Patent GB-777876-A (GB)
Title: Improvements relating to the production of sebacic acid compounds and if desired by-product compounds from ricinoleic compounds
IPC: C07C29/00
Filed: 1955-01-21
Abstract: Sebacic acid compounds and, if desired, by-product compounds are obtained from ricinoleic compounds by reacting the ricinoleic compounds with alkali metal hydroxide and water, including the water formed in situ when the ricinoleic compound is ricinoleic acid, at elevated temperature, preferably at a temperature of about 225 DEG to 375 DEG  C., in the presence of a lead compound and/or a barium compound, the reaction mixture being maintained in fluid condition. The lead compound is preferably used in an amount of from 1 to 20 per cent by weight (calculated on the basis of PbO) of the ricinoleic compound and the barium compound is preferably used in an amount of from 0.5 to 5.0 mols. for each ricinoleic radical present.  The ricinoleic compound used is preferably an alkali ricinoleate, i.e. a ricinoleic salt of an alkali or alkaline earth metal, e.g. sodium, potassium, lithium, calcium, or barium.  Other ricinoleic compounds which may be used include esters such as castor oil, methyl ricinoleate, capryl ricinoleate and propylene glycol ricinoleate; ricinoleic acid, ricinoleic acid amides, ricinoleyl alcohol, and ricinoleyl alcohol esters.  The lead compounds are preferably inorganic lead compounds or lead salts of organic acids, specified lead compounds being the monoxide, dioxide, sesquioxide and suboxide, red lead, lead oxychloride, lead chloride, lead tetrachloride, lead carbonate, lead hydroxide, and the orthophosphate, metaphosphate, pyrophosphate, phosphite, sulphate, acetate, phenolate, benzoate, oxalate, citrate, tartrate, ricinoleate, heptanoate, undecenoate, laurate, stearate, and 12-hydroxystearate.  The barium compound may be a water-soluble ionizable barium compound or a barium compound which is converted into such ionizable compound under the reaction conditions, specified compounds being the hydroxide, oxide, chloride, bromide, iodide, hypophosphite, ricinoleate, formate, acetate, propionate, and phenolate.  The alkali metal hydroxide is preferably employed in stoichiometric excess, e.g. 5.0 to 20 mols. of the alkali metal hydroxide may be used for each ricinoleic radical present. When ricinoleic compounds other than alkali salts are used as starting materials, sufficient additional alkali to form the alkali salt should be present in the mixture introduced into the reactor. The amount of water present should be from about 4 to 5 moles. per ricinoleic radical present and the water may be added during the course of the reaction or introduced in the form of steam or superheated steam.  The reaction is normally effected under partial reflux conditions, the volatile reaction products and water vapour being taken off overhead.  The principal volatile product, capryl alcohol, is recovered along with any other condensable products, such as methyl hexyl ketone by passing the volatiles through a condenser system.  The process may be carried out batchwise or in a continuous manner.  When barium compounds are used with or without lead compounds, the insoluble barium sebacate is formed in the reaction and may be separated by filtration and acidified with a mineral acid, e.g. hydrochloric acid, to form sebacic acid.  Examples are given for the production of sebacic acid from: (1) sodium ricinoleate using sodium hydroxide, water (introduced in the form of superheated steam) and red lead or litharge; (2) methyl ricinoleate using lithium hydrate, water (introduced in the form of superheated steam) and lead chloride; (3) ricinoleyl alcohol using sodium hydroxide, water (introduced in the form of superheated steam) and lead phenolate; (4) methyl ricinoleate using sodium hydroxide in the presence of water, and barium hydroxide or barium chloride; (5) ricinoleic acid (or castor oil) using sodium hydroxide in the presence of water and barium hydroxide; (6) barium ricinoleate using sodium hydroxide in the presence of water, the barium ricinoleate providing both the ricinoleic compound and the added barium compound; (7) ricinoleyl alcohol using potassium hydroxide in the presence of water and barium hydroxide; (8) methyl ricinoleate using lithium hydroxide in the presence of water and barium hydroxide; (9) sodium ricinoleate (or methyl ricinoleate) using sodium hydroxide in the presence of water and barium hydroxide; (10) barium ricinoleate using sodium hydroxide in the presence of water and barium chloride; (11) barium ricinoleate in the presence of water, barium chloride and red lead, litharge, lead dioxide, or lead acetate; (12) lead ricinoleate using sodium hydroxide in the presence of water and barium chloride; (13) methyl ricinoleate using sodium hydroxide in the presence of water, barium hydroxide and lead chloride; (14) ricinoleyl alcohol using potassium hydroxide in the presence of water, barium hydroxide and lead phenolate; (15) sodium ricinoleate using sodium hydroxide in the presence of water, barium hydroxide and with or without lead dioxide. Capryl alcohol is also referred to as a product in most of the examples. Comparative examples are also given in which sebacic acid and capryl alcohol are obtained from sodium ricinoleate using sodium hydroxide in the presence of water (introduced in the form of superheated steam).