CHEMICAL PREPARATIONS IN THE NATURE OF INORGANIC FILTERING MATERIALS FOR USE IN THE FOOD-PROCESSING, BIO-INDUSTRY, CHEMICAL AND PETROCHEMICAL INDUSTRIES; MINERAL SUBSTANCES IN THE NATURE OF INORGANIC FILTERING MATERIALS FOR USE IN THE FOOD-PROCESSING, BIO-INDUSTRY, CHEMICAL AND PETROCHEMICAL INDUSTRIES; UNPROCESSED PLASTICS IN THE NATURE OF INORGANIC FILTERING MATERIALS FOR USE IN THE FOOD-PROCESSING, BIO-INDUSTRY, CHEMICAL AND PETROCHEMICAL INDUSTRIES; INORGANIC CERAMIC PARTICLES FOR USE AS ...