Patent GB-717347-A (GB)
Title: Improvements in or relating to process for preparing pour depressants
IPC: C10M127/06
Filed: 1952-03-21
Abstract: Aromatic hydrocarbons or their hydroxy derivatives are alkylated with olefins or haloalkanes in presence of a Friedel-Crafts' catalyst and a solvent consisting of a hydrocarbon oil having a viscosity at 210 DEG  F of 30-220, preferably 140-200, S.U.S., and boiling above 300 DEG  C.  The products are pour-point depressants.  The aromatic compound may be benzene, naphthalene, diphenyl, phenanthrene, anthracene, pyrene, chrysene, toluene, xylene, indene, methyl naphthalene, acenaphthene, fluorene, phenol, cresols, xylenols or naphthols.  The alkylation agent may be one or more haloalkanes which should include a major proportion of poly-halogenated molecules, preferably with a halogen atom on each terminal carbon atom.  Those having 8-30 carbon atoms in a straight chain are preferred, e.g. octyl, decyl, lauryl, and octadecyl halides or halogenated paraffin wax, petrolatum, naphtha, gas oil, kerosene or lubricating oil. Olefins having 8-30 carbon atoms, preferably in a straight chain, including synthesis or polymerization products, diolefins, and especially thermally cracked wax or petrolatum may be used.  The preferred agent is a chlorinated wax of 8-30 per cent chlorine and containing 20-30 carbon atoms in a straight chain.  The catalyst may be an aluminium halide or mixed halide, zinc chloride, boron fluoride or complexes with alkyl halides such as methyl chloride.  Reaction is effected at 75-300, preferably 100-175 DEG  F., for 2-8, preferably 4-6 hours.  About 0.3-5, preferably 1-3 mols. of alkylating agent per mol. of aromatic compound are used.  In an example, 150 S.U.S. bright stock and naphthalene are treated with AlCl3, and chlorowax added while temperature rises from 94-116 DEG  F.  A temperature of 125 DEG F. is then maintained for 4 hours, the product diluted with mineral oil, catalyst destroyed, and product recovered by steam distillation. Further examples illustrate variation in yield with reaction time and temperature, pour depressant and pour stability properties of the products, effect of varying the solvent ratio which should be 15-25, preferably 20-25, parts per 100 parts chlorowax, and the effect of varying viscosity of the solvent oil. The products are added to lubricating oils in amounts of 0.02-10, preferably 0.1-5, per cent or prepared as concentrates of 10-80 per cent.  Extreme pressure agents, V.I. improvers, inhibitors, detergents, de-emulsifiers and the like may be incorporated.ALSO:Pour point depressants for lubricating oils comprise the products of alkylating aromatic hydrocarbons or their hydroxy derivatives with olefins or halo-alkanes in presence of a Friedel-Crafts catalyst and a solvent consisting of a hydrocarbon oil having a viscosity at 210 DEG F, of 30-220, preferably 140-200 S.U.S., and boiling above 300 DEG C.  The aromatic compound may be benzene, naphthalene, diphenyl, phenanthrene, anthracene, pyrene, chrysene, toluene, xylene, indene, methyl naphthalene, acenaphthene, fluorene, phenols, cresols, xylenols or naphthols. The alkylation agent may be one or more halo-alkanes which should include a major proportion of poly-halogenated molecules, preferably with a halogen atom on each terminal carbon atom. Those having 8-30 carbon atoms in a straight chain are preferred, e.g. octyl, decyl, lauryl, and octadecyl halides or halogenated paraffin wax, petrolatum, naphtha gas oil, kerosene or lubricating oil, olefins having 8-30 carbon atoms, preferably in a straight chain including synthesis or polymerization products, diolefins and especially thermally cracked wax or petrolatum may be used. The preferred agent is a chlorinated waxx of 8-30 per cent. chlorine and containing 20-30 carbon atoms in a straight chain. In an example, a 150 S.U.S. bright-stock and naphthalene are treated with AlCl3 and chlorowax added while temperature rises from 94-116 DEG F.  A temperature of 125 DEG F. is then maintained for 4 hours, the product diluted with mineral oil, catalyst destroyed and product recovered by steam distillation. Further examples illustrate variation in yield with reaction time and temperature, pour depressant and pour stability properties of the products, effect of varying the solvent ratio which should be 15-25 preferably 20-25 parts per 100 parts chlorowax, and the effect of varying viscosity of the solvent oil.  The products are added to mineral lubricating oils in amounts of 0.02-10 preferably 0.1-5 per cent or prepared as concentrates of 10-80 per cent. Extreme pressure agents, V.I. improvers, inhibitors, detergents, de-emulsifiers and the like may be incorporated.