One-step synthesis of methanol and hydrogen from methane and water using non-thermal plasma and Cu-Mordenite catalyst

In this study, the copper-mordenite zeolite (Cu-MOR) and non-thermal plasma were used to produce methanol and hydrogen from methane and water at low temperature (120 °C) without CO 2 formation. Energy efficiency for methanol and hydrogen were 68.8 mmol·kJ −1 and 562.3 mmol·kJ −1 , respectively, and the selectivity of methanol in liquid products reached 86%. The reaction mechanism likely involves methane being excited to methyl (·CH 3 ) and hydrogen radicals (·H) under DBD plasma conditions, which can then adsorb on the catalyst surface at the Cu 2 -(μ-O) 2+ active sites, accompanied by water co-adsorption to facilitate formation and desorption of methanol. XPS analysis showed that with the prolongation of reaction time, Cu 2 -(μ-O) 2+ was reduced to Cu + and Cu(II) hydroxide, and the catalyst had carbon deposition , resulting in the decrease of catalytic activity . It is also worth noting that in an oxygen atmosphere, Cu 2 -(μ-O) 2+ regenerates rapidly and eliminates catalyst carbon deposits . Trace oxygen was introduced into the reactor, and the reaction was carried out for 30 h, and the catalytic activity did not decrease.