Co-liquefaction of Shengli lignite and Salix psammophila in a sub/super-critical water-ethanol system

The co-liquefaction of Shengli lignite and Salix psammophila was used to produce the bio-oil with sub/super-critical water-ethanol as the reaction medium in a WHF-0.1 stainless steel autoclave. The effects of experimental conditions including reaction temperature, holding time, the ratio of S. lignite to S. psammophila, and addition of catalyst were investigated. NaOH is most beneficial to co-liquefaction of S. lignite and S. psammophila. The characteristics of bio-oil and solid residue under the best conditions were determined, and the chemical compositional analysis of bio-oil was done using Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) were used to characterize the solid residue after the liquefaction. The melting degree of S. lignite in co-liquefaction residue was deeper than that in L-residue, which showed there is a synergic effect between S. lignite and S. psammophila in co-liquefaction.