Improvement of Furfural Production from Concentrated PreHydrolysis Liquor (PHL) of a Kraft-Based Hardwood Dissolving Pulp Production Process

Hemicelluloses present in the prehydrolysis liquor (PHL) of the hardwood kraft-based dissolving pulp production process can be utilized in the production of furfural, which is an important renewable, non-petroleum-based platform chemical. A lower furfural yield was observed from the concentrated sugars in PHL in acetic-acid-catalyzed systems. The reaction rate of sugar consumption and furfural destruction in PHL was higher than those of model xylan and xylose systems, which may be due to the side-reactions of lignin with sugars and carbonization of oligomeric sugars. In order to minimize these side-reactions, a steam-stripping method of generated furfural was adopted. The results showed that the method was effective in increasing the furfural yield (41.5%) from the concentrated PHL.