Minimizing carbon deposition in plasma-induced methane coupling with structured hydrogenation catalysts

The effect of temperature and hydrogen addition on undesired carbonaceous deposit formation during methane coupling was studied in DBD-plasma catalytic-wall reactors with Pd/Al2O3, using electrical power to drive the reaction. Experiments thin catalyst layers allowed comparison performance empty catalytic wall without significantly influencing plasma properties. product distribution varies strongly window between 25 200 °C. Minimal deposits is found at an optimal around 75 °C reactors. selectivity c.a. 10% only 9 mg loading instead 45% blank reactor, while decreasing conversion mildly. Co-feeding H2 reactor causes a similar decrease deposits, but this case also decreased significantly. Suppression due hydrogenation mainly acetylene ethylene. In co-feed decreases does not change distribution. can be regenerated H2-plasma room temperature, which produces more added-value hydrocarbons.