Research On The Flotation Of Rubidium-containing Lepidolite And Feldspar Under The Condition Of Weak Acid

Nowadays with the continuous development of science and technology,rubidium has been widely used in photoelectric,aviation,medical and other fields due to its unique physical and chemical properties,becoming one of the important elements in the application of high technology.There was no independent mineral for rubidium and it usually exists in mica in the way of isomorphism,or in salt lake and brine,so,the beneficiation for rubidium-containing mica was one of the main methods to recover rubidium.In this paper,a Australian rubidium-containing lepidolite ore was taken as the research object,and the pure minerals flotation behavior of rubidium-containing lepidolite and feldspar was mainly studied,and the floatability difference of two kinds of pure ores under different collecting agents,pH value and regulator was investigated and verified by artificial mixed ore.The adsorption mechanism of the collecting agents with rubidium-containing lepidolite and feldspar was studied by means of FTIR,zeta potential and XPS.The results of the minal test indicated that the three kinds of cationic collecting agents had collecting capacity and high recovery for rubidium-containing lepidolite and feldspar,and the three kinds of anionic collecting agent had poor collecting capacity and low recovery for rubidium-containing lepidolite and feldspar,while it was selective under acid conditions.Under the condition of pH=6,oxalic acid with amount 300 g/t,combination collector formed by DDA and SDBS with the concentration ratio of 1:1 and the total concentration was 5×10-4 mol/L,it showed that the recovery rate of rubidium-containing lepidolite was 83%,and feldspar was 9%respectively;the difference of flotation recovery of feldspar and rubidium-containing lepidolite was significant.The verification test results of the artificial mixed ores showed that,under the condition of above reagent system,the concentrate with 0.76%Rb2O grade and Rb2O recovery of 79.8%was obtained when the mass ratio of rubidium-containing lepidolite to feldspar was 1:1;when the mass ratio of rubidium-containing lepidolite to feldspar was 1:3,the concentrate with 0.58%Rb2O grade and Rb2O recovery of 70.2%was obtained.A satisfactory flotation separation effect was obtained.Research on adsorption mechanism between collecting agents and minerals surface:Solution chemistry showed that,DDA was mainly in the form of cation in the solution,while SDBS was in the form of anion in the solution.The potentiodynamic test result showed that,The PZC of rubidium-containing lepidolite was similar to that of feldspar;the potential decreased with the increase of pH value;when DDA acted alone,the potential moved in a positive direction,while SDS was added,the potential on the minerals surface moved in a negative direction;and the potential shift range of rubidium-containing lepidolite was smaller than that of feldspar.The adsorption capacity test showed that,the adsorption capacity of the combination collector on the rubidium-containing lepidolite surface was greater than that of feldspar.The infrared spectrum analysis showed that,when the combination collector adsorbed on the surface of rubidium-containing lepidolite and feldspar minerals,the form of adsorption was physical,and hydrogen bond was formed on the surface of rubidium-containing lepidolite.XPS showed that,the combination collector had chemical adsorption on the surface of rubidium-containing lepidolite.