Mill Designed Bio bleaching Technologies
Abstract
A key finding of this research program was that Laccase Mediator Systems (LMS) treatments on high-kappa kraft could be successfully accomplished providing substantial delignification (i.e., > 50%) without detrimental impact on viscosity and significantly improved yield properties. The efficiency of the LMS was evident since most of the lignin from the pulp was removed in less than one hour at 45 degrees C. Of the mediators investigated, violuric acid was the most effective vis-a-vis delignification. A comparative study between oxygen delignification and violuric acid revealed that under relatively mild conditions, a single or a double LMS{sub VA} treatment is comparable to a single or a double O stage. Of great notability was the retention of end viscosity of LMS{sub VA} treated pulps with respect to the end viscosity of oxygen treated pulps. These pulps could then be bleached to full brightness values employing conventional ECF bleaching technologies and the final pulp physical properties were equal and/or better than those bleached in a conventional ECF manner employing an aggressively O or OO stage initially. Spectral analyses of residual lignins isolated after LMS treated high-kappa kraft pulps revealed that similar to HBT, VA and NHA preferentially attack phenolic lignin moieties. In addition,more »
- Authors:
- Publication Date:
- Research Org.:
- Golden Field Office, Golden, CO (US)
- Sponsoring Org.:
- USDOE Office of Energy Efficiency and Renewable Energy (EE) (US)
- OSTI Identifier:
- 828216
- Report Number(s):
- DE-FC36-99GO10374
TRN: US200428%%1042
- DOE Contract Number:
- FC36-99GO10374
- Resource Type:
- Technical Report
- Resource Relation:
- Other Information: PBD: 30 Jan 2004
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 09 BIOMASS FUELS; BLEACHING; BRIGHTNESS; CARBOXYLIC ACIDS; CHEMISTRY; DELIGNIFICATION; FUNCTIONALS; KNOWLEDGE BASE; LIGNIN; OXIDATION; OXYGEN; PHYSICAL PROPERTIES; REDOX POTENTIAL; RESEARCH PROGRAMS; RETENTION; VISCOSITY
Citation Formats
Institute of Paper Science Technology. Mill Designed Bio bleaching Technologies. United States: N. p., 2004.
Web. doi:10.2172/828216.
Institute of Paper Science Technology. Mill Designed Bio bleaching Technologies. United States. https://doi.org/10.2172/828216
Institute of Paper Science Technology. 2004.
"Mill Designed Bio bleaching Technologies". United States. https://doi.org/10.2172/828216. https://www.osti.gov/servlets/purl/828216.
@article{osti_828216,
title = {Mill Designed Bio bleaching Technologies},
author = {Institute of Paper Science Technology},
abstractNote = {A key finding of this research program was that Laccase Mediator Systems (LMS) treatments on high-kappa kraft could be successfully accomplished providing substantial delignification (i.e., > 50%) without detrimental impact on viscosity and significantly improved yield properties. The efficiency of the LMS was evident since most of the lignin from the pulp was removed in less than one hour at 45 degrees C. Of the mediators investigated, violuric acid was the most effective vis-a-vis delignification. A comparative study between oxygen delignification and violuric acid revealed that under relatively mild conditions, a single or a double LMS{sub VA} treatment is comparable to a single or a double O stage. Of great notability was the retention of end viscosity of LMS{sub VA} treated pulps with respect to the end viscosity of oxygen treated pulps. These pulps could then be bleached to full brightness values employing conventional ECF bleaching technologies and the final pulp physical properties were equal and/or better than those bleached in a conventional ECF manner employing an aggressively O or OO stage initially. Spectral analyses of residual lignins isolated after LMS treated high-kappa kraft pulps revealed that similar to HBT, VA and NHA preferentially attack phenolic lignin moieties. In addition, a substantial decrease in aliphatic hydroxyl groups was also noted, suggesting side chain oxidation. In all cases, an increase in carboxylic acid was observed. Of notable importance was the different selectivity of NHA, VA and HBT towards lignin functional groups, despite the common N-OH moiety. C-5 condensed phenolic lignin groups were overall resistant to an LMS{sub NHA, HBT} treatments but to a lesser extent to an LMS{sub VA}. The inactiveness of these condensed lignin moieties was not observed when low-kappa kraft pulps were biobleached, suggesting that the LMS chemistry is influenced by the extent of delignification. We have also demonstrated that the current generation of laccase has a broad spectrum of operating parameters. Nonetheless, the development of future genetically engineered laccases with enhanced temperature, pH and redox potentials will dramatically improve the overall process. A second challenge for LMS bleaching technologies is the need to develop effective, catalytic mediators. From the literature we already know this is feasible since ABTS and some inorganic mediators are catalytic. Unfortunately, the mediators that exhibit catalytic properties do not exhibit significant delignification properties and this is a challenge for future research studies. Potential short-term mill application of laccase has been recently reported by Felby132 and Chandra133 as they have demonstrated that the physical properties of linerboard can be improved when exposed to laccase without a chemical mediator. In addition, xxx has shown that the addition of laccase to the whitewater of the paper machine has several benefits for the removal of colloidal materials. Finally, this research program has presented important features on the delignification chemistry of LMS{sub NHA} and LMS{sub VA} that, in the opinion of the author, are momentous contributions to the overall LMS chemistry/biochemistry knowledge base which will continue to have future benefits.},
doi = {10.2172/828216},
url = {https://www.osti.gov/biblio/828216},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri Jan 30 00:00:00 EST 2004},
month = {Fri Jan 30 00:00:00 EST 2004}
}