title: Reaction kinetics of hydrothermal carbonization of loblolly pine.
abstract: Hydrothermal carbonization (HTC) is a pretreatment process to convert diverse feedstocks to homogeneous energy-dense solid fuels. Understanding of reaction kinetics is necessary for reactor design and optimization. In this study, the reaction kinetics and effects of particle size on HTC were investigated. Experiments were conducted in a novel two-chamber reactor maintaining isothermal conditions for 15s to 30 min reaction times. Loblolly pine was treated at 200, 230, and 260°C. During the first few minutes of reaction, the solid-product mass yield decreases rapidly while the calorific value increases rapidly. A simple reaction mechanism is proposed and validated, in which both hemicellulose and cellulose degrade in parallel first-order reactions. Activation energy of hemicellulose and cellulose degradation were determined to be 30 and 73 kJ/mol, respectively. For short HTC times, both reaction and diffusion effects were observed.
authors: Department of Chemical & Materials Engineering, University of Nevada, Reno, 1664 N. Virginia St., MS0170, Reno, NV 89557, USA.
authors: M Toufiq
authors: MT
authors: Reza
authors: Wei
authors: W
authors: Yan
authors: M Helal
authors: MH
authors: Uddin
authors: Joan G
authors: JG
authors: Lynam
authors: S Kent
authors: SK
authors: Hoekman
authors: Charles J
authors: CJ
authors: Coronella
authors: Victor R
authors: VR
authors: Vásquez
mesh_terms: D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D002244:Carbon / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism; D055119:Elastic Modulus / Q000187:drug effects; D007700:Kinetics; D010316:Particle Size; D041603:Pinus taeda / Q000187:drug effects*; D011134:Polysaccharides / Q000378:metabolism; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000494:pharmacology*
chemical_list: D011134:Polysaccharides; D014867:Water; D002244:Carbon; C007916:hemicellulose; D002482:Cellulose