Treatment of Calcium aluminate(s) loaded with hazardous substances

摘要

Laminar Ca aluminates loaded with hazardous substances, after use for absorption of organic hazardous substances and heavy metals, is treated to recover components of the aluminate and to mfr. new laminar aluminates. The Ca aluminate is adjusted to a pH of 1-6, Ca is pptd. as Ca sulphate and filtered off, and the pH value of the soln. is increased to 5-8, so that Al is pptd. as Al(OH)3. This is filtered off and Ca aluminate or Na aluminate is formed by addn. of water and Ca(OH)2 at 70-80 deg C or NaOH at 70-90 deg C.