Patent EA-000851-B1 (EA)
Title: Organic sol comprising at least one oxygenated rare-earth compound, synthesis method therefor, and use of said sol for catalysis
Inventor: BIRCHEM THIERRY
IPC: C01F17/241
Filed: 1996-11-22
Abstract: 1. A method for preparing colloid dispersion from an aqueous phase, comprising at least one oxygen-compound containing rare-earth metal, comprising an oxygen compound of said metal in the presence of an organic solvent and an amphiphilic system with consecutive recovering of the colloid dispersion, characterized in that the aqueous phase is a dispersion of at least one oxygen compound of at least one rare-earth metal, having a dispersion ability in water of at least 50% and prepared by precipitating an acetate and/or a chloride of said metal in a basic medium with subsequent atomisation or lyophilisation of the prepared oxygen compound, wherein an amount of particles greater than 0,1 micrometer in size is preferably not more than 5%. 2. A method according to claim 1, characterized in that an oxygen-containing metal is a compound based, at least, on one rare-earth element, and, at least, on another element selected from groups IVA, VIIA, VIII, IB, IIB, IIIB and IVB of the Periodic Table of the Elements and in that a mixture is prepared containing, at least, one acetate or a choride of a rare-earth metal, and, at least, one salt or one sol of said element; contacting said mixture and the basic medium and maintain the obtained reaction medium at a basic pH; recovering the precipitationformed by atomisation or lyophilisation. 3. A method according to claim 1 or 2, characterized in that an oxygen-containing metal is a compound based, at least, on one rare-earth element selected from yttrium, neodymium, gadolinium and praseodymium. 4. A method according to claims 1-3, characterized in that an oxygen-containing metal further contains, at least, one another element selected from zirconium, iron, copper, gallium, palladium and manganese. 5. A method according to claims 1-4, characterized in that maintains constant pH of the reaction medium wherein contacting a solution or said mixture with the basic medium. 6. A method according to claims 1-5, characterized in that realises said contacting by introduction of the solution or said mixture into the basic medium. 7. A method according to claims 1-6, characterized in that a solution of ammonium hydroxide is used as the basic medium. 8. A method according to claims 1-7, characterized in that pH of the basic medium is maintained at, at least, 9, preferably from 9,5 to 11. 9. A sol comprising particles of oxygen-containing compound of a rare-earth metal, amphiphiic acid system and an organic solvent, characterized in that the particles of the oxygen-containing compound of said metal are obtained by precipitating of acetate and/or chloride of said metal in the basic medium with subsequent atomisation or lyophilisation of the prepared compound and have a dispersion ability in water of at least 50%, wherein an amount of particles greater than 0,1 micrometer in size is preferably not more than 5%. 10. A sol according to claim 9, characterized in that a molar ratio between amphiphilic acid system and metal elements is not more than 0,5. 11. A sol according to claim 9 and 10, characterized in that a lateral chain or lateral chains of acids representing at least one ramification contain at least 2 carbon atoms, preferably not less than 3. 12. A sol according to claims 9-11, characterized in that said amphiphilic acid system contains isostearic acid. 13. A sol according to claims 9-12, characterized in that said amphiphilic acid system is an ester of phosphoric acid. 14. A sol according to claims 9-13, characterized in that a fusion temperature of said amphiphilic acid system is not more than 50 degree C, preferably 20 degree C, more preferably 0 degree C. 15. A sol according to claims 9-13, characterized in that said particles of tetravalent oxide, the size of which is more than 0,1 micrometer, preferably 0,05 micrometer, more preferably 0,02 micrometer, constitute not more than 5%, preferably not more than 1%, more preferably not more than 0,5% wt. 16. A sol according to claims 9-13, characterized in that a diluent contains not more than 50%, preferably not more than 1/5 of aromatic hydrocarbon. 17. Fuel for internal combustion engine, characterized in that obtained by mixing conventional fuel with sol according to one of claims 9-16. 18. Use of sols as an additive to gas oil for diesel engine.