Treatment of alcohol compositions
AssigneeBp P.L.C.
InventorMatthew Bough
Life of this patent
Estimating the term…
Abstract
Process for reducing the water and carboxylic acid content of an alcohol composition containing at least one C1-4 alcohol, water and at least one C1-4 carboxylic acid by (a) forming a vapor phase alcohol composition A and a liquid phase alcohol composition B, (b) separating a second vapor phase alcohol composition C and an aqueous phase D from the liquid phase alcohol composition B, the aqueous phase D containing the majority of the carboxylic acid that was present in the liquid phase alcohol composition B; (c) passing the vapor phase alcohol composition A to a drying unit, (d) passing the vapor phase alcohol composition C to a drying unit; and (e) recovering an alcohol composition from the drying units of steps (c) and (d). The recovered alcohol composition of step (e) has a reduced water and carboxylic acid content.
Claims15
A process for reducing the water and carboxylic acid content of an alcohol composition comprising at least one alcohol having from one to four carbon atoms, water and at least one carboxylic acid having from one to four carbon atoms, wherein said process comprises:
- (a) forming a vapour phase alcohol composition A and a liquid phase alcohol composition B from the alcohol composition;
- (b) separating a second vapour phase alcohol composition C and an aqueous phase D from the liquid phase alcohol composition B in a distillation column, wherein the aqueous phase D contains the majority of the carboxylic acid that was present in the liquid phase alcohol composition B;
- (c) passing the vapour phase alcohol composition A to a drying unit comprising a desiccant;
- (d) passing the vapour phase alcohol composition C to a drying unit comprising a desiccant;
- and
- (e) recovering an alcohol composition from the drying unit of step (c) and the drying unit of step (d);
- wherein the recovered alcohol composition of step (e) has a reduced water and carboxylic acid content.
A method of preparing a fuel alcohol composition from an alcohol composition comprising at least one alcohol having from one to four carbon atoms, water and at least one carboxylic acid having from one to four carbon atoms, wherein said method involves:
- (a) determining the concentration of water and carboxylic acid present in the alcohol composition;
- (b) if the alcohol composition comprises a concentration of water which is greater than the azeotropic concentration for the alcohol composition, passing the entire alcohol composition to a distillation column of step (c) as a liquid phase alcohol composition B;
- if the alcohol composition comprises a concentration of water which is equal to or lower than the azeotropic concentration for the alcohol composition, and the carboxylic acid concentration is equal to or lower than the maximum desired concentration of carboxylic acid in the fuel alcohol composition, vaporising the entire alcohol composition to form a vapour phase alcohol composition A;
- or
- if the alcohol composition comprises a concentration of water which is equal to or lower than the azeotropic concentration for the alcohol composition, and the carboxylic acid concentration is greater than the maximum desired concentration of carboxylic acid in the fuel alcohol composition, forming a vapour phase alcohol composition A and a liquid phase alcohol composition B from the alcohol composition;
- (c) separating a second vapour phase ethanol composition C and an aqueous phase D from the liquid phase ethanol composition B, if present, in a distillation column, wherein the aqueous phase D contains the majority of the carboxylic acid that was present in the liquid phase alcohol composition B;
- (d) passing the vapour phase alcohol composition A, if present, to a drying unit comprising a desiccant;
- (e) passing the vapour phase alcohol composition C, if present, to a drying unit comprising a desiccant;
- and
- (f) recovering a fuel alcohol composition from the drying unit of step (d), if present, and the drying unit of step (e), if present;
- wherein the recovered fuel alcohol composition has a reduced water content.
Dependencies are inferred from the claim text.