Study On The Micro-calorimetric Kinetics Of The Adsorption Of Collector On Mineral Surface In The Separation Of Galena And Sphalerite

The galena and sphalerite resources in China have the characteristics of low grade,complex symbiotic relationship and good natural floatability,how to effectively separate galena and sphalerite and improve resource utilization efficiency has been the focus of research.The separation of galena and sphalerite mainly used flotation method,but the conventional test method can not fully and concretely reflect the detailed information of the interaction between the reagent and the mineral.The micro-thermokinetics method is a new attempt,it can continuously and concretely present the details of the whole reaction,heat effect value,the curve of calorimetric data and the thermokinetics law,it also provides a theoretical basis for separation of galena and sphalerite.This paper carried out the calorimetric and flotation tests about the adsorption of butyl xanthate,ammonium dibuyl dithiophosphate and diethyl dithiocarbamate with galena and sphalerite surface at different temperature and pH value of pulp solution conditions,it also carried out the measure of the adsorption amount by UV spectrophotometer to check the results.The test results show that the adsorption process of collector with galena and sphalerite and are exothermic reactions.With the increase of temperature,the liberated heat gradually decreases and the reaction rate constant increases.In different pulp solution conditions,the apparent activation energy required for the adsorption of collectors on galena surface is lower than the apparent activation energy required for the adsorption on the surface of sphalerite,the higher the activation energy is,the more difficult of the adsorption on mineral surface to occur and the recovery of flotation test also be lower.Similarly,the flotation tests show that the collector ability of three collectors on galena is stronger than that of sphalerite.The difference of apparent activation energy Ea(?Ea_{| galena-sphalerite |})of the adsorption of butyl xanthate on the galena and sphalerite surface is :?Ea_pH=12>?Ea_pH=10>?Ea_pH=7.In the flotation test,under the pulp solution of pH is 12,the difference between the recovery rate of butyl xanthate with galena and sphalerite reached the maximum value at 76.49%,so when the pH is 12,the selectivity of butyl xanthate is the best.The ?Ea_{| galena-sphalerite |}of the adsorption of ammonium dibuyl dithiophosphate on the galena and sphalerite surface is: ?Ea_pH=10>?Ea_pH=12>?Ea_pH=7,The ?Ea_{| galena-sphalerite |}of the adsorption of diethyl dithiocarbamate on the galena and sphalerite surface is : ?Ea_pH=12>?Ea_{p H=10}>?Ea_pH=7,the flotation test results also show that when the pH is 10,the difference between the recovery rate of galena and sphalerite is the largest,reaching to 66.40%,the difference of recovery rate between galena and sphalerite is the maximum value of 80.49%.It show that under this condition,the ammonium dibuyl dithiophosphate and diethyl dithiocarbamate all have the best selectivity.The apparent activation energy difference and recovery rate difference of the three collectors were compared under the optimum conditions,they all explained that the selectivity of diethyl dithiocarbamate is higher than that of butyl xanthate and ammonium dibuyl dithiophosphate.The flotation test results are consistent with the calorimetric results,so the results are reliable.In the determination of adsorption,the adsorption capacity of three kinds of collector on galena surface is higher than sphalerite surface.When the pH value was 12,the difference between the adsorption capacity of butyl xanthate on the galena surface and sphalerite surface was maximum.When the pH value was 10,the difference of the adsorption capacity of ammonium dibuyl dithiophosphate was maximum and the pH value was 12,the difference of the adsorption capacity of diethyl dithiocarbamate was maximum.The results are in accordance with the flotation test results.