(1. 天津大學(xué) 化工學(xué)院，精餾技術(shù)國家工程研究中心，天津 300350； 2. 中國科學(xué)院 過程工程研究所，濕法冶金清潔生產(chǎn)技術(shù)國家工程實驗室，北京 100190)
摘 要: 采用水熱法合成納米花狀的β-CrOOH，并用于釩(V5+)的吸附分離。在堿性體系中，合成的β-CrOOH比表面積為174.882 m2/g，孔體積為0.602 cm3/g。在65 ℃、pH = 4時，β-CrOOH對V5+的最大吸附容量可達(dá)到32.66 mg/g。吸附機理表明，β-CrOOH在吸附過程中其表面會釋放出羥基以形成配位不飽和Cr6+活性中心，溶液中的釩酸根( )單體通過釩氧雙鍵(V=O)與不飽和的Cr6+活性中心結(jié)合，形成內(nèi)球型配位，從而吸附釩。在鉻酸鹽的清潔生產(chǎn)應(yīng)用中，將β-CrOOH置于鉻鐵礦無鈣焙燒中和液(Na2CrO4-NaVO3-H2O)中用來選擇性分離V5+離子。結(jié)果表明，適量的β-CrOOH能將鉻中和液中91.57%的釩有效脫除掉，鉻幾乎無吸附，從而實現(xiàn)釩鉻的有效分離。
關(guān)鍵字: 羥基氧化鉻；分離；鉻酸鹽溶液；釩；水熱法；選擇性吸附
（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
