Abstract: Sodium percarbonate exhibits a tendency to decompose in built compositions and particularly detergent compositions built with zeolites. The tendency can be ameliorated by selecting sodium percarbonate which intrinsically has a mean particle size of from 500 to 1000 microns and not more than 20% by weight of below 350 microns and has a moisture pick-up when measured in a test at 80% relative humidity and 32° C. after 24 hours of not greater than 30 g/1000 g sample. A suitable sodium percarbonate can be made most conveniently by crystallisation from a bulk saturated solution of sodium percarbonate in a crystalliser/classifier that does not employ a conventional chloride salting-out agent.
Type:
Grant
Filed:
March 30, 1999
Date of Patent:
October 23, 2001
Assignee:
Solvay Interox
Inventors:
Alun P. James, Graham R. Horne, Richard Roesler, Soraya Parvaneh, Romano Pardini, Pier-Luigi Deli
Abstract: The present invention concerns a process for the production of hydrogen peroxide by reacting a gas mixture which contains hydrogen and oxygen in an aqueous reaction medium containing less than 2% by volume liquid organic components and in the presence of a metallic catalyst which is characterized in that a palladium/gold alloy with 5 to 95 atom percent gold or a palladium/iridium or palladium/rhodium bimetal with 1 to 15 atom percent iridium or rhodium is used as the catalyst.
Type:
Grant
Filed:
December 2, 1994
Date of Patent:
April 9, 1996
Assignee:
Solvay Interox
Inventors:
Udo Luckoff, Heinrich Paucksch, Gerhard Luft
Abstract: Method for the direct synthesis of an aqueous solution of hydrogen peroxyde from hydrogen and oxygen by hydrogenous catalysis in a three-phase system in which the hydrogen and oxygen are reacted directly in a gas state, at a pressure above atmospheric pressure, on the surface of a solid hydrogenous catalyst in suspension in a granular state in an aqueous liquid phase, said catalyst consisting of a metal compound selected from pure palladium or an association of palladium with at least one other noble metal, and impregnated on a substrate comprising at least one compound selected from alkaline-earth metal sulfates or phosphates. A catalyst is disclosed for the production of an aqueous liquid phase of hydrogen peroxyde consisting of a metal compound selected from pure palladium or an association of palladium with at least one another noble metal, and impregnated on a substrate comprising at least one compound selected from alkaline-earth metal sulfates or phosphates.
Type:
Grant
Filed:
October 4, 1993
Date of Patent:
September 5, 1995
Assignee:
Solvay Interox
Inventors:
Jacques Van Weynbergh, Jean-Paul Schoebrechts, Colery: Jean-Claude
Abstract: A process for delignifying a lignocellulosic material comprising exposing the material to a mixture of peracid and ozone. Preferred peracids include Caro's acid and peracetic acid. Also disclosed is a kraft pulp delignification mixture comprising in combination: (a) water; (b) a kraft pulp at 1-40% consistency; (c) a peracid; and (d) from 0.1 to 5.0% ozone on pulp.
Type:
Grant
Filed:
March 22, 1993
Date of Patent:
May 2, 1995
Assignees:
The Research Foundation of State University of New York, Solvay Interox
Inventors:
Raymond C. Francis, Xioa-Zhu Zhang, Nicholas A. Troughton
Abstract: Reaction of amine-containing substrates with hydrogen peroxide can suffer from certain problems, especially in the presence of transition metals. These problems include both in situ generation of impurities and particularly nitrosamines, which are allegedly carcinogenic, and also impaired product formation. The problems can be ameliorated by employing in the reaction mixture free radical scavengers, including in particular phenols and polyhydroxy-substituted aromatic compounds. The scavengers are advantageously employed in conjunction with a metal chelating agent such as polycarboxylic acid or an organopolyphosphonic acid.