Pb-substituted hydroxyapatites (Ca(10-x)Pbx(PO4)6(OH)2, x=0-10) prepared by coprecipitation method were studied as catalysts for oxidative coupling of methane using gas flow reactor in the temperature range of 675 to 800°C. They showed much higher activity for the production of C2 compounds than those of unsubstituted hydroxyapatites. Especially, Ca9.5Pb0.5(PO4)6(OH)2 showed the highest activity among them, which revealed maximum C2 yield of about 22%. As compared to the catalysts prepared by ion-exchange method, these catalysts had much higher activity and better thermal stability. Such high activity and stability of the catalysts could be confirmed by XPS, XRD, ICP, etc. to be resulted from the optimum amount of Pb substitution, uniformity of structure, and the maintenance of their own structure during the reaction.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry
- Surfaces, Coatings and Films
- Materials Chemistry