Kinetic behaviour of three samples of samarium oxide (cubic (Sm-1 ), monoclinic (Sm-3) and mixed cubic-monoclinic (Sm 2) ) were studied in the oxidative coupling of methane using a gradientless flow circulation system. The specific rate of C2product formation differed by a factor of 6-8 for Sm-1 and Sm-3. The specific activity for CO formation did not depend upon the crystal structure of samari...

It has been found that it is possible to improve the activity and stability for the oxidative coupling of methane of a Li/MgO catalyst by the addition of small amounts of the oxides of various transition and rare earth metals. A number of these additives, e.g. SnOZ, TiOz, Dy,O, and Tb407, caused little or no difference in the selectivity to C, products achieved with the resultant catalyst while...

A series of zirconia doped Li/MgO catalysts with a fixed amount of zirconia and varying concentrations of lithium was used for the oxidative coupling of methane. It was found that an increase in lithium concentration resulted in a decrease in initial activity, while the selectivity was not affected. The life-time of Zr doped Li/MgO catalysts with a fixed concentration of ZrOz is a function of t...

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The oxygen-free conversion of methane on transition-metal catalysts could be an interesting alternative to the oxygen-containing conversion (OCM) due to its higher selectivity towards higher hydrocarbons (C2+). So far, the main obstacle has been the low conversion rate compared to the OCM process. This is mostly ascribed to the fact that oxygen-free CH4-conversion is accompanied by a quick depo...