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公开(公告)号：EP1345681A1
公开(公告)日：2003-09-24
申请号：EP01999426.8
申请日：2001-12-07
IPC分类号： B01J13/00
CPC分类号： B01J13/0013 , B01J13/0039 , Y10S977/773
摘要： The invention concerns a rare earth colloidal dispersion and its preparation method. The dispersion is characterised in that it comprises anisotropic and disaggregated particle, or capable of being disaggregated, of at least a rare earth and a water-soluble monovalent acid anion having a pKa of at least 2.5. It is prepared by a method which consists in: mixing a solution of at least a rare earth salt with phosphate ions controlling the pH of the reaction medium at a value ranging between 4 and 9 and in the presence of a water-soluble monovalent acid having a pH of at least 2.5; optionally ripening the resulting mixture; separating the precipitate from the reaction medium: re-dispersing in water said precipitate.
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公开(公告)号：EP1173448A1
公开(公告)日：2002-01-23
申请号：EP00926363.3
申请日：2000-04-25
发明人： YUNLU, Kenan , HE, Min
CPC分类号： C07F9/025
摘要： Stable rare earth tris (organophosphate) solutions comprise a rare earth tris (organophosphate) and a hydrocarbon solvent. From about 2 % to about 10 % rare earth element, preferably from about 3 % to about 8 %, is present in the solutions. The rare earth tris (organophosphate) solutions are stable from precipitation of the rare earth tris (organophosphate) for at least about fifteen (15) days, preferably for at least about twenty (20) days and most preferably at least about thirty (30) days. A process for preparing these solutions is described herein. A stabilizing additive, acid, glycol or mixtures thereof, is utilized to inhibit precipitation. The molar ratios of free acid, glycol and/or water to the rare earth element are controlled to inhibit precipitation.
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