Cobalt based emission control catalysts with high resistance towards halide poisoning

Halide poisoning is a common problem in industrial exhaust control. In this study new catalysts have been searched, which effectively oxidize hydrocarbons in the presence of methyl bromide as halide containing pollutant. The search focused on low cost mixed metal oxides based on Ce, Co, Cr and Ni. Noble metals, Cu and Mn were neglected. High throughput technologies have been applied to accelerate the development process. Screening was based on emissivity corrected IR-thermography. Potential hits were validated using conventional gas phase flow catalysis. The tested catalysts were arranged in four ternary metal oxide composition spreads: Ce–Co–Cr, Ce–Co–Ni, Ce–Cr–Ni and Co–Cr–Ni. Out of the screening, Co–Ni mixed oxides had high CO conversion rates in the presence of methyl bromide. Further these catalysts were optimized by catalyst doping and composition variation. In a 50 h long term experiment the CO oxidation in the presence of methyl bromide was checked for our best catalyst Ce5Co90Ni5Ox. Additionally, the effect of various metal oxide additives on catalytic performance and BET surface is described.

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► High throughput technology composed of automated library preparation, emissivity corrected IR-thermography for screening.
► Conventional gas phase catalysis with GC-analysis for validation of potential hits.
► From over 250 materials studied, three catalysts emerged as best and most promising: Ce20Co40Cr40Ox, Co30Cr10Ni60Ox and Ce5Ni5Co90Ox.
► Materials of interest characterized by BET, XRD and XRF.
► Effect of various oxides or dopands on the catalytic performance.