Abstract: Particulate refractory aggregate containing elutable alkali is treated with a particulate active clay having a particle size of less than 0.5 mm in order to reduce the level of the elutable alkali. Sand recovered from spent foundry moulds and cores produced from alkaline binders can be treated to reduce its elutable alkali content and then recycled for further foundry use.
Type:
Grant
Filed:
December 29, 1995
Date of Patent:
January 18, 2000
Assignee:
Borden France S.A.
Inventors:
Philippe Marie Toussaint, Patrick Robert Queval, Johannes-Adolf-Jacobus Geraedts, Jacques Andre Caumont