Spherical gamma:alumina granules prodn. for use as adsorbent - by spraying hydrargillite or bayerite with water, heating under pressure, drying and reactivating

• Main Authors: MATYASI,JOZSEF,DR, KOEKENY,BELA,DR, KAPTAY,GYOERGY, ZSEMBERY,LASZLO,DR, NEMETH,SANDOR
• Format: Patent
• Language: English; German
• Published: 10.07.1980
• Edition: 2
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; INORGANIC CHEMISTRY; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

Prodn. of spherical gamma-alumina with great mechanicalstrength, useful as adsorbent, involves granulation of activated hydrargillite (IA) and/or bayerite (IB) with water, heat treatment at 90-95 degrees C, drying and reactivation. Granulation of (I), which has average size 15-20 mu and range 1-100 mu, is carried out by spraying with 0.15-0.35 (0.20-0.25) pts. wt. water/pt. (I) under a pressure of 1.8-2.2 at g. After prewetting with water, (I) and water are added alternately in 4-6portions in constant amts., with continuous stirring, then size of portions is increased until desired particle size is attained. Remaining water, max. 3 wt. % of total, is sprayed onto granulate during compression for 45-60 (50) min., then heat treatment is carried out for 8-18 (16) h at 90-95 degrees C and 1.5-2.5 at.g. This is followed by drying and reactivatoin. Prodn. is suitable for adsorption of vapurs, gases and liqs. and for deodorisation and purificn. of air. Its compression strength is 20-22 kg/mm2m cf.9-10 kg/mm2 for the highest grade prods. already available, whilst its water adsorption capacity is 22-32 wt. %.