Research On Basic Theory And Technology Of Spodumene Flotation

Spodumene is the main silicate minerals of extracting lithium resources for now. Such ore is mainly distributed in granitic pegmatite and the gangue mineral is albite and quartz. In the process of beneficiation, the “three alkaline substances and two soaps” is used for the flotation separation. In the flotation of spodumene, the dosage of alkalines and soaps, location of added the agents and concentration of Ca2+, OH-, CO32- in the pulp are all the key factor of flotation. In addition, because of weathering pollution on the surface of spodumene and sludge contamination in the pulp, the flotability of the minerals are deterioration. The dissolved salt ions(such as Ca2+, Mg2+ and Fe3+) not only activated the spodumene but also the gangue mineral to reduce the separation results of the spodumene flotation. To solve these problems, the basic theory of flotation and utilization of such mineral resources were studied in this paper.The study includes consideration of anionic collector for flotation behavior of spodumene, feldspar and quartz to revealing three mineral flotation regularity. The research investigated the activation of Fe3+、Ca2+、Mg2+ and inhibition of Na2CO3 to spodumene, feldspar and quartz minerals. This study includes pure minerals flotation tests, flotation separation of artificial mixed minerals and actual ore flotation tests. On this basis, various measurements techniques and theoretical analysis have been carried out to study the mechanism of collector, metal ion activators, Na2CO3 inhibitor between the three minerals in this system.The results of pure minerals flotation tests indicate that the flotability of spodumene, albite and quartz is weak using Na OL collector. Fe3+, Ca2+, Mg2+ ions show a high activating reaction on the flotation of spodumene, albite and quartz. Na2CO3 have a certain inhibition of the three minerals. Fe3+ ions work best under neutral p H and sufficient activation on the spodumene and quartz at a low concentration, while the activation performance of albite is poor. The most efficient environment of Ca2+ ions is at very high p H values and Ca2+ ions cannot activate the three minerals sufficiently until the concentration of it is high enough. Mg2+ ions work best at p H=10, and activation of Mg2+ for spodumene, albite and quartz is not selective. Na2CO3 has better selective inhibition for spodumene, albite and quartz activated by Fe3+, Ca2+ ions, while the select inhibitory is bad by Mg2+ activation.The flotation tests of artificial mined minerals have been carried out with Fe3+, Ca2+, Mg2+ ions activation, Na2CO3 inhibitor and Na OL collector, the results indicate that these modifiers can separate spodumene, albite and quartz efficiently. And Fe3+ ions does best. The froth products containing Li2 O 6.42% were achieved, after the mixed minerals have been processed using Fe3+ ions in which spodumene : albite : quartz equals 1 :1 : 1, when spodumene : albite : quartz is 1: 2 : 2, we can get the products containing Li2 O 5.31% in the forth products. In the flotation tests of actual ore, cecause the minerals was severely weathering and contains a certain Fe3+, Ca2+, Mg2+ ions in the water. The collector is complex collector as flotation reagents, and not add any metal ion activation in the process of flotation.The results of mechanism study show that zeta-potential of spodumene, albite and quartz are positive after active by Fe3+, Ca2+, Mg2+ions. Na2CO3 could change the surface electrical of three minerals and there is a good selective inhibition between of spodumene, albite and quartz. The FT-IR analysis show that there is new substances generated on the surface of spodumene and quartz after the minerals contents with Na OL and the chemical adsorption was occurred between minerals surface and collector. The XPS analysis also show that the binding energy of Li on the surface of spodumene occurred a large shift and the minerals surface contain a certain amount of Ca2+, Mg2+ ions. After active by Ca2+、Mg2+ ions, the element of Li, Ca and Mg occurred a large displacement of the spodumene, this also indicated that the chemical adsorption occurred between spodumene and Na OL.The pilot tests show that compounding concentrates containing Li2 O 5.93% can be obtained from the run of mine containing Li2 O 1.30%. Using the traditional process of flotation separation of albite and quartz under acidic conditions, the albite concentration containing Na2O% and K2 O 11.59% and the quartz concentration containing Si O2 98.94%. The three minerals were separated effectively and achieve a utilization.