1 Chemical products, biological preparations, bacteriological preparations used for water treatment, water purification and treatment of industrial effluents; filtering material; ceramic material for filtration; ceramic material for reverse osmosis; chemical products for industrial treatment of liquids; ion exchangers; organic and/or inorganic chemical products, particularly in ceramic material used particularly for the manufacturing of filtering éléments, filters, filtering or reverse osmosis membranes; chemical products, catalysts, additives, chemical intermediates, active principles, purified extracts of natural essence for use in the following industries: pharmacology, cosmetics, electronics, foodstuffs, colourants, textiles, paints, glass goods, nuclear engineering, metallurgy and plastics; ion exchangers (chemical products) for cleaning and sterilizing resins; chemical products and fluids, particularly eluents for chromatography and crystallography, particularly for preparative and analytic chromatography; liquid, semi-liquid or gas chromatography; chemical products for separation, purification and fractionation by chromatography; intermediary products for the synthesis of pharmaceutical, veterinary, sanitary and cosmetic active principles