Thermocatalytic Plasma-Assisted Dry Reforming of Methane Over Heterogeneous Ni/Al₂O₃ Catalyst.

A very promising area of plasma catalysis is the dry reforming of methane, whose symbiotic use of CH₄ and CO₂ mitigates the environmental impact of both greenhouse gases by transforming them into valuable syngas which can be used to produce petrochemicals. Because of the high carbon content in the feedstocks and harsh industrial reaction conditions, the dry reforming of methane is prone to coke formation, making the catalyst deactivation a severe problem for larger-scale industrial applications.

A study was conducted on the effect of key reaction parameters such as catalyst bed temperature, gas space velocity, plasma supply voltage, CH₄/CO₂ conversion, and selectivity of H₂ and CO. Each experiment was carried out in two distinct regimes using the same charge of the catalyst with and without the presence of plasma to determine the degree of catalyst deactivation from run to run, ending with a near-complete deactivation of the catalyst eventually recorded for the first stage and rapid recovery in the plasma stage.

While there are several possible explanations for the unexpected in-situ reactivation of the catalyst, the finding justifies further studies using already deactivated Ni/Al2O3 catalyst to determine the most efficient plasma-assisted reactivation protocol.