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Journal articles
Resource efficiency in deinked pulp production â?¢ a review, TAPPI JOURNAL November 2014
Resource efficiency in deinked pulp production • a review, TAPPI JOURNAL November 2014
Journal articles
Beyond Kraft? Is kraft pulping as good as it gets?
Guest Editorial: Beyond kraft? Is kraft pulping as good as it gets?, TAPPI JOURNAL October 2014
Journal articles
Introduction to the Agenda 2020 Next Generation Chemical Pulping Subgroup
Introduction to the Agenda 2020 Next Generation Chemical Pulping Subgroup, TAPPI JOURNAL October 2014
Journal articles
Anthraquinone-a review of the rise and fall of a pulping catalyst
Anthraquinone-a review of the rise and fall of a pulping catalyst, TAPPI JOURNAL October 2014
Journal articles
Enhancing yield through high-kappa pulping
Enhancing yield through high?kappa pulping, TAPPI JOURNAL October 2014
Journal articles
A new sensor and a novel control concept for optimized fiber line operation
A new sensor and a novel control concept for optimized fiber line operation, TAPPI JOURNAL October 2014
Journal articles
Upsets in papermaking ash control: various dead-time compens
Upsets in papermaking ash control: various dead-time compensators, TAPPI JOURNAL, October 2006
Journal articles
Effects of calcium on peroxide bleaching and washing of ther
Effects of calcium on peroxide bleaching and washing of thermomechanical pulp, TAPPI JOURNAL, October 2006
Journal articles
Magazine articles
Kraft pulp bleaching with a P-stage catalyzed by both bicarbonate and TAED, TAPPI Journal July 2019
ABSTRACT: Peroxide bleaching of softwood and hardwood (eucalypt) kraft pulps was performed in solutions of sodium bicarbonate (NaHCO3), sodium carbonate (Na2CO3), and sodium hydroxide (NaOH). The conventional P stage (hydrogen peroxide + sodium hydroxide; H2O2 + NaOH) was the most effective brightening system without an additional activator. However, peroxide activation by bicarbonate anion (HCO3•) was obvious in all cases where NaHCO3 or Na2CO3 was used. When N,N,N’,N’-tetraacetylethylenediamine (TAED) was added to the bleaching sys-tem, Na2CO3 as the alkali source afforded equal or slightly higher bleached brightness compared to NaOH usage for both the softwood and hardwood pulps. This outcome is attributed to simultaneous peroxide activation by HCO3• and TAED. When applied to the eucalypt pulp, the H2O2/Na2CO3/TAED bleaching system also decreased the bright-ness loss due to thermal reversion.
Journal articles
Magazine articles
Fundamental molecular characterization and comparison of the O, D0, and E stage effluents from hardwood pulp bleaching, TAPPI Journal 2019
ABSTRACT: The present study characterized effluents from the O, D0, and E stages using nuclear magnetic reso-nance (NMR) and gel permeation chromatography (GPC) techniques to better understand the chemical nature of the dissolved organics formed from the bleaching of a high-yield hardwood kraft pulp. Understanding the structures and molecular weight distribution of these organics is the first step in developing methods to mitigate these contam-inates in the discharged effluents. The results indicated that the molecular weight distribution (MWD) of the dis-solved organics from oxygen delignification effluent is broader than those from D0 and E stage effluents. In addition, the O stage filtrate contained considerable amounts of lignin and xylan fragments, which showed its efficiency in removing such materials. The effluent from the D0 stage contained a lower amount of high molecular weight frag-ments and a higher amount of low molecular weight fragments versus the O-stage filtrate. Aromatic structures were nearly absent in the D0 stage filtrate, but the degraded organic material, presumably from oxidized lignin, contained olefinic (C=C) and carbonyl (C=O) functional groups. Furthermore, higher molecular weight fragments were detected in the E-stage effluent, presumably due to the extensive solubilization and removal of the oxidized lignin generated from the D0 pulp.