In M-SG an alkali metal is absorbed into silica gel at elevated temperatures. The resulting black powder material is an effective reducing agent and safe to handle as opposed to the pure metal. The material can also be used as a desiccant and as a hydrogen source.[1]
The metal is either
Na2K). The molten metal is mixed with silica gel under constant agitation at room temperature. This phase 0 material must be handled in an inert atmosphere. Heating phase 0 at 150 °C (302 °F) takes it to phase I. When this material is exposed to dry oxygen the reducing power is not affected. At further heating to 400 °C (752 °F) phase II can be handled safely in an ambient environment. M-SG reductions: benzyl chloride reduction to bibenzyl, dibenzothiophene reduction to biphenyl and naphthalene reduction to dihydronaphthalene
