| 摘要 |
PURPOSE:To simply produce calcium aluminate hydrate having a small and uniform particle size by pretreating an aqueous slurry contg. lime and aluminum hydroxide at a relatively low temp. for a proper time, heating the slurry and carrying out hydrothermal synthesis. CONSTITUTION:An aqueous slurry contg. lime and aluminum hydroxide in about (2.9-3.1)/1 molar ratio of CaO/Al2O3 and regulated to about 300-600g/l concn. [expressed in terms of Ca(OH)2+Al(OH)3] is prepd. The slurry is pretreated at <=60 deg.C for >=2hr, preferably at ordinary temp. for >=about 10hr form fine seeds are crystal nuclei for synthesizing calcium aluminate hydrate. The slurry is then heated and hydrothermal synthesis is carried out at >=70 deg.C for a prescribed time to form fine powder contg. 3CaO.Al2O3.6H2O as the principal component. Thus, fine powder of calcium aluminate hydrate having about 1-5mum particle size and <=about 2mum width is obtd. at a low cost.
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