Effects of Reaction Conditions on Phenol Liquefaction of Beetle-infested Lodgepole Pine Barks

In this study, mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) infested lodgepole pine (Pinus contorta Dougl.) barks were liquefied in phenol using sulfuric acid as the catalyst. Results showed that liquefaction conditions, such as reaction time, reaction temperature, phenol/bark ratio, and catalyst loading had significant effects on the liquefaction yield, free phenol content of the liquefied bark fraction and the properties of the unliquefied bark residues. Higher reaction temperature and prolonged reaction time not only promoted the degradation of the bark components during the liquefaction but also induced recondensation reactions among the degraded bark components. Higher phenol/bark ratio increased the bark liquefaction yield by retarding the recondensation reactions among the degraded bark components. The liquefaction yield, free phenol content in the liquefied bark fraction and residues properties were found to be mostly affected by the catalyst loading, followed by the reaction temperature, reaction time and phenol/bark ratio.