Bleaching,brightness stability and chemical characteristics of Eucalyptus grandis-bio-TMP pulps prepared in a biopulping pilot plant

摘要

Biopulping is a technology that can be applied advantageously to mechanical pulping.It presents benefits such as the creation of stronger pulp,as well as energy savings.Unfortunately,biomechanical pulps are darker than conventional TMP pulps.In this work,E.grandis wood was biotreated in a 45-ton biopulping pilot plant and used to produce bio-TMP pulps.Brightness values for unbleached and peroxide bleached pulps were 44% and 70% ISO for these bio-TMP pulps,compared with 60% and 72% ISO for control-TMP produced from untreated wood,respectively.Bleached bio-TMP was more stable to thermal-reversion than the control,while the stability to photo-reversion was similar in both pulps.Milled wood lignins (MWL)were extracted from,studied samples and characterized by gel permeation chromatogra-phy and spectroscopicmethods.