Cellulose was first precursor fibre material used for
production of carbon fibres. It has been in many
application replaced with polyacrylonitrile (PAN) and
isotropic pitch, especially in high modulus applications.
However, cellulose and more precisely viscose (rayon) has
still remained some markets due to beneficial properties
including good thermal stability of resulted fibres and
low price of raw material. Additional attractive feature
is its renewability and bio-based origin.
We have studied use of cellulosic fibres for production
of carbon fibres. Our premise was that nitrogen content
of cellulose carbamate fibres may be beneficial for the
carbonization result. In experimental part we used
wet-spun non-viscose fibres from enzymatically treated
dissolved cellulose, so called BioCellSol cellulose and
nitrogen containing cellulose carbamate. We studied use
of various chemical agents, (NH4)2HPO4, H2SO4, and NH4Cl,
in order to increase low carbon yield, and produced
carbon and activated carbon materials. In order to obtain
better understanding of carbonization of cellulose we
performed reactive molecular dynamics simulations.
In this presentation we review work carried out and
results obtained within this study. In experimental study
we learned for example, that carbon yield obtained with
different impregnation agents (14 -21 %) was
significantly higher than of non-treated reference (10%),
best results obtained with (NH4)2HPO4. Strength of the
obtained fibres was not as good as needed for
load-bearing composite applications since we were not
able to apply sufficient tensioning. However, coherent
activated carbon fibres and nonwovens were obtained and
they could be used e.g. for water purification and
removal of odours from gas flow. Modelling efforts
indicated that carbamation of cellulose is beneficial for
both carbon yield in terms of carbon amount, and carbon
quality in terms of amount carbon rings formed.
This work was carried out in Bio-Based Tailored
Precursors for Advanced Carbons and Applications
(BioPreCarb) project funded by Tekes - the Finnish
Funding Agency for Innovation, VTT Technical Research
Centre of Finland and Tampere University of Technology.
Project was aiming for review possibilities to create
bio-based carbon business in Finland.
|Conference||Annual World Conference on Carbon|
|Abbreviated title||CARBON 2015|
|Period||12/07/15 → 17/07/15|