An active copper-gold nanocatalyst for the direct partial oxidation of methane at low temperature

ZSM-5 supported copper-gold nanocatalyst (CuAu/ZSM-5) was prepared and investigated in the direct partial oxidation of methane to methanol. The reaction of methane with air was performed at the low temperature range of 333-423 K. Small-sized metal nanoparticles around 6.5 nm were well dispersed on the surface of ZSM-5. The presence of gold in CuAu/ZSM-5 not only affected chemical state of copper bus also benefited the promotion of catalytic activity. In the methane oxidation conducted at 423 K and 2.0 MPa over the CuAu/ZSM-5 catalyst, high yield of methanol reached 48.3% with high selectivity up to 100% to methanol. The CuAu/ZSM-5 catalyst had good recycling performance without the decrease of catalytic activity during four times reuses at least. [Received: December 10, 2014; Accepted: June 21, 2015]