Patent GB-818368-A (GB)
Title: A process for the preparation of mixtures of surface-active agents and compositions containing such mixtures, and the resulting mixtures and compositions
IPC: C07C309/28
Filed: 1956-09-14
Abstract: A mixture of surface-active alkyl aryl sulphonates and secondary alkyl sulphates is prepared by a process wherein organic material which has remained unconverted during the sulphonation and/or sulphation of the respective alkylate and olefin starting materials is removed by extraction of the mixture of alkyl aryl sulphonates and alkyl sulphates obtained after separate or combined neutralization and desalting of the alkyl aryl sulphonic acids and alkyl sulphuric acids.  Neutralization is normally carried out with an alkali metal hydroxide or carbonate, for example caustic soda, or sodium carbonate.  A variety of solvents, for example gasoline, may be used for the extraction step.  Lower aliphatic alcohols, preferably lower secondary aliphatic alcohols, such as isopropanol, are suitable for use in the desalting step. The mixture of alkyl aryl sulphonic acids and alkyl sulphuric acids used in the process may be prepared by mixing alkyl aryl sulphonic acids and alkyl sulphuric acids prepared separately or by using the reaction mixture obtained after sulphonation of the alkylates with oleum as the sulphating agent for sulphation of the olefins.  A diluent such as one or more paraffins with 4 to 7 carbon atoms in the molecule, e.g. aromatic-free gasolines, may be present during sulphonation in an amount of 1/2 to 5 volumes per volume of compound to be sulphated.  Preferably the starting material used for the preparation of mixtures of alkyl aryl sulphonates and alkyl sulphates comprises: (1) alkyl aryl sulphonic acids obtained by sulphonating an alkylate prepared by alkylation of an aromatic hydrocarbon with C8/C9-C12\sB1 olefin mixture obtained by splitting a C8/C9-C18\t olefin mixture into a C/8C9-C12\sB1 fraction and a C13\sB-C18 fraction, together with (2) alkyl sulphates obtained by sulphation of the lastmentioned fraction. It is also preferred that the mixture subjected to extraction should contain the alkyl aryl sulphonates and alkyl sulphates in a ratio lying between 60/40 and 20/80 .  The process may be used to prepare the mixtures described in Specification 818,367.  The mixtures of alkyl aryl sulphonates and secondary alkyl sulphates may be used as such, or if desired, after dilution with water.  The mixtures may, however, also be worked up to form compositions, e.g. by adding other detergents, phosphates, silicates, carbonates, foam stabilizers, washing promoters or bleaching agents.  Specification 818,369 also is referred to.ALSO:A mixture of surface-active alkyl aryl sulphon ates and secondary alkyl sulphates is prepared by a process wherein organic material which has remained unconverted during the sulphonation and/or sulphation of the respective alkylate and olefin starting materials is removed by extraction of the mixture of alkyl aryl sulphonates and alkyl sulphates obtained after separate or combined neutralization and desalting of the alkyl aryl sulphonic acids and alkyl sulphuric acids.  Neutralization is normally carried out with an alkali hydroxide or carbonate, for example caustic soda, or sodium carbonate.  A variety of solvents, for example gasoline, may be used for the extraction step.  Lower aliphatic alcohols, preferably lower secondary aliphatic alcohols, such as isopropanol, are suitable for use in the desalting step. The mixture of alkyl aryl sulphonic acids and alkyl sulphuric acids used in the process may be prepared by mixing alkyl aryl sulphonic acids and alkyl sulphuric acids prepared separately or by using the reaction mixture obtained after sulphonation of the alkylates as the sulphating agent for sulphation of the olefins. It is advisable in the latter case to use oleum, e.g. containing 20 per cent by weight of free SO3, for sulphonation of the alkylates, starting with a mol. ratio of SO3 : alkylate of between 5 and 7 : 1.  A diluent such as one or more paraffins with 4 to 7 carbon atoms in the molecule, e.g. aromatic-free gasolines, may be present during sulphonation in an amount of 1/2 to 5 volumes per volume of compound to be sulphated. Preferably the starting material used for the preparation of mixtures of alkyl aryl sulphonates and alkyl sulphates comprises (1) alkyl aryl sulphonic acids obtained by sulphonating an alkylate prepared by alkylation of an aromatic hydrocarbon with a C8/C9-C12\sB1 olefin mixture obtained by splitting a C9/C8-C19 olefin mixture into a C8/C9-C12\sB1 fraction and a C13\sB-C18 fraction, together with (2) alkyl sulphates obtained by sulphation of the last-mentioned fraction. It is also preferred that the mixture subjected to extraction should contain the alkyl aryl sulphonates and alkyl sulphates in a ratio lying between 60/40 and 20/80 .  The process may be used to prepare the mixtures described in Specification 818,367. The mixtures of alkyl aryl sulphonates and secondary alkyl sulphates may be used as such, or if desired after dilution with water.  The mixtures may, however, also be worked up to form compositions, e.g. by adding other detergents, phosphates, silicates, carbonates, foam stabilizers, washing promoters or bleaching agents.  In examples: (1) benzene is alkylated with a C8-C13 olefin mixture in a ratio of 10 : 1 in the presence of HF at room temperature and 4 atmospheres and the alkylate is sulphonated at 55 DEG  C. with 20 per cent oleum after which the mixture is diluted with water to give a 65 to 75 per cent H2SO4 concentration; the resulting mixture is added in a proportion of 40/60 to a mixture of secondary alkyl sulphuric acids prepared by sulphation of a C8-C18 olefin mixture with 98 per cent sulphuric acid; the total mixture is neutralized, saponified, and then desalted with isopropyl alcohol and extracted with gasoline; (2) benzene is alkylated with a C8-C12 olefin fraction as in (1) and the mixture obtained is used for sulphation of C13-C18 olefins, the resulting mixture being neutralized and then worked up as in (1); (3) alkylbenzenes with 10-14 carbon atoms in the alkyl groups, are sulphonated with 25 per cent oleum in a mol. ratio of alkylate to SO3 of 1 : 5 at 55 DEG  C. for 30 minutes and the reaction mixture is used to sulphate C8-C18 olefins, with or without pentane as a diluent, with various ratios of reactants and at temperatures of 0 DEG , 5 DEG  and 10-15 DEG  C., the mixtures obtained being neutralized, desalted as in (1) and extracted with gasoline. Specification 818,369 also is referred to.