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doi:10.

3969/j.issn.1007-7545.2019.04.008 富集渣中铪的TBP萃取分离研究 许万祥1,高凯1,郭瑞1,李进1,周严1,张卜升2 (1.西安瑞鑫科金属材料有限责任公司,西安 710016;

2.西北有色研究院,西安 710016) 摘要:以铪钛富集渣为原料,经硝酸溶解后采用TBP进行铪的萃取分离试验,主要考察铪钛质量浓度、有机相初始酸度、萃取时间、水相初始酸度、相比等对铪钛分离的影响,同时进行了不同浓度硝酸洗涤试验,以萃取和洗涤得到数据为基础进行了分馏萃取理论级数的计算.结果表明,最优萃取条件为:铪钛总质量浓度2.8 g/L、有机相初始酸度3.1 mol/L、萃取时间6 min、水相初始酸度6.5 mol/L、相比1U1,铪、钛萃取率分别为84.8%和5.1%,铪、钛分配比分别为5.6和0.054,萃取分离系数βHf/Ti=104.选用10 mol/L硝酸洗涤TBP载铪有机相,得到洗涤β'

Hf/Ti=105,基本与βHf/Ti保持一致,经计算分馏萃取分离铪钛需要萃取级数3级,洗涤级数4级. 关键词:铪钛富集渣;

TBP;

萃取;

洗涤 中图分类号:TF803.2+3;

TF84 文献标志码:A 文章编号:1007-7545(2019)04-0000-00 Study on Separation of Hafnium from Enriched Slag with TBP Extraction XU Wan-xiang1, GAO Kai1, GUO Rui, LI Jin1, ZHOU Yan1, ZHANG Bo-sheng2 (1. Xi'

an Rarealloys Co., Ltd., Xi'

an 710016, China;

2. Northwest Institute for Nonferrous Metal Research, Xi'

an 710016, China) Abstract:Separation test of Hf by extraction with TBP from nitric acid dissolved Hf &

Ti enriched slag was conducted. Effects of Hf &

Ti mass concentration, initial acidity of organic phase, extraction time, initial acidity of water phase, and phase ratio of organic phase to aqueous (O/A) on separation of Hf and Ti were investigated. Washing tests with different concentration of nitric acid were carried out. Theory stage of fractional extraction was calculated based on data of extraction and washing. The results show that extraction rate of Hf and Ti is 84.8% and 5.1% respectively, distribution ratio of Hf and Ti is 5.6 and 0.054, and extraction separation coefficient βHf/Ti is

104 under the optimum conditions including total mass concentration of Hf &

Ti of 2.8 g/L, initial acidity of organic phase of 3.1 mol/L, extraction time of

6 min, initial acidity of water phase of 6.5 mol/L, and O/A=1/1. Washing separation coefficient β'

Hf/Ti of TBP organic phase loaded with Hf with

10 mol/L nitric acid is 105, which is basically consistent with βHf/Ti. Extraction stage is three and washing stage is four to separate Hf and Ti by fractionation extraction after calculation. Key words:hafnium &

titanium enriched slag;

TBP;

extraction;

washing 铪作为一种战略金属,具有耐高温、抗腐蚀、抗氧化、易加工、快速吸热和放热等性能,被用作原子能材料、合金材料、耐高温材料、电子材料等[1].但由于其用途特殊,提取方法复杂,产量较少,价格昂贵,加之熔点较高,因而被称为稀有难熔金属[2].我国铪储量较贫乏,从废合金料中提取分离铪的研究具有重要意义. 钛、铪和锆同属第IV B族过渡系元素,具有相同的外层电子结构,彼此性质相似.自然界中铪多是伴生在锆英石中,锆和铪的分离技术是制备核级锆和铪的关键[3-6],从锆英石中分离提纯并制备原子能级铪的湿法分离工艺研究较多.但针对含铪合金废料,由于其所含元素种类繁多,铪的分离提纯工艺研究相对较少.本文以含铪合金废料经预处理得到的铪钛富集渣为原料,经硝酸溶解,采用TBP-HNO3体系进行铪钛萃取分离研究.