Bio-oil Components Research Articles

The Utilization of Phenol Components in Bio-Oil for Modifying Urea-Formaldehyde Resin Adhesive

The components in bio-oil are mainly concluding organic acid, aldehydes and phenolics. As the irregular cracking of the pyrolysis, the products are complex and difficult to separate. A comprehensive concept was presented and the extractions from bio-oil were used for modifying urea-formaldehyde (UF) resin in this study. Characterization by FT-IR and GC-MS indicated that the reaction mechanism. Phenol-oil addition amount and particle boards test were investigated resulted those 10% phenol-oil shows the best properties: viscosity of 73.36 mm/s, solid content of 52.25% and pH of 8.35 and the best pressing condition is 125°C for 5min which produce a 1.23MPa bond strengthen and 1.05 mg/L formaldehyde emission plywood.

Upgrading of bio-oil to boiler fuel by catalytic hydrotreatment and esterification in an efficient process

Bio-oil can't be directly used as fuel due to its deteriorate properties. Here, an efficient catalytic upgrading process for the bio-oil, including esterification, hydrogenation, hydrodeoxygenation and depolymerization, is proposed with multifunctional catalyst Ni/SiO2–ZrO2 and biomass-derived solvent ethanol. Results showed that esters, alcohols, phenolics, and cyclo-ketones were the main components in the upgraded bio-oil while aldehydes were removed completely via catalytic hydrogenation and acids were removed by catalytic esterification with supercritical ethanol. The pH value of upgraded bio-oil rose drastically from 2.38 to 5.24, and the high heating value increased to 24.4 MJ kg−1. Comparison characterization on the upgraded and crude bio-oil using FT-IR, GPC (Gel permeation chromatography) and 13C NMR (Nuclear Magnetic Resonance) demonstrated that lignin-derived oligomers contained in crude bio-oil were further depolymerized over Ni/SiO2–ZrO2 catalyst. The improved properties suggest that the upgraded bio-oil is more suitable to be used as boiler fuel. Furthermore, the loss of carbon is negligible because formation of coke is suppressed during the upgrading process.

Characterization of liquefaction bio-oil from sewage sludge and its solubilization in diesel microemulsion

Liquefaction bio-oil from sewage sludge using different organic solvent (methanol, ethanol or acetone) at temperature of 260–380 °C was characterized in terms of its elemental and chemical composition, and was further upgraded by microemulsion technology. The bio-oil obtained had high carbon content of 67.60–73.58% and was mainly composed of esters when methanol or ethanol was used as liquefaction solvent, or esters, ketones, alcohols and phenols when acetone was used, meaning its great potential to be used as fuel. Diesel extraction procedure found that ethyl esters were the least diesel-solvable compounds in diesel among the main components of the liquefaction bio-oil, while methyl esters were extracted completely. The bio-oil obtained with methanol as solvent, compared to acetone or ethanol, and the bio-oil obtained at higher liquefaction temperature was easier to be upgraded by water/diesel microemulsion in terms of Span 80 consumption. In addition, the stability mechanism of the component of liquefaction bio-oil in the water/diesel/bio-oil microemulsion was proposed. The diesel-insolvable fractions, e.g. part of ethyl esters, were probably solubilized in the water phase or inserted between surfactants; while the diesel-solvable fractions, e.g. methyl esters, part of ethyl esters, ketones, alcohols and phenols, were probably dissolved in the diesel phase.

Measurement of activity coefficient at infinite dilution for some bio-oil components in water and mass transfer study of bubbles in the dilutor

Activity coefficients at infinite dilution (γ∞) values are of great importance when designing separation processes like distillation, liquid–liquid extraction and gas stripping. In this study the γ∞ values were determined for four compounds in water that are present in bio-oil. Henry’s law constants (H12), Partial molar excess enthalpies at infinite dilution (H¯iE,∞) and air–water partition coefficients (Kaw) are also reported. The measurements were performed using inert gas stripping equipment (dilutor) in the 298–340K temperature range. Mass transfer study was also performed to investigate the equilibrium between the solution and the gas leaving the cell.

RAFT polymerization and associated reactivity ratios of methacrylate-functionalized mixed bio-oil constituents

High separations costs reduce the practicality of polymers sourced from renewable bio-oils, motivating economical multicomponent bio-oil polymerizations. Thus, this paper investigates polymerization behavior of model bio-oil components and their mixtures.

Upgrading of Lignin-Derived Bio-oil Components Catalyzed by Pt/γ-Al2O3: Kinetics and Reaction Pathways Characterizing Conversion of Cyclohexanone with H2

The conversion of cyclohexanone catalyzed by Pt/γ-Al2O3 in the presence of H2 was investigated with a fixed-bed tubular flow reactor at temperatures in the range of 573–673 K, a pressure of 14 bar, and space velocities in the range of 3–120 g of cyclohexanone/(g of catalyst × h). Data determined at low conversions of cyclohexanone identify the kinetically significant reaction classes (hydrogenation, dehydrogenation, hydrodeoxygenation, dehydration, and condensation) and quantitatively represent the initial product distribution. The pseudo-first-order rate constants for formation of the main products of cyclohexanone conversion under initial reaction conditions decrease in the following order: phenol > 2-cyclohexylidenecyclohexan-1-one > 2-methylphenol > cyclohexylbenzene > cyclohexane > biphenyl > 2-cyclohexen-1-one > 2-cyclohexylcyclohexan-1-one > 2-phenylphenol > cyclohexene > 2-cyclohexylphenol. The apparent activation energy for the dehydrogenation reaction that leads to phenol formation is approximat...

Modeling the Kinetics of Deactivation of Catalysts during the Upgrading of Bio-oil

The fouling of catalysts for the upgrading of bio-oils appears to be very different from the fouling of catalysts for the hydroprocessing of petroleum-derived streams. There are two reasons for the differences: (a) bio-oil contains polarizable components and phases that can stabilize reaction intermediates exhibiting charge separation and (b) bio-oil components contain functional groups that contain O, notably carbonyls (>C═O). Aldol condensation of carbonyls affords very different pathways for the production of oligomeric, refractory deposits than does dehydrogenation/polymerization of petroleum-derived hydrocarbons. Colloquially, we refer to the bio-oil-derived deposits as “gunk” to discriminate them from coke, the carbonaceous deposits encountered in petroleum refining. Classical gelation appears to be a suitable model for the “gunking” reaction. Our work has helped explain the temperature range at which bio-oil should be preprocessed (“stabilized”) to confer longer lifetimes on the catalysts used for more severe processing. Stochastic modeling (kinetic Monte Carlo simulations) appears promising to capture the rates of oligomerization of bio-oil.

Catalytic Hydrogenation of Alkali Lignin to Bio-oil Using Fullerene-like Vanadium Sulfide

The catalytic conversion of alkali lignin to chemicals has been the subject of intense research efforts during the past few decades. In this study, VS2 catalysts, with different morphologies of sheets and nanoflowers, were prepared through hydrothermal methods and applied to the hydrogenation of alkali lignin. The conversion of alkali lignin and yield of bio-oil are 77.02 and 58.75%, respectively, at 250 °C under 2 MPa H2 for 1.5 h with a VS2 sheets catalyst, which is higher than that of a flower-like VS2 catalyst. It was found that mainly the components of bio-oil were phenols, important and useful chemicals in transportation fuels and chemical industries. Our results indicated that the prepared VS2 catalyst can be used as an effective material for degrading biomass to obtain valuable chemicals.

Converting pine sawdust to advanced biofuel over HZSM-5 using a two-stage catalytic pyrolysis reactor

In this study, the pine sawdust thermal conversions over HZSM-5 catalyst were carried out under different reaction temperatures in a two-stage catalytic pyrolysis reactor. Higher temperatures in the catalytic reactor tended to decrease the yield of bio-oil and change the component of bio-oil. The results from the gas chromatography–mass spectrometry (GC–MS) analysis showed that the pyrolysis reaction at 500°C and catalytic reaction at 500°C treatment obtained the highest hydrocarbon content (58.63%) and the highest C8–C12 content (48.03%) in the oil phase of the bio-oil. The X-ray diffraction (XRD) and selected-area-electron-diffraction (SEAD) characterization showed that the distortion of the ZSM-5 zeolite lattice occurred before and after use. The Brunauer–Emmett–Teller (BET) characterization indicated that the formation of coke increased as the catalytic temperature rose. The physical characterization of bio-oils, such as water content, density, viscosity, pH, and higher heating value (HHV) further demonstrated that HZSM-5 catalyst was beneficial in achieving low viscosity and higher HHV bio-oils. All the results suggest that the two-stage catalytic pyrolysis reactor with HZSM-5 catalyst has a great potential for achieving advanced biofuel.

Sustainable production of aromatics from bio-oils through combined catalytic upgrading with in situ generated hydrogen

Pyrolysis liquids or bio-oils from rice husks are selectively converted into aromatics through a combined catalytic process, which includes two sequent steps: reforming and upgrading. Hydrogen from methanol and low-weight molecules in bio-oil is in situ generated in the reforming reactor. Methanol (16wt% of total bio-oils) is added not only as the hydrogen donor, but also as polar solvent for homogenizing bio-oil and reducing its viscosity. Structured nickel nets are used as both the reforming catalyst and heating grid for gasifying high-boiling-point components of bio-oil. In the upgrading reactor, the combination of Co–Ru–Zr/silica with Pt-ZSM-5 gives the highest yield of aromatics (53.7%) and the lowest coke deposition (7.1%). Hydrogen for deoxygenation is generated from reforming of added methanol and low-weight molecules in bio-oil. Coke formation during fixed-bed upgrading can be significantly suppressed through the combined catalytic process.

Influence of solvent on upgrading of phenolic compounds in pyrolysis bio-oil

Solvents play a pivotal role in many chemical reactions as well as in upgrading of pyrolysis bio-oil. Herein we report a systematic study of the effects of solvents such as water, methanol, ethanol, propanol, butanol, acetone, ethyl acetate, tetrahydrofuran and hexane on hydrogenation of a lignin-derived component of pyrolysis bio-oil, phenol, over activated carbon supported palladium catalysts. The solvents were classified into four groups so as to better understand the effect of them. For hydrogen bond donor–hydrogen bond acceptor (HBD–HBA) solvents and hydrogen bond acceptor (HBA) solvents, the conversion of phenol decreased with increasing polarity/polarizability π*. Phenol was converted completely in hexane or water at 250 °C. However, in methanol or ethanol, it was converted partially. Synergistic action of multiple factors had an effect on the hydrogenation of phenol. To convert phenol better, water and hexane as solvents were excellent in upgrading of pyrolysis bio-oil.

Characterization of bio-oil and biochar from high-temperature pyrolysis of sewage sludge

The influence of temperature (550–850°C) on the characteristics of bio-oil and biochar from the pyrolysis of sewage sludge (SS) in a horizontal tube reactor was investigated. Results showed that when the pyrolysis temperature increased from 550°C to 850°C, the yield of bio-oil decreased from 26.16% (dry ash-free basis) to 20.78% (dry ash-free basis). Main components of bio-oil were phenols, esters, cholests, ketones, amides, indoles, and nitriles. Besides, the elevated heating rate of 25°C/min was demonstrated to favour the complete combustion of bio-oil. Moreover, caused by the increase in temperature, the yield of biochar decreased from 54.9 to 50.6wt%, Brunauer–Emmet–Teller surface area increased from 48.51 to 81.28 m2/g. Furthermore, pH was increased from 5.93 of SS to 7.15–8.96 of biochar. The negative ζ-potential was also strengthened (−13.87 to −11.30 mV) and principal functional groups on the surface of biochar were –OH, C=O, C=C, –NO2, and S=O.

Direct hydrothermal liquefaction of undried macroalgae Enteromorpha prolifera using acid catalysts

Direct liquefaction of macroalgae Enteromorpha prolifera without predrying treatment was performed in a batch reactor. Effects of temperature, reaction time, biomass-to-water ratio and acid catalysts (sulfuric acid and acetic acid) on liquefaction products were investigated. Raw material and liquefaction products were analyzed by elemental analysis, Fourier transform infrared (FT-IR) and gas chromatography–mass spectrometry (GC–MS). Results showed that liquefaction at 290°C for 20min with 1:3 biomass-to-water ratio produced the highest bio-oil yield of 28.4wt%, and high heating value (HHV) was 29.5MJ/kg. Main components of bio-oil were fatty acids, ketones, alkenes and 5-methyl furfural, and main components of water soluble organics (WSOs) were pyridines, carboxylic acids and glycerol. In the bio-oil obtained with acid catalysts, content of ketones significantly increased while alkenes disappeared. Content of 5-methyl furfural also increased. Flow property of bio-oils was improved in the presence of acid catalysts. Moreover, esters were formed when adding sulfuric acid.

Implementation of concepts derived from model compound studies in the separation and conversion of bio-oil to fuel

Thermal conversion of biomass via pyrolysis, torrefaction, or liquefaction is an attractive process with significant economic potential. The main challenge of this technology is the upgrading of the intermediate liquid product (bio-oil) due to its complex composition. The components of bio-oil can be divided into light aqueous soluble oxygenates, furanics, phenolics, sugars and anhydrosugars, and larger oligomers. Since any single upgrading approach can only target the conversion of one or two families of compounds a combination of separation and conversion is necessary.A number of fundamental studies with model compounds have been done in the last few years and important concepts about reaction mechanisms and nature of active catalysts have been developed. Unfortunately, the complexity of bio-oil has hampered the impact of these fundamental studies on the practical applications. It is an important challenge to predict how each compound or family of compounds will behave over a catalyst in the presence of other families, when the entire mixture is fed. It is important to take into account that catalysts may quickly deactivate if the entire bio-oil is present, even when they were effective in the presence of a more pure stream. This knowledge should help guide the separation to evaluate the most effective catalytic upgrading strategies. The present review highlights recent advancements made with the conversion of model compounds present in bio-oil, as well as strategies to combine this knowledge with separation advancements in an effort to increase the amount of carbon in the biomass that can be economically converted to fuels and chemicals.

Catalytic conversion of waste particle board and polypropylene over H-beta and HY zeolites

The catalytic copyrolysis of waste particle board (WPB) and polypropylene (PP) was investigated for the first time over HY (5.1), HY (30), H-Beta and Ga/H-Beta catalysts. The catalysts were characterized by BET and NH3-TPD analyses. The catalytic pyrolysis of the WPB increased the production of gas products (CO, CO2, C1–C4) compared to non-catalytic pyrolysis. Acids and levoglucosan, which are the main components of bio-oil produced from non-catalytic pyrolysis, were converted to more valuable aromatics, phenolics, and furans through dehydration, deoxygenation and aromatization. The most abundant products from the copyrolysis of WPB and PP were large-molecular-mass hydrocarbons (≥C10). However, catalytic copyrolysis increased the yields of small-molecular-mass hydrocarbons in the gasoline range, aromatics and phenolics. The water content in bio-oil was reduced significantly by copyrolysis with PP, contributing to the improvement in oil quality. HY (5.1) with the largest number of acid sites showed higher catalytic activity than HY (30) and H-Beta because the decomposition and reforming reactions during catalytic copyrolysis occurred on the acid sites of the catalysts. Ga/H-Beta showed even higher selectivity toward the aromatics than H-Beta despite the smaller quantity of acid sites, suggesting that Ga promoted the dehydrocyclization of the reaction intermediates.

Conversion of Guaiacol on Noble Metal Catalysts: Reaction Performance and Deactivation Studies

Guaiacol, a phenol derived compound produced by the thermal degradation of lignin, was selected as a model compound to study the catalytic hydrodeoxygenation (HDO) process for upgrading pyrolysis bio-oils. Guaiacol is among the major components of bio-oils; however, it is thermally unstable which leads to catalyst deactivation. In the present study, four noble metal catalysts (Pt, Pd, Rh, and Ru) supported on activated carbon were tested in a fixed-bed reactor at atmospheric pressure and their performance for the guaiacol HDO process was measured. Our results showed that, among the tested catalysts, Pt has higher deoxygenation activity and shows little deactivation for 5 h. Additionally, the operating temperature for the Pt catalyst was optimized and found to be 300 °C. Finally, results from catalyst characterization demonstrated that polyaromatic deposits, especially the condensed ring compounds, are the most likely cause for catalyst deactivation.

Dual application of duckweed and azolla plants for wastewater treatment and renewable fuels and petrochemicals production

BackgroundShortages in fresh water supplies today affects more than 1 billion people worldwide. Phytoremediation strategies, based on the abilities of aquatic plants to recycle nutrients offer an attractive solution for the bioremediation of water pollution and represents one of the most globally researched issues. The subsequent application of the biomass from the remediation for the production of fuels and petrochemicals offers an ecologically friendly and cost-effective solution for water pollution problems and production of value-added products.ResultsIn this paper, the feasibility of the dual application of duckweed and azolla aquatic plants for wastewater treatment and production of renewable fuels and petrochemicals is explored. The differences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by these aquatic macrophytes were used as the basis for optimization of the composition of wastewater effluents. Analysis of pyrolysis products showed that azolla and algae produce a similar range of bio-oils that contain a large spectrum of petrochemicals including straight-chain C10-C21 alkanes, which can be directly used as diesel fuel supplement, or a glycerin-free component of biodiesel. Pyrolysis of duckweed produces a different range of bio-oil components that can potentially be used for the production of “green” gasoline and diesel fuel using existing techniques, such as catalytic hydrodeoxygenation.ConclusionsDifferences in absorption rates of the key wastewater nutrients, ammonium and phosphorus by different aquatic macrophytes can be used for optimization of composition of wastewater effluents. The generated data suggest that the composition of the petrochemicals can be modified in a targeted fashion, not only by using different species, but also by changing the source plants’ metabolic profile, by exposing them to different abiotic or biotic stresses. This study presents an attractive, ecologically friendly and cost-effective solution for efficient bio-filtration of swine wastewater and petrochemicals production from generated biomass.

Fixed-bed catalytic and non-catalytic empty fruit bunch biomass pyrolysis

An attempt to the global clarion call to explore for an alternative source of environmentally friendly, renewable and cheaper energy (fuel) source than the conventional fossil fuel, was made in this study. This involved testing the effects of three catalysts (potassium carbonate K2CO3, calcium hydroxide Ca(OH)2 and magnesium oxide MgO) in the empty fruit bunch (EFB) pyrolysis on the product yields. The Ca(OH)2 catalyzed EFB pyrolysis gave the maximum percentage yield (42.64%) of bio-oil. The maximum bio-oil percentage yield from the Ca(OH)2 catalyzed EFB pyrolysis was obtained at pyrolysis temperature of 600°C, sweeping gas flow rate of 200mL/min and using 10wt.% of the catalyst. The GC–MS analysis of the Ca(OH)2 catalyzed EFB pyrolysis showed an increase (10.68%) in the desirable phenolic content and a reduction (35.21%) in the undesirable acidic components of the bio-oils when compared with the phenolic (16.74%) and acidic (42.88%) components of non catalyzed EFB pyrolysis bio-oil. This study has revealed that the quantity and quality of bio-oils can be improved using Ca(OH)2 catalyzed biomass pyrolysis.

Application of Aquatic Plants for the Treatment of Selenium-Rich Mining Wastewater and Production of Renewable Fuels and Petrochemicals

Aquatic plants aggressively colonising wetlands are widely used for the biosorption of the soluble contaminants from wastewater and represent an attractive feedstock for biofuel production. Three common Australian aquatic plants, duckweed (Landoltia punctata), elodea, (Elodea canadensis) and water clover (Marsilea quadrifolia), colonizing different depths of wetlands were tested for their ability to treat the selenium-rich mining wastewater and for their potential for production of petrochemicals. The results showed that these plants could be effective at biofiltration of selenium and heavy metals from mining wastewater accumulating them in their fast growing biomass. Along with production of bio-gas and bio-solid components, pyrolysis of these plants produced a range of liquid petrochemicals including straight-chain C14-C20 alkanes, which can be directly used as a diesel fuel supplement or as a glycerine-free component of biodiesel. Other identified bio-oil components can be converted into petrochemicals using existing techniques such as catalytic hydrodeoxygenation. A dual application of aquatic plants for wastewater treatment and production of value-added chemicals offers an ecologically friendly and cost-effective solution for water pollution problems and renewable energy production.

Direct Infusion Mass Spectrometric Analysis of Bio-oil Using ESI-Ion-Trap MS

Direct infusion-electrospray ionization (ESI)-Ion-Trap MS and ESI-Ion-Trap MS² were used for direct analysis of bio-oil from forest residue and reference bio-oils from cellulose and hardwood lignin. It was found that the bio-oil concentration and mode of MS analysis are important parameters in obtaining reproducible and structurally informative data. In order to study sensitivity and selectivity with ESI-Ion-Trap MS, a selection of model compounds were studied with and without dopants. Dopants included NaCl, formic acid and NH₄Cl in positive ion mode and NaOH and NH₄Cl in negative ion mode. NH₄Cl addition can be used to distinguish carbohydrate-derived products from other bio-oil components. NaOH and NaCl additives produced the highest peak intensities in negative ion mode as deprotonated adducts and in positive mode as sodiated adducts, respectively. ESI-MS² was used successfully for confirmation of individual target ions such as levoglucosan and cellobiosan, as well for some structural products of lignin. Simple bio-oil fractionation into hydrophilic and hydrophobic components provided less complex and more interpretive ion spectra.