Fractional Leaching of Vanadium and Tungsten from Spent SCR Catalyst with Oxalic Acid
MI Qiaomin1,2, YAO Junxuan1,2, WANG Bing1,2, CHANG Liping1,2, BAO Weiren1,2, ZHANG Zhihua3, WANG Jiancheng1,2
1. State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan 030024, China;
2. Key Laboratory of Coal Science and Technology Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China;
3. Shanxi Puli Environmental Engineering Company Limited, Jinzhong 030600, China
Abstract：Spent catalysts of selective catalytic reduction (SCR) contain valuable metals such as vanadium, tungsten and titanium. To maximize the recovery of vanadium and tungsten resources, the effects of oxalic acid concentration, leaching temperature, liquid-solid ratio and leaching time on vanadium and tungsten leaching efficiency were systematically investigated. The leaching mechanism was analyzed by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The spent SCR catalyst was leached directly with oxalic acid, the vanadium leaching efficiency was 76.95%, the tungsten and titanium leaching efficiency were only 5.31% and 0.22%, thus vanadium was leached. After roasting, the filter residue was leached with oxalic acid, and the tungsten leaching efficiency was 56.70%, vanadium and titanium leaching efficiency were only 16.36% and 0.12%, thus tungsten was leached, and the main component of the filter residue was anatase-type TiO2. The process achieved the fractional leaching of spent SCR catalyst, by vanadium and tungsten were leached in different steps, which avoided the difficulty of the subsequent separation of vanadium and tungsten, simplified the subsequent treatment work and reduced the secondary pollution.
MI Qiaomin,YAO Junxuan,WANG Bing et al. Fractional Leaching of Vanadium and Tungsten from Spent SCR Catalyst with Oxalic Acid[J]. Chemical Reaction Engineering and Technology, 2023, 39(6): 525-534.
