Comparison of pyrolyzed lignin before and after milled wood lignin purification of Norway spruce with increasing steam explosion

Abstract

Increasing energy and chemical needs have to be covered by renewable resources, such as biomass, in the near future. Steam explosion is a green pretreatment for utilizing biomass, but it produces a by-product, pseudo-lignin. By comparing milled wood lignin purified and unpurified samples after steam explosion with pyrolysis–GC–MS, the components of pseudo-lignin should be evident. 2D NMR HSQC was also conducted on the purified samples, in addition to compositional analysis after steam explosion. After steam explosion, there is about 6 wt% of pseudo-lignin, and the pyrolysis shows an increase in diol benzenes and furan components in the unpurified samples, which is associated with pseudo-lignin.