title: Effect of self-purging pyrolysis on yield of biochar from maize cobs, husks and leaves.
abstract: In this study, biochar was produced from maize residues (cobs, husks, leaves) in a lab-scale pyrolysis reactor without using a purging gas. The physicochemical properties of biomass and biochar were analysed. Box-Behnken design was used to optimise operational conditions for biochar yields. Multivariate correlations of biochar yields were established using reduced quadratic models with R(2)=0.9949, 0.9801 and 0.9876 for cobs, husks and leaves, respectively. Biochar yields were negatively correlated with the temperature, which was significantly influenced by the exothermic reactions during the pyrolysis of maize residues. The heating rate was found to have the least effect on biochar yields. Under optimal conditions, the maximum biochar yields from cobs, husks and leaves were 33.42, 30.69 and 37.91%, respectively. The highest biochar yield from maize leaves was obtained at a temperature of 300°C, a heating rate of 15°C/min and a holding time of 30min.
authors.affiliation: Universität Hohenheim, Institute of Agricultural Engineering (440e), Tropics and Subtropics Group, Stuttgart 70599, Germany. Electronic address: info440e@uni-hohenheim.de.
authors.forename: Kiatkamjon
authors.initials: K
authors.lastname: Intani
authors.affiliation: Universität Hohenheim, Institute of Agricultural Engineering (440e), Tropics and Subtropics Group, Stuttgart 70599, Germany.
authors.forename: Sajid
authors.initials: S
authors.lastname: Latif
authors.affiliation: Universität Hohenheim, Institute of Agricultural Engineering (440e), Tropics and Subtropics Group, Stuttgart 70599, Germany.
authors.forename: A K M Rafayatul
authors.initials: AK
authors.lastname: Kabir
authors.affiliation: Universität Hohenheim, Institute of Agricultural Engineering (440e), Tropics and Subtropics Group, Stuttgart 70599, Germany.
authors.forename: Joachim
authors.initials: J
authors.lastname: Müller
mesh_terms: D018533:Biomass; D019149:Bioreactors; D002606:Charcoal / Q000378:metabolism*; D005740:Gases / Q000378:metabolism; D006358:Hot Temperature; D006868:Hydrolysis; D024301:Plant Bark / Q000378:metabolism; D018515:Plant Leaves / Q000378:metabolism*; D013696:Temperature; D003313:Zea mays / Q000378:metabolism*
chemical_list: D005740:Gases; C540010:biochar; D002606:Charcoal
keywords: Biochar; Maize residues; Response surface methodology; Self-purging; Slow pyrolysis