title: Chemical and morphological changes in hydrochars derived from microcrystalline cellulose and investigated by chromatographic, spectroscopic and adsorption techniques.
abstract: Hydrothermal carbonization (HTC) can be used for converting the biomass into a carbon-rich material, whose application as a fuel requires higher heating value, whereas soil amendment needs stable carbon. This work was focused on the characterization of hydrochars derived from microcrystalline cellulose. The chars were investigated using elemental analysis, Brunauer-Emmett-Teller technique, nuclear magnetic resonance spectroscopy, Raman, Fourier transform infrared, and electron spin resonance spectroscopy. Severity in temperature between 230 and 270°C with reaction times between 2 and 10 h only affect the carbon content moderately. The results show that aromatization of HTC chars correlates well with temperature, which was further supported by the increase of organic radicals with decreasing g values at higher temperatures. Based on these results, the energetic use of chars favors mild HTC (T<230°C and t≤6 h), while the soil amendement favors serve conditions (T≥230°C, and t>6 h).
authors.affiliation: Leibniz Institute for Agricultural Engineering Potsdam-Bornim e.V., Max-Eyth-Allee 100, 14469 Potsdam, Germany. Electronic address: mdiakite@atb-potsdam.de.
authors.forename: Mamadou
authors.initials: M
authors.lastname: Diakité
authors.forename: Andrea
authors.initials: A
authors.lastname: Paul
authors.forename: Christian
authors.initials: C
authors.lastname: Jäger
authors.forename: Judith
authors.initials: J
authors.lastname: Pielert
authors.forename: Jan
authors.initials: J
authors.lastname: Mumme
mesh_terms: D000327:Adsorption; D002264:Carboxylic Acids / Q000737:chemistry; D002482:Cellulose / Q000737:chemistry*; D002606:Charcoal / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid; D004578:Electron Spin Resonance Spectroscopy; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D016062:Porosity; D013059:Spectrum Analysis, Raman; D013696:Temperature; D013997:Time Factors; D014732:Vibration
chemical_list: D002264:Carboxylic Acids; C540010:biochar; D002606:Charcoal; D002482:Cellulose; C109691:microcrystalline cellulose
keywords: ATR-FTIR-spectroscopy; Hydrochar; Hydrothermal carbonization; Microcrystalline cellulose; NMR-spectroscopy