Removal and utilization of calcite existed in scheelite by preparation of calcium sulfate whiskers  

作　　者：Guan Qingjun Sun Wei Hu Yuehua Guan Changping Yin Zhigang Zhang Chenhu 

机构地区：[1]School of Mineral Processing and Bioengineering, Central South University, Changsha 410083, China

出　　处：《International Journal of Mining Science and Technology》2017年第6期1005-1010,共6页矿业科学技术学报（英文版）

基　　金：provided by the National Key Technology R&D Programs from the Ministry of Science and Technology of China(No.2012BAB07B05);the Program of Introducing Talents of Discipline to Universities(Supported by the 111 Project,B14034);the Fundamental Research Funds for the Central Universities of Central South University(No.2016zzts104)

摘　　要：In order to eliminate the effect of calcite associated with scheelite on the scheelite flotation, hydrochloric acid was used to dissolve the calcite, and the soaking solution was used to prepare CaSO_4 whiskers by hydrothermal reaction with sulfuric acid at ambient pressure. First, the condition experiments of preparing CaSO_4 whiskers by using CaCl_2 and H_2SO_4 were carried out to optimize reaction parameters of the crystallization process. The optimal conditions were: at 102 ℃ reaction temperature, 0,5 mol/L reactant concentration and 60 min reaction time. Then based on the condition experiments and considering keeping acid concentration stable for achieving HCl recycling, Calcium sulfate whiskers with the average diameter of 1.41 μm and the average aspect ratio of 109 were prepared by the soaking solution after evaporating to half of its volume and 1.0 mol/L H_2SO_4 at 102 ℃ for 60 min: After ion exchange processing,the filtrate could be used as HCl in the process of HCl dissolution.In order to eliminate the effect of calcite associated with scheelite on the scheelite flotation, hydrochloric acid was used to dissolve the calcite, and the soaking solution was used to prepare CaSO_4 whiskers by hydrothermal reaction with sulfuric acid at ambient pressure. First, the condition experiments of preparing CaSO_4 whiskers by using CaCl_2 and H_2SO_4 were carried out to optimize reaction parameters of the crystallization process. The optimal conditions were: at 102 ℃ reaction temperature, 0,5 mol/L reactant concentration and 60 min reaction time. Then based on the condition experiments and considering keeping acid concentration stable for achieving HCl recycling, Calcium sulfate whiskers with the average diameter of 1.41 μm and the average aspect ratio of 109 were prepared by the soaking solution after evaporating to half of its volume and 1.0 mol/L H_2SO_4 at 102 ℃ for 60 min: After ion exchange processing,the filtrate could be used as HCl in the process of HCl dissolution.

关 键 词：Calcium SULFATE WHISKERS SCHEELITE CALCITE HCL HYDROTHERMAL reaction 

分 类 号：O784[理学—晶体学] TQ132.32[化学工程—无机化工]