摘要:
A binder composition for producing articles of bonded particulate material such as foundry moulds or cores comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.
摘要:
A binder composition for producing articles of bonded particulate material such as foundry moulds or cones comprises an alkaline aqueous solution of a resol phenol-aldehyde resin and an oxyanion capable of forming a stable complex with the resin the amount of alkali present in the solution being sufficient to substantially prevent stable complex formation. Bonded articles are produced from mixtures of particulate material and the binder composition by passing carbon dioxide gas through the formed articles whereby the oxyanion forms a stable complex with the resin and the resin is cured. The oxyanion may be for example borate, stannate or aluminate.
摘要:
Fermentation process, e.g. for the production of an oxidation product such as vinegar, which comprises continuously cultivating a bacterial strain, preferably in a vessel of elongated shape, in a medium containing the substrate to be fermented in the presence of a hydrous oxide of a metal selected from the group consisting of titanium, vanadium, zirconium, iron and tin and a chelated polyhydroxy support. The bacterial strain used in the process is preferably chelated or complexed with the hydrous metal oxide and the polyhydroxy support.