The Impact of Process Technology and Bleaching Sequences on the Composition of Pulp Extractives and Pulp Market Quality, TAPPICon26

A recent trend in the pulp market has been to replace talc in pitch control processes.1 However, characterizing extractives that give rise to pitch, while identifying the most appropriate pulp treatment proves challenging. Pitch contamination and deposits generated throughout the manufacturing process can degrade final pulp for market use; with several factors like the region of origin, species of wood, bleaching sequences, and process technologies impacting market pulp quality. Using wood chips from a single source species (like eucalyptus), this study aims to isolate and characterize extractives from wood chips, brown pulp, bleached pulp, and final pulp corresponding to contaminants found in dried final pulp sheets. Two manufacturing mills in Brazil, one each from the southern and midwestern regions, with different process technologies and bleaching sequences were studied. Deposits were collected from each location, with extractives processed using dichloromethane (DCM) as a solvent. Analytical techniques including Fourier Transform Infrared (FTIR) Spectroscopy, Pyrolysis-Gas Chromatography/Mass Spectrometry (PY-GC/MS) and Energy-Dispersive X-ray Spectroscopy (EDS) were employed to determine chemical profiles and identify contamination sources. As a result, the lipophilic extractives found transformed throughout the kraft pulp and bleaching sequences, contributing to the formation of dirtiness (defects) found in dried final pulp sheets.

TAPPI conference proceedings and presentations, technical papers, and publication articles provide technical and management data and solutions on topics covering the Pulp, Paper, Tissue, Corrugated Packaging, Flexible Packaging, Nanotechnology and Converting Industries.

Simply select the quantity, add to your cart and your conference paper, presentation or article will be available for immediate download.