Comparison of pulp species in IONCELL-P: selective hemicellulose extraction method with ionic liquids

Holzforschung ◽  
2016 ◽  
Vol 70 (4) ◽  
pp. 291-296 ◽  
Author(s):  
Annariikka Roselli ◽  
Sari Asikainen ◽  
Agnes Stepan ◽  
Alireza Monshizadeh ◽  
Niklas von Weymarn ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Kraft Pulp ◽  
Polymer Degradation ◽  
Solvent System ◽  
Fiber Structure ◽  
Yield Losses ◽  
Optimum Conditions ◽  
Pulp Viscosity ◽  
Birch Kraft Pulp ◽  
Xylan Content

Abstract In our recent studies, it was demonstrated that the IONCELL-P process selectively dissolves hemicelluloses from bleached birch kraft pulp in a mixture of 1-ethyl-3-methylimidazolium acetate ([emim][OAc]) and water as a solvent system. The IONCELL-P method refines paper-grade pulp to dissolving pulp with <5% hemicelluloses and allows isolation of polymeric xylan without yield losses or polymer degradation. This paper is a comparative study where paper-grade pine, birch, and eucalyptus pulps are subjected to the IONCELL-P process with two [emim]-based ionic liquids (ILs), i.e. [emim]acetate and [emim]dimethylphosphate. Also, the effect of an endoglucanase pretreatment was investigated to check whether 1) the pulp viscosity could be adjusted for the following process steps before the hemicellulose extraction and 2) the decreasing pulp viscosity would open the fiber structure and thus enhance the extraction. Under optimum conditions, the birch xylan content could be reduced from 25.4% down to 1.3% and for eucalyptus from 16.6% to 2.4%. Pine pulp xylan and glucomannan were decreased from 8.1% and 7.1% to 0.9% and 2.2%, respectively. The residual hemicellulose contents of the pine pulp could be further decreased with a hemicellulase pretreatment. The selectivity of the dissolution towards hemicelluloses was better for hardwoods. Adjusting the pulp viscosity by endoglucanase prior to the IONCELL-P process reduced the selectivity as short-chain cellulose molecules were extracted along with the hemicelluloses.

Effect of reduced pulp xylan content on wet end chemistry and paper properties — a pilot scale study

TAPPI Journal ◽  
2014 ◽  
Vol 13 (2) ◽  
pp. 29-37 ◽  
Author(s):  
KATJA LYYTIKÄINEN ◽  
ESA SAUKKONEN ◽  
MARKKU VÄISÄNEN ◽  
JUSSI TIMONEN ◽  
KAJ BACKFOLK
Keyword(s):  
Kraft Pulp ◽  
Scale Up ◽  
Pilot Scale ◽  
Partial Replacement ◽  
Paper Machine ◽  
Charge Balance ◽  
Paper Properties ◽  
Birch Kraft Pulp ◽  
Positive Effect ◽  
Xylan Content

In this scale-up study, we examined the effects of using varying amounts of fibers with reduced xylan content in paper. Bleached birch kraft pulp was partially or fully replaced by alkali-extracted pulp, and the effects of this replacement on the wet end chemistry of the paper machine and the resulting paper properties were determined. Our results show that paper properties can be maintained or improved when optimizing the partial replacement of bleached birch kraft pulp with alkali-extracted pulp. The incorporation of alkali-extracted pulp in paper machine stock had a positive effect on first pass retention and retention of chemicals. However, careful optimization of chemical dosages is required because of the altered charge balance in the wet end.

Prebleaching of eucalypt kraft pulp with OP stages: Effect of an acid pretreatment or chelation step

TAPPI Journal ◽  
2012 ◽  
Vol 11 (6) ◽  
pp. 31-38
Author(s):  
TATIANA M. PÓVOAS ◽  
DINA A.G. ANGÉLICO ◽  
ANA P.V. EGAS ◽  
PEDRO E.G. LOUREIRO ◽  
LICÍNIO M. GANDO-FERREIRA ◽  
...  
Keyword(s):  
Eucalyptus Globulus ◽  
Comparative Evaluation ◽  
Kraft Pulp ◽  
Kraft Pulps ◽  
Acid Pretreatment ◽  
High Brightness ◽  
Pulp Viscosity ◽  
Brightness Reversion

We conducted a comparative evaluation of different treatments for the bleaching of eucalypt kraft pulps beginning with OP stages. The treatments tested were (1) an acid chelation stage with DTPA (OQP sequence); (2) a hot acid stage (AOP sequence); and (3) a chelant addition into the alkaline oxygen stage ((OQ)P and A(OQ)P sequences). The latter strategy was also studied for environmental reasons, as it contributes to the closure of the filtrate cycle. The OQP sequence leads to the highest brightness gain and pulp viscosity and the lowest peroxide consumption caused by an efficient metals control. Considering that the low biodegradability of the chelant is a problem, the A(OQ)P sequence is an interesting option because it leads to reduced peroxide consumption (excluding OQP) while still reaching high brightness values and similar brightness reversion to OQP prebleaching, with only a viscosity loss of 160 dm3/kg. Therefore, a hot acid stage could be considered when a separate acid Q stage is absent in a prebleaching sequence of Eucalyptus globulus kraft pulps involving OP stages.

scholarly journals Cellulose Nanofibril (CNF) Films and Xylan from Hot Water Extracted Birch Kraft Pulps

2019 ◽  
Vol 9 (16) ◽  
pp. 3436 ◽  
Author(s):  
Marc Borrega ◽  
Hannes Orelma
Keyword(s):  
Food Packaging ◽  
Kraft Pulp ◽  
Barrier Properties ◽  
Hot Water ◽  
Kraft Pulps ◽  
Cellulose Nanofibril ◽  
Vapour Permeability ◽  
Transparent Films ◽  
Cnf Films ◽  
Birch Kraft Pulp

The effects of xylan extraction from birch kraft pulp on the manufacture and properties of cellulose nanofibril (CNF) films were here investigated. Hot water extractions of bleached and unbleached kraft pulps were performed in a flow-through system to remove and recover the xylan. After the extraction, the pulps were oxidized with 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO) and fibrillated in a high-pressure microfluidizer. Compared to CNF from bleached kraft pulp, the CNF dispersions obtained from water-extracted pulps were less viscous and generally contained a higher amount of microfiber fragments, although smaller in size. In all cases, however, smooth and highly transparent films were produced from the CNF dispersions after the addition of sorbitol as plasticizer. The CNF films made from water-extracted pulps showed a lower tensile strength and ductility, probably due to their lower xylan content, but the stiffness was only reduced by the presence of lignin. Interestingly, the CNF films from water-extracted bleached pulps were less hydrophilic, and their water vapour permeability was reduced up to 25%. Therefore, hot water extraction of bleached birch kraft pulp could be used to produce CNF films with improved barrier properties for food packaging, while obtaining a high-purity xylan stream for other high-value applications.

Mechanoradical formation and its effects on birch kraft pulp during the preparation of nanofibrillated cellulose with Masuko refining

Holzforschung ◽  
2012 ◽  
Vol 66 (4) ◽  
Author(s):  
Iina Solala ◽  
Aleksander Volperts ◽  
Anna Andersone ◽  
Tatiana Dizhbite ◽  
Nina Mironova-Ulmane ◽  
...  
Keyword(s):  
Electron Paramagnetic Resonance Spectroscopy ◽  
Fiber Material ◽  
Nanofibrillated Cellulose ◽  
Resonance Spectroscopy ◽  
Paramagnetic Resonance ◽  
Pulp Viscosity ◽  
Antioxidant Characteristics ◽  
Birch Kraft Pulp ◽  
Recombination Reactions

AbstractMasuko refining of unbleached kraft birch pulp has been noted to result in more thorough fibrillation than the refining of its bleached counterpart. This result is observed through different fractionation behavior of once refined pulps and is further supported by different relative changes in pulp viscosity. The formation of mechanoradicals during refining is observed with electron paramagnetic resonance spectroscopy, and the role of lignin and hemicelluloses [quantified using kappa number determination and UV resonance Raman (UVRR) spectroscopy] in the progress of refining is discussed. Lignin, a known antioxidant, is capable of stabilizing radicals, which could potentially counteract recombination reactions between highly reactive cellulose radicals. On the other hand, lignin’s ability to promote fibrillation could also lie in its amorphous nature and not solely in its antioxidant characteristics. Furthermore, bleaching removes not only lignin but also hemicelluloses, which affects both the charge density and the structure of the fiber material, and this is another likely contributor to the easier fibrillation of lignin-containing pulps.

scholarly journals OPTIMIZATION OF SAMPLE PREPARATION FOR THE DETERMINATION OF HPA'S VISION IN A GEOMETRIC TECHNIQUE USING MOLECULAR FLUORESCENCE

2012 ◽  
Vol 09 (18) ◽  
pp. 65-70
Author(s):  
Andréa Francisca Fernandes BARBOSA ◽  
Dayanne Chianca MOURA ◽  
Fabiana Roberta Gonsalves da Silva HUSSEIN ◽  
Jailson Vieira MELO ◽  
Djalma Ribeiro SILVA
Keyword(s):  
Sample Preparation ◽  
Solvent System ◽  
Optimum Conditions ◽  
23 Factorial Design ◽  
Essential Step ◽  
Analysis Process ◽  
The Matrix ◽  
Molecular Fluorescence ◽  
Geometric Technique

The sample preparation is considered an essential step in the analysis process. The complexity of the matrix and how the compounds are linked is one of the main difficulties in the extraction. Thus a solvent system combined with an extraction method, both need to be effective against such mishaps. In this work we used the 23 factorial design to determine the optimum conditions for sample preparation. The analysis of the samples were performed in a molecular fluorescence spectrophotometer. The factors selected to investigate the influence on the extraction system were: time of use of ultrasound, the type of solvent (hexane or dichloromethane) and ratio solvent / sample (1:1 and 1:3). The best result was obtained with using the dichloromethane in time of 10 min of ultrasound and the ratio solvent / sample 1:3.

Polyoxometalate Delignification of Birch Kraft Pulp and Effect on Residual Lignin

2011 ◽  
Vol 31 (2) ◽  
pp. 121-141 ◽  
Author(s):  
Biljana Bujanovic ◽  
Richard S. Reiner ◽  
Sally A. Ralph ◽  
Rajai H. Atalla
Keyword(s):  
Kraft Pulp ◽  
Residual Lignin ◽  
Birch Kraft Pulp

Surface selective removal of xylan from refined never-dried birch kraft pulp

Cellulose ◽  
2014 ◽  
Vol 21 (5) ◽  
pp. 3677-3690 ◽  
Author(s):  
Esa Saukkonen ◽  
Katja Lyytikäinen ◽  
Pavel Geydt ◽  
Kaj Backfolk
Keyword(s):  
Kraft Pulp ◽  
Selective Removal ◽  
Birch Kraft Pulp

Molecular Dynamics Study of Candida rugosa Lipase in Water, Methanol, and Pyridinium Based Ionic Liquids

2021 ◽  
Vol 874 ◽  
pp. 88-95
Author(s):  
Oktavianus Hendra Cipta ◽  
Anita Alni ◽  
Rukman Hertadi
Keyword(s):  
Molecular Dynamics ◽  
Ionic Liquid ◽  
Ionic Liquids ◽  
Candida Rugosa ◽  
Solvent System ◽  
Dynamics Simulation ◽  
Initial Structure ◽  
Enzymatic Reactions ◽  
Solvent Systems ◽  
To Come

The structure of Candida rugosa lipase can be affected by solvents used in the enzymatic reactions. Using molecular dynamics simulation as a tool to study the Candida rugosa lipase structure, we studied the effect of various solvent systems, such as water, water-methanol, and water-methanol-ionic liquid. These solvent systems have been chosen because lipase is able to function in both aqueous and non-aqueous medium. In this study, pyridinium (Py)-based ionic liquids were selected as co-solvent. The MD simulation was run for 50 nanoseconds for each solvent system at 328 K. In the case of water-methanol-ionic liquids solvent systems, the total number of the ionic liquids added were varied: 222, 444, and 888 molecules. Water was used as the reference solvent system. The structure of Candida rugosa lipase in water-methanol system significantly changed from the initial structure as indicated by the RMSD value, which was about 6.4 Å after 50 ns simulation. This value was relatively higher compared to the other water-methanol solvent system containing ionic liquid as co-solvent, which were 2.43 Å for 4Py-Br, 2.1 Å for 8Py-Br, 3.37 Å for 4Py-BF4 and 3.49 Å for 8Py-BF4 respectively. Further analysis by calculating the root mean square fluctuation (RMSF) of each lipase residue found that the presence of ionic liquids could reduce changes in the enzyme structure. This happened because the anion component of the ionic liquid interacts relatively more strongly with residues on the surface of the protein as compared to methanol, thereby lowering the possibility of methanol to come into contact with the protein.

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