scholarly journals Effect of drying on the hydroxyl accessibility and sorption properties of pressurized hot water extracted wood

2021 ◽  
Author(s):  
Suvi Kyyrö ◽  
Michael Altgen ◽  
Hanna Seppäläinen ◽  
Tiina Belt ◽  
Lauri Rautkari
Keyword(s):  
Moisture Content ◽  
Hot Water ◽  
Sorption Properties ◽  
Water Extraction ◽  
Hydroxyl Groups ◽  
Hot Water Extraction ◽  
Oven Drying ◽  
Hygroscopic Properties ◽  
Hemicellulose Removal ◽  
Water Saturated

AbstractHot water extraction (HWE) treatment changes the physicochemical properties of the wood, including hygroscopic properties. HWE treatment decreases the hydroxyl accessibility of the wood, but the relevance of other mechanisms that change hygroscopic properties are not fully understood. This study investigates the effect of drying on the hydroxyl accessibility and sorption properties of wood. Pressurized hot water extraction (HWE) treatment was applied at 140 °C for 1–5 h to Scots pine (Pinus sylvestris L.) sapwood samples in order to remove increasingly more hemicellulose from the cell wall matrix. Following HWE treatment, half of the wood samples were oven-dried and then re-soaked, while the other half was kept in a fully saturated state. The samples were investigated by applying a new approach that was based on the deuteration of accessible hydroxyl groups, which was followed by the measurement of mass loss due to re-protonation. Sorption properties of the wood samples were studied by measuring moisture content, sorption isotherms and dimensional changes. The present results showed that accessible hydroxyl group content decreased only due to hemicellulose removal during the HWE treatment and was unaffected by oven-drying. However, oven-drying enhanced the effect of HWE treatments in reducing the water-saturated dimensions and the moisture content of wood. Therefore, the additional reductions in hygroscopicity and water-saturated dimensions were not related to changes in sorption site density.

scholarly journals Effect of hot water extracted hardwood and softwood chips on particleboard properties

Holzforschung ◽  
2014 ◽  
Vol 68 (7) ◽  
pp. 807-815 ◽  
Author(s):  
Manuel Raul Pelaez-Samaniego ◽  
Vikram Yadama ◽  
Tsai Garcia-Perez ◽  
Eini Lowell ◽  
Thomas Amidon
Keyword(s):  
Mechanical Properties ◽  
Liquid Fraction ◽  
Hot Water ◽  
Hydroxyl Groups ◽  
Moisture Uptake ◽  
Thickness Swelling ◽  
Hot Water Extraction ◽  
Hemicellulose Removal ◽  
Wood Resistance ◽  
Particleboard Properties

Abstract The affinity of particleboard (PB) to water is one of the main limitations for using PB in moisture-rich environments. PB dimensional stability and durability can be improved by reducing the available hydroxyl groups in wood through hemicellulose removal, for example, by hot water extraction (HWE), which increases wood resistance to moisture uptake. The resulting liquid fraction from HWE is rich in hemicelluloses and can be used for chemicals and fuels, and the solid fraction is less hydrophilic. The objective of this study was to investigate the effects of HWE of softwood chips (conducted at 160°C and 90 min) and hardwood chips (160°C and 120 min) on the properties of PB panels. HWE increased compressibility and reduced springback by 34% and 44% for pine and maple chips, respectively, which positively impacted the PB properties. Water absorption of pine PB panels was lowered by 35% and that of maple PB panels by 30%, while reduction of thickness swelling was lowered by 39% for pine PB and 56% for maple PB after 24 h of immersion in water. The mechanical properties were not significantly affected.

scholarly journals Structural and Thermal Analysis of Softwood Lignins from a Pressurized Hot Water Extraction Biorefinery Process and Modified Derivatives

Molecules ◽  
2019 ◽  
Vol 24 (2) ◽  
pp. 335 ◽  
Author(s):  
Lucas Lagerquist ◽  
Andrey Pranovich ◽  
Ivan Sumerskii ◽  
Sebastian von Schoultz ◽  
Lari Vähäsalo ◽  
...  
Keyword(s):  
Chemical Properties ◽  
Hot Water ◽  
Water Extraction ◽  
Hydroxyl Groups ◽  
Gravimetric Analysis ◽  
Hot Water Extraction ◽  
Pressurized Hot Water Extraction ◽  
Lignin Fraction ◽  
Carboxylic Groups ◽  
Nmr Techniques

In this work we have analyzed the pine and spruce softwood lignin fraction recovered from a novel pressurized hot water extraction pilot process. The lignin structure was characterized using multiple NMR techniques and the thermal properties were analyzed using thermal gravimetric analysis. Acetylated and selectively methylated derivatives were prepared, and their structure and properties were analyzed and compared to the unmodified lignin. The lignin had relatively high molar weight and low PDI values and even less polydisperse fractions could be obtained by fractionation based on solubility in i-PrOH. Condensation, especially at the 5-position, was detected in this sulphur-free technical lignin, which had been enriched with carbon compared to the milled wood lignin (MWL) sample of the same wood chips. An increase in phenolic and carboxylic groups was also detected, which makes the lignin accessible to chemical modification. The lignin was determined to be thermally stable up to (273–302 °C) based on its Tdst 95% value. Due to the thermal stability, low polydispersity, and possibility to tailor its chemical properties by modification of its hydroxyl groups, possible application areas for the lignin could be in polymeric blends, composites or in resins.

scholarly journals Effect of hot-water extraction on the hygroscopicity, shrinkage, and swelling of Paulownia tomentosa wood

BioResources ◽  
2020 ◽  
Vol 16 (1) ◽  
pp. 1276-1286
Author(s):  
Jae-Ik Jo ◽  
Seong-Hyun Kim ◽  
Do-Hoon Kim ◽  
Byantara Darsan Purusatama ◽  
Intan Fajar Suri ◽  
...  
Keyword(s):  
Moisture Content ◽  
Tangential Direction ◽  
Hot Water ◽  
Water Extraction ◽  
Extractive Content ◽  
Water Vapor Absorption ◽  
Hot Water Extraction ◽  
Before And After ◽  
Shrinkage And Swelling ◽  
American Society

Liquid water and water vapor absorption on each separate surface and all surfaces at once, as well as the oven-dry shrinkage before and after the hot-water extraction of the wood, were examined using Korean Standards. The extractives content was examined using American Society for Testing and Materials (ASTM) standards. The highest water absorption and moisture adsorption were found in the transverse sections of both unextracted and extracted wood samples. There was no change in the equilibrium moisture content (EMC) in the unextracted vs. extracted wood samples at a relative humidity (RH) of 75%. However, the EMC in the extracted sample was higher than that in the unextracted sample at a RH of 90%. Swelling per 1% moisture content remained unchanged in the radial direction before and after extraction, while it increased in the tangential direction. The linear and volumetric shrinkage, as well as the coefficient of anisotropy, considerably increased after extraction. There was no difference in the extractive content between sapwood and heartwood. In conclusion, it was confirmed that the extractives in wood considerably affect the hygroscopicity and shrinkage of Paulownia wood.

Hemicellulose extraction and its effect on pulping and bleaching

TAPPI Journal ◽  
2013 ◽  
Vol 12 (10) ◽  
pp. 45-52 ◽  
Author(s):  
TROY RUNGE ◽  
CHUNHUI ZHANG
Keyword(s):  
Degradation Products ◽  
Cellulose Degradation ◽  
Hot Water ◽  
Water Extraction ◽  
Fiber Morphology ◽  
Hot Water Extraction ◽  
Hemicellulose Content ◽  
Elemental Chlorine ◽  
Liquid Hot Water ◽  
Hemicellulose Removal

A potential biorefinery is envisioned to use the hemicellulose portion of biomass to create transportation fuels or chemicals and the cellulose portion for fiber to be used in papermaking. To understand the effect on hemicellulose removal to pulpability and bleachability, a liquid hot water extraction was performed on two types of biomass with high hemicellulose content: poplar and miscanthus. The resulting materials were pulped using either a soda anthraquinone or kraft process. The pulps were then oxygen delignified and bleached with an elemental chlorine free sequence. The results demonstrate that a significant portion of hemicellulose can be extracted using liquid hot water extraction conditions of 170°C, 60 min, and a 6:1 ratio, with minimal glucan degradation. These low hemicellulose-content pulps delignified similarly to the control pulp, but had lower oxidative demand because of the absence of hemicellulose degradation products. Oxygen delignification of the low hemicellulose-content pulps was enhanced, but so was cellulose degradation. The delignification gains resulted in higher brightness ceilings for the pulps when a D(EP)D sequence was used. Measured fiber morphology did not change significantly from extracting the hemicellulose. Overall, hemicellulose extraction before pulping improved the efficiency of pulping and bleaching materials to a high brightness, but increased cellulose degradation.

Effect of Ultrasonic Wave on Lentinan Extraction

2011 ◽  
Vol 291-294 ◽  
pp. 1339-1343
Author(s):  
Wen Bo Zhang ◽  
Hong Rui Li ◽  
Jun Tao ◽  
Bing Bing Dong
Keyword(s):  
Extraction Efficiency ◽  
Hot Water ◽  
Water Extraction ◽  
Extraction Technique ◽  
Orthogonal Experimental Design ◽  
Extraction Temperature ◽  
Lentinus Edodes ◽  
Extraction Condition ◽  
Hot Water Extraction ◽  
Extraction Parameters

The research in this paper optimized the extraction technique of lentinan with ultrasonic assistant method on the basis of hot water extraction technique, and investigated the promoting function of ultrasound to polysaccharides extraction. Extraction condition was selected by means of orthogonal experimental design, four factors and three levels L9(34), after key elements were respectively chosen through single factor experiments. Comparison between optimal extraction parameters of two method, hot water extraction technique and ultrasonic assistant extraction technique, showed decreased extraction temperature and significantly shortened extraction time, which existed in the second means, improved the extraction efficiency. Lentinus edodes polysaccharide extracted with ultrasonic assistant technique, the extraction rate and polysaccharide content percentage increased 6.22% and 8.66% respectively, comparative to which extracted with hot water extraction technique.

scholarly journals Optimization of the extraction of galactoglucomannans from Pinus halepensis

Holzforschung ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Nacera Benouadah ◽  
Andrey Pranovich ◽  
Djamel Aliouche ◽  
Jalel Labidi ◽  
Stefan Willför
Keyword(s):  
High Performance ◽  
Pinus Halepensis ◽  
Hot Water ◽  
Water Extraction ◽  
Chemical Degradation ◽  
Extraction Time ◽  
Size Exclusion ◽  
Hot Water Extraction ◽  
Extraction Processes ◽  
Extraction Parameters

AbstractThe effectiveness of pressurized hot-water extraction conditions for obtaining galactoglucomannans (GGMs) from Pinus halepensis suitable for applications like coatings and films packaging was investigated. For this purpose, high molar masses with high yields are required, presenting a serious challenge for hot-water extraction processes. The extraction of GGMs was carried out in an accelerated solvent extractor (ASE) and the isolation was performed by precipitation in ethanol. Three temperatures in the range 160–180 °C and five extraction times 5–90 min were tested in order to optimize extraction parameters of GGMs, avoiding thermal and chemical degradation in hot-water. Total dissolved solids (TDS) were determined gravimetrically after freeze-drying and weight average molar masses (Mw) were determined by high-performance size exclusion chromatography (HPSEC). Total non-cellulosic carbohydrates were determined by gas chromatography (GC) after acid methanolysis. Free monomers were additionally analyzed by GC. Lignin in water extracts was measured by an ultraviolet (UV) method. Acetic acid was determined after alkaline hydrolysis of acetyl groups and analyzed by HPSEC. The main parameters influencing the extraction processes of the GGMs, namely, extraction time and temperature were studied. Optimal extraction parameters of GGMs were identified at 170 °C and 20 min extraction time, with average Mw of extracted fraction of 7 kDa leading to a GGM yield of approximately 56 ${\text{mgg}}_{\text{o}.\text{d}.\text{m}}^{-1}$, corresponding to 6% on dry wood basis.

Extraction of carboxylic acid-containing diterpenoids from Dodonaea viscosa via pressurised hot water extraction

Fitoterapia ◽  
2018 ◽  
Vol 126 ◽  
pp. 65-68 ◽  
Author(s):  
Bianca J. Deans ◽  
Wesley J. Olivier ◽  
David Girbino ◽  
Alex C. Bissember ◽  
Jason A. Smith
Keyword(s):  
Carboxylic Acid ◽  
Hot Water ◽  
Water Extraction ◽  
Dodonaea Viscosa ◽  
Hot Water Extraction
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