Title:
A Set of Physical and Chemical Properties for Biochar Characterization in Terms of Soil Application
Author(s):
Dieguez-Alonso, A., Garcia-Rueda, A., Anca-Couce, A., Zobel, N., Behrendt, F.
Document(s):
Paper
Poster
Abstract:
Several chemical and physical properties of biochars are analyzed in this work with the objective of drawing some relations, applicable to different biomasses, which allow the relation between production parameters, biochar properties and soil application. It has been observed that, independently of the material, a linear behavior is followed by the H/C and O/C molar ratios with respect to the volatiles content. That may allow the establishment of parameters for estimating the biochar stability in soil based on the volatiles content. The pH value of biochars may be related to the amount of oxygen-containing functional groups on the char surface. From these groups, acidic ones decrease with a decrease in the volatiles content. CEC -Cation Exchange Capacity-does not show a significant difference between biochars with different volatiles content. This may be due to the different specific surface area that these biochars present, that is to say, biochars with lower volatiles content have higher surface area. Consequently the CEC may be comparable to the one for chars with much higher surface charge density but with lower specific surface area. The structure of the biochar seems to be mainly dominated by microporosity, according to the shape of the adsorption isotherms. However, applying the BJH method for pore size distribution, the average pore radius is around 15 Å, which corresponds approximately with 3 nm average pore size, in the border between microporosity and mesoporosity.
Keywords:
pyrolysis, biochar, physical and chemical properties
Topic:
R&D on Processes for Solid, Liquid and Gaseous Fuels from Biomass
Subtopic:
Advanced solid biofuels
Event:
21st European Biomass Conference and Exhibition
Session:
3CV.1.30
Pages:
1473 - 1477
ISBN:
978-88-89407-53-0
Paper DOI:
10.5071/21stEUBCE2013-3CV.1.30
Price:
FREE
