Calgon Carbon Corporation

Richard W Farmer

Thomas M Matviya

Netar P Wadhwa

Susan L Kovacic

Richard A Hayden

Robert H Vaughn

Bertrand W Dussert

Charles Joseph Carr

Brett Leslie Pinker

An improved filter is provided for lowering levels of contaminants in domestic drinking water. The filter contains an oxidized activated carbon and at least one other type of adsorbent to remove cationic species and at least one other contaminant. The filter further achieves an efficient use of the adsorbents by including an envelope containing part or all of the adsorbents, which envelope minimizes the potential for flow by-pass.

Filter for purifying domestic drinking water

An improved process is provided for the manufacture of N-phosphonomethylglycine from N-phophonomethyliminodiacetic acid in the presence of a molecular-oxygen containing gas utilizing a catalytically active carbonaceous char produced at low temperature. The improvement is provided by the use of a carbonaceous char capable of rapidly decomposing hydrogen peroxide in an aqueous solution.

Method for the manufacture of N-phosphonomethylglycine from

Treatment of a wet activated carbon with carbon dioxide or with carbon dioxide followed by air results in a carbon having a reduced contact pH. The activated carbon is characterized by a modified contact pH less than about 9.0 and typically between about 7.3 and 9.0. Use of this carbon in a water treatment system eliminates the excessive effluent water pH rise which commonly occurs with activated carbon. Also use of this carbon in a water treatment system reduces the aluminum concentration of the water when compared to an untreated carbon.

Activated carbon treated by carbon dioxide for the stabilization of

Treatment of a wet activated carbon with carbon dioxide or with carbon dioxide followed by air results in a carbon having a reduced contact pH. The activated carbon is characterized by a modified contact pH less than about 9.0 and typically between about 7.3 and 9.0. Use of this carbon in a water treatment system eliminates the excessive effluent water pH rise which commonly occurs with activated carbon.

An oxidized activated carbon having a contact pH between 7.1 and 8.2 for general use in aqueous treatment systems to prevent pH and alkalinity excursions during start-up of the system and an oxidized activated carbon having a contact pH between 6.0 and 9.5 for specific use in aqueous treatment systems to control pH and alkalinity changes during water treatment.

Growing community of inventors

Gibsonia, PA, United States of America

Richard W Farmer