TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The promoter is chosen from ruthenium and osmium. The catalyst(s) employed in the hydrogenation unit is a copper-based catalyst, most preferably comprising copper and zinc. Preferred Condition: When copper-based catalyst is employed in the hydrogenation unit(s), the feed mixture introduced into the hydrogenation reactor(s) is always above its dew point temperature.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: A carbonaceous feedstock is introduced into a synthesis gas generation unit to produce synthesis gas. Synthesis gas is introduced into a methanol synthesis reactor to produce methanol. Methanol together with carbon monoxide is introduced into a carbonylation reactor to produce ethanoic acid. The process of producing ethanoic acid by carbonylation of methanol comprises contacting methanol with carbon monoxide in the liquid reaction composition containing ethanoic acid, an iridium catalyst, methyl iodide, water and a promoter in a carbonylation reactor. The ethanoate stream exiting the esterification reactor which also contains unreacted ethanoic acid and residual esterification catalyst is subjected to a purification process to remove ethanoic acid and esterification catalyst before introduction into the hydrogenation unit. The carbon monoxide fed to the carbonylation reactor and hydrogen fed to the hydrogenation unit emanates from the separation of the synthesis gas. Methyl ethanoate/methanol mixture is recovered from the exit stream of the hydrogenation unit and is recycled into the esterification unit. Ethyl ethanoate/ethanol mixture is recovered from the exit stream of the hydrogenation unit and is recycled into the esterification unit. Preferred Properties: The concentration of water in the liquid reaction composition of the carbonylation reactor is 0.1-15 weight%, more preferably 1-10 weight%, most preferably 1-6.5 weight%. The molar ratio of methanol and ethanol with respect to ethanoic acid introduced into the esterification reactor is 1.1-3, preferably 1.1-2. The content of water added to the hydrogenation reactor is 0.5-20 mol%, preferably 0.5-15 mol%, most preferably 1-5 mol% of the total liquid feed comprising ethanoate, alcohol and water entering into the hydrogenation reactor. The molar ratio of hydrogen with respect to methyl ethanoate and ethyl ethanoate introduced into the hydrogenation unit is more than 2:1 and less than 100:1, preferably more than 4:1 and less than 50:1, most preferably more than 5:1 and less than 15:1.