Biomorphic activated porous carbons with complex microstructures from
lignocellulosic residues
MICROPOROUS AND MESOPOROUS MATERIALS, 107 (3):
276-285 (2008)DOI: 10.1016/j.micromeso.2007.03.020
Abstract
Transformation of coir fibers, coir pith and coconut shell endocarp
microstructures is described for the formation of activated carbons. The
carbonization/activation process was carried out using ZnCl2 as
activating agent at 800 degrees C under CO2 atmosphere. The
carbonization/activation process was evaluated by TGA/DTG measurements
which evidenced an increase in the initial decomposition temperature
along with increase in the carbon amount as an effect from ZnCl2. A
detailed morphological analysis based on scanning electron microscopy
with EDX analysis allowed the first description of the anisotropic
cellular microstructure of these plant tissues and also evidenced the
morphology transformation in all samples. From X-ray microtomography
(micro-CT) images a random distribution of large channels was revealed
for zinc containing samples (fibers and endocarp), as a result of
contrast improvement in comparison to unmodified samples. Raman spectra
of carbon samples were measured as a complementary microstructural
evaluation on the basis of spectral deconvolution techniques, indicating
that the size of graphitic crystallites as well as the size of clusters
of imperfect Graphene layers depends on the type of carbon precursor.
(C) 2007 Elsevier Inc. All rights reserved.