Patent GB-477923-A (GB)
Title: Manufacture of oily condensation products useful for imparting colour and fluorescence to lubricating oils
IPC: C07C2/86
Filed: 1936-07-17
Abstract: Products useful for imparting colour and fluorescence to lubricating oils are obtained by condensing an aromatic hydrocarbon, in the presence of a Friedel-Crafts catalyst, with a chlorinated higher aliphatic hydrocarbon (as defined below) containing not less than 35 per cent of chlorine, separating the lower of the two layers into which the mixture separates, removing the catalyst from the lower layer, and heating the residue of the lower layer until a homogeneous melt is obtained, a temperature of 300--400 DEG  C. being generally suitable for that purpose.  A higher aliphatic hydrocarbon is defined as an aliphatic hydrocarbon having a molecular weight above 200.  If the final product contains matter insoluble in lubricating oils, this may be eliminated by extracting the oil-soluble constituents from the product with a solvent such as benzene or toluene, the solvent being then distilled off from the extract; alternatively, the product may be extracted with a lubricating oil.  The aromatic hydrocarbon may be benzene, toluene or xylene, and may be taken in excess; alternatively, an inert solvent, e.g. petroleum ether, may be added, and in that case a solid aromatic hydrocarbon, e.g. naphthalene, may be used.  In an example, chlorinated paraffin wax containing 40 per cent of chlorine is mixed with benzene, and the mixture is treated slowly with anhydrous aluminium chloride; the mixture is then heated to 70--80 DEG  C., and afterwards allowed to separate into layers; the lower layer is warmed with dilute hydrochloric acid, to remove aluminium chloride, dried, heated to 300--400 DEG  C. and then extracted with benzene, which is finally distilled from the extract.ALSO:Products useful for imparting colour and fluorescence to lubricating oils are obtained by condensing an aromatic hydrocarbon, in the presence of a Friedel-Crafts catalyst, with a chlorinated higher aliphatic hydrocarbon (as defined below) containing not less than 35 per cent of chlorine, separating the lower of the two layers into which the mixture separates, removing the catalyst from the lower layer, and heating the residue of the lower layer until a homogeneous melt is obtained, a temperature of 300--400 DEG  C. being generally suitable for that purpose.  A higher aliphatic hydrocarbon is defined as an aliphatic hydrocarbon having a molecular weight above 200.  If the final product contains matter insoluble in lubricating oils, this may be eliminated by extracting the oil-soluble constituents from the product with a solvent such as benzene or toluene, the solvent being then distilled off from the extract; alternatively, the product may be extracted with a lubricating oil.  The aromatic hydrocarbon may be benzene, toluene or xylene, and may be taken in excess; alternatively, an inert solvent, e.g. petroleum ether, may be added, and in that case a solid aromatic hydrocarbon, e.g. naphthalene, may be used.  In an example, chlorinated paraffin wax containing 40 per cent of chlorine is mixed with benzene, and the mixture is treated slowly with anhydrous aluminium chloride; the mixture is then heated to 70--80 DEG  C., and afterwards allowed to separate into layers; the lower layer is warmed with dilute hydrochloric acid, to remove aluminium chloride, dried, heated to 300--400 DEG  C., and then extracted with benzene; finally, benzene is distilled from the extract, this yielding a thick oily product which imparts a green fluorescence to natural or synthetic lubricating oils.