Catalytic Removal of NOx on Ceramic Foam-Supported ZnO and TiO 2 Nanorods Ornamented with W and V Oxides.

Energy consumption steadily increases and energy production is associated with many environmental risks, e.g., generating the largest share of greenhouse gas emissions. The primary gas pollution concern is CO₂, CH₄, and nitrogen oxides (NOx). Environmental catalysis plays a pivotal role in NOx mitigation (DeNOx). This study investigated, for the first time, a collection of ceramic foams as potential catalyst support for selective catalytic NOx reduction (SCR). Ceramic foams could be an attractive support option for NOx removal. However, we should functionalize the surface of raw foams for such applications. A library of ceramic SiC, Al₂O₃, and ZrO₂ foams ornamented with nanorod ZnO and TiO₂ as W and V oxide support was obtained for the first time. We characterized the surface layer coating structure using the XPS, XRF and SEM, and TEM microscopy to optimize the W to V molar ratio and examine NO₂ mitigation as the SCR model, which was tested only very rarely. Comparing TiO₂ and ZnO systems reveals that the SCR conversion on ZnO appeared superior vs. the conversion on TiO₂, while the SiC-supported catalysts were less efficient than Al₂O₃ and ZrO₂-supported catalysts. The energy bands in optical spectra correlate with the observed activity rank. [ABSTRACT FROM AUTHOR]