Synergistic effects on cellulose and lignite co-pyrolysis and co-liquefaction

The synergistic effects of lignite and cellulose co-pyrolysis and co-liquefaction were investigated. The optimal liquid fuel yield of co-pyrolysis was 34.72% at a reaction temperature of 550 °C, with a holding time of 30 min, whereas that of co-liquefaction was 39.26% at a reaction temperature of 340 °C, with a holding time of 30 min, an ethanol content of 60% in sub-/supercritical ethanol-water, and a liquid-material ratio of 10:1 (ml/g). Liquid fuel obtained under the best conditions was performed using Fourier transform infrared (FTIR) spectroscopy and gas chromatograph-mass spectrometer (GC-MS). The results of liquid fuel characterization showed that a synergy in co-pyrolysis and co-liquefaction, and the synergy of co-liquefaction was better than that of co-pyrolysis. The reaction mechanism revealed that the presence of the electron-supplying groups generated from cellulose cracking and ethanol reduced the bond energy in the macromolecular structure of lignite and promoted the thermal conversion of lignite.