离子液体反浮选磷石膏脱硅工艺及机理研究

Desilication Process of Phosphogypsum by Ionic Liquid Reverse Flotation and Mechanism Study

鄂西高硅型磷石膏采用传统的阳离子捕收剂浮选脱硅效果不理想,不利于磷石膏大规模资源化利用。近年来离子液体因其优秀的性能在浮选中被引入作为反浮选药剂,其绿色、稳定的特性符合现代选矿药剂的环保要求,因此,选用2种离子液体为脱硅捕收剂开展浮选试验并通过SEM-EDS、Zeta电位测试、FTIR等测试技术进行了机理研究。浮选试验结果表明:在矿浆p H值为7、MIBC用量150g/t、离子液体MY用量150g/t的条件下,采用1次反浮选工艺流程,得到的浮选精矿产率为83.24%、CaSO_(4)·2H_(2)O品位为93.35%、回收率96.34%,SiO_(2)含量降低至1.94%,实现了磷石膏中硅杂质的高效脱除。Zeta电位测试结果表明:离子液体MY与石英作用后表面电位正移最大可达51.49m V,而与石膏作用后表面电位仅略微增加,导致离子液体MY在石膏与石英之间发生选择性吸附。红外光谱分析结果显示:石英与离子液体MY、MZ作用后都产生了新的特征峰,说明2种离子液体均在石英表面发生了化学吸附。研究结果为高硅磷石膏资源化利用提供了可行的方案。

The effect of flotation desilication of high silicon phosphogypsum in western Hubei by traditional cationic collector is not ideal,which is not conducive to the large-scale resource utilization of phosphogypsum.In recent years,ionic liquids have been introduced as reverse flotation reagents in flotation due to their excellent performance.Their green and stable characteristics meet the environmental protection requirements of modern mineral processing reagents.Therefore,two ionic liquids are selected as desilication collectors to carry out flotation tests.The mechanism is studied by SEM-EDS,Zeta potential test,FTIR and other test techniques.The results of flotation test show that under the conditions of pulp pH value of 7,MIBC dosage of 150 g/t and ionic liquid MY dosage of 150 g/t,the flotation concentrate with yield of 83.24%,CaSO_(4)·2H_(2)O grade of 93.35%,recovery of 96.34%is obtained by one-time reverse flotation process.The content of SiO_(2) decreases to 1.94%,which realizes the efficient removal of silicon impurities in phosphogypsum.The results of Zeta potential test shows that the surface potential of ionic liquid MY shifts positively up to 51.49 mV after interacting with quartz,while the surface potential only increases slightly after interacting with gypsum,resulting in the selective adsorption of ionic liquid MY between gypsum and quartz.The results of infrared spectroscopy shows that new characteristic peaks are produced after the interaction of quartz with ionic liquids MY and MZ,indicating that the two ionic liquids are chemically adsorbed on the surface of quartz.The research results provide a feasible scheme for the resource utilization of high silicon phosphogypsum.