Synthesis characterization and Catalytic activity studies of Calcium boro phosphates supported Cu ni oxide catalyst for oxidation of Carbon monoxide and hydrocarbons

Abstract

Vehicular exhaust is the major contributor of carbon monoxide and newlineunburned hydrocarbon in the atmosphere, resulting in the reduced air quality. newlineThe effective conversion of these pollutants is achieved, using precious metals newlinesuch as Pd/Pt/Rh as catalyst, in the catalytic converter. These precious metals newlineare rarely available and expensive. Hence, using these metals is not feasible to newlinecater the ever increasing automobile population. Therefore, research on the newlinenon-noble metal/metal oxides has attracted the attention of the researchers newlineworldwide. Literature reveals, the non-noble metal/metal oxide supported on newlineconventional supports such as SiO2, CeO2, and ZrO2 as catalyst, for the newlineoxidation of CO and hydrocarbons. However, a reduction in the catalytic newlineactivity has been reported at higher temperature due to the catalyst newlinedeactivation. The present research work aims at achieving higher conversion newlineof CO and hydrocarbons, without involving any precious metal/rare earth newlineoxides as well as enhancing the catalyst stability even at higher temperature. newlineThe efficiency of the non-noble metal oxide based catalyst prepared, newlineemploying the non conventional support viz., calcium phosphate - newlineborophosphate in controlling the CO and unburned hydrocarbons emissions newlinefrom the engine exhaust was investigated. Initially, the catalyst supports newlineconsisting of Ca:P in the molar ratio of 1:0.9 with borate content varied newlinebetween 0.1-0.75M were prepared and sintered between 550°C 850°C. newlineBased on the XRD studies, the support sintered to a temperature of 750°C was newlinefound to be crystalline and accordingly optimized. Secondly, catalysts were newlineprepared by individually depositing CuO, NiO and mixed oxide of copper and newlinenickel on the calcium phosphate - borophosphate support (with varying borate newlinecontent) and the prepared catalysts were characterized using physicochemical