Patent GB-816610-A (GB)
Title: Improvements in or relating to process for the production of sulphonated alkylated aromatic hydrocarbons
IPC: C07C309/31
Filed: 1956-06-06
Abstract: Oil additive compositions containing sulphonated monoalkaryl and dialkaryl hydrocarbons substantially free of sulphur dioxide and sulphuric acid are produced by a process which comprises (a) the sulphonation of a mixture of alkaryl hydrocarbons consisting of 25 to 90 per cent by weight of monoalkaryl hydrocarbons and 75 to 10 per cent by weight of dialkaryl hydrocarbons with oleum wherein the parts (X) by weight of oleum per part by weight of said mixture of hydrocarbons employed are expressed by the equation X = (12.6 y-0.53) \sB 0.05 wherein y = weight per cent of the monoalkaryl hydrocarbons in said hydrocarbon mixture; (b) quenching the reaction mixture with 0.5 to 2.0 parts by weight of unsulphonatable oil, i.e. a light petroleum oil as defined below, per part by weight of said mixture of monoalkaryl and dialkaryl hydrocarbons and 0.05 to 0.2 parts by weight of water per part by weight of oleum used in (a) allowing the quenched reaction mixture to separate into two liquid phases, an upper phase comprising the unsulphonatable oil having dissolved therein the sulphonated monoalkaryl and dialkaryl hydrocarbons and a lower phase comprising water and spent acid; (d) separating the two phases; (e) diluting the recovered upper phase with a volatile aromatic hydrocarbon boiling up to about 140 DEG  C. and below the temperature of decomposition of the sulphonic acid wherein the weight of the aromatic hydrocarbon diluent is equal to 1.25 to 10 times that of the mixture of the monoalkaryl and di-alkaryl hydrocarbons; (f) allowing the diluted sulphonated hydrocarbons to separate into two liquid phases, an upper phase comprising said aromatic hydrocarbon diluent having dissolved therein said sulphonated monoalkaryl and dialkaryl hydrocarbons and unsulphonatable oil and a lower phase comprising spent acid and sludge; (g) separating the two phases and then (h) removing the volatile aromatic hydrocarbon contained in said upper phase so as to recover therefrom the sulphonated mono- and di-alkaryl hydrocarbons dissolved in said unsulphonatable oil.  The sulphonates may be employed as oil additives in the form of alkaline earth metal salts.  Unsulphonatable oils employed in the process are light petroleum oils which have been refined by treatment with sulphuric acid or other chemical process or by solvent extraction, e.g. with furfural, to remove aromatic and unsaturated hydrocarbons. Specific examples of such oils are white and pale oils.  Examples relate to the preparation of additives using as alkaryl hydrocarbon starting materials, fractions from the products obtained by alkylating benzene with propene (see Group IV (b)), pale and white oils as unsulphonatable oils and benzene as aromatic hydrocarbon diluent.ALSO:A process for the production of sulphonated monoalkaryl and di-alkaryl hydrocarbons free of sulphur dioxide and sulphuric acid comprises (a) the sulphonation of a mixture of alkaryl hydrocarbons consisting of 25 to 90 per cent by weight of monoalkaryl hydrocarbons and 75 to 10 per cent by weight of dialkaryl hydrocarbons with oleum wherein the parts (X) by weight of oleum per part by weight of said mixture of hydrocarbons employed are expressed by the equation X=(12.6y-0.53)\sB0.05 wherein y=weight per cent of the monoalkaryl hydrocarbons in said hydrocarbon mixture, (b) quenching the reaction mixture with 0.5 to 2.0. parts by weight of unsulphonatable oil, i.e a light petroleum oil, per part by weight of said mixture of mono-alkaryl and dialkaryl hydrocarbons and 0.05 to 0.2 parts by weight of water per part by weight of oleum used in (a), (c) allowing the quenched reaction mixture to separate into two liquid phases, an upper phase comprising the unsulphonatable oil having dissolved therein the sulphonated monoalkyl and dialkaryl hydrocarbons and a lower phase comprising water and spent acid, (d) separating the two phases, (e) diluting the recovered upper phase with a volatile aromatic hydrocarbon boiling up to about 140 DEG  C. such as benzene, toluene or xylene and below the temperature of decomposition of the sulphonic acid wherein the weight of the hydrocarbon diluent is equal to 1.25 to 10 times that of the mixture of monoalkaryl and dialkaryl hydrocarbons, (f) allowing the diluted sulphonated hydrocarbons to separate into two liquid phases, an upper phase comprising said aromatic hydrocarbon diluent having dissolved therein said sulphonated monoalkaryl and dialkaryl hydrocarbons and unsulphonatable oil and a lower phase comprising spent acid and sludge, (g) separating the two phases and then (h) removing the volatile aromatic hydrocarbon contained in said upper phase so as to recover therefrom the sulphonated mono- and di-alkylaryl hydrocarbons dissolved in said unsulphonatable oil.  In particular 0.9 to 1.1 parts by weight of unsulphonatable oil per part of said mixture of monoalkaryl and dialkaryl hydrocarbons and 0.09 to 0.125 parts by weight of water per part of oleum are employed in step (b).  Suitable light petroleum oils for use in step (b) are those which have been refined by a solvent or chemical process such as treatment with concentrated sulphuric acid to remove unsaturated and aromatic constituents, e.g. white oil or liquefied petrolatum or pale oil, i.e. a petroleum distillate lubricating oil which has been extracted with furfural or other solvent to remove aromatic and unsaturated hydrocarbons and dewaxed.  The aromatic hydrocarbon solution of sulphonic acid may be degassed by blowing with air or other inert gas.  Examples relate to the sulphonation of mixtures of mono- and di-alkaryl hydrocarbons, obtained by fractionating the product obtained by alkylating benzene with propene tetramer in the presence of aluminium chloride, with 10 and 20 per cent oleums in various proportions, white and pale oils being employed as unsulphonatable oils and benzene as aromatic hydrocarbon.  The products including the alkaline earth metal salts are employed as oil additives.