Hydrolysis of methyl esters for production of fatty acids
AssigneeThe Procter & Gamble Company
InventorMichael S. Gibson
Life of this patent
Estimating the term…
Abstract
The present invention relates to an improved process for preparing fatty acids from alkyl, preferably methyl esters via acid hydrolysis by using ratios of water/ester/acid catalyst to form single phase reaction mixtures wherein the initial stoichiometric ratio of water to ester is at least about 1:1. These ratios are represented by the ternary phase diagram of FIG. 1 for a preferred C.sub.6 -C.sub.14 alkylbenzene sulfonic acid catalyst having mid-point attachment of the alkyl chain to the benzene ring.
Claims13
A process for the production of fatty acids comprising the following steps:
- (a) mixing specific ratios of fatty acid ester or mixtures thereof, with water and acid catalyst to form a single phase reaction mixture;
- and
- (b) heating the single phase reaction mixture to a temperature of from about 70.degree. C. to about 110.degree. C.;
- wherein the acid catalyst is substituted or non-substituted linear alkyl benzene sulfonic acid;
- wherein the initial stoichiometric ratio of water to ester is at least about 1:1;
- wherein the initial stoichiometric ratio of any residual amount of carboxylic acid, as a fatty acid ester impurity, to ester is less than 1:1 when said carboxylic acid contains less than 6 carbon atoms;
- wherein the ratios of acid catalyst/water/ester are the points in the area enclosed by the straight lines connecting points A (6.5/8.5/85) (catalyst/water/ester), B (90/0/10), C (96/2/2), D (1/97/2), E (21/49.5/29.5), F (11/27/62), G (8/24/68), and A (6.5/8.5/85), of FIG. 1, in order, excluding the shaded area, wherein the reaction mixture is essentially free of C.sub.2 -C.sub.5 carboxylic acid, and wherein the fatty acid ester has the formula:
- ##STR6## wherein R is a saturated or unsaturated aliphatic chain having from 5 to 20 carbon atoms, and R.sup.2 is a saturated or unsaturated aliphatic chain having from 1 to 4 carbon atoms.
A process for the production of fatty acids comprising the following steps:
- (a) mixing specific ratios of fatty acid ester or mixtures thereof, with water and acid catalyst to form a single phase reaction mixture;
- and
- (b) heating the single phase reaction mixture to a temperature of from about 70.degree. C. to about 110.degree. C.;
- wherein the reaction mixture is essentially free of C.sub.2 -C.sub.5 carboxylic acid, wherein the initial stoichiometric ratio of water to ester is at least about 1:1;
- wherein the initial stoichiometric ratio of any residual amount of carboxylic acid, as a fatty acid ester impurity, to ester is less than 1:1 when said carboxylic acid contains less than 6 carbon atoms;
- wherein the ratios of acid catalyst/water/ester are the points in the area enclosed by the straight lines connecting points A (6.5/8.5/85) (catalyst/water/ester), B (90/0/10), C (96/2/2), D (1/97/2), E (21/49.5/29.5), F (11/27/62), G (8/24/68), and A (6.5/8.5/85), of FIG. 1, in order, excluding the shaded area;
- the acid catalyst is a substituted or non-substituted linear alkyl benzene sulfonic acid of the formula:
- ##STR7## wherein R.sup.3 is an alkyl group having from 1 to 20 carbon atoms, and mixtures thereof, and wherein the fatty acid ester has the formula:
- ##STR8## wherein R is a saturated or unsaturated aliphatic chain having from 5 to 20 carbon atoms, and R.sub.2 is a saturated or unsaturated aliphatic chain having from 1 to 4 carbon atoms.
Dependencies are inferred from the claim text.