Resource utilization of waste deNOx catalyst for continuous-flow catalysis by supported metal reactors

Abstract

Resource utilization of waste deNOx catalysts has become a major demand. A new resource path for continuous-flow catalysis using the waste deNOx catalysts (V2O5-WO3/TiO2, CeO2-WO3/TiO2 and MnO2-CeO2/TiO2) as carriers was proposed. The waste deNOx catalysts supported NiO catalysts prepared by an in-situ preparation method were used to investigate continuous-flow nanocatalysis of p-nitrophenol reduction. The result showed that the MnO2-CeO2/TiO2 supported NiO (Ni/TMC) exhibited excellent catalytic performance in the catalytic reduction of p-nitrophenol (4-NP). The conversion of 4-NP (2.5 mM) reached nearly 100% at the injection speed of 1.5 mL·min−1. It maintained 100% conversion after 10 recycling time since waste deNOx catalysts could reduce aggregation for NiNPs. Furthermore, high oxygen vacancy, chemisorbed oxygen, and the strong interaction between Ni and waste deNOx catalyst resulted in a highly efficient, recoverable and cost-effective multifunctional reactor. All of these advantages present the opportunity to be implemented in the field of wastewater treatment and environmental toxicology.