Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigate...Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigated, such as grinding fineness, the amount of sulfuric acid and fluoride salt, reaction time and temperature, etc. Meanwhile, the effects of various factors on the formation of soluble potassium and phosphate were also discussed. The reaction products and residues were determined by X-ray diffraction（XRD）, scanning electron microscopic（SEM） analysis and other means. The results showed that the dissolution rates of potassium and phosphorus were 70wt% and 93.7wt%, respectively, under the conditions of a grain size of 95.64wt% lessthan 0.074 mm, 9.78 g·g^（-1） sulfuric acid, 0.5 g·g^（-1） ammonium fluoride, 160 ℃ and a reaction time of 2h. The thermodynamic and chemical reaction mechanism was revealed that the primary reaction could be completed spontaneously in a temperature range of 298-433 K. The increase of reaction temperature had an important influence on ion exchange reaction, which was more conducive to the spontaneous process. The research will open up a new way for efficient use of potassium ore resources.展开更多
A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is...A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.展开更多
基金Funded by the National Natural Science Fundation of China(51274158)the National Twelfth Five-Year Plan for Scientific and Technological Support(2013BAE04B03)the Scientific and Technological Support Project of Hubei Province(2015BCA251)
文摘Potassium and phosphate were extracted at low temperature by acid hydrolysis process to decompose a new type of associated phosphorus and potassium ore. The main factors affecting the dissolution rate were investigated, such as grinding fineness, the amount of sulfuric acid and fluoride salt, reaction time and temperature, etc. Meanwhile, the effects of various factors on the formation of soluble potassium and phosphate were also discussed. The reaction products and residues were determined by X-ray diffraction（XRD）, scanning electron microscopic（SEM） analysis and other means. The results showed that the dissolution rates of potassium and phosphorus were 70wt% and 93.7wt%, respectively, under the conditions of a grain size of 95.64wt% lessthan 0.074 mm, 9.78 g·g^（-1） sulfuric acid, 0.5 g·g^（-1） ammonium fluoride, 160 ℃ and a reaction time of 2h. The thermodynamic and chemical reaction mechanism was revealed that the primary reaction could be completed spontaneously in a temperature range of 298-433 K. The increase of reaction temperature had an important influence on ion exchange reaction, which was more conducive to the spontaneous process. The research will open up a new way for efficient use of potassium ore resources.
基金This study was performed under the China Geological Survey(Grant no.DD20190172)the Sino Probe(Grant no.2017YFC0602806)。
文摘A new type of polyhalite potassium ore(NTPPO) was found in the Lower Triassic Jialingjiang Formation, NE Sichuan Basin, SW China. It is water soluble, therefore can be exploited using the water-solution method, and is of great potential of economic value and research significance. Based on cores, thin sections, energy spectrum and SEM analyses, its microfeatures, macrofeatures and origin are discussed, and a genetic model is established to provide a scientific basis for future evaluation, prediction and exploration of potassium ore in the Sichuan Basin. It is proposed that the NTPPO was caused by storm activities:(1) the storm broke the original sedimentary polyhalite–gypsum beds, whose fragments were transported into the salt basin with high content of K+ and Mg2+;(2) in the basin, the polyhalite continued to be formed from gypsum by metasomatism with K-and Mg-rich brine;(3) during diagenesis, under high temperature and high pressure, K–Mg-rich brine from halite continued to replace anhydrite(or gypsum) to form polyhalite.
