Abstract
A series of LaBO3 (B=Cr, Co, Ni, Mn) and La0.9K0.1MnO3+δ perovskites have been prepared and tested as catalysts in the combustion of methyl ethyl ketone (MEK) at two concentration levels in air. Complete MEK conversion can be achieved for the most concentrated stream (1250ppmv, WHSV=425h−1) at temperatures between 270°C (manganite) and 345°C (chromite). Activity is governed by the nature of the cation in position B and related to reducibility, being comparable for manganite activity with that of the much more expensive Pt-supported catalysts. Doping with K of lanthanum manganite produces an increase in surface area, as well as the formation of non-stoichiometric oxygen and a greater proportion of Mn4+ on the surface. All these factors may have a role in increasing its activity for catalytic combustion. Catalytic results suggest a marked influence of MEK concentration on the combustion rate. MEK oxidation to CO2 goes through acetaldehyde as intermediate product; methyl vinyl ketone and diacetyl (2,3-butanedione) were also formed, albeit in very low amounts. Nevertheless, acetaldehyde yield is zero at complete conversion, so the combustion of MEK can be carried out over these perovskite systems with 100% selectivity for CO2.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
