Patent GB-748401-A (GB)
Title: Improvements in and relating to the alcoholysis of glycerides
Inventor: COATS ROBERT REID
IPC: C11C3/04
Filed: 1952-10-09
Abstract: Esters are produced by heating glycerides of those fatty acids containing 8 or more carbon atoms at a temperature not exceeding 300 DEG  C. with one or more monohydric alcohols containing a straight chain of 8 or more carbon atoms in the presence of an alcoholysis catalyst and an inert liquid diluent which is a solvent for the glyceride or glycerides and the alcohol or alcohols to be reacted, but which is immiscible with glycerol, whereby glycerol liberated in the process is distilled out of the reaction mixture in the vapour of the liquid diluent.  Preferably the diluent is also a solvent for the esters produced.  Suitable liquid diluents include petroleum hydrocarbons, cyclic hydrocarbons, heavy naphthenes, chlorinated hydrocarbons or aromatic nitro compounds, said diluents boiling in the range 145 DEG  to 285 DEG  C.  Alternatively, a mixture of alcohols produced by the hydrogenalysis of the glycerides may be used both as alcoholic reactant and liquid diluent, an excess of over the stoichiometric amount required to react with the glyceride being employed. Suitable alcoholysis catalysts are the oxides, alcoholates, hydroxides and carbonates of the alkali and alkaline earth metals and magnesium, mineral acids such as sulphuric and phosphoric acids, and organic sulphonic acids, such as p-toluene sulphonic acid and camphor sulphonic acid.  The process is suitably effected at temperatures of 100 DEG -300 DEG  C., preferably 150 DEG -250 DEG  C., and at atmospheric, reduced or increased pressure.  The ester products are in the form of waxes and may be used as polishing agents, for producing protective layers or for pharmaceutical preparations.  In Examples: (1) octadecanol is refluxed with rape oil in the presence of sodium hydroxide and tetrahydronaphthalene until glycerol ceased to be distilled over, whereafter the product is recovered by filtration through kieselguhr under vacuum followed by distillation to remove the solvent; palm kernel alcohols are refluxed with palm kernel oil in the presence of sodium hydroxide using as liquid diluent (2) tetrahydronaphthalene, or (3) excess palm kernel alcohols.ALSO:Glycerine is produced by heating glycerides of fatty acids containing 8 or more carbon atoms at a temperature not exceeding 300 DEG C. with one or more monohydric alcohols, containing a straight chain of 8 or more carbon atoms, in the presence of an alcoholysis catalyst and an inert liquid diluent which is a solvent for the glyceride or glycerides and the alcohol or alcohols to be reacted, but which is immiscible with glycerine, whereby the glycerine is distilled out of the reaction mixture in the vapour of the liquid diluent.  The glycerine may be separated from the liquid diluent, for example by decantation in the cold, and purified by distillation.  Preferably the diluent used is also a solvent for the esters produced by alcoholysis.  Suitable liquid diluents include petroleum hydrocarbons, cyclic hydrocarbons, heavy naphthese, chlorinated hydrocarbons or aromatic nitro compounds, said diluents boiling in the range 145 DEG  to 285 DEG C.  Alternatively, a mixture of alcohols produced by the hydrogenolysis of the glycerides may be used both as alcoholic reactant and liquid diluent, an excess over the stoichiometric amount required to react with the glyceride being employed.  Suitable alcoholysis catalysts are the oxides, alcoholates, hydroxides and carbonates of the alkali and alkaline earth metals and magnesium, mineral acids such as sulphuric and phosphoric acids, and organic acids such as p-toluene sulphonic acid and camphor sulphonic acid.  The process is suitably effected at temperatures of 100 DEG -300 DEG C., preferably 150 DEG -250 DEG C., and at atmosphere, reduced or increased pressure.  In examples, (1) octadecanol is refluxed with rape oil in the presence of sodium hydroxide and tetrahydronaphthalene until glycerine ceases to be evolved; (2) palm kernel alcohols are refluxed with palm kernel oil in the presence of sodium hydroxide using as liquid diluent tetrahydronaphthalene or (3) excess palm kernel alcohols, whereupon glycerine is evolved with the entrainer.