[greenyes] New ways to bleach pulp paper

[Amy Perlmutter <amyperl@no.address>]

I don¹t know anything other than what¹s here; I¹m just passing the abstract
along. The full article is in Green Chemistry (see below)

Amy

  

TITLE Electron Transfer Mediator Systems for Bleaching of Pulp Paper
AUTHOR Rochefort, D.; Leech, D.; Bourbonnais, R.
SOURCE Green Chemistry, January 2004, vol. 6, no. 1, pp. 14-24
ABSTRACT The participation of biological agents in pulp bleaching systems
has received a lot of attention from research teams around the world, driven
by the environmental benefits that biobleaching could bring. Nature showed
us the ability of some of its agents, such as wood-decaying fungi, to
delignify 
and bleach wood and wood pulp. what we need to do is to enhance the
efficiency of such agents to make them cope with the fast pace of our
modern pulp mills. To do so, a profound understanding of the biobleaching
system is required. Our efforts to discover new efficient mediators for
the laccase-mediator system (LMS) brought us to use several techniques
to analyze the reactions involved in mediated enzymatic delignification.
Mostly based on electrochemistry, these techniques are reviewed in this
paper, along with key results,. Cyclic voltammetry was used to characterize
electron transfer rates between each element of the LMS. We found, along
with other authors, that the mediator redox potential has a great influence
on its efficiency. We used bulk electrolysis to simulate the oxidative
action 
of laccase on mediators and model compounds of lignin. Such electrolysis
techniques allowed us to study mediated lignin oxidation outside of normal
laccase working conditions. Finally, an electrolysis-based method for
mediated pulp delignification that we developed, based upon our research
on biobleaching, is presented.