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A scaled-up prehydrolysis process was elaborated to demonstrate an industrially feasible operation step in a pulping process that generates a valuable side product in addition to the cellulose pulp. The valuable side product is aqueous process liquor, a softwood hydrolysate (SWH) herein produced in 60 L batches, and its components were recovered and utilized as materials. The process parameters were shown to influence the yield, composition, and quality of the obtained hydrolysates. Furthermore, the process conditions were shown to influence the ability of SWHs to form free-standing, foldable films in blends with either microfibrillated cellulose (MFC) or carboxymethyl cellulose (CMC). Films with oxygen permeabilities (OP) as low as 0.35 cm 3 ÎŒm day -1 m -2 kPa -1 at 50% relative humidity, were produced from aqueous solutions providing a viable and green alternative to petroleum-based packaging barriers. The OPs were very low regardless of SWH film composition and upgrading conditions, whereas the films' tensile performance was directly controlled by the ratio of SWH to cocomponent., QC 20120904

QCR 20190205

The development of paper strength properties during chlorine dioxide ECF and alkaline peroxide TCF bleaching of kraft and soda-AQ pulps and the relation to the chemical composition of the fiber surface and inner layers was investigated. Surface and inner fiber wall layer materials were collected by mechanical peeling and analyzed by enzymatic hydrolysis and capillary electrophoretic analysis for carbohydrates and pyrolysis combined with gas chromatography and mass spectrometry for lignin. The surface layers of the fibers revealed greater chemical changes by bleaching operations than did the inner layers. Handsheets were produced and tested for strength. Correlation was found between the tensile index and hemicellulose content of the fiber surface layer., QC 20141205