Method of preparing a particulate refractory composition for use in the manufacture of foundry moulds and cores, corresponding uses, and reclamation mixture for thermal treatment

US11311931B2 · kind B2 · utility

Assignee

• HÜTTENES-ALBERTUS CHEMISCHE WERKE GESELLSCHAFT MIT BESCHRÄNKTER HAFTUNG · DE

Inventors

• Xin Li · Shandong, CN
• Christian Lustig · Düsseldorf, DE
• Mirko Reinold · Hannover, DE
• Maria Schweinefuß · Hannover, DE
• Nicolas Egeler · Krefeld, DE

Key dates

• Filing date: Sep 6, 2019
• Grant date: Apr 26, 2022
• Expiry date: Sep 6, 2039

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B22C5/185
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Described is a method of preparing a particulate refractory composition for use in the manufacture of foundry moulds and cores from spent foundry moulds or cores formed of refractory material and a binder containing water glass, the method comprising the following steps: providing broken material from spent foundry moulds or cores or preparing broken material from spent foundry moulds or cores, wherein the broken material comprises particles and/or aggregates of particles of refractory material having hardened water glass binder on their surface, mixing the broken material with particulate amorphous oxide comprising silicon dioxide in an amount of 85% by weight or more, based on the total amount of the particulate amorphous oxide, to give a mixture and subjecting the mixture to a heat treatment at a temperature of 400° C. or higher. Also described are a corresponding use, a reclamation mixture, and a method of making a foundry mould or core.