Microcalorimetry Dynamics Research On The Flotation Separation Of Chalcopyrite And Sphalerite

It is an attempt and innovation with important significance to combine microcalorimetry with conventional flotation tests and introduce microcalorimetry into the study of beneficiation theory for exploring the adsorption effect of flotation reagents on mineral surfaces as well as the mechanism of mineral dissolution.Through microcalorimetry,the thermodynamic rules of the inhibitory processes of three kinds of inhibitors under the diethyldithiocarbamate system(zinc sulfate,sodium hexametaphosphate and sodium humate)on chalcopyrite and sphalerite were systematically studied.The action mechanisms of the three inhibitors were explained from the thermodynamic perspective and verified through the single mineral flotation test and adsorption amount determination.The single mineral flotation test showed that the optimum dosage of ethyl nitrogen was 4×10-4 mol·L-1,the optimum dosage of copper sulfate was 2×10-4 mol·L-1,and the optimum dosage of the inhibitor was 2×10-4 mol·L-1.With the increase of pH value of pulp,the inhibition effect on sphalerite was greater than that on chalcopyrite.The inhibition effects of the three inhibitors was: sodium hexametaphosphate > zinc sulfate > sodium humate.The thermokinetic reaction of the adsorption of ethyl nitrogen by chalcopyrite and sphalerite surface activated by copper sulfate was an exothermic process;with the increase of the reaction temperature,the reaction time and the curve peak area of thermokinetics decreased,indicating that with the increase of temperature,the reaction rate K increased and the reaction heat Q decrease.The apparent activation energy indicates the energy required for the adsorption of reagents on the mineral surface.The higher the apparent activation energy is,the more difficult it is for the reagent to be adsorbed on the mineral surface.Under the same adsorption condition,the apparent activation energy of adsorption of ethyl nitrogen on the surfaces of chalcopyrite and activated sphalerite increased with the increase of pH.The apparent activation energy Ea and ?Ea |chalcopyrite-sphalerite| showed that sodium hexametaphosphate could more easily inhibit the activation of sphalerite to increase the apparent activation energy of activated sphalerite and play the inhibitory role The inhibitory effect of sodium humate on activated sphalerite was poor.The apparent activation energy and the activation enthalpy of sphalerite changed little after activation.The three kinds of inhibitors had little effect on the apparent activation energy and activation enthalpy of chalcopyrite.The inhibitory effects of the three inhibitors on chalcopyrite was: sodium humate > zinc sulfate > and sodium hexametaphosphate;the inhibitory effects on sphalerite was: sodium hexametaphosphate > zinc sulfate > sodium humate.The microcalorimetry results were consistent with that of the single mineral flotation test.The adsorption capacity of ethyl nitrogen on the surfaces of chalcopyrite and sphalerite under different conditions were verified by UV spectrophotometer.