Acetic acid was synthesized from methane by non-syngas process. In the process, methane was brominated with hydrogen bromide (40 wt.% HBr/H2O) and oxygen to give CH3Br and CO over a Ru/SiO2 catalyst. The as-generated CO and CH3Br reacted with water under the catalysis of RhCl3 to produce acetic acid, methanol, and methyl acetate. In the first step oxidative bromination reaction, 30.1% of methane single pass conversion with 72.4% of CH3Br selectivity and 25.5% of CO selectivity was attained. In the second step, almost 100% CH3Br conversion was reached. (C) 2004 Elsevier B.V. All rights reserved.