| Título: | CHARACTERIZATION OF Eucalyptus grandis KRAFT PULPS TREATED WITH PHOSPHONATES IN DIFFERENT STAGES OF TCF BLEACHING |
| Autores: |
Area, Maria Cristina Felissia, Fernando E. Carvalho, M. Graca V. S. Ferreira, Paulo J. Barboza, Olga M. Benoechea, Dora I |
| Fecha: | 2011-02-11 |
| Publicador: | Bioresources |
| Fuente: |
 |
| Tipo: |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion |
| Tema: | Kraft pulp; TCF bleaching; Chelating agent; Phosphonates; Eucalyptus |
| Descripción: | The addition of a phosphonated chelant (DTPMPA) at different points of a TCF bleaching sequence and its effect on pulp properties were studied in this work. An industrial Eucalyptus grandis kraft pulp was submitted to a counter-ion exchange (Ca2+ or Na+ form) and was then bleached using DTPMPA in the washing or in the bleaching stages of two distinct sequences: OOpP and OQOpP (20 pulps). The counter-ion exchange affected fibre length, as well as the handsheets bulk and air permeability (higher for Na+-based pulps) and handsheet tensile strength, brightness, skeletal density, and total porosity based on Hg porosimetry (higher for Ca2+-based pulps). The hydrogen peroxide consumption in Op and P stages achieved the lowest values when the chelant was distributed rather than applied in a separate Q stage. The addition of chelant in the P stage provides pulps with higher ISO brightness (>85%). The chelant effects were always more noticeable in Ca2+-based pulps. |
| Idioma: | Inglés |