摘要 |
Cores made from Alumina and other non-Silica based refractories can be made readily leachable in fused anhydrous caustic alkalis by the addition to the core of a small quantity of a material containing a Hydrogen donor group. The Hydrogen donor group is one which produces uncombined, or nascent Hydrogen when the ceramic is contacted with the anhydrous caustic alkali. Such groups are Hydroxyl groups, Hydrides or chemically combined water. In one disclosed example Silica which contains traces of water is added to high fired Alumina to provide the Hydrogen donor group. Only 2% to 3% Silica addition is required to make the Alumina readily soluble in the fused alkali.
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