Acetic acid synthesis from methane by non-synthesis gas process

Acetic acid was synthesized from a two-step process. In the first step, methane reacted with the water solution of HBr and oxygen to form CO and CH3Br over RuCl3/SiO2 catalyst, and in the second step, CH3Br reacted with CO and water to synthesize acetic acid over RhCl3 catalyst.