Conversion of guaiacol in supercritical water gasification: Detailed effect of feedstock concentration

• Published in: The Journal of supercritical fluids 2018-12, Vol.142, p.32-37
• Main Authors: Changsuwan, Pattraporn, Paksung, Nattacha, Inoue, Shuhei, Inoue, Takahito, Kawai, Yoshifumi, Noguchi, Takashi, Tanigawa, Hiroaki, Matsumura, Yukihiko
• Format: Article
• Language: English
• Subjects: Carbon gasification efficiency (CGE); Char formation; Feedstock concentration; Guaiacol; Supercritical water gasification (SCWG)
• ISSN: 0896-8446; 1872-8162
• DOI: 10.1016/j.supflu.2018.05.024

[Display omitted] •Guaiacol was gasified in supercritical water as a model compound for lignin.•The influences of feedstock concentration on char and H2 yields were investigated.•Tarry material visibly increased for high initial feedstock.•A reaction model successfully reproduced experimental results. The effect of feedstock concentration on the gasification characteristics of guaiacol, a model compound for lignin, in supercritical water was investigated using a laboratory-scale continuous-flow reactor. The reaction temperature, pressure, and residence time used were 600 °C, 25 MPa, and 94 s, respectively. A reaction model was developed and kinetic parameters were determined so that experimental results could be reproduced. The carbon gasification efficiency (CGE) and TOC yield were not affected by the initial concentration of guaiacol. Solid yields increased with feedstock concentration, reflecting an order of reaction greater than one for solid production. A reaction model was developed and the reaction rate constants were determined successfully to reproduce experimental results. The decomposition rate constant was determined as 0.0718 ± 0.0403 /s and was found to be in good agreement with the previous study. The reaction order for the solid production was determined to be 1.25.