Study On Extraction Of Patassium From Natural Mineral Illite

Illite is a rich-potassium layered clay mineral,it is called the four main clay minerals in clay sedimentary rocks with kaolinite,chlorite,and montmorillonite.Illite is a hydrophilic silicate mineral.Because of its unique physical and chemical properties,it has been widely used in the fields of ceramic industry,paper industry,rubber and plastic fillers,chemical fertilizer industry,construction industry,environmental protection industry,fine chemical industry and so on.With the development of science and technology,the application scope of illite is also expanding.Jilin Yanbian Korean Autonomous Prefecture is rich in illite resources,but because of its complex origin and deep color,it is less likely to be put into use directly.Therefore,a series of potassium extraction schemes are designed based on the properties of potassium rich and high aluminum of the illite,and the release process of potassium ion in illite is studied in the dynamics.In this study,the high temperature moLten salt ion-exchange(the second chapter),hydrothermal acid leaching(the third chapter)and microwave assisted acid leaching(the fourth chapter)were used to study the potassium extraction process from illite.The X ray diffraction(XRD)and X ray fluorescence diffraction(XRF)were used to characterize the composition,structure and morphology of the materials before and after the reaction.The dissolution process of potassium from illite was revealed from the kinetic point of view by analyzing the changes of the components before and after the reaction.Through the experimental study,the following conclusions are obtained.(1)The process of potassium release from illite from illite in Yanbian Korean Autonomous Prefecture of Jilin province was investigated via high temperature moLten salt.The effects of the types and dosage of flux,calcination temperature and time,washing temperature and time,and solid-liquid ratio on the rate of potassium release were studied.The composition,structure and morphology of illite were characterized by electron scanning electron microscopy(SEM),X ray diffraction(XRD)and X ray fluorescence diffraction(XRF)respectively.The results show that calcium chloride additive has a great effect on the potassium release rate from illite and the potassium release rate is 95.84%under the optimum experimental conditions.Based on the dynamics analysis,the rate of potassium release process is controlled by an internal diffusion mode.The rate of potassium leaching of calcined slag is controlled by the surface chemical reaction.(2)To avoid high energy consumption caused by high temperature reaction,using hydrochloric acid as etching agent,the rules of leaching Al+ and K+elements from illite was studied via hydrothermal acid leaching process.On the basis of the orthogonal experiment,the factors of the hydrochloric acid concentration,leaching time,leaching temperature and the ratio of solid to liquid was investigated.X ray diffraction(XRD)and X ray fluorescence diffraction(XRF)were used to characterize the composition,structure and morphology of product.The results showed that the simultaneous dissolution of aluminum and potassium was achieved in the experiment.The dissolution rate of aluminum under the best experimental conditions was 96.07%and 93.89%respectively.The leaching kinetic study shows that the acid leaching process of alumina and potassium form illite can be described with the shrinking core model.The kinetic analysis reveals that the leaching process is controlled by fluid film control at low temperature and the leaching process is controlled by chemical reaction at high temperature.(3)In order to reduce the reaction time and increase the process efficiency,microwave irradiation method was used to replace the traditional heating method,and the acid leaching products were carefully characterized.The effects of concentration of hydrochloric acid,leaching time,leaching temperature and solid-liquid ratio on the dissolution rate of potassium from illite were investigated via orthogonal experiment.Electron scanning electron microscopy(SEM),X ray diffraction(XRD),X ray fluorescence diffraction(XRF)and N2 desorption adsorption apparatus(BET)were used to characterize the composition,structure,morphology,specific surface area and pore size distribution of product.The results show that microwave acid leaching 30min,K+dissolution rate is 92.44%,The acid leaching residue was high purity silica(>95%),whose the largest surface area of 114 m2/g and mean diameter of 32 nm,respectively.The leaching kinetics of potassium from illite can be described successfully by the shrinking core model,and the leaching process is mainly controlled by chemical reaction.