GB705408A - Improvements relating to synthetic detergents - Google Patents

Abstract

In the process for producing a synthetic detergent by sulphating mono-esters of polyhydric alcohols and fatty acids having 8 to 26 carbon atoms, or by sulphating a mixture of polyhydric alcohol and fatty material in the approximate proportions to give such a monoester, followed by neutralization, an alkylated aromatic compound having 8 to 26 alkyl carbon atoms is added to the reaction mixture at any stage prior to the neutralization. Preferably, a mixture of the alkylated aromatic compound and a polyhydric alcohol is first sulphonated and then the fatty material is introduced. Alternatively, the alkylated aromatic compound is first sulphonated with excess sulphonating reagent, and then a mixture of polyhydric alcohol and fatty material is added, or the polyhydric alcohol may first be sulphonated and then a mixture of the fatty material and alkylated aromatic compound is added. The polyhydric alcohol is preferably glycerol but ethylene glycol, diethylene glycol, propylene glycol or erythritol may be used. The fatty material preferably has a fatty acid content with 16 to 20 carbon atoms, and it may be in the form of free fatty acids or natural fats and fatty oils of vegetable, animal or marine origin. Suitable fatty materials include hydrogenated tallow, hydrogenated fish oil, hydrogenated whale blubber oil, fatty waxes such as spermaceti, or a mixture of hydrogenated fish oil and coconut oil. The alkylated aromatic compound may be derived from benzene, toluene, phenol or naphthalene and the alkyl substituent preferably has 12 to 14 carbon atoms. The sulphonating agent is preferably oleum containing 20 per cent. free SO3, but other agents such as chlorosulphonic acid and sulphur trioxide may be used. Other sulphonatable material which may be added to the reaction mixture includes fatty alcohols such as lauric and cetyl alcohols and mixtures of alcohols obtained from fatty oils; fatty amides and fatty alkanolamides. The sulphonated product is preferably neutralized with an alkaline sodium compound, such as a 30 per cent. aqueous solution of caustic soda, to a pH between 5.0 and 6.5. Builders may be added to the neutralized product and the mixture spray-dried to give a detergent composition (see Group III).ALSO:In the process for producing a synthetic detergent by sulphating mono-esters of polyhydric alcohols and fatty acids having 8 to 26 carbon atoms, or by sulphating a mixture of polyhydric alcohol and fatty material in the approximate proportions to give such a monoester, followed by neutralization, an alkylated aromatic compound having 8 to 26 alkyl carbon atoms is added to the reaction mixture at any stage prior to the neutralization. Preferably a mixture of the alkylated aromatic compound and a polyhydric alcohol is first sulphonated and then the fatty material is introduced. Alternatively, the alkylated aromatic compound is first sulphonated with excess sulphonating reagent, and then a mixture of polyhydric alcohol and fatty material is added, or the polyhydric alcohol may first be sulphonated and then a mixture of the fatty material and alkylated aromatic compound is added. The polyhydric alcohol is preferably glycerol but ethylene glycol, diethylene glycol, propylene glycol or erythritol may be used. The fatty material preferably has a fatty acid content with 16 to 20 carbon atoms, and it may be in the form of free fatty acids or natural fats and fatty oils of vegetable, animal or marine origin. Suitable fatty materials include hydrogenated tallow, hydrogenated fish oil, hydrogenated whale blubber oil, fatty waxes such as spermaceti, or a mixture of hydrogenated fish oil and coconut oil. The alkylated aromatic compound may be derived from benzene, toluene, phenol, or naphthalene and the alkyl substituent preferably has 12 to 14 carbon atoms. The sulphonating agent is preferably oleum containing 20 per cent. free SO3, but other agents such as chlorosulphonic acid and sulphur trioxide may be used. Other sulphonatable material which may be added to the reaction mixture includes fatty alcohols such as lauric and cetyl alcohols and mixtures of alcohols obtained from fatty oils; fatty amides and fatty alkanolamides. The sulphonated product is preferably neutralized with an alkaline sodium compound, such as a 30 per cent. aqueous solution of caustic soda, to a pH between 5.0 and 6.5. Builders may be added to the neutralized product and the mixture spray dried. Suitable builders include alkali metal phosphates, pyrophosphates, polyphosphates, silicates, borates and carbonates, and carboxymethyl cellulose, fatty alcohols, fatty acid amides, and fatty alkylamides.