Pure H2 production by methane oxy-reforming over Rh-Mg-Al hydrotalcite-derived catalysts coupled with a Pd membrane

Abstract

Rh-Mg-Al hydrotalcites were synthesized by coprecipitation, then calcined and reduced to obtain catalysts active in the oxy-reforming of methane. In particular, it was shown that an increased activity can be obtained by reducing the Mg/Al ratio or increasing the Rh amount. In addition, the influence of pellet dimension and catalyst amount at same contact time was demonstrated to be negligible thanks to the characteristics of oxy-reforming which allows to work at low contact times without a sharp temperature rise. Moreover, a newly developed thermal treatment of the synthesized hydrotalcite was able to provide an active catalyst with an increased amount of reduced Rh over its surface, which provided very good performances. Finally, a hydrogen-selective Pd-membrane was integrated after the oxy-reforming and was able to separate H2 from the outlet mixture providing pure hydrogen in different conditions with high recoveries.