Abstract:
The present invention relates to a method for producing carboxylic acid esters, comprising the reaction of at least one primary mono alcohol or a mixture of a primary mono alcohol and at least one alcohol differing from this in the presence of a transition metal carbene complex catalyst (K), which has as the central atom (M) at least one transition metal atom of group 8, 9 or 10 of the periodic table (IUPAC) and at least one monodentate N-heterocyclic carbene ligand, in the presence of a base, characterized in that the catalyst (K) is produced by reaction of a transition metal compound (V), which has at least one transition metal atom of group 8, 9 or 10 of the periodic table (IUPAC), but no carbene ligand, with an imidazolium salt in the presence of the primary mono alcohol and the base, wherein the reaction is a bulk reaction.
Abstract:
The invention relates to a method for obtaining formic acid by the thermal separation of a flow containing formic acid and a tertiary amine (I), wherein a liquid flow which contains formic acid and a tertiary amine (I) in a molar ratio of 0.5 to 5 is produced by combining tertiary amine (I) and a source of formic acid, 10 to 100 wt % of the secondary components contained in said flow are separated, and formic acid is removed by distillation from the resulting liquid flow in a distillation device at a bottoms temperature of 100 to 300°C and a pressure of 30 to 3000 hPa abs, wherein the bottoms product from the distillation device is separated into two liquid phases and the upper liquid phase is returned to the source of formic acid and the lower liquid phase is returned for separation of the secondary components and/or to the distillation device.