Hydrothermal processing of pine wood: effect of process variables on bio-oil quality and yield

Hydrothermal liquefaction processes (HTL) comprise complex chemical and physical transformations of biomass under the conditions of high temperature and pressure, commonly near- or supercritical water. During this processes, the components of biomass undergo various complicated chemical reactions strongly influenced by process variables. In this study, lignocellulosic biomass (pine wood) has been converted via liquefaction in subcritical water to bio-oil, water-soluble organics, gas and solid products. The process parameters (i.e. temperature and time processing) affecting the bio-oil yields and composition were comparatively studied. The chemical composition of resulting bio-oils was analyzed by means of mid-infrared spectroscopy, gel permeation chromatography, gas chromatography coupled to mass spectrometry and elemental analysis. The maximum bio-oil yield (38.35 wt.%) was obtained at 350 ºC for 10 min. The HHV of the obtained resultant bio-oils varied in the range of 24-28 MJ kg-1. Bio-oils from HTL of pine wood are complex mixtures of aromatic and cyclic compounds with numerous hydroxyl and carboxyl functional groups. The experiments exhibited that the increase in the temperature results in adeeper decomposition of biomass manifested by the higher yield of bio-oil and its gradual deoxygenation. In fact, the obtained oil products are promising, valuable intermediates, which may act as a source of many valueadded chemicals.

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Sub- and Supercritical Water Liquefaction of Kraft Lignin and Black Liquor Derived Lignin

Energies ◽

10.3390/en13133309 ◽

2020 ◽

Vol 13 (13) ◽

pp. 3309 ◽

Cited By ~ 3

Author(s):

Jukka Lappalainen ◽

David Baudouin ◽

Ursel Hornung ◽

Julia Schuler ◽

Kristian Melin ◽

...

Keyword(s):

Supercritical Water ◽

Renewable Energy Sources ◽

Black Liquor ◽

Hydrothermal Liquefaction ◽

Water Soluble ◽

Gaseous Products ◽

Bio Oil ◽

Water Conditions ◽

Oil Water ◽

Alkali Salts

To mitigate global warming, humankind has been forced to develop new efficient energy solutions based on renewable energy sources. Hydrothermal liquefaction (HTL) is a promising technology that can efficiently produce bio-oil from several biomass sources. The HTL process uses sub- or supercritical water for producing bio-oil, water-soluble organics, gaseous products and char. Black liquor mainly contains cooking chemicals (mainly alkali salts) lignin and the hemicellulose parts of the wood chips used for cellulose digestion. This review explores the effects of different process parameters, solvents and catalysts for the HTL of black liquor or black liquor-derived lignin. Using short residence times under near- or supercritical water conditions may improve both the quality and the quantity of the bio-oil yield. The quality and yield of bio-oil can be further improved by using solvents (e.g., phenol) and catalysts (e.g., alkali salts, zirconia). However, the solubility of alkali salts present in black liquor can lead to clogging problem in the HTL reactor and process tubes when approaching supercritical water conditions.

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Fuel Mixtures from Crude Glycerol, the Bio-oil–Water-Soluble Fraction, and Biochar for Stationary Applications

Energy & Fuels ◽

10.1021/acs.energyfuels.6b01964 ◽

2016 ◽

Vol 30 (10) ◽

pp. 8419-8424 ◽

Cited By ~ 11

Author(s):

Mingming Zhang ◽

Hongwei Wu

Keyword(s):

Crude Glycerol ◽

Soluble Fraction ◽

Water Soluble ◽

Water Soluble Fraction ◽

Bio Oil ◽

Oil Water ◽

Fuel Mixtures

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The component composition of planted pine wood cultivated in the boreal zone

Nordic Pulp & Paper Research Journal ◽

10.1515/npprj-2020-0058 ◽

2020 ◽

Vol 35 (4) ◽

pp. 685-693

Author(s):

D. A. Danilov ◽

A. V. Griazkin ◽

V. A. Sokolova ◽

I. V. Bacherikov

Keyword(s):

Component Composition ◽

Water Soluble ◽

Boreal Zone ◽

Lower Content ◽

Average Yield ◽

Leningrad Oblast ◽

Pine Wood ◽

Natural Stands

AbstractThe present study analyzes the composition of pine wood cultivated on artificial plantations in the Leningrad Oblast (Region). Comparing to pine wood from natural stands, a smaller heartwood zone along the height of the pine trunk and a lower content of resinous substances are noted. The content of cellulose and lignin in the heartwood and sapwood of pine is distributed differently along the trunk. The distribution of pentosans and water-soluble substances in the heartwood and sapwood along the trunk is associated with the lignin complex. The component composition of the studied pine wood from planted stands is quite uniform in its indicators if compared to the wood of older natural stands. Sulphate pulping of planted pine wood showed a higher yield of technical cellulose than the average yield from wood obtained at natural stands of the studied region.

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Glycolic acid and formic acid production from pyrolysis oil water-soluble fraction by catalytic oxidation

Chemical Engineering Science ◽

10.1016/j.ces.2021.116644 ◽

2021 ◽

Vol 239 ◽

pp. 116644

Author(s):

Dan Luo ◽

Wang Yin ◽

Depeng Han ◽

Han He ◽

Shuqian Xia

Keyword(s):

Formic Acid ◽

Catalytic Oxidation ◽

Acid Production ◽

Glycolic Acid ◽

Soluble Fraction ◽

Water Soluble ◽

Pyrolysis Oil ◽

Water Soluble Fraction ◽

Oil Water

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Characteristics of Preheated Bio-Oil Sprays Produced by an Air-Blast Injector

Volume 1: Aircraft Engine; Ceramics; Coal, Biomass and Alternative Fuels; Education; Electric Power; Manufacturing Materials and Metallurgy ◽

10.1115/gt2010-23397 ◽

2010 ◽

Cited By ~ 2

Author(s):

Heena V. Panchasara ◽

Ajay K. Agrawal

Keyword(s):

Laser Sheet ◽

Inlet Temperature ◽

Mass Ratio ◽

Ambient Conditions ◽

Air Blast ◽

Visualization System ◽

Radial Profiles ◽

Significant Difference ◽

Bio Oil ◽

Temperature And Pressure

In this study the vegetable oil (VO) is preheated to reduce the kinematic viscosity, and thus, improve atomization. A commercial air-blast atomizer is used to produce the VO spray at ambient conditions of temperature and pressure. Characteristics of the resulting spray are measured using a laser sheet visualization system and a Phase Doppler Particle Analyzer system. Experiments are conducted for VO temperatures varying from 40 C to 100 C and air to liquid mass ratio (ALR) of 2.0 and 4.0. Results show a decrease in Sauter Mean Diameter with an increase in VO temperature, regardless of the ALR. Radial profiles show larger droplets migrating towards the edge of the spray and smaller droplets in the interior spray region. Results show a significant difference in distributions of mean and root mean square axial velocity profiles as the VO inlet temperature is increased for a fixed ALR. Higher VO inlet temperature and higher ALR produced a narrower spray with smaller diameter droplets and higher peak axial velocities. Overall, this study has shown that preheating VO improves atomization by producing spray with smaller diameter droplets.

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Catalytic pyrolysis of pine wood over char-supported Fe: Bio-oil upgrading and catalyst regeneration by CO2/H2O

Fuel ◽

10.1016/j.fuel.2021.121778 ◽

2022 ◽

Vol 307 ◽

pp. 121778

Author(s):

Shasha Liu ◽

Gang Wu ◽

Syed Shatir A. Syed-Hassan ◽

Bin Li ◽

Xun Hu ◽

...

Keyword(s):

Catalytic Pyrolysis ◽

Catalyst Regeneration ◽

Pine Wood ◽

Bio Oil

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Influences of Molecular Weights on Physicochemical and Biological Properties of Collagen-Alginate Scaffolds

Marine Drugs ◽

10.3390/md19020085 ◽

2021 ◽

Vol 19 (2) ◽

pp. 85 ◽

Cited By ~ 1

Author(s):

Truc Cong Ho ◽

Jin-Seok Park ◽

Sung-Yeoul Kim ◽

Hoyeol Lee ◽

Ju-Sop Lim ◽

...

Keyword(s):

Tissue Engineering ◽

Subcritical Water ◽

Biological Properties ◽

Ethanol Solution ◽

Water Soluble ◽

Potential Candidate ◽

High Porosity ◽

Engineering Applications ◽

Molecular Weights

For tissue engineering applications, biodegradable scaffolds containing high molecular weights (MW) of collagen and sodium alginate have been developed and characterized. However, the properties of low MW collagen-based scaffolds have not been studied in previous research. This work examined the distinctive properties of low MW collagen-based scaffolds with alginate unmodified and modified by subcritical water. Besides, we developed a facile method to cross-link water-soluble scaffolds using glutaraldehyde in an aqueous ethanol solution. The prepared cross-linked scaffolds showed good structural properties with high porosity (~93%) and high cross-linking degree (50–60%). Compared with collagen (6000 Da)-based scaffolds, collagen (25,000 Da)-based scaffolds exhibited higher stability against collagenase degradation and lower weight loss in phosphate buffer pH 7.4. Collagen (25,000 Da)-based scaffolds with modified alginate tended to improve antioxidant capacity compared with scaffolds containing unmodified alginate. Interestingly, in vitro coagulant activity assay demonstrated that collagen (25,000 Da)-based scaffolds with modified alginate (C25-A63 and C25-A21) significantly reduced the clotting time of human plasma compared with scaffolds consisting of unmodified alginate. Although some further investigations need to be done, collagen (25,000 Da)-based scaffolds with modified alginate should be considered as a potential candidate for tissue engineering applications.

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