Efficient mineralization of nitrogen-containing aromatic compounds through catalytic wet peroxidation over a CeO2/SBA-15 catalyst

Abstract

The present study investigated the catalytic performance of a CeO₂/SBA-15 catalyst for the mineralization of nitrogenous aromatic compounds, specifically picoline and aniline, through the catalytic wet peroxidation (CWPO) process. The CeO₂/SBA-15 catalyst was synthesized using a two-step impregnation method and thoroughly characterized to evaluate its structural, textural, and surface properties. The surface area (from 650 to 380 m² g⁻¹) and pore volume (from 0.820 to 0.620 cm³ g⁻¹) declined with the incorporation of cerium species, indicating successful metal incorporation within the mesoporous framework. EDX mapping revealed the uniform dispersion of the cerium species throughout the silica framework, while NH₃-TPD analysis confirmed the presence of both weak (<423 K) and strong (773–873 K) acid sites, which contributed to an enhanced catalytic activity. Among the prepared catalysts, the 2.5% CeO₂/SBA-15 catalyst demonstrated the highest catalytic efficiency, achieving maximum removal efficiencies of 95% for picoline and 92% for aniline under optimized reaction conditions. The reaction parameters were systematically improved, and Pearson correlation analysis, performed using Python revealed that the oxidant concentration, catalyst dose, and temperature were the most influential variables, each independently contributing on the degradation efficiency.