Process for hydrogenating a carboxylic acid or derivative thereof by feeding a carboxylic acid or derivative thereof and hydrogen to a reactor, maintaining conditions therein such that hydrogen reacts with the carboxylic acid and/or derivative thereof to form a product stream including one or more hydrocarbons and one or more oxides of carbon and feeding the product stream to a flash separator. A vapor fraction including the one or more oxides of carbon is separated from a liquid fraction having the one or more hydrocarbons. The concentration of carbon oxides in the flash separator is at or below a predetermined value.