Catalytic depolymerization of a lignin-rich corncob residue into aromatics in supercritical ethanol over an alumina-supported nimo alloy catalyst

Research output: Contribution to journalArticleScientificpeer-review

Researchers

  • Yunfei Bai
  • Kai Cui

  • Yushuai Sang
  • Kai Wu
  • Fei Yan
  • Fuhang Mai
  • Zewei Ma
  • Zhe Wen
  • Hong Chen
  • Mengmeng Chen
  • Yongdan Li

Research units

  • Tianjin University
  • Collaborative Innovation Center of Chemical Science and Engineering Tianjin
  • Tianjin University

Abstract

A one-pot process for the depolymerization of lignin-rich corncob residue (LRCR) is investigated in supercritical ethanol over an alumina-supported NiMo (NiMo/Al) alloy catalyst. The LRCR, as a major byproduct in the corncob enzymatic hydrolysis process, was completely liquefied and effectively transformed into aromatic compounds without the formation of tar or char under optimal reaction conditions. The reaction temperature, time, solvent, and initial hydrogen pressure have significant effects on the depolymerization of LRCR. The highest overall aromatic yield of 255.4 mg/g of LRCR with 57.9 wt % alkylphenols (e.g., 4-ethylphenol, 2,5-diethylphenol, and 2,6-diisopropylphenol) was achieved with an initial 27.6 bar (gauge) of hydrogen in supercritical ethanol at 320 °C for 7.5 h. The depolymerization of LRCR is also examined over Ni/γ-Al2O3, Mo/γ-Al2O3, and the physical mixture of these two catalysts. The NiMo/Al alloy catalyst exhibits much higher activity than that of other catalysts, and a synergistic effect between Ni and Mo active species is proposed. Furthermore, X-ray powder diffraction results show that the Mo1.24Ni0.76 alloy is expected to be an important active species for the depolymerization reaction.

Details

Original languageEnglish
Pages (from-to)8657-8665
Number of pages9
JournalEnergy and Fuels
Volume33
Issue number9
Publication statusPublished - 19 Sep 2019
MoE publication typeA1 Journal article-refereed

ID: 37758129