Process for purifying alkali metal metaborate solutions and alkali metal perborate prepared from these solutions.

摘要

Solutions of alkali metal metaborate are purified by being clarified by removing suspended particles which have a diameter of less than 10 mu m and more than 0.2 mu m. The suspended particles are removed by centrifuging or by microfiltration on a membrane. The metaborate solutions obtained are clear and colourless and can be employed for the preparation of perborates with a view to their being incorporated in washing-aid products.