Abstract: A water treatment system for submersion in a body of water to be treated comprises a water-soluble glass treatment agent and a water-insoluble retaining means for the water-soluble glass treatment agent. The retaining means is adapted, in use, to retain water in contact with the water-soluble glass and may be a hollow container for the water-soluble glass or a moisture penetrable polymer composition which can be used as a matrix containing particulate water soluble glass. The water-treatment system may be immersed in water to act over an extended period of time in preventing or reducing problems caused by corrosion, scaling and/or fouling.

Abstract: A binder composition for binding a water-insoluble particulate material, such as sand, in the manufacture of a foundry mold or core comprises a mixture of (1) an inorganic binder consisting of an aqueous solution containing polyphosphate chains and/or borate ions and (2) a water-soluble surfactant. The inclusion of a water-soluble surfactant improves the flowability of foundry molding compositions.