Enhancing the catalytic desulfurization capacity of CuO-LaCoO3 using two dielectric barrier discharge configurations

Abstract

Developing efficient and economical methods to treat low concentrations of sulfur dioxide, which is commonly found in electrolytic aluminum flue gas and is typically emitted directly to the atmosphere without treatment, is an important objective. In this study, we examined the desulfurization efficiencies of CuO-LaCoO3 catalysts in two of the most common catalytic dielectric barrier discharge (DBD) enhancement layouts, namely the in-plasma-catalysis (IPC) and post-plasma-catalysis (PPC) configurations, for the first time. The results suggested a 160–266% enhancement in desulfurization efficiency can be reached in PPC configurations compared to the catalyst-only setup. More aggressively, 100% SO2 removal efficiency can be reached even at room temperature and pressure in IPC configuration if sufficient SIE (2486 J/L) was supplied. Among tested LaCoO3 catalysts, The groups doped with 15% Cu showed the best catalytic activity and excellent ozone suppression ability. The catalysts before and after the enhancement were analyzed and compared by N2-adsorption, SEM, XPS, XRD. The result suggested that discharge will increase the surface area of the catalyst from 31.81 to 155.43 (m2/g) and the proportion of Cu1+ without affecting the main crystalline structure ((Cu0.3Co0.7)Co2O4). Indicating the surface area and the REDOX capacity of catalyst are the main factors affecting the enhancement process. The change of intermediate and free radicals inside the reactor was also revealed by spectroscopy and numerical simulation.