Turning hardwood dissolving pulp polysaccharide residual material into barrier packaging.

Birch chips were subjected to pilot-scale pre-hydrolysis under various sets of conditions to mimic a pre-hydrolysis step in a dissolving pulp process. The process generates residual process liquor, a wood hydrolysate, and the treated chips may be directly utilized in a dissolving process. The wood hydrolysates were rich in xylan and utilized in the production of fully renewable films that provide very good oxygen barrier function and mechanical integrity also at high relative humidity.

Prehydrolysis in softwood pulping produces a valuable biorefinery fraction for material utilization.

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.

Design of renewable hydrogel release systems from fiberboard mill wastewater.

A new route for the design of renewable hydrogels is presented. The soluble waste from masonite production was isolated, fractionized, and upgraded. The resulting hemicellulose rich fraction was alkenyl-functionalized and used in the preparation of covalently cross-linked hydrogels capable of sustained release of incorporated agents.

Isolation and characterization of water-soluble hemicelluloses from flax shive.

Partially depolymerized, water-soluble hemicelluloses were solubilized from flax shive employing hydrothermal microwave treatment and thereafter subjected to ion-exchange chromatography, enzymatic purification and/or size-exclusion chromatography (SEC). The oligo- and polysaccharide fractions thus obtained were characterized with respect to molar mass, molar mass distribution, degree of polymerization (DP) and degree of substitution with acetyl moieties (DSAc) by employing SEC in combination with MALDI-TOF mass spectrometry. The major portion of the water-soluble flax hemicellulose consisted of an O-acetyl-4-O-methylglucuronoxylan exhibiting a DPp value (i.

Isolation and characterization of O-acetylated glucomannans from aspen and birch wood.

O-acetylated glucomannans were isolated from aspen and birch wood employing two different procedures and thereafter subjected to carbohydrate analysis by NMR spectroscopy and MALDI mass spectrometry. In one of the isolation procedures, acetone-extracted aspen or birch wood meal was extracted with dimethyl sulfoxide and then with hot water. Fractionation of the hemicellulose-containing extracts by size-exclusion chromatography was subsequently performed.

Chemical compositions of hardwood and softwood pulps employing photoacoustic Fourier transform infrared spectroscopy in combination with partial least-squares analysis.

In the present study, hardwood and softwood pulps were characterized by employing Fourier transform infrared photoacoustic spectroscopy (FT-IR-PAS). The pulp samples examined originated from Swedish sulfite and kraft pulp mills, which utilize different cooking processes and modern bleaching technologies. Partial least-squares (PLS) analysis was used to correlate the spectral data obtained with the kappa (K) numbers and carbohydrate compositions of the pulp samples determined by enzymatic hydrolysis and subsequent capillary zone electrophoresis.

Characterization of water-soluble hemicelluloses from spruce and aspen employing SEC/MALDI mass spectroscopy.

Partly depolymerized hemicelluloses isolated from wood chips of spruce and aspen employing microwave treatment were resolved using size-exclusion chromatography (SEC) into oligo- and polysaccharide fractions containing components with a narrow range of sizes, as determined by MALDI mass spectroscopy. The degree of substitution with acetyl moieties (DS) was also calculated on the basis of the MALDI-MS spectra obtained prior to and following deacetylation. For spruce hemicelluloses, the low molecular mass fraction contained small arabino-4-O-methylglucuronoxylan oligosaccharides, with DP values ranging from 4 to approximately 20, separated primarily on the basis of their charge density.

Characterization of O-acetyl-(4-O-methylglucurono)xylan isolated from birch and beech.

The structures of water-soluble birch and beech xylans, extracted from holocellulose using dimethyl sulfoxide, were determined employing 1H and 13C NMR spectroscopy together with chemical analysis. These polysaccharides were found to be O-acetyl-(4-O-methylglucurono)xylans containing one 4-O-methylglucuronic acid substituent for approximately every 15 D-xylose residues. The average degree of acetylation of the xylose residues in these polymers was 0.