Conversion of naphthalene as model compound of polyaromatics to mono-aromatic hydrocarbons under the mixed hydrogen and methane atmosphere

•Methane presence exerts a positive impact on naphthalene hydrocracking.•Methane might participate in the reaction, leading to preferred BTEX formation.•Catalyst with larger pore might benefit PAHs hydrocracking.•Catalyst surface acidity play a critical role on achieving desired PAHs hydrocracking.