| 摘要 |
PURPOSE: To obtain the alumina with which a white ceramic ware is obtained from a low-grade material by adding hydrochloric acid to a crushed spent catalyst carrying alumina, heating the obtained slurry, separating solid from liq., filtering off the hydrochloric acid component from the obtained solid, drying and then crushing the solid. CONSTITUTION: The spent catalyst carrying alumina is crushed by a ball mill, etc., to <=30 mesh, >=1N hydrochloric acid is added to the crushed material in an acid-resistant and heat-resistant vessel and mixed until a slurry is obtained. The slurry is agitated and heated, solid is separated from liq. by a filter, and the separated wet solid is again charged into the vessel to remove the residual hydrochloric acid component, added with water, agitated, cleaned and filtered off in the same way as before. The wet solid is placed in a flat heat-resistant vessel, dried by vaporizing the moisture and crushed to <=100 mesh, for example, to obtain the desired alumina. The alumina is mixed with an iron-contg. low- grade material such as a stoneware clay, and the material is press-formed, dried and fired to obtain a white ceramic. |
