The outer shell of the TF321/TFE500 cartridge is a high quality, micro-porous ceramic media which traps out, not only silt and debris, but pathogenic bacteria and protozoan cysts. The ceramic is manufactured at Katadyn’s modern factory in Switzerland, where carefully selected raw materials are subjected to a precisely controlled manufacturing process to produce the high quality ceramic filter media. Katadyn’s experience in this field of technology is second to none. They have been involved with water treatment since 1928 and their products, as befits the Swiss reputation, are renowned for their consistency and reliability. There are many manufacturers of ceramic water filters around the world but few, if any, manufacture to the same fine-pore structure consistency and exacting levels of quality control. When dealing with pathogenic microorganisms, quality is paramount and only the best will do!

Katadyn’s ceramic is impregnated with silver during the manufacturing process. Silver is a bactericide. It has been known for centuries that silver is an appropriate material for water containers. The Romans used to store their drinking water in silver vessels. It is only over the last hundred years or so that the microbiology of water has been understood and that the effectiveness of disinfectants has been assessed. The bactericidal action of silver is called the “oligodynamic” effect from the Greek “oligos” meaning small and “dynamis” meaning action. The silver ions released from the ceramic in very low concentrations attack the DNA and enzymes in the bacteria which prevents their reproduction. When added to the ceramic, the silver acts bacteriostatically, that is it inhibits the growth of bacteria in the ceramic.

The activated carbon, within the core of the Katadyn ceramic, is manufactured by extruding a mixture of granular activated carbon and polyethylene powder at an elevated temperature so that the activated carbon particles bind together to form a tight matrix. The carbon block manufacturing process is precisely controlled to ensure that the pore structure is consistent so that water flows uniformly through it. The bituminous coal based activated carbon used is carefully selected and graded to give the optimum adsorption properties for domestic applications. Water passes through the ceramic wall and then through the carbon block. As it does, organic contaminants in the water diffuse into the structure of the carbon granules and are adsorbed. Chlorine is also effectively removed but by conversion to the chloride ion by reaction at the carbon surface. The TF321/TFE500 is sized so that it will treat a normal domestic drinking water application for at least six months.

A pulverised synthetic zeolite or inorganic cation exchange material is intermixed with the activated carbon prior to its extrusion. The zeolite has the capability to reduce lead present in water.

Thus the composite TF321/TFE500 filter cartridges have the capability in one small unit, to remove/reduce: