Zhang Xingran, Li Gang, Wu Jun, Xiong Neng, Quan Xuejun
School of Chemistry and Chemical Engineering, Chongqing University of Technology, Chongqing 400054, P. R. China.
ACS Omega. 2020 Jul 27;5(31):19633-19638. doi: 10.1021/acsomega.0c02194. eCollection 2020 Aug 11.
The efficacious treatment and resource utilization of the chromite ore processing residue (COPR) is important for chromate salt production. In this study, the leaching of valuable elements from the waste COPR was investigated. X-ray diffraction (XRD) analysis showed that the COPR mainly contained periclase (MgCrO), magnesiochromite ((Fe, Mg) (Cr, Fe)O), Fe (Cr, Al)O, and MgFeAlO. The optimum parameters for COPR leaching were as follows: mechanical ball-milling time of 120 min, sulfuric acid concentration (w/w % HSO) of 60%, reaction temperature () of 403 K, liquid-solid ratio (L/S) of 8 mL/g, and reaction time () of 6 h. Under these conditions, the valuable components such as Fe, Al, and Cr were extracted with an ideal leaching efficiency of 94.8, 75.1, and 76%, respectively. The results of the leaching kinetics analysis indicated that the leaching of Fe and Cr from the COPR was controlled by a surface chemical reaction, and the leaching of Al was controlled by diffusion through a product layer. The apparent activation energy of the leaching of Fe, Cr, and Al was calculated to be 23.03, 44.15, and 17.54 kJ/mol, respectively. It is believed that this approach has potential applications for the chromate salt industry because of its advantage of ideal leaching efficiency.
铬铁矿加工残渣（COPR）的有效处理和资源利用对铬盐生产至关重要。本研究对从废弃COPR中浸出有价元素进行了调查。X射线衍射（XRD）分析表明，COPR主要包含方镁石（MgCrO）、镁铬铁矿（(Fe,Mg)(Cr,Fe)O）、Fe(Cr,Al)O和MgFeAlO。COPR浸出的最佳参数如下：机械球磨时间120分钟、硫酸浓度（w/w%H₂SO₄）60%、反应温度（）403K、液固比（L/S）8mL/g、反应时间（）6小时。在这些条件下，Fe、Al和Cr等有价成分被提取出来，浸出效率理想，分别为94.8%、75.1%和76%。浸出动力学分析结果表明，从COPR中浸出Fe和Cr受表面化学反应控制，浸出Al受通过产物层的扩散控制。计算得出Fe、Cr和Al浸出的表观活化能分别为23.03、44.15和17.54kJ/mol。由于其浸出效率理想的优势，相信这种方法在铬盐行业有潜在应用。
