Study On Effect Of Addition Order Of Regulators And Collectors On Flotation Separation Of Typical Sulfide Minerals

The addition order of reagents on flotation is usually that the regulators are added before the collectors,but in the research and production practice,it is found that sometimes the flotation performance indexes by adding collectors before regulators are better.It is not clear whether this is an individual case or a general rule.At present,it is lack of systematic research on the effect of the addition order of regulators and collectors on the floatability of minerals.Therefore,the influences of the addition order of the collectors(diethyldithiocarbamate,Z-200 and potassium butylxanthate)and the regulators(zinc sulfate,copper sulfate,sodium sulfite,sodium sulfide,dextrin,sodium humate,cationic guar gum and DP115(a kind of modified polyacrylamide organic macromolecule))on the floatability of the sulfide minerals(i.e.chalcopyrite,galena,sphalerite and pyrite)were systematically studied.The results of single mineral flotation test showed that the addition order of regulators and collectors have different influences on the flotation of sulfide minerals.Compared with regulators added before collectors in the flotation of sulfide minerals,regulators added after collectors have little effect on the flotation of the minerals,or can enhance or weaken the floatability of the minerals.This can enhance the separation selectivity for sulfide minerals of the flotation process.In the flotation system of galena and sphalerite using diethyldithiocarbamate as collector and zinc sulfate or cationic guar gum as regulator and in the flotation system of chalcopyrite and sphalerite(or galena)using Z-200 and DP115 as collector and regulator respectively,it was more favourable for the flotation separation to add the regulator zinc sulfate,cationic guar gum or DP115 after the collector diethyldithiocarbamate or Z-200.The results of flotation tests on artificial mixed sample of minerals showed that for galena-sphalerite(1:1)artificial mixed sample using diethyl-dithiocarbamate and zinc sulfate or cationic guar gum as collector and regulator respectively,under the same flotation conditions,the selective separation index was 6.18 or 3.07 higher when the zinc sulfate or cationic guar gum was added after diethyldithiocarbamate,compared with that when the zinc sulfate or cationic guar gum was added before diethyldithiocarbamate.The results of the flotation separation of actual ores were in good agreement with those of single mineral flotation test and artificial mixed sample flotation separation,which verified the results of flotation separation of single mineral and artificial mixed sample.For chalcopyrite-sphalerite(1:1)artificial mixed sample using Z-200 and DPI 15 as collector and regulator,respectively,the selective separation index was 10.09 higher when the DP115 was added after Z-200,compared with that when the DP115 was added before Z-200.For chalcopyrite-galena(1:1)artificial mixed sample using Z-200 and DP115 as collector and regulator,respectively,the selective separation index was 4.88 higher when the DP115 was added after Z-200,compared with that when the DP115 was added before Z-200.The mechanisms of adding the inorganic(zinc sulfate)and organic(cationic guar gum or DP115)regulator after the collector(diethyldithiocarbamate or Z-200)was favourable for the flotation separation were revealed by applying adsorption determination and spectroscopic measurements such as FTIR,XPS and TOF-SIMS.The mechanism of adding the regulator zinc sulfate after the collector diethyldithiocarbamate was favourable for the flotation separation of galena and sphalerite was as follows:the adsorption capacity of zinc sulfate on the surface of sphalerite was enhanced,while the zinc sulfate had little effect on the adsorption of the collector diethyldithiocarbamate on the surface of galena,it resulted in the further increase of difference in floatability between galena and sphalerite;The mechanism of adding the regulator cationic guar gum or DP115 after the collector diethyldithiocarbamate or Z-200 was favorable for the flotation separation of galena and sphalerite or chalcopyrite and sphalerite(or galena)was as follows:it resulted in the further increase of difference in floatability between galena and sphalerite,or between chalcopyrite and sphalerite(or galena)from the decrease of the inhibitory effect of the regulator cationic guar gum or DP115 on the adsorption of the collector diethyldithiocarbamate or Z-200 on the surface of the target mineral(galena or chalcopyrite).In this study,a variety of modern analysis and testing methods were used to elucidate the effect law of the addition order of the regulators and collectors on the flotation separation of typical sulfide minerals,and the effect mechanism of the dosing order on the adsorption and desorption of the collectors on the mineral surfaces was revealed.The results of this doctoral dissertation provide an important reference for the process optimization of selective flotation separation of typical copper,lead and zinc sulfide ores.