Sulfonating olefins with gaseous sulfur trioxide

摘要

Liquid light-duty and heavy-duty detergent compositions contain as the active ingredient a mixture of an n-alkene sulphonate and a gamma-hydroxy n-alkyl sulphonate, said mixture being prepared by hydrolysing and neutralizing the product obtained by sulphonating a C12- 20 olefin with SO3 under specified conditions (see Division C2). The cation of the neutralized sulphonates may be alkali metal (e.g. Na) or ammonium. Additives which may be present include polyphosphates, e.g. potassium tripolyphosphate and tetrapotassium pyrophosphate, sodium silicate, hydrotropes, e.g. sodium xylene sulphonate, higher fatty acid alkanolamides, aliphatic tertiary amine oxides, sodium nonyl phenyl ether sulphonate, and carboxy-methyl cellulose. Reference has been directed by the Comptroller to Specification 991,819.ALSO:A surface-active composition is prepared by (a) continuously introducing at a substantially uniform rate a gaseous mixture of from 0.1 to 10 parts by volume sulphur trioxide and correspondingly from 99.9 to 90 parts by volume of an inert carrier gas into a liquid charge of an essentially linear 12-20 carbon atom olefin maintained at a temperature not greater than 50 DEG C. until not in excess of 1.1 mole of sulphur trioxide is reacted per mole of olefin, (b) and (c) hydrolysing and neutralizing the resultant reaction product with a water-soluble base and (d) recovering as the surface-active composition the sulphonate content of the resulting mixture. Either acid, neutral or basic hydrolysis is applicable and is preferably carried out at a temperature greater than 70 DEG C. Suitable inert carrier gases are sulphur dioxide, nitrogen, air, hydrogen or argon. The olefins may be either terminally or internally unsaturated and especially suitable are those containing from 15-17 carbon atoms or mixtures of even-numbered carbon atom alpha-olefins which contain a substantial amount of 1-n-hexadecene and have an average molecular weight corresponding to that of said isomer. Linear unsymmetrical dialkyl olefins may also be used. The initial product formed from the reaction of sulphur trioxide with a straight-chain mono-olefin is a mixture of an unsaturated aliphatic sulphonic acid and an alkyl gamma-sultone. On hydrolysis the sultone content is converted to gamma hydroxy alkyl sulphonic acid and the surface-active composition consists therefore of a watersoluble salt of a mixture of gamma hydroxy alkyl and alkene sulphonic acids. The sultone content of the sulphonation product may be isolated by neutralizing the sulphonation product, extracting with a light hydrocarbon such as pentane, hexane or heptane and then distilling off the hydrocarbon. The surface-active composition may suitably be used in the preparation of heavy and light-duty detergent compositions (see Division C5). Reference has been directed by the Comptroller to Specification 991,819.