摘要
含钒页岩是一种钒储量仅次于钒钛磁铁矿的重要矿物资源,其钒品位均较低,同时含有铝、铁、钙、镁、钼、镍等金属元素。采用常规酸性浸钒工艺产出的酸浸液中杂质元素众多,且目标金属钒浓度较低,从中分离富集钒难度较大,需采取选择性强的方法从中提取钒。首先对含钒页岩酸浸液的处理方法进行了归纳总结,对各种分离方法的优缺点进行比较分析;其次对选择性分离钒的萃取剂按照酸性磷类萃取剂、碱性胺类萃取剂、中性含磷萃取剂、螯合类萃取剂的分类进行对比分析;在各类萃取剂中,碱性胺类萃取剂在含钒页岩低酸浸出液分离钒中具有良好的应用前景,碱性胺类萃取剂将朝着兼顾高选择性的前提下,加入合适的添加剂或改性剂,改善有机相的操作性能,实现高效的方向发展。
Vanadium is an important strategic resource,which is widely used in iron and steel,metallurgy,chemical industry and other fields. The main vanadium-bearing minerals in China are vanadium-bearing shale and vanadium-titanium magnetite. Vanadiumbearing shale is a unique vanadium-bearing mineral resource in China,and its vanadium reserves are the second only to vanadium-titanium magnetite. It is widely distributed in Hunan,Hubei,Anhui,Jiangxi,Zhejiang and other provinces,and the grade of vanadium in vanadium-bearing shale varies greatly from region to region. The grade is mostly between 0.13% and 1.00%,and the grade is less than 1.00%. At the same time,it contains aluminum,iron,calcium,magnesium,molybdenum,nickel and other metal elements,and has high comprehensive utilization value. Due to the low vanadium grade of vanadium-bearing shale,the economic value of mining is low under the condition of immature technology,and the development of vanadium-bearing shale is less. With the mining consumption of vanadium-bearing mineral resources and the improvement and upgrading of technology,high-grade minerals are gradually difficult to meet the needs of development,and the comprehensive utilization value of vanadium-bearing shale is gradually reflected. At present,the main processes of extracting vanadium resources from vanadium-bearing shale are blank roasting-leaching process,additive roasting-leaching process,additive roasting-leaching agent leaching process and direct acid leaching process. Blank roasting-acid leaching process has poor adaptability to ore and low vanadium leaching rate;additive roasting-leaching process and additive roastingleaching process have better vanadium leaching rate,but the improper selection of additives in the roasting process will produce harmful gases and pollute the environment;the solution treated by direct acid leaching process has high acidity and high concentration of impurity ions,which makes it more difficult to purify and remove impurities in the follow-up solution. At present,the mainstream process is roasting-leaching process with additives,and the leaching process is mainly acid leaching. Using the conventional acid vanadium leaching process,there are a large number of impurity elements such as Al,Fe,Ca,Mg and Na in the acid leaching solution,and the concentration of vanadium is low,so it is difficult to separate and enrich vanadium from the acid leaching solution. In this paper,the present situation of the research on the separation and enrichment of vanadium from vanadium-bearing shale acid leaching solution was summarized,and the advantages and disadvantages of chemical precipitation,ion exchange,solvent extraction and some new selective separation methods were compared and analyzed. The results showed that the impurity removal effect of chemical precipitation method was general,the loss rate of vanadium was high,and the enrichment could not be achieved;the exchange efficiency of ion exchange method was low,and some ion exchange resins were expensive. The solvent extraction method had strong selectivity and high separation efficiency,and the new selective separation methods such as solvent impregnation resin and capacitive deionization technology were still in the stage of development and needed to be continuously improved. By comparison,it could be seen that the solvent extraction method had the advantages of high selectivity,high extraction efficiency and easy process,and had great advantages in purifying and enriching vanadium in vanadium-bearing shale acid leaching solution. Secondly,the extractants for selective separation of vanadium in solvent extraction were compared and analyzed according to the classification of acidic phosphorus extractants,alkaline amine extractants,neutral phosphorus extractants and chelating extractants. The results showed that acidic phosphorus extractants and alkaline amine extractants had good extraction effect of vanadium,while neutral phosphorus-containing extractants and chelating extractants were studied less because of the lack of extraction ability and high price. It was not suitable for purification and enrichment of vanadium in acid leaching solution of vanadium-bearing shale. Under the condition of good pH control,the acid phosphorus extractant had a good extraction rate of vanadium,but its selectivity was not good. Aluminum,iron and other elements in the solution would also be extracted into the organic phase in the process of vanadium extraction,and the separation coefficient of vanadium and impurities was low. Compared with acidic phosphorus extractant,alkaline amine extractant vanadium had excellent selective extraction effect,large separation coefficient from impurities,strong purification and enrichment ability,and had a good application prospect in the separation of vanadium from low acid leaching solution of vanadium-bearing shale. When extracting with alkaline amine extractant,vanadium and impurities were separated thoroughly,for example,the separation coefficients of ferrovanadium and vanadium aluminum were larger,but alkaline amine extractants were easy to produce emulsification,organic phase was mixed with water,not easy to separate phase,and poor phase separation performance,which had a great impact on the follow-up operation,resulting in low recovery of vanadium,non-recycling of organic phase and so on. In the future,this kind of extractant would develop in the direction of improving the operation performance of organic phase,avoiding organic phase emulsification,reducing extraction phase separation time and achieving high efficiency under the premise of high selectivity.
作者
赖永传
杨鑫龙
孙建之
尚鹤
高文成
温建康
Lai Yongchuan;Yang Xinlong;Sun Jianzhi;Shang He;Gao Wencheng;Wen Jiankang(National Engineering Laboratory of Biohydrometallurgy,GRINM Group Corporation Limited.Beijing 101407,China;GRINM Resources and Environment Tech.Co.,Lad.Beijing 101407,China;General Research Institutefor Nonferrous Metals,Beijing 100088,China;GRIMAT Engineering Institute Co.,Ldd.Beijing 101407,China)
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2022年第1期109-119,共11页
Chinese Journal of Rare Metals
基金
国家重点研发专项计划项目(2020YFC1909703)
有研科技集团有限公司青年基金项目资助。
关键词
含钒页岩
酸浸液
溶剂萃取法
碱性胺类萃取剂
选择性萃取
vanadium-bearing shale
acid leaching solution
solvent extraction
alkaline amine extractant
selective extraction
