Patent GB-835208-A (GB)
Title: Process for the preparation of sebacic acid and/or 10-hydroxydecanoic acid from ricinoleic acid and its derivatives
IPC: C22C28/00
Filed: 1956-09-12
Abstract: Salts of sebacic acid and/or 10-hydroxy-decanoic acid, together with 2-octanol or 2-octanone, is/are produced by heating a salt, especially an alkali metal salt, of ricinoleic acid with water and when the intended product is the salt of sebacic acid, with alkali metal hydroxide, at an elevated temperature and in the presence as catalyst of lead, bismuth, thallium or an alloy containing one or more of these metals or a compound of bismuth or thallium or a mixture of a compound of lead, bismuth or thallium with a compound of a metal which forms an alloy with lead, bismuth or thallium. The starting material salts may be formed in situ by reaction of castor oil with alkali.  Preferred temperatures are 160-190 DEG  C. for preparing hydroxydecanoic acid and 250-350 DEG  C. for sebacic acid. Liquid water, preferably 3-20 mols. per mol. of ricinoleic acid, under pressure, e.g. 10-200 kg/cm.2, may be used or steam at lower pressure or at atmospheric pressure.  Alkali metal soaps may be added.  0.05 to 20% or more of catalyst metal by weight referred to ricinoleate may be used.  The whole of the ricinoleate may be present as its salts with the catalyst metals. The catalysts may be added as the free metals or as compounds, preferably those reduced to the free metal under the reaction conditions, e.g. as carbonates, bicarbonates, oxides, hydroxides, halides, sulphites, sulphates, phosphates, nitrites, nitrates, carboxylates, sulphonates, &c.  Where the metal is amphoteric it may be added as an anion, e.g. plumbates and plumbites. Organometallic compounds may also be used, e.g. lead tetraethyl, diphenyl lead, &c.  It is advantageous to use alloys of the catalyst metals amongst themselves or with other metals such as cadmium, indium, tin and antimony, especially those melting below 300 DEG  C., preferably below 200 DEG  C., which may be separated from the reaction mixture in the liquid state.  Examples are given containing at least 5, preferably 10-95% of active metal (see Group II).  In numerous examples, sebacic and/or 10-hydroxydecanoic acid is/are prepared from castor oil or castor oil acids, water and alkali metal hydroxide in the presence of various catalysts in a stirred autoclave in an inert atmosphere of N2 or H2 under pressure; by a continuous process in a reaction coil; or at atmospheric pressure using steam instead of liquid water.  Specifications 736,413 and 777,876 are referred to.ALSO:Alloys are described, used as catalysts in the preparation of sebacic and 10-hydroxydecanoic acids from ricinoleic acid (see Group IV(b)).  Specified compositions are (numbers = % by weight): 10-75 Pb, rest Sn, 82.5 Pb + 17.5 Cd; 87 Pb + 13 Sb; 63 Tl + 17 Cd; 38 Pb + 62 Sn; 62 Bi + 38 Cd; 58 Bi + 42 Sn; 44 Pb + 56 Bi; 60 Bi + 30 Cd + 10 Tl; 53 Bi + 26 Sn + 21 Cd; 52 Bi + 32 Pb + 16 Sn; 50 Bi + 25 Pb + 25 Sn; 50 Bi + 30 Pb + 20 Sn; 50 Bi + 26.7 Pb + 13.3 Sn + 10 Cd; 50 Bi + 25 Pb + 12.5 Sn + 12.5 Cd; 40.95 Bi + 22.10 Pb + 18.10 In + 10.65 Sn + 8.20 Cd.  In numerous examples, catalyst alloys are formed in situ by heating ricinoleic acid salts, water and alkali metal hydroxide with the following mixtures: PbCl2/CdO; Bi(NO3)3.SH2O/CdO; BiCl3/CdO; BiCl3/PbCl2/CdO; Bi(NO3)3 5H2O/PbCl2/CdO; TlNo3/CdO; PbCl2/SbCl3 PbCl2/TlNO3.