(1. 天津大学 化工学院，精馏技术国家工程研究中心，天津 300350； 2. 中国科学院 过程工程研究所，湿法冶金清洁生产技术国家工程实验室，北京 100190)
摘 要: 采用水热法合成纳米花状的β-CrOOH，并用于钒(V5+)的吸附分离。在碱性体系中，合成的β-CrOOH比表面积为174.882 m2/g，孔体积为0.602 cm3/g。在65 ℃、pH = 4时，β-CrOOH对V5+的最大吸附容量可达到32.66 mg/g。吸附机理表明，β-CrOOH在吸附过程中其表面会释放出羟基以形成配位不饱和Cr6+活性中心，溶液中的钒酸根( )单体通过钒氧双键(V=O)与不饱和的Cr6+活性中心结合，形成内球型配位，从而吸附钒。在铬酸盐的清洁生产应用中，将β-CrOOH置于铬铁矿无钙焙烧中和液(Na2CrO4-NaVO3-H2O)中用来选择性分离V5+离子。结果表明，适量的β-CrOOH能将铬中和液中91.57%的钒有效脱除掉，铬几乎无吸附，从而实现钒铬的有效分离。
关键字: 羟基氧化铬；分离；铬酸盐溶液；钒；水热法；选择性吸附
（1. National Engineering Research Center of Distillation Technology, School of Chemical Engineering, Tianjin University, Tianjin 300350, China; 2. National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China）
Abstract:A guyanaite (β-CrOOH) with nanometer flower morphology synthesised by hydrothermal precipitation method and vanadate (V5+) ion adsorption on the β-CrOOH were investigated. In the alkaline system, the synthetic specific surface area of the β-CrOOH is 174.882 m2/g, the pore volum is 0.602 cm3/g. The β-CrOOH possesses the maximum V5+ ion adsorption capacity of 32.66 mg/g with pH=4 at 65 ℃. The adsorption mechanism results show that the β-CrOOH liberated surface hydroxyls to form coordinatively unsaturated Cr6+ centres, which further adsorbs V5+ ions through connecting mono-oxo, V=O terminal double bonds with oxygen of the Cr6+ centres. In the cleaner production application of chromate, the β-CrOOH is placed in the Na2CrO4-NaVO3-H2O solutions to selectively adsorb the V5+ ions, and 91.57% vanadium could be effectivly removed and Cr6+ is rarely adsorbed, realizing effective separation of vanadium and chromium.
Key words: β-CrOOH; separation; chromate solution; vanadium; hydrothermal method; selective adsorption
