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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.

The yellowish color of High Yield Pulp (HYP) gives some psychological obstacles and limits its application in some paper grades. Dyes are widely used in the papermaking process to shade the yellowish color of the paper products. We proposed to add dyes into the HYP manufacturing process to minimize the yellowish hue. In this work, we substituted the dye-added HYP (dyes added in the HYP manufacturing process) for hardwood kraft pulp in the production of fine paper grades, and compared the results from those by adding dyes into the papermaking wet end. A higher dye effectiveness was obtained when we used the dye-added HYP. Also, the dye-added HYP gave more effective performance of Precipitated Calcium Carbonate (PCC) fillers and Optical Brightening Agents (OBA) in terms of CIE whiteness and b*. In addition, the dye-added HYP showed less negative effect on brightness and better compatibility with other dyes. The underlying mechanism for the above experimental observation was proposed.