Improvements relating to the preparation of compounds of titanium and zirconium

摘要

569,054. Zirconium and titanium salts. EVERY, C. E. (Titanium Alloy Manufacturing Co.). May 3, 1943, No. 6986. [Class 1 (iii)] Salts of zirconium or titanium are prepared by adding an acqueous solution of a salt of the element to a solution of an alkali metal or ammonium carbonate, stirring, separating and washing the precipitate (a carbonate of indeterminate composition), and adding the washed precipitate to an aqueous solution of an acid having a dissociation constant greater than that of carbonic acid. Acids with which the reaction may be obtained include the following : hydrochloric, nitric, sulphuric, formic, lactic, citric, acetic, oxalic, tartaric, benzoic, salicylic, chloracetic, malic, succinic, sulphanilic, cinnamic and picric. The salts have the general formula (ZrO)nX2 or (TiO)nX2, where X is the acid radical and n its valency. In the formation of the zirconium carbonate it is preferred to adjust the mixture to pH 6-7, and in the case of titanium carbonate, to pH 7-8. When using zirconium sulphate, the solution may be neutralized before adding to the carbonate solution. In a modification, zirconium carbonate is made by dispersing zirconium hydrate in water and passing in. carbon dioxide under pressure or not, or by adding solid carbon dioxide to the suspension in a pressure bottle. Octyl alcohol may be added as an anti-frothing agent during either stage of the process. A small amount of formaldehyde, e.g. 0.01-0.1. per cent may be added to the final product or its solution to prevent mould growth. Examples describe the preparation of zirconium salts of acetic, oxalic and racemic tartaric acid, and the titanium salt of oxalic acid.