Study On Inhibition Performance And Mechanism Of Modified Sodium Silicate DWY-1 In Spodumene Flotation System

Although China has abundant reserves of lithium resources,there are problems such as low grade and fine granularity of intercalation.At present,the main process for the separation of spodumene ore is flotation.In nature,spodumene is often in close symbiosis with silicate minerals such as quartz and feldspar.Therefore,there are problems in separating spodumene from such silicate minerals in flotation separation,such as difficulty in sorting,a large dosage of medicament,poor selectivity and a low flotation recovery rate.As a commonly used inhibitor of flotation,water glass has a good inhibitory effect on silicate gangue minerals such as quartz.Therefore,water glass can be modified to improve its selectivity.In this paper,three single minerals of spodumene,quartz and albite were studied to study the inhibitory properties of different types of water glass and modified water glass in the spodumene flotation system.First,under the system of sodium oleate as the collector,the effect of five different modulus of water glass on the flotation of three single minerals of spodumene,quartz and albite were studied.The results showed that:water glass with modulus of 2.17,2.25 and 2.50 could effectively separate spodumene and quartz,water glass with the modulus of 2.25,2.50 and 3.30 could have a certain effect on the separation of spodumene and albite.It could be seen that water glass with a modulu of 2.50 could simultaneously inhibit quartz and albite to a certain extent.Therefore,the flotation separation effect of modified sodium silicate with modulus of 2.50,2.80 and 3.30 using trivalent iron was further investigated.It could be seen from the results that the modified salted water glass DWY-1 obtained under the conditions of a modulus of 2.50 and a mass ratio of water glass to ferric iron of 20:1 could simultaneously inhibit quartz and albite,and effectively recovered spodumene,at the same time,a good separation effect was achieved.When using DWY-1 as an inhibitor,the flotation test could be performed on the binary artificial mixed ore of spodumene-quartz,spodumene-albite and the ternary artificial mixed ore of spodumene-quartz-albite,the flotation separation of spodumene and gangue minerals could be realized.Finally,first-principles calculations,XPS testing,atomic force microscopy,Zeta potential measurement and infrared spectroscopy were used to systematically study the inhibitory mechanism of DWY-1 on the surface of spodumene,quartz and albite minerals.From the results of mineral crystals and surface calculations,it could be seen that the common dissociation surface was the surface of the oxygen end,so it would have strong electronegativity,but the surface of the spodumene had exposed lithium atoms,which would provide a part of the positive charge,so the surface electronegativity was weaker than that of albite and quartz.According to the results of solution chemistry calculations and related literature analysis,it could be concluded that the main component of DWY-1 was polymer Fe2-[O2Si(OH)2]22+.which was a cationic ilhibitor and was easier to adsorb on the anion surface.According to the results of Zeta potential detection,after the addition of activator trivalent iron,all three minerals showed a trend of frrst increasing and then decreasing potential.However,due to the surface properties of spodumene,the rate of decrease was slower than that of the other two minerals.This result was also in good agreement with the result of the surface calculation.Therefore,in a certain pH range,the spodumene surface could be positively charged while the other two minerals were negatively charged.At this time,the selective adsorption of DWY-1 could be achieved and albite and quartz could be inhibited.XPS and infrared detection results also proved that DWY-1 was selectively adsorbed on the surface of albite and quartz,preventing the adsorption of sodium oleate on the surface of albite and quartz,and achieving a good separation effect.Finally,it could be seen from the results of the atomic force microscope that the spodumene surface after adding the inhibitor DWY-1 still had a large amount of island-like spots formed by the adsorption of sodium oleate,while the collectors couldn’t be observed on the surface of albite and quartz.The adsorption of sodium oleate proved that the inhibitor DWY-1 has an inhibitory effect on these two minerals.