L. Lietti et al., OXIDATIVE COUPLING OF METHANE OVER ALKALI-PROMOTED TI-LA OXIDE CATALYSTS - EFFECT OF BULK AND SURFACE-PROPERTIES ON CATALYTIC PERFORMANCE, Catalysis letters, 36(3-4), 1996, pp. 151-157
The reactivity of lanthanum titanate catalysts is investigated in the
oxidative coupling of methane (OCM) under lean-oxygen conditions. The
catalyst performances are influenced by the catalyst preparation metho
d and by the amounts of the alkali dopant. A transient method was also
used to study the mobility of lattice oxygen species under OCM reacti
on conditions. It is found that (i) in the absence of gas phase oxygen
the sample does not possess lattice oxygen species which participate
in the reaction; (ii) the alkali doping does not appreciably modify th
e mobility of lattice oxygen; and (iii) the role of the alkali promote
r in the reaction is that of modifying the surface acid/base and oxidi
zing properties.