PROCESS FOR PRODUCING LANTHANUM CARBONATE HYDRATES AND PHARMACEUTICAL COMPOSITION CONTAINING THEM

摘要

Hydrated lanthanum carbonate of the general formula La2 (CO3) 3.xH2O, containing a limited amount of crystalline water, wherein in the above general formula x is from 3 to 6, and preferably from 3.8 to 4.5. The invention further relates to said pharmaceutical compositions containing said hydrated lanthanum carbonate and to a process for the preparation of said hydrated lanthanum carbonate. Said hydrated lanthanum carboxylate according to the invention is prepared by: a) reacting lanthanum oxide with a oleic acid which slurries the lanthanum salt sa b) reacting the resulting lanthanum salt oil with an alkali metal carbonate to produce a lanthanum carbonate acetic anhydrate in a wet filtered master; and c) drying the wet, filtered lanthanum carbonate acetic anhydrate to provide 3-6 mol of lanthanum carbonate in crystalline water. ŕ