Efficiency Optimization of Pharmaceutical Wastewater Treatment by a Microwave-Assisted Fenton-Like Process Using Special Supported Catalysts

摘要

The efficiency of a microwave-assisted Fenton-like process using special supported catalysts was evaluated using total organic carbon (TOC) removal from pharmaceutical wastewater. No acidification was required. The highest level of TOC removal efficiency from wastewater achieved was 65.88%. Moreover, the maximum number of consecutive uses with high activity was four. Under optimal conditions, the influent value of BOD5/COD was 0.25, and the effluent value of BOD5/COD was elevated to 0.40. In addition, colour was completely removed. This efficiency was compared with the same MW-Fenton-like process using common supported catalysts, where the highest achieved TOC removal efficiency from wastewater was 39.25%, the colour of the wastewater decreased from 50 to 20, and the value of BOD5/COD was elevated from 0.25 to 0.34. The maximum number of consecutive high activity uses was two. This advanced performance was attributed to no presence of copper carbonate or cerium carbonate on the surface of special supported catalysts. The preparation method for these catalysts combined the merits of the isometric impregnation method with some new improvements. Its advantages include high-efficiency performance, short preparation time, low reagent usage (cupric nitrate 3.6 g, cerium nitrate 1.2 g, ammonia 1 mL), and reusability. The properties of the catalyst with the most efficient performance were characterized by determining surface particle size, the relative amount of active components and promoters, and the stable crystal form of the active components.