PROCESS FOR THE PRODUCTION OF FATTY ACID ALKYL ESTERS

Abstract: Fatty acid alkyl esters are produced by catalytic transesterification of a vegetable oil. In the presence of an alcohol having not more than two carbon atoms (e.g. methanol) and a catalyst taken from the alkaline earth metal calcium, (Ca), or compounds thereof transesterification of the vegetable oil is obtained at normal atmospheric pressure and a normal room temperature below 50 DEG C. The result of this reaction gives two separate phases: an ester phase containing the fatty acid alkyl esters and alcohol, and a glycerol phase comprising glycerol, alcohol and the catalyst.

Description: PROCESS FOR--THE PRODUCTION OF FATTY ACID ALKYL ESTERS DESCRIPTION The pre-esterification process is shown in a block diagram in accordance with the figure: 1. Alcohol 2. Catalyst 3. Vegetable oil 4. Reaction vessel with mechanical stirring 5. Residual product, glycerol, alcohol and catalyst. 6. The pre-esterification product A process for the production of simple fatty acid esters through catalytic transesterification of vegetable oil in the presence of a primary alcohol having a maximum of two carbon atoms. The process comprises: A. The alcohol (1), which in most of the tests started has been methanol, the quantity of which corresponded to a 10-20% stoichiometric excess, and a catalyst (2) are mixed in the reaction vessel (4) at normal atmospheric pressure and normal room temperature. The catalyst (2) is taken from the alkaline earth metals and compounds thereof. In the majority of tests started the catalyst (2) has been calcium, Ca. B. The vegetable oil (3), which in all tests has been rapeseed oil, is added to the reaction vessel (4) . The reaction starts on the condition that normal pressure and normal room temperature (15-20°C) apply. Reaction time increases at lower temperatures. When the reaction is complete, 80-98% of the bound glycerol has been released. The large variation in the glycerol obtained depends on how the stirring is carried out in the reaction vessel (4). The smaller quantity is obtained when the mixture remains unstirred. Two separate product phases can be identified in connection with the reaction in the reaction vessel (4), namely: a) The upper ester phase containing: 85 - 97 % fatty acid alkyl esters 3 - 15 % alcohol 0 - 2 % glycerol b) The lower glycerol phase containing 80 - 97 % glycerol 3 - 20 % alcohol ...0.02 % catalyst C. The b) phase, in a known manner, can easily be separated from the a) phase and collected in 5), while the a) phase is transferred to (6). D. The b) phase can be returned, either in untreated condition or via distillation, in a known manner, to the reaction vessel (4) for a new start of the process. In this way some of the alcohol and the catalyst are reused in the process. The process can be carried out batchwise or continuously. Example 1 A mixture of 500 ml (393 g) methanol with 4 g calcium is placed in a vessel at 22°C and normal air pressure. 3300 ml (3,03 kg) rapeseed oil is added to the vessel, and the entire mixture is stirred thoroughly at 22°C and normal air pressure. When the reaction is complete, the mixture can be separated into two phases. The upper phase contains 3,275 ml (2,880 g) methyl esters and 215 ml (170 g) methanol; while the lower phase contains 255 ml (300 g) glycerol and 89 ml (70 g) methanol. Samples have been taken from this process. Example 2 A mixture of 1.6 1 (1.26 kg) methanol and 8 g calcium is placed in a vessel with a mechanical stirrer. This example uses a substantially smaller amount of catalyst than the earlier example. 8.70 1 (7.96 kg) rapeseed oil is added to the vessel and the entire mixture is stirred thoroughl . Room temperature in this process varies slightly (16-20°C), while air pressure is normal. When the reaction is complete, the mixture can be separated into two phases. The upper ester phase produces 8.93 1 (7.83 kg) methyl esters and 0.63 1 (0.50 kg) methanol, while the lower phase produces 0.67 1 (0.80 kg) glycerol and 0.115 1 (0.090 kg) methanol.

Claims: CLAIMS 1. The process for production of fatty acid alkyl esters through catalytic transesterification of vegetable oil in the presence of a primary alcohol having a maximum of two carbon atoms. A. An alcohol having not more than two carbon atoms is mixed thoroughly with the catalyst in a reaction vessel at normal air pressure and normal room temperature. B. The vegetable oil is added to the reaction vessel and the mixture stirred well at normal air pressure and normal room temperature. C. The reaction (transesterification) takes place at normal air pressure and normal room temperature, and results in two phases which can be separated. An upper fatty acid ester phase, and a lower glycerol phase. D. The lower glycerol phase can be reused in the process either in untreated condition or via fractionation. 2. The catalyst mentioned in patent requirement 1 above refers to the alkaline earth metal calcium and compounds thereof. 3. The room temperature mentioned in patent requirement 1 above refers to a room temperature not exceeding 50°C.

Inventors: LINDQUIST CARL-JOHAN, LINDQUIST, CARL-JOHAN
Applicants: LINDQUIST CARL JOHAN, LINDQUIST, CARL-JOHAN
Application year: 1991
Main classification: C11C3
IPC codes: C07C67