Le Van-Giang, Vu Chi-Thanh, Shih Yu-Jen, Huang Yao-Hui
Department of Chemical Engineering, National Cheng Kung University Tainan 71710 Taiwan
Civil and Environmental Engineering Department, The University of Alabama in Huntsville Huntsville AL 35899 USA.
RSC Adv. 2019 Aug 13;9(44):25303-25308. doi: 10.1039/c9ra03331a.
Ruthenium (Ru) is a rare-earth metal, which is employed widely in metal-processing industries. This study recovered Ru from the wastewater of an IC foundry by cementation using metallic aluminum (Al) powder as the sacrificial agent. Ru ions were efficiently reduced to the metal and coagulated with the derived aluminum hydroxide flocs. Experimental parameters included the particle size of Al, molar ratio of Al to Ru, initial Ru concentration and operation temperature. The recovery rate reached 99% under these conditions: particle size Al powder = 88-128 μm, Al/Ru molar ratio = 2.0, initial Ru = 200 mg L, temperature = 338.16 K, reaction time = 120 min, stirring speed = 150 rpm. The cemented Ru over Al powder was spherical with a rough surface. Kinetic modelling suggested that the diffusion of Ru through the ash layer of Al powder controlled the reaction rate with an activation energy of 40.75 kJ mol. A brief cost analysis demonstrated that the cementation of Ru yielded a profit of $0.180 per 0.1 m-wastewater.
钌（Ru）是一种稀土金属，在金属加工行业中广泛应用。本研究以金属铝（Al）粉作为牺牲剂，通过置换沉淀法从一家集成电路铸造厂的废水中回收钌。钌离子被有效地还原为金属，并与生成的氢氧化铝絮体凝聚。实验参数包括铝的粒径、铝与钌的摩尔比、初始钌浓度和操作温度。在以下条件下回收率达到99%：铝粉粒径 = 88 - 128 μm，铝/钌摩尔比 = 2.0，初始钌浓度 = 200 mg/L，温度 = 338.16 K，反应时间 = 120 min，搅拌速度 = 150 rpm。附着在铝粉上的钌呈球形，表面粗糙。动力学模型表明，钌通过铝粉灰层的扩散控制了反应速率，活化能为40.75 kJ/mol。简要的成本分析表明，每处理0.1立方米废水，钌的置换沉淀法可产生0.180美元的利润。
