Institut Polytechnique De Grenoble

Centre Technique De L'industrie Des Papiers, Cartons Et Celluloses

Jennifer Marcon

Michel Petit-Conil

Gérard Mortha

Auphelia Burnet

Nathalie Marlin

Gerard Mortha

Auphélia Burnet

The present invention relates to a method for bleaching an unbleached or pre-bleached paper pulp comprising at least the following consecutive steps: a) preparing an unbleached or pre-bleached paper pulp having a pH of at least 8, b) bringing the paper pulp obtained at the end of step a) into contact with chlorine dioxide, c) when the pH of the paper pulp obtained from step b) is lower than 10, adding at least one Br&#xf8;nsted base to the paper pulp, d) adding hydrogen peroxide to the paper pulp obtained at the end of step c), e) maintaining the paper pulp obtained at the end of step d) in a first bleaching tower, f) optionally, adding sulphuric acid to the paper pulp obtained at the end of step e) and maintaining the obtained paper pulp in a second bleaching tower, the method dispensing with the need for a step of washing the paper pulp before the end of step e), and, if applicable, before the end of step f).

Method for bleaching paper pulp

Growing community of inventors

Saint Pierre du Mont, France

Jennifer Marcon