| abstract |
A process for preparing formic acid by reaction of carbon dioxide ( 1 ) with hydrogen ( 2 ) in a hydrogenation reactor (I) in the presence ofn a catalyst comprising an element of group 8, 9 or 10 of the Periodic Table, a tertiary amine comprising at least 12 carbon atoms per molecule and a polar solvent comprising one or more monoalcohols selected from among methanol, ethanol, propanols and butanols and also water,n nto form formic acid/amine adducts as intermediates which are subsequently thermally dissociated, with work-up of the output ( 3 ) from the hydrogenation reactor (I) in a plurality of process steps, wheren na tertiary amine-comprising stream ( 13 ) from the work-up is used as selective solvent for the catalyst, is proposed. |