1 Introduction Songxian at East Qinling mountains in China possesses more than 100 million tons potassic syenite with the average K2O content of 13%and the main mineral phase of K-feldspar which is a kind of potential...1 Introduction Songxian at East Qinling mountains in China possesses more than 100 million tons potassic syenite with the average K2O content of 13%and the main mineral phase of K-feldspar which is a kind of potential potassium展开更多
Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldsp...Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca（OH）_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,（Na, K）_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.展开更多
基金the funds from China Geological Survey Project(12120113087700)Fundamental Research Funds for the Central Universities(2652014017)
文摘1 Introduction Songxian at East Qinling mountains in China possesses more than 100 million tons potassic syenite with the average K2O content of 13%and the main mineral phase of K-feldspar which is a kind of potential potassium
基金granted by China Geological Survey Project(12120113087700)Fundamental Research Funds for the Central Universities(2652014017)+10 种基金the National Eleventh Five-year Supporting Plan for Science and Technology(2006BAD10B04)Specialized Research Funds for Doctoral Program of Higher Education(1999049114)supported by the Provincial Science and Technology Programs of Henan(0524250042)Inner Mongolia(20020307)Shanxi(001065)Beijing(953500400)enterprises of Shaanxi Daqin Potassium Industry CorporationTongling Chemical Industry Group CorporationShanxi Ziguang Potassium Industry CorporationHenan Qianhe Mining Corporationthe Geological Survey of Tianjin
文摘Long-term research on key techniques of clean utilization of potassic rocks from over twenty localities has been performed to settle the shortage of soluble potassium resources in China. The results show that K-feldspar as the principal mineral enriched in potassium could be decomposed in the media of Ca（OH）_2, NaOH, KOH-H_2O solution via hydrothermal treatment, into tobermorite, hydroxylcancrinite, and kalsilite respectively. By further processing, these compounds are feasible for being as slow-release carrier of potassium nitrate, extracting alumina, and preparing farm-oriented fertilizers of potassium sulphate and nitrate. Correspondingly, the filtrate is KOH,（Na, K）_2SiO_3, and K_2SiO_3 solution, from which potassium carbonate, sulphate, nitrate, and phosphate could be easily fabricated. As NaO H and KOH are recycled in the processing chains by causticizing sodium and/or potassium metasilicate solutions, the hydrothermal alkaline techniques as developed in this research have several advantages as lower consumption of disposable mineral resources and energy, maximized utilization of potassic mineral resources, as well as clean productions etc. Based on the approaches presented in this paper, the technical system of efficiently utilizing insoluble potassium resources has been established. The hydrothermal alkaline methods are feasible to be industrialized on a large scale, thus resulting in decreasing imports of potash fertilizers, improving the pattern of potassium fertilizer consumption, and enhancing the supplying guarantee of potassium resource in China.
