A comparative study of enzymatic and Fenton pretreatment applied to a birch kraft pulp used for MFC production in a pilot scale high-pressure homogenizer

Microfibrillated cellulose (MFC) was produced in pilot scale from a bleached birch (Betula verrucosa) kraft pulp that was pretreated with either Fenton’s reagent or with a combined mechanical and enzymatic method used at the Centre Technique du Papier (CTP; Grenoble, France). The change in fiber fibrillation during the homogenization treatment was monitored by analyzing the fiber and the fines content, size fractionation, rheological properties and visualization by light- and scanning electron microscopy (SEM). The Fenton pretreatment resulted in MFC suspensions that contained a high amount of small sized elements. After five passes through the highpressure homogenizer, the amount of particles smaller than 20 μm was 37% for the Fenton pretreated MFC compared to 13% for the enzymatically (endoglucanase) pretreated MFC. Altogether, the Fenton pretreatment enabled preparation of MFC with a higher degree of fibrillation after the same number of passes through the high-pressure homogenizer. Another option is to produce MFC of the same amount of fibrillation as after an enzymatic stage, but at significantly lower energy consumption.

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Functionalisation of Pectin by Ultra High Pressure Homogenisation

Proceedings ◽

10.3390/foods_2020-07752 ◽

2020 ◽

Vol 70 (1) ◽

pp. 50

Author(s):

Milena Zdravkovic ◽

Edward Ebert ◽

Chen Panz ◽

Zoya Okun ◽

Hans-Ulrich Endreß ◽

...

Keyword(s):

High Pressure ◽

Apparent Viscosity ◽

Dynamic Pressure ◽

Gelation Time ◽

Pilot Scale ◽

Dependent Manner ◽

Ultra High Pressure ◽

Beverage Industry ◽

Food And Beverage ◽

High Pressure Homogenizer

Pectin is well-known plant-based hydrocolloid extensively used in food and beverage industry for formation and/or enhancement of product texture and stability. Versatile functionalities of different pectin types (e.g., gelling, thickening, colloidal stabilization) are predetermined by their structure. The aim of this work was to explore possibility to alter structure of pectin by pilot-scale ultra-high dynamic pressure treatment, as a physical modification approach, and potentially enhance its functionality. High esterified unstandardized apple (AU) and citrus pectin (CU) solution (2.5% (m/m)) were treated by ultra-high pressure homogenizer (UHPH) at three different pressure levels and characterized with respect to their apparent viscosity, gelling behavior (gelation time, temperature and melting point), gel strength, molecular weight (MW) and on-line viscosity using size-exclusions chromatography coupled to refractive index, light scattering and online differential viscometer. The results indicated that UHPH impacted the MW in a source dependent manner. Treated CU and AU pectin exhibited a small decrease in the average MW and a more pronounced decrease in the intrinsic viscosity, likely due to more significant UHPH effect on the larger pectin molecules. In addition, the smaller (in volume) AU pectin presented a more compact conformation in solution. On the macroscopic level, those changes resulted in statistically significant decrease in apparent viscosity. UHPH CU pectin exerted decrease in gelation time and increase in gelation temperature, but not on statistically significant level. Even though treatment caused decrease in apparent viscosity of CU and AU pectin it had no effect on their respective gel strengths. From the obtained results, it can be concluded that UHPH process has a potential to modify the structure and flowing behavior of pectins, but further research is needed in order to elucidate all the changes in pectin functionality and potential benefits of this ubiquitous and multifunctional hydrocolloid treated by UHPH.

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

TAPPI Journal ◽

10.32964/tj13.2.29 ◽

2014 ◽

Vol 13 (2) ◽

pp. 29-37 ◽

Cited By ~ 1

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.

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Alkaline xylan extraction of bleached kraft pulp - effect of extraction time on pulp chemical composition and physical properties

TAPPI Journal ◽

10.32964/tj11.4.37 ◽

2012 ◽

Vol 11 (4) ◽

pp. 37-43 ◽

Cited By ~ 5

Author(s):

ESA SAUKKONEN ◽

KATJA LYYTIKÄINEN ◽

KAJ BACKFOLK

Keyword(s):

Kraft Pulp ◽

Pilot Trial ◽

Mechanical Damage ◽

Pilot Scale ◽

Extraction Time ◽

Similar Amount ◽

Alkaline Extraction ◽

Paper Properties ◽

Bleached Kraft Pulp ◽

Birch Kraft Pulp

In this pilot scale study, we examined the effects of alkaline extraction time on xylan removal, pulp and paper properties, and the consequences that need to be addressed when scaling up and intensifying the process. Alkaline extraction of bleached birch kraft pulp yields two fractions: pure polymeric xylan and pulp with reduced xylan content. Our results indicate that a similar amount of xylan can be extracted in 5 min as the amount obtained in 60 min. We found, however, that the shorter extraction time is beneficial to maintain the fiber and paper properties at an acceptable level. This pilot trial demonstrated that the washing procedure of the alkali-treated fibers must be selected with care to avoid causing mechanical damage to fibers and to avoid the loss of fines.

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Refining of birch kraft pulp before or during xylanase treatment û€“ effect on carbohydrate release and retention behavior OPEN ACCESS

Nordic Pulp & Paper Research Journal ◽

10.3183/npprj-2017-32-01-p088-097 ◽

2017 ◽

Vol 32 (01) ◽

pp. 088-097

Author(s):

Katja Lyytikäinen ◽

Kaj Backfolk

Keyword(s):

Open Access ◽

Kraft Pulp ◽

Retention Behavior ◽

Birch Kraft Pulp

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

Applied Sciences ◽

10.3390/app9163436 ◽

2019 ◽

Vol 9 (16) ◽

pp. 3436 ◽

Cited By ~ 4

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.

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VELOCITY MEASUREMENTS OF TURBULENT TWO-PHASE FLOW IN A HIGH-PRESSURE HOMOGENIZER MODEL

Chemical Engineering Communications ◽

10.1080/00986445.2012.691921 ◽

2013 ◽

Vol 200 (1) ◽

pp. 93-114 ◽

Cited By ~ 7

Author(s):

Andreas Håkansson ◽

Laszlo Fuchs ◽

Fredrik Innings ◽

Johan Revstedt ◽

Christian Trägårdh ◽

...

Keyword(s):

High Pressure ◽

Two Phase Flow ◽

Phase Flow ◽

Velocity Measurements ◽

Two Phase ◽

High Pressure Homogenizer ◽

Turbulent Two Phase Flow

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Preparation of Cellulose Nanofibrils by High-Pressure Homogenizer and Zein Composite Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.829.534 ◽

2013 ◽

Vol 829 ◽

pp. 534-538 ◽

Cited By ~ 9

Author(s):

Alireza Shakeri ◽

Sattar Radmanesh

Keyword(s):

Atomic Force Microscopy ◽

High Pressure ◽

Food Packaging ◽

Cellulose Nanofibrils ◽

Composite Films ◽

Average Diameter ◽

Nanocomposite Films ◽

Force Microscopy ◽

Atomic Force ◽

High Pressure Homogenizer

Cellulose nanofibrils ( NF ) have several advantages such as biodegradability and safety toward human health. Zein is a biodegradable polymer with potential use in food packaging applications. It appears that polymer nanocomposites are one of the most promising applications of zein films. Cellulose NF were prepared from starting material Microcrystalline cellulose (MCC) by an application of a high-pressure homogenizer at 20,000 psi and treatment consisting of 15 passes. Methods such as atomic force microscopy were used for confirmation of nanoscale size production of cellulose. The average diameter 45 nm were observed. Zeincellulose NF nanocomposite films were prepared by casting ethanol suspensions of Zein with different amounts of cellulose NF in the 0% to 5%wt. The nanocomposites were characterized by using Fourier transform infrared spectroscopy ( FTIR ), Atomic force microscopy ( AFM ) and X-ray diffraction ( XRD ) analysis. From the FTIR spectra the various groups present in the Zein blend were monitored. The homogeneity, morphology and crystallinity of the blends were ascertained from the AFM and XRD data, respectively. The thermal resistant of the zein nanocomposite films improved as the nanocellulose content increased. These obtained materials are transparent, flexible and present significantly better physical properties than the corresponding unfilled Zein films.

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