摘要 |
A process for the preparation of stable, liquid aqueous solutions of basic aluminium nitrate (aluminium oxynitrate) suitable for spinning into fibres, if desired after incorporation of a polymeric spinning aid, which process comprises reacting an aluminium oxide with nitric acid at below 25 DEG C. to form aluminium hydroxide, optionally washing the precipitate to remove undesirable ions, e.g. sodium ions, and digesting the precipitate in nitric acid or aluminium nitrate. Preferably the solution contains aluminium ions and nitrate ions in the molar ratio 1.6:1 to 2:1. Silica may be incorporated in the solution by reacting it with the nitric acid, together with the aluminium oxide, in the first step of the process.
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