Non-thermal plasma-enhanced low-temperature catalytic desulfurization of electrolytic aluminum flue gas by CuO-ZrSnO4: experimental and numerical analysis

Synthesis and Optimization of Foam Copper-Based CoMnOx@Co3O4/CF Catalyst: Achieving Efficient Catalytic Oxidation of Paraxylene

This study successfully developed a foam copper (CF)-based CoMnOx@Co3O4/CF composite catalyst, achieving efficient thermal catalytic oxidation of paraxylene through multifactor optimization of synthesis conditions. At a Co:Mn molar ratio of 2:1 and a calcination temperature of 450 °C, the catalyst exhibited outstanding catalytic performance, with a T90 temperature as low as 246 °C, significantly lower than that of catalysts synthesized under other conditions. Additionally, BET, XPS, Raman, EPR, and H2-TPR test results indicate that the catalyst possesses a high specific surface area, abundant oxygen vacancies, a distribution of multivalent Co and Mn species, and a lower hydrogen reduction temperature, all of which contribute to the high catalytic activity of CoMnOx@Co3O4/CF. Furthermore, in situ DRIFTS confirmed that the oxidation of paraxylene on CoMnOx@Co3O4/CF follows the Mars-Van Krevelen (MvK) mechanism. The proposed reaction pathway begins with the oxidation of the methyl group on paraxylene, followed by the opening of the benzene ring and further oxidation to CO2 and H2O. The innovative structural design and excellent catalytic performance of this catalyst provide new insights and solutions for the industrial treatment of VOCs.

The Removal of CH4 and NOx from Marine LNG Engine Exhaust by NTP Combined with Catalyst: A Review

Compared to diesel, liquefied natural gas (LNG), often used as an alternative fuel for marine engines, comes with significant advantages in reducing emissions of particulate matter (PM), SO_x, CO₂, and other pollutants. Promoting the use of LNG is of great significance for achieving carbon peaking and neutrality worldwide, as well as improving the energy structure. However, compared to diesel engines, medium- and high-speed marine LNG engines may produce higher methane (CH₄) emissions and also have nitrogen oxide (NO_x) emission issues. For the removal of CH₄ and NO_x from the exhaust of marine LNG engines, the traditional technical route of combining a methane oxidation catalyst (MOC) and an HN₃ selective catalytic reduction system (NH₃-SCR) will face problems, such as low conversion efficiency and high operation cost. In view of this, the technology of non-thermal plasma (NTP) combined with CH₄-SCR is proposed. However, the synergistic mechanism between NTP and catalysts is still unclear, which limits the optimization of an NTP-CH₄-SCR system. This article summarizes the synergistic mechanism of NTP and catalysts in the integrated treatment process of CH₄ and NO_x, including experimental analysis and numerical simulation. And the relevant impact parameters (such as electrode diameter, electrode shape, electrode material, and barrier material, etc.) of NTP reactor energy optimization are discussed. The work of this paper is of great significance for guiding the high-efficiency removal of CH₄ and NO_x for an NTP-CH₄-SCR system.

Chlorobenzene Removal Using DBD Coupled with CuO/γ-Al2O3 Catalyst

The removal of chlorobenzene using a dielectric barrier discharge (DBD) reactor coupled with CuO/γ-Al2O3 catalysts was investigated in this paper. The coupling of CuO enhanced the chlorobenzene degradation and complete oxidation ability of the DBD reactor, especially under low voltage conditions. The characterization of catalyst was carried out to understand the interaction between catalyst and plasma discharge. The effects of flow rate and discharge power on the degradation of chlorobenzene and the interaction between these parameters were analyzed using the response surface model (RSM). The analysis of variance was applied to evaluate the significance of the independent variables and their interactions. The results show that the interactions between flow rate and discharge power are not negligible for the degradation of chlorobenzene. Moreover, based on the analysis of byproducts, 4-chlorophenol was discriminated as the important intermediate of chlorobenzene degradation, and the speculative decomposition mechanism of chlorobenzene is explored.