Filter media and process to prepare the same

摘要

The invention concerns a process for filtering water comprising passing the water through a bed of a filter medium comprising 1 to 20% by weight of pre-hydrolyzed positively charged multivalent metallic species adsorbed on a solid substrate wherein said species has an OH to metal ratio between 0.5 and 3. The multivalent metal includes aluminium, iron, zinc, calcium or magnesium. The invention also concerns filter media comprising treating a solid substrate with an aqueous solution of a pre-hydrolyzed positively charged multivalent metallic species and an additional biocide..