| (19) |
 |
|
(11) |
EP 0 524 127 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
03.02.1993 Bulletin 1993/05 |
| (43) |
Date of publication A2: |
|
20.01.1993 Bulletin 1993/03 |
| (22) |
Date of filing: 12.06.1992 |
|
|
| (84) |
Designated Contracting States: |
|
ES PT |
| (30) |
Priority: |
14.06.1991 BR 9102464
|
| (71) |
Applicant: S.A. WHITE MARTINS |
|
Rio de Janeiro (BR) |
|
| (72) |
Inventors: |
|
- Colodette, Jorge Luiz
Vicosa,&Minas Gerais (BR)
- Santos de Campos, Ana Sabina
Sao Paulo (BR)
|
| (74) |
Representative: Elzaburu Marquez, Alberto et al |
|
Sres. Elzaburu
Industrial Property Attorneys
Miguel Angel, 21
28010 Madrid
28010 Madrid (ES) |
|
| |
|
| (54) |
Improvements in a process for delignifying lignocellulosic pulp by means of oxygen |
(57) The present invention refers to an improvement for delignifying a lignocellulosic
pulp by means of oxygen wherein ethanol is used as an additive and the process is
carried out at high temperature thereby obtaining a higher reduction of lignin content
of the lignocellulosic pulp, that is, a higher reduction of the Kappa Number in comparison
with conventional processes without, however, prejudicing the pulp quality. The use
of the present invention provides a pulp which, when subjected to subsequent bleaching
sequences, will require a lower amount of chloro compounds in order to achieve the
desired whiteness and will also exhibit a high viscosity thus rendering a product
with good resistance properties.