| 摘要 |
<p>An ion exchanger which fixes ions of caesium, barium, and rubidium is composed of granular particles of zirconium phosphate containing up to 60% by weight based upon the total weight of the composition of the potassium or ammonium salt of a heteropolyacid, e.g. phosphomolybdic or phosphotungstic acid. The exchanger is prepared by the addition of phosphoric acid and an aqueous zirconium salt solution, e.g. zirconyl chloride, with stirring to an aqueous suspension of the phosphomolybdate or phosphotungstate with stirring, the zirconium ion concentration being usually lower than 18g per litre of suspension and the phosphoric acid having a concentration of 1N to 6N and being in excess, the precipitate is then filtered, washed with dilute nitric acid and dried at about 110 DEG C.</p> |
