(600ci) Furfural Production From Microwave Catalytic Torrefaction of Douglas Fir Sawdust Pellets

Abstract: Furfural is a useful solvent and important intermediate chemical for biofuel production. Literatures reported that pyrolysis of biomass treated by metal chlorides had selectivity on chemicals such as furans and levoglucosans and simplified the composition of bio-oils. However, there are few reports for the effects of metal chlorides on biomass torrefaction which is conducted at the low temperature range from 200 to 300 °C in the absence of oxygen.  Therefore, the focus of this research was to investigate the effects of MgCl₂ loading and reaction conditions on the furfural production by microwave torrefaction of Douglas fir sawdust pellets. The yields of bio-oil and torrefaction gases ranged from 21.73 to 37.04 % and 10.49 to 27.66 % respectively were increased with the increase of MgCl₂ loading and reaction temperature and time while the torrefied biomass yields were decreased. Three models were developed to predict the products yields.  The GC/MS analysis showed that the concentration of furfural in the torrefaction bio-oil was increased with the increase of MgCl₂ loading; and the highest concentration of furfural obtained up to 70 area% was observed at high metal chloride loadings. These results indicate that the MgCl₂ had high selectivity for furfural production in torrefaction process. The torrefaction gases analysis showed that high value chemicals such as carbon monoxide, methane, and propane were produced in high concentration.