of CF Industries（PR1）which was the mixed crude tall oil fatty acid.The effect of the new collector GP193G75 on phosphate flotation was evaluated at different process parameters such as collector dosage,pH values,diesel dosage and flotation time.The results show that the highest recovery of 91.7% is achieved when the refined tall oil is used at the dosage of 0.45kg·t^-1 at pH 10 with a 9∶8 mass ratio of fatty acid to diesel.The data of QCM-D show the similar adsorption process with GP193G75 and sodium oleate,and GP193G75 adsorbs on hydroxyapatite more readily and quickly than sodium oleate.In comparison with PR1,GP193G75 forms a higher adsorption density and a more rigid adsorption layer,which produce a stronger hydrophobicity and a better flotation performance.