Energy & Fuels, Vol.28, No.7, 4260-4266, 2014
Composition Analysis of Organosolv Lignin and Its Catalytic Solvolysis in Supercritical Alcohol
The structural analysis and catalytic solvolysis performance of organosolv lignins from Chinese fir (softwood) and maple (hardwood) were investigated. Fourier transformation infrared spectroscopy (FTIR) analysis revealed that both Chinese fir lignin and maple lignin exhibited a guaiacyl syringyl structure. Chinese fir lignin consisted of guaiacyl units principally, while maple lignin consisted of syringyl units mainly. The ratios of guaiacol-/syringol-type products obtained by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) were 2.53 for Chinese fir lignin and 0.29 for maple lignin, respectively. The catalytic solvolysis degradation was studied in supercritical ethanol/1-butanol at 300 degrees C with Ru/C to produce phenolic compounds. The degradation products of Chinese fir lignin were mainly guaiacol-type products, while the products of maple lignin consisted of both guaiacol- and syringol-type compounds. The yields of most products of maple lignin were much higher than those of Chinese fir lignin. The results show that the organosolv maple lignin is a potential feedstock for producing phenolic products through the solvolytic method.