Solvay & Cie

Other

Interox International (societe Anonyme)

Paul Essemaeker

Pierre Ledoux

Nicholas A Troughton

Jean De Ceuster

Edmond Bouillet

Johan Devenyns

Alain Decamps

Marcel Robberechts

Marc Hoyos

Jean DeCeuster

Fran&ccedil;ois Desprez

Process for bleaching a chemical paper pulp to a brightness of at least 89&deg; ISO, consisting in subjecting the pulp to a treatment sequence of several stages including a final bleaching stage with hydrogen peroxide in alkaline medium carried out in the presence of at least one stabilising agent and at a consistency of at least 25% by weight of solids, the stages preceding this final stage having purified the pulp so that its manganese content does not exceed 3 ppm by weight with respect to the solids and that the pulp has been delignified beforehand to a kappa number not exceeding 5.

Multi-stage bleaching process having a final stabilized peroxide stage

Process for preserving the mechanical strength properties of chemical

Process for stabilizing solutions of peroxidic compounds used for bleaching. At least one polymer derived from an alpha-hydroxyacrylic acid, which contains units of the formula ##STR1## where R.sub.1 and R.sub.2 represent hydrogen or an alkyl group comprising from 1 to 3 carbon atoms which can be substituted by a hydroxyl group or a halogen atom, R.sub.1 and R.sub.2 being identical or different, and where M represents an alkali metal atom, a hydrogen atom or an ammonium group, is added to the solution as a stabilizer.

Process for stabilizing solutions of peroxidic compounds used for

A process for the reclamation of waste paper in the presence of an aqueous alkaline solution comprises having the solution contain at least a carboxylated polymer.

Process for the reclamation of waste paper

Growing community of inventors

Brussels, Belgium

Paul Essemaeker