混合碳酸稀土萃取分离工艺的改进与成品和半成品分析方法的建立

发布时间：2018-05-17 13:31

本文选题：碳酸稀土 + 萃取分离　；参考：《内蒙古大学》2017年硕士论文

【摘要】：本文针对内蒙古航天金峡化工有限责任公司年产5000吨混合碳酸稀土萃取分离生产线工艺现状及存在的主要问题,提出了对混合碳酸稀土萃取分离工艺技术中镧铈分组出口级数、铈镨分组出口设置等进行了工艺路线改进,优化了混合碳酸稀土萃取分离的工艺路线,提高了稀土分离产品的质量。同时,针对稀土分离后成品和半成品质量控制要求,改进了钐铕钆料液浓度的分析方法,开发了混合稀土料液中硫酸根的重量分析法,改进了镨钕氧化物中铝离子的ICP-AES检测方法,建立完善了稀土分离成品和半成品的分析方法。论文主要研究内容如下:1.内蒙古航天金峡化工有限责任公司(金峡化工)年产5000吨混合碳酸稀土萃取分离生产线镧铈分组现采用88级串级萃取分离工艺,该流程通常在第8级出口产生氯化镧料液,但是由于Na+、Ca2+、Mg2+等非稀土杂质含量高,导致氯化镧料液质量超标,不符合要求,导致浓缩工序料液结块,放料困难。基于此问题,通过实验测定每一级数稀土料液中稀土杂质和非稀土杂质的含量,提出将氯化镧料液在生产工艺流程中的停留时间延长,将氯化镧料液的出口级数由8级升为12级。通过该工艺流程的改进,使得氯化镧料液中非稀土杂质Na+的含量由0.37%降为0.23%,Ca2+由2%降为1.0%。同时,实现了浓缩过程中釜内物料高浓度下顺利放料,无堵塞现象,保证了 24小时浓缩一釜的生产进度,氯化镧浓缩产品的品位可达45%以上,较之前提高了 1-2%。2.金峡化工年产5000吨混合碳酸稀土萃取分离生产线110级串级萃取分离工艺流程中,由于萃取槽出口设置不合理,导致铈镨分离线出口产生的镧铈料液中Na+、Ca2+、Mg2+等非稀土杂质含量高,且以南方稀土矿为原料时镧铈配分达不到要求(镧占35%和铈占65%)。同时,还造成后续浓缩工序料液容易结块,放料困难。基于此问题,通过实验测定铈镨分离线各级数稀土料液中稀土杂质和非稀土杂质的含量,提出增加铈镨分离线料液出口,由原8和100料液两个出口改为8、22、100三个料液出口。通过该工艺改进和优化,使第22级料液出口产出的镧铈纯度得到很大提高,Na+、Ca2+、Mg2+等非稀土杂质含量大大降低,Na+由0.31%降为0.1%,Ca2+由1.8%降为0.8%。3.金峡化工年产5000吨混合碳酸稀土萃取分离生产线需要对钕钐分组第40级出口产生的钐铕钆料液浓度进行分析,通常直接采用国标容量法或重量法进行测定,但容量法在料液中铁含量高时误差大,超出允许范围;而重量法耗时长,影响生产效率。基于此问题,提出在钐铕钆料液浓度测定前增加前处理工序,通过添加草酸将钐铕钆沉淀,经充分洗涤除去铁杂质,利用硝酸和高氯酸将稀土沉淀转为钐铕钆料液,然后再采用容量法对其浓度进行测定。该分析方法缩短了料液分析时间,提高料液浓度测定的准确性,保证了生产效率。4.金峡化工年产5000吨混合碳酸稀土萃取分离生产线需要对生产过程中的镨钕料液、碳酸镨钕、镨钕氧化物中的Al3+进行测定,采用电感耦合等离子体原子发射光谱(ICP-AES)方法进行测定时,为了消除基体对铝的影响,配置标准溶液时需加入镨钕作为基体进行在峰校准,这种方法配置标液耗时长且消耗大量氧化镨和氧化钕基准试剂,因此急需优化分析测定方法,降低成本。为此我们对氧化镨钕中铝含量的测定方法进行了改进,主要将原来的在峰校正方法改成离峰校正,操作过程体现在铝测定的标准溶液的配置方法上。由此,改进了配置标准溶液的方法,省略烘干氧化镨和氧化钕步骤,通过仪器自动扣除镨钕背底峰值,简化了铝离子的检测步骤,为配置标准溶液节省了成本和时间。5.金峡化工年产5000吨混合碳酸稀土萃取分离生产线生产过程中需要对溶料过程产生的混合稀土料液中的硫酸根离子进行测定。通常采用分光光度法进行测定,该法需使用稳定剂稳定沉淀的硫酸根离子,由于稳定剂的变化导致测定结果不稳定,有时误差会较大。为解决这个问题,建立了利用重量法测定混合稀土料液中的硫酸根离子的方法,通过将稀土料液调至弱酸性,加入过量氯化钡溶液将稀土料液中的硫酸根离子生成硫酸钡沉淀,再经过滤、洗涤、烘干、称重后计算硫酸根离子的含量,达到准确测定混合稀土料液中硫酸根离子的目的。该法测定硫酸根离子的准确度和稳定性较分光光度法得到较大提高。
[Abstract]:In this paper, the present situation and main problems of the 5000 ton mixed rare earth extraction and separation production line in Inner Mongolia spaceflight golden gorge Chemical Co., Ltd. are presented, and the process route is improved and the mixing process is improved. The process route of extraction and separation of rare earth carbonate improves the quality of rare earth separation products. At the same time, in view of the quality control requirements of the finished product and the semi-finished product after the separation of rare earth, the analytical method of the concentration of samarium europium gadolinium solution is improved, the weight analysis method of sulphuric acid in the mixed rare earth solution is developed, and the ICP-AES detection of aluminum ions in the praseodymium and neodymium oxide is improved. The main research contents of the paper are as follows: 1. the lanthanum cerium group in the 5000 ton mixed rare earth extraction and separation production line of Inner Mongolia spaceflight golden gorge Chemical Co., Ltd. (Jin Xia chemical) is now used in class 88 cascade extraction and separation process, which is usually produced at the level of eighth level. Lanthanum chloride solution is produced, but the high content of non rare earth impurities, such as Na+, Ca2+ and Mg2+, leads to the high quality of lanthanum chloride solution, which does not meet the requirements, which leads to the agglomeration of the material liquid in the concentrating process, which is difficult. Based on this problem, the content of rare earth and non rare earth impurities in the rare earth solution of each series is determined by experiment. When the residence time in the production process is prolonged, the outlet series of lanthanum chloride liquid is raised from 8 to 12. Through the improvement of the process, the content of non rare earth impurity Na+ in lanthanum chloride is reduced from 0.37% to 0.23%, and Ca2+ is reduced from 2% to 1.0%.. The production schedule of concentrating one kettle for 24 hours is guaranteed, and the grade of lanthanum chloride concentrating products can be up to 45%. In the process of separating the 110 grade cascade extraction separation process of 1-2%.2. golden gorge with 5000 tons of mixed rare earth extraction and separation production line, the output of lanthanum produced by the export of cerium praseodymium separation line is caused by the unreasonable exportation of the extraction trough. The content of non rare earth impurities such as Na+, Ca2+ and Mg2+ in the cerium solution is high, and the coordination separation of lanthanum and cerium can not be reached when the south rare earth ore is used as raw material (lanthanum is 35% and cerium is 65%). At the same time, the material liquid in the subsequent concentration process is easy to caking and the discharge is difficult. Based on this problem, the rare earth impurities and the non dilute materials in the rare earth solution at all levels of the cerium praseodymium separation line are determined by experiments. The content of soil impurities is proposed to increase the export of cerium praseodymium separation line liquid, from the two exits of the original 8 and 100 materials to the 8,22100 three outlet. Through the improvement and optimization of the process, the purity of lanthanum and cerium produced in the export of twenty-second grade liquid is greatly improved, the content of non rare earth impurities such as Na+, Ca2+, Mg2+ and other non rare earth impurities are greatly reduced, Na+ from 0.31% to 0.1%, Ca2+ by 1.8 It is necessary to analyze the concentration of samarium and europium gadolinium solution produced in the fortieth stage of the neodymium samarium group by 5000 tons of 0.8%.3., which is usually directly adopted by the national standard volume method or gravimetric method, but the volumetric method has a high error and exceed the allowable range when the content of iron is high in the liquid, and the weight method is consumed. On the basis of this problem, it is proposed to increase the pretreatment process before the determination of the concentration of SM EU gadolinium solution. By adding oxalic acid to precipitate samarium europium gadolinium, the iron impurity is removed by full washing, and the rare earth precipitation is converted to samarium europium gadolinium solution by nitric acid and perchloric acid, and then the concentration is measured by capacity method. The accuracy of the determination of the concentration of the liquid is shortened, and the production efficiency of the 5000 ton mixed rare earth extraction and separation line of the annual production efficiency of.4. Jin Xia is guaranteed. The Al3+ of praseodymium and neodymium carbonate in the production process, the praseodymium neodymium carbonate and the praseodymium neodymium oxide are measured, and the inductively coupled plasma atomic emission spectrometry (ICP-AES) is used. In order to eliminate the influence of the matrix on the aluminum, the praseodymium and neodymium should be added as the matrix to calibrate the standard solution. This method configuring the standard solution is long and consumes a large amount of praseodymium oxide and neodymium oxide reference reagent. Therefore, it is urgent to optimize the analytical method and reduce the cost. Therefore, we have the aluminum content in the praseodymium oxide neodymium oxide. The method is improved, the original method of peak correction is changed to peak correction. The operation process is embodied in the method of allocation of standard solution for aluminium determination. Thus, the method of configuring the standard solution is improved, the steps of praseodymium oxide and neodymium oxide are omitted, the peak of the back bottom of the praseodymium and neodymium is automatically deducted by the instrument, and the detection of the aluminum ion is simplified. In the process of measuring the standard solution, the cost and time are saved, the 5000 tons of mixed rare earth extraction and separation production line of.5. Jin Xia chemical industry production process needs to be measured in the mixed rare-earth solution produced by the solution process. In order to solve this problem, a method for the determination of sulfate ion in mixed rare-earth solution is established by using the gravimetric method to determine the sulphuric acid root ion in the mixture of rare earth mixture. Barium sulfate is precipitated and then filtered, washed, dried and weighed, the content of the sulfate ion is calculated to achieve the purpose of accurate determination of the sulfate ion in the mixed rare-earth solution. The accuracy and stability of the determination of sulfate radical ions are greatly improved by this method.
【学位授予单位】：内蒙古大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ028.32;TQ133.3

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