氯化铝低温氯化法五氧化二钒提纯工艺研究

发布时间：2018-01-12 03:03

本文关键词：氯化铝低温氯化法五氧化二钒提纯工艺研究　出处：《中国科学院大学(中国科学院过程工程研究所)》2017年硕士论文　论文类型：学位论文

【摘要】：随着科技的不断进步,全钒液流电池、钒铝合金、锂电池以及催化剂等众多领域对高纯度五氧化二钒产品的需求量越来越大。高纯五氧化二钒的传统制备工艺大都停留在实验室研究阶段,面临着成本高、流程长、污染重、产品纯度低等问题,高纯五氧化二钒产品的低成本短流程清洁制备技术已成为钒化工行业的研究热点。本论文提出了一种通过无水氯化铝低温氯化分离工业级五氧化二钒产品中铁、铝、硅等杂质进而提纯并制备高纯五氧化二钒的新方法。首先,通过理论分析和探索实验确定了原则工艺流程;然后,系统研究了氯化反应的工艺条件和反应机理,以及氯化反应所得三氯氧钒中间体氨解过程中各因素对沉钒率和产品纯度的影响规律,并制备得到了五氧化二钒高纯产品;最后,进一步拓展了原料范围,选用三种不同的含钒原料对整体流程进行了验证。本论文在以下几方面取得了创新结果:(1)在热力学计算、物性分析及探索实验的基础上,确定了无水氯化铝低温氯化法制备高纯五氧化二钒新工艺的整体流程。研究结果表明,无水氯化铝与五氧化二钒之间的氯化反应在低温下可行,且结合各杂质氯化物的物化性质分析,确定此氯化反应对实现原料中钒与其他杂质的分离具备有利作用。反应温度为160℃C时,氯化反应发生并生成三氯氧钒中间体,中间体经过氨解煅烧过程制备出高纯V205。(2)系统研究了反应温度、原料配比、添加剂用量等因素对氯化反应的影响规律,确定了较适宜的氯化反应工艺条件,并借助TG-DSC、SEM、EDS等手段分析了氯化反应的机理。在反应温度为170℃、无水氯化铝与原料中五氧化二钒的化学计量比为3:1、氯化钠添加量x=nAlCl3/(nAlCl3+mNaCl)=0.6,且添加氯化钠后,反应时间可缩短到1h,三氯氧钒产品收率最高可达83.35%,反应产物纯度≥99.95%。氯化反应过程中有中间体AlOCl生成,最终A1C13全部转化成A1203。(3)研究了氨解过程各工艺参数对五氧化二钒产品纯度和沉钒率的影响规律,确定了较适宜的氨解工艺参数。在钒浓度介于13.4～68.8g/L之间、氨解温度为35℃C、加氨系数为0.8～1.0、搅拌强度为15 r/s时,氨解反应过程钒收率最高。'借助ICP、XRD、XRF、XPS等手段,对五氧化二钒产品的纯度及表面元素化学计量比进行了详细的分析,确定制备的五氧化二钒产品纯度≥99.97%。(4)分别以钒渣钠化提钒工艺生产的工业级五氧化二钒(96.487%)、石煤提钒工艺生产的工业五氧化二钒(96.675%)以及钒渣(25.46%V205)为原料,采用低温氯化法工艺,制得了纯度分别为≥99.84%、≥99.97%、≥99.70%的五氧化二钒产品,为含钒原料氯化提钒的研究提供了新思路。
[Abstract]:With the continuous progress of science and technology, VRB, vanadium Aluminum Alloy, many areas of the lithium battery and the catalyst great demands for high purity five of two vanadium products. The traditional preparation of high purity five of two vanadium production process mostly stay in the laboratory stage, facing a high cost, long process, heavy pollution problems, low product purity, low cost clean short process for preparing high purity five of two vanadium vanadium products has become a research hotspot in the chemical industry. This paper presents a kind of low temperature chloride anhydrous aluminum chloride by separation of industrial grade five of two vanadium products of iron, aluminum, silicon and other impurities and purification method preparation of high purity and five of two vanadium. Firstly, through theoretical analysis and exploration of experiment to determine the principle process; then, process conditions of chlorination reaction system and reaction mechanism, and the reaction to three vanadium oxychloride Between the ammonolysis of factors in influence of precipitation rate and product purity, and prepared five of two vanadium high purity products; finally, to further expand the range of raw materials, selected three kinds of whole process was proved vanadium containing raw materials. This paper has made the innovation results in the following aspects: (1) in the thermodynamic calculation, physical analysis and exploration based on the experiment, the whole process of new technology of low temperature aluminum chloride anhydrous chloride prepared by high purity five of two vanadium. The results show that the reaction between chloride and anhydrous aluminium chloride and five of two vanadium at low temperature and is feasible. Combined with the analysis of physicochemical properties of the impurities of chloride, the reaction of chloride determination of separation of vanadium in raw material and other impurities have beneficial effects. The reaction temperature is 160 DEG C, chloride reaction and generate three vanadium oxychloride intermediates, intermediates by aminolysis of calcined Burning process of preparing high pure V205. (2) system of reaction temperature, raw material ratio, effect of additive dosage on the chlorination reaction, the chlorination of determining suitable process conditions, and with the help of TG-DSC, SEM, EDS and other means of analysis of the mechanism of chlorination reaction. The reaction temperature is 170 DEG C, the stoichiometry of anhydrous aluminum chloride and raw materials in five of two vanadium ratio was 3:1, the adding amount of sodium chloride x=nAlCl3/ (nAlCl3+mNaCl) =0.6, and after the addition of sodium chloride, the reaction time can be shortened to 1H, three vanadium oxychloride products yield up to 83.35%, with intermediate product purity AlOCl generation reaction over 99.95%. chlorination reaction process finally, A1C13 into A1203. (3) studied the aminolysis process parameters on the five of two vanadium product purity and precipitation rate were investigated, to determine the optimum solution of ammonia process parameters. In vanadium concentration from 13.4 to 68.8g/L, Ammonia solution temperature of 35 DEG C, ammonia coefficient is 0.8 ~ 1, the stirring intensity is 15 r/s, ammonolysis process of vanadium yield. With the help of ICP, XRD, XRF, XPS and other means of purity and surface elements of stoichiometric five of two vanadium products than the detailed analysis, to determine the five oxidation the preparation of two vanadium product purity not less than 99.97%. (4) respectively in vanadium slag sodium extraction industrial grade five vanadium oxide production of two vanadium (96.487%), stone coal extraction industry five vanadium oxide production process of vanadium and vanadium slag is two (96.675%) (25.46%V205) as raw materials by low temperature chlorination process, prepared the purity was more than 99.84%, more than 99.97%, five more than 99.70% of two vanadium oxidation products, provides a new idea for raw materials containing vanadium vanadium chloride is studied.

【学位授予单位】：中国科学院大学(中国科学院过程工程研究所)
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TQ135.11

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