摘要
以湖北某地石煤为原料,用硫酸+氟化钙+二氧化锰体系直接浸出石煤原矿中的钒,考察了二氧化锰用量、氟化钙用量、硫酸浓度、浸出温度、液固比以及浸出时间等因素对钒浸出率的影响。试验结果表明,氟化钙和二氧化锰用量分别为原矿质量的6%和0.5%、硫酸浓度18%、液固比2.0m L/g、浸出温度95℃、浸出时间6h的条件下钒的浸出率可达84.94%。结合浸出液ICP分析、浸出渣XRD分析和FTIR分析及SEM-EDS分析、热力学分析可知,浸出过程中,氟化物可使含钒矿物得到一定程度的结构破坏,增加了含钒矿物的裸露表面,而适量二氧化锰的引入有利于云母结构的破坏,并且强化了裸露表面上低价钒向高价钒的转化,增强了钒的释放,因此提高了钒的浸出率;另外,适量二氧化锰可促使三氟化铁更容易形成,降低铁的浸出率。
Tests on direct acid leaching vanadium from stone coal in Hubei province with sulfuric acid, calcium fluoride and manganese dioxide were carried out. The influence of manganese dioxide amount, dosage of calcium fluoride, concentration of sulfuric acid, leaching temperature, liquid to solid ratio and leaching time on leaching rate of vanadium was observed individually. It showed that leaching rate of vanadium can exceed 84.94% under the conditions that the dosage of calcium fluoride and manganese dioxide is 6% and 0.5% of raw ore quality respectively, the sulfuric acid concentration is 18%, the liquid to solid ratio is 2.0mL/g, the leaching temperature remains at 95℃, the leaching time is 6h. Combined with ICP analysis of leaching solution, the XRD and FTIR and SEM-EDS analysis of leaching residue, and thermodynamics, results showed that in leaching process the fluoride can cause acertain degree of structural damage of vanadium containing minerals, and increase the exposed surfaces of vanadium containing minerals, while the appropriate amount of manganese dioxide introduced was beneficial to the destruction of mica structure, and strengthen the transformation of low valence vanadium to high valence vanadium on the exposed surface, which enhance the release of vanadium. Therefore, leaching rate of vanadium was improved. In addition, appropriate amotmt of manganese dioxide can make trivalent iron fluoride more easily to form. and reduce the leaching rate of iron.
作者
陈放
张一敏
黄晶
刘涛
薛楠楠
CHENFangl, ZHANG Yimin HUANG Jing LIU Tao XUE Nannan(School of Resource and Environment Engineering, Wuhan University of Science and Technology, Wuhan 430081, Hubei, China Hubei Provincial Engineering Technology Research Center of High Efficient Cleaning Utilization for Shale Vanadium Resource, Wuhan 430081, Hubei, China Hubei Provincial Collaborative Innovation Center for High Efficient Utilization ofVanadium Resources, Wu_han430081, Hubei, China HubeiCollaborativeltmovationCenter of Application for Advanced Steels, Wuhan 430081, Hubei, China)
出处
《化工进展》
EI
CAS
CSCD
北大核心
2017年第3期1126-1133,共8页
Chemical Industry and Engineering Progress
基金
国家自然科学基金青年科学基金项目(51404174
51474162)
关键词
石煤提钒
氟化钙
二氧化锰
直接浸出
extracting vanadium from stone coal
calcium fluoride
manganese dioxide
direct leaching
