Applied Catalysis B: Environmental, Vol.204, 411-420, 2017
Benchmarking of manganese oxide materials with CO oxidation as catalysts for low temperature selective oxidation
CO oxidation behavior of different manganese oxide materials was studied as a model probe reaction to benchmark catalytic activities that could be useful for other aerobic oxidations. K-OMS-2, which showed intermediate activity [Ea=3.0 and 6.3 kcal/mol for K-OMS-2 (made in solvent free procedure or SF) and K-OMS-2 (made via hydrothermal route or REF) respectively], were chosen for metal dopant studies using microwave assisted hydrothermal synthesis. These were further characterized using X-ray diffraction (XRD), N-2 sorption, Raman spectroscopy, scanning electron microscopy (SEM), and carbon monoxide temperature programmed reduction (CO-TPR). Additional characterization was carried out for Ni-K-OMS-2 materials using atomic absorption spectroscopy (AAS) and thermogravimetric analysis mass spectroscopy (TGA-MS). Doping K-OMS-2 with Ni resulted in a large increase in oxygen mobility and re-adsorption, and the moderate activation energy for CO oxidation (13. kcal/mol) by Ni-K-OMS-2(SF) suggests that Ni-doped materials are good candidates for low temperature selective oxidation. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Carbon monoxide oxidation;Octahedral molecular sieve catalysts;Transition metal ion doped manganese oxide