Patent GB-603225-A (GB)
Title: Improvements in or relating to petroleum hydrocarbon products and the manufacture ofaddition agents therefor
IPC: C10M141/10
Filed: 1944-09-26
Abstract: Oxidation of petroleum hydrocarbons is inhibited by incorporating therein a metal salt of a thio-, seleno- or telluro-acid of phosphorus having at least one substituent comprising an alkylated aromatic sulphide, selenide or telluride group.  The antioxidants may be incorporated in such petroleum hydrocarbon compositions as crank-case lubricants, extreme pressure lubricants, engine flushing oils, general machinery oils, process oils such as cutting oils, rust preventive compositions, greases, motor fuels, particularly those containing tetraethyl lead or other anti-knock agents, Diesel fuels and kerosene.  The alkylated aromatic sulphide, selenide or telluride group of the antioxidant may contain aromatic nuclei other than benzene nuclei and various substituent atoms or groups may be attached to the aromatic nuclei such as alkyl, aryl, carboxyl, hydroxyl, alkoxy, sulphhydryl, nitro, esterified carboxyl, keto, amino, aldehydo, chlormethyl, aminomethyl, alkyl thiomethyl, alkyl xanthomethyl or methyl substituted sulphhydryl groups or halogen atoms.  Where the antioxidant is derived from a phenol sulphide or thiophenol sulphide, only one of the hydroxyl or sulphhydryl groups of this sulphide may be esterified with the radicle of the acid of phosphorus, remaining hydroxyl or sulphhydryl groups being either unsubstituted or substituted with a metal or with an ester, ether, aryl or similar group. Particularly suitable antioxidants are metal salts of thiophosphorous and thiophosphoric acids which contain at least one alkylated aromatic sulphide substituent, and up to four sulphur atoms may connect the two aromatic nuclei in the alkylated aromatic sulphide substituent.  If the antioxidant is to be used as an additive for petroleum lubricating oils, the reactions involved in its preparation may be carried out in a lubricating oil medium with the presence, if desired, of a higher alcohol such as stearyl alcohol, and the alcohol may be retained in the final lubricating oil composition.  Other additional materials which may be added to the petroleum hydrocarbon composition are detergents, dyes, pour point depressors, heat-thickened fatty oils, sulphurised fatty oils, organo-metallic compounds, metallic or other soaps, sludge dispersers, antioxidants, thickeners, viscosity index improvers, oiliness agents, resins, rubber, olefin polymers, voltolized fats, voltolized mineral oils, voltolized waxes, colloidal solids such as graphite or zinc oxide, solvents and assisting agents, such as esters, ketones, alcohols, aldehydes and halogenated or nitrated compounds.  Alcohols which may be employed as assisting agents include octyl, lauryl, cetyl, stearyl, heptadecyl or oleyl alcohol, naphthenic alcohols, phenyl octyl alcohol, octadecyl benzyl alcohol, alcohols from woolfat or sperm oil, or alcohols prepared by the oxidation of petroleum hydrocarbons such as paraffin wax or petroleum.  Materials rich in alcohols, such as woolfat or sperm oil, may be added instead of the alcohols themselves.  Detergents which may be used are metal soaps, metal petroleum sulphonates, metal phenates, metal alcoholates, metal alkyl phenol sulphides, metal organophosphates, thiophosphates, phosphites or thiophosphites, metal salicylates, metal xanthates or thioxanthates, metal phenol sulphonates, metal thiocarbamates, reaction products of metal alkyl phenates and sulphur, and reaction products of metal alkyl phenates and phosphorus sulphides.  Specific detergents mentioned are barium tert. octyl phenol sulphide, calcium tert. amyl phenol sulphide, nickel oleate, barium octadecylate, calcium phenyl stearate, zinc diisopropyl salicylate, aluminium or tin naphthenate, calcium cetyl phosphate, barium di-tert. amyl phenol sulphide, calcium petroleum sulphonate, zinc methyl cyclohexyl thiophosphate, calcium dichlorostearate, aluminium-calcium mixed soap of fatty acids from the oxidation of petroleum fractions and barium mahogany sulphonates. In the examples, mineral lubricating oil compositions containing (a) the zinc salt of the thiophosphate ester of tert, octyl phenol sulphide with or without stearyl alcohol, (b) barium salt of the thiophosphate ester of tert. octyl phenol sulphide, (c) barium salt of p-tert, octyl phenol sulphide thiophosphite and calcium petroleum sulphonate, (d) zinc salt of p-tert. octyl phenol sulphide thiophosphate, barium di-(tert. amyl) phenol sulphide and mixed calcium-sodium petroleum sulphonates, (e) calcium p-lauryl phenol sulphide thiophosphate and barium mahogany sulphonates, (f) magnesium diamyl phenol sulphide thiophosphite and calcium p-isohexadecyl phenol sulphide, (g) zinc p-tert. octyl phenol sulphide thiophosphate, calcium mahogany sulphonate and barium salt of paraffin wax alkylated phenol sulphide and disulphide, (h) zinc p-tert. octyl phenol disulphide thiophosphate, calcium mahogany sulphonate and magnesium p-isohexadecyl phenate, (1) zinc p-isohexadecyl phenol sulphide thiophosphate, basic calcium mahogany sulphonate and calcium octadecylate, (j) barium p-tert. octyl phenol sulphide thiophosphate, calcium mahogany sulphonate and sulphurised barium tert. octyl phenate and (k) zinc p-tert. octyl phenol sulphide thiophosphate, stearyl alcohol, mixed sodium-calcium petroleum sulphonates and sulphurised barium tert. octyl phenate.  The antioxidants may be salts of calcium, barium, strontium, magnesium, zinc, tin, nickel or aluminium and preferred antioxidants are obtained by reacting together an alkyl phenol sulphide, a sulphide of phosphorus and a metallic oxide or hydroxide.  Sulphides of phosphorus which may be employed include P2S5, P2S3, P4S3 and P4S7 as well as mixtures of these with sulphur and/or phosphorus.  In examples, (1) the zinc salt of the thiophosphate ester of tert. octyl phenol sulphide is prepared by reacting together p-tert. octyl phenol sulphide, zinc oxide and P2S5 in a mineral lubricating oil medium and (2) the thiophosphoric acid ester of tert. octyl phenol sulphide is prepared by reacting p-tert. octyl phenol sulphide with P2S5 and is then converted to its salt by neutralization with barium hydroxide or zinc oxide. Specifications 463,763, 498,046, 498,315, 586,512, 586,841, 590,885 and 593,738 are referred to.ALSO:Metal salts of thio-, seleno- or telluro-acids of phosphorus having at least one substituent comprising an alkylated aromatic sulphide, selenide or telluride group are employed as antioxidants in petroleum hydrocarbon products.  The alkylated aromatic sulphide, selenide or telluride group of the antioxidant may contain aromatic nuclei other than benzene nuclei and various substituent atoms or groups may be attached to the aromatic nuclei such as alkyl, aryl, carboxyl, hydroxyl, alkoxy, sulphhydryl, nitro, esterified carboxyl, keto, amino, aldehydo, chlormethyl, aminomethyl, alkyl thiomethyl, alkyl xanthomethyl or methyl substituted sulphhydryl groups or halogen atoms.  Where the antioxidant is derived from a phenol sulphide or thiophenol sulphide, only one of the hydroxyl or the sulphhydryl groups of this sulphide may be esterified with the radicle of the acid of phosphorus, remaining hydroxyl or sulphhydryl groups being either unsubstituted or substituted with a metal or with an ester, ether, aryl or similar group.  Particularly suitable antioxidants are metal salts of thiophosphorus and thiophosphoric acids which contain at least one alkylated aromatic sulphide substituent, and up to four sulphur atoms may connect the two aromatic nuclei in the alkylated aromatic sulphide substituent.  The antioxidants may be salts of calcium, barium, strontium, magnesium, zinc, tin, nickel or aluminium and preferred antioxidants are obtained by reacting together an alkyl phenol sulphide, a sulphide of phosphorus and a metallicoxide or hydroxide.  Sulphides of phosphorus which may be employed include P2S5, P2S3, P4S3 and P4S7 as well as mixtures of these with sulphur and/or phosphorus.  In an example, the thiophosphoric acid ester of tert.-octyl phenol sulphide is prepared by reacting p-tert-octyl phenol sulphide with P2S5 and is then converted to its salt by neutralization with barium hydroxide.  Specifications 463,763, [Group III], 498,046, 498,315, 586,512, 586,841, 590,885 and 593,738 are referred to.