Characterization Of Bio-oil Research Articles

Upgrading of bio-oil from palm kernel shell by catalytic cracking in the presence of HZSM-5

ABSTRACTUpgrading of bio-oil extracted from palm kernel shell (PKS) was performed using a lab-scale fixed-bed reactor with HZSM-5 as a catalyst. The catalytic cracking was carried out at optimized conditions: 0.3-MPa pressure, temperature of 500°C, and oil to catalyst ratio of 1:5. One of the challenges in upgrading bio-oil by catalytic cracking is deactivation of catalyst due to coke formation on catalyst surface. To overcome coke deposition, the upgrading process was carried out at 0.3-MPa pressure. Characterization of raw and upgraded bio-oil obtained through catalytic cracking was discussed in detail, indicating improvement in its physical properties. The distribution of products after cracking of bio-oil includes 58.89 wt% of organic liquid product, 15.63 wt% of aqueous fraction, 7.84 wt% of coke, and 17.64 wt% of gases. The degree of deoxygenation and calorific value of organic liquid product is 43.74% and 31.65 MJ/kg respectively. Organic liquid product obtained comprises 17.55% of hydrocarbons within the gasoline range. Hence, HZSM-5 proved its effectiveness for upgrading the bio-oil in a continuous mode.

Pyrolysis of Jatropha Curcas seed cake followed by optimization of liquid⿿liquid extraction procedure for the obtained bio-oil

Lignocellulosic biomass is considered an abundant and renewable source to produce bio-oils with an objective of its value addition for fuels and chemicals. Upgrading strategies have immensely evolved as a result of ever progressing research in this field. Development of complete analytical protocol for bio-oil characterization at different stages of its production, storage, upgrading and during its use is essential for the purpose of its quality assurance and understanding. This report is aimed at developing a sample preparation procedure for bio-oils involving an extensive liquid⿿liquid extraction approach. Bio-oil obtained after slow pyrolysis of Jatropha Curcas seed cake was phase separated and subjected to solvent extraction. Various solvents were screened for their extraction capabilities towards available organic compounds of all functional group in the bio-oil. Ethyl acetate, dichloromethane, carbon tetrachloride, diethyl ether, benzene, cyclohexane and hexane were employed for extraction of aqueous phase under similar conditions. Recoveries of compounds containing varying functional groups indicated ethyl acetate and dichloromethane as optimum among all other solvents. During the extraction, partitioning of compounds between bio-oil phase and solvent occurred largely on the basis of polarity. Acidic and basic organic compounds present in the aqueous phase were determined after adjusting the pH of samples followed by dichloromethane extraction. A comprehensive detail of the extracted chemicals and their classification has been provided. The identification was carried out qualitatively with GC⿿MS and derivatization of polar chemicals was also carried out before analysis. These experiments compare the efficacy of various organic solvents for extracting diverse bio-oil pyrolytic products. The findings are important in ascertaining usefulness of organic solvents towards enrichment of available bio-oil chemical groups. The information may be either utilized for characterization purposes or their monitoring during upgrading process.

Production and characterization of bio oil and bio char from flax seed residue obtained from supercritical fluid extraction industry

Fast pyrolysis of the flax seed residue was carried out in a semi-batch reactor with an aim to study the product distribution and to identify optimum temperature condition for maximizing the bio-oil yield. The effect of temperature on product distribution, elemental composition, and physical properties of major products of pyrolysis such as bio oil and bio char was investigated. The maximum condensable fraction yield was found to be 50.66 wt% at a pyrolysis temperature of 500 °C, out of which the amount of bio-oil excluding the aqueous layer was 31 wt.%. The chemical composition of bio-oil obtained at optimum condition is analyzed using CHNS analyzer, FTIR and GC-MS. Fuel properties are also determined using IS methods. The bio oil was found to have higher calorific value than the feedstock. Again, it was found slightly basic in nature owing to the presence of higher concentration of basic components than acidic components. The char was characterized for elemental composition, heating value and surface area.

Characterization of bio-oils obtained from pyrolysis of bocaiuva residues

Brazilian food industry employs several kinds of fruits in manufacturing food products, including the bocaiuva fruit (Acrocomiaaculeata). The two-dimensional gas chromatography with mass spectrometric detector (GC × GC/TOFMS) was employed to analyze bio-oils generated from the endorcap, bark and fiber of bocaiuva residues. The bio-oil generated from the endocarp proved to be of the highest complexity in the set with 151 tentatively identified compounds. On the other hand, the bio-oils generated from the bark and the fiber led to 111 and 78 tentatively identified compounds, respectively. Using standards, 24 compounds (59.91% of the total) were confirmed in the bio-oil of bark, while 28 compounds (42.23%) and 19 compounds (47.60%) were confirmed for fiber and endocarp bio-oils, respectively. In bio-oils of endocarp and bark the compounds were identified and classified as phenols, alcohols, carboxylic acids, esters, ethers, aldehydes, ketones, anhydrides and hydrocarbons. There was a predominance of hydrocarbons in the bio-oils of fiber, with no identification of ethers, anhydrides and aldehydes.

Characterization of bio-oils and bio-char obtained from the pyrolysis of a mixture of Lolium perenne, Festuca ovina, Festuca rubra and Poa pratensis grasses

ABSTRACTIn this work, the yield and chemical characterization of products obtained from the pyrolysis of a mixture of Lolium perenne, Festuca ovina, Festuca rubra and Poa pratensis grasses under an inert atmosphere at 600°C with a heating rate of 50°C/min was studied. Distribution of the products of pyrolysis grass sample was: moisture: 8 ± 2%, total volatiles: 78 ± 7%, char: 14 ± 5%. Bio-oils were acidic and dark brown liquids and they were separated into oils, asphaltenes and asphaltols by solvent extraction procedures prior to gas chromatography-mass spectrometry (GC-MS) analyses. GC-MS results showed that the bio-oils contained complex mixtures of organic compounds, including acetic acid and a large variety of oxygenated and nitrogenated compounds such as phenols, pyridines, pyrazoles, imidazoles, amines, and ketones. SEM micrographs of the bio-chars indicated amorphous, porous and heterogeneous structure of the bio-char obtained from the grass sample. EDX analysis of the bio-char revealed that bio-char contained K, Ca, P and Mg elements.

Production and chromatographic characterization of bio-oil from the pyrolysis of mango seed waste

Mango seed waste consists of tegument and almond and represents a considerable environmental problem in Brazil, due to the large amounts produced in the industrial processing of the fruit. An interesting alternative of utilising the mango seed waste is in the production of bio-oil by pyrolysis. The aim of this study was to produce bio-oil by pyrolysis of mango seed waste and observe its detailed chemical composition. The biomass, tegument and almond, were submitted to a pyrolysis in a fixed bed reactor at different final temperatures (450°C/550°C and 650°C). The higher bio-oil yield obtained for tegument was 38.8% at 650°C and for almond 28.1% at 450°C. The bio-oils detailed compositions were investigated using GC×GC/TOFMS allied to software tools, retention index and dispersion graphics. A total number of 108 and 120 compounds tentatively identified in tegument-bio-oil and almond-bio-oil, respectively were found. The chemical compositions in each bio-oil were different. The major classes were: phenols (32.6%) and ketones (22.9%) in tegument-bio-oil and ketones (20.6%), acids (16.8%) and hydrocarbons (7.2%) in almond bio-oil. This is the first time that bio-oil has been produced by pyrolysis of mango seed waste and these bio-oils showed potential for the production of chemical and liquid fuels, proving to be a good option for the destination of this waste.

Preparation and characterization of bio-oil by microwave pyrolysis of biomass

ABSTRACTA low temperature method was used to produce bio-oil from fir sawdust by means of microwave pyrolysis. Effects of reaction temperature, ratios of the microwave absorption medium to sawdust, and reaction time on the yield of bio-oil were investigated. The results show that an optimized yield of 21.22% is achieved. Bio-oil obtained was analyzed by gas chromatography-mass spectrometry and Fourier transform infrared, and the result reveals that the product mainly consists of phenolic compounds with esteric compounds as the minor components. Thermal weight loss curves of bio-oil were determined by thermogravimetry-differential thermal analysis in the oxygen atmosphere at different super-heating rates, and combustion kinetic parameters were calculated.

Characterization of bio-oils from the fast pyrolysis of white oak and sweetgum

Conversion of lignocellulosic biomass into bio-oil through fast pyrolysis process is considered one of the promising routes to supplement conventional fossil oil. Future bio-refineries require production large amounts of bio-oil from several biomass types. Characterization of the produced bio-oils is important to determine their suitability as bio-refinery feedstock. In this study, bio-oils were produced from white oak and sweetgum woods in an auger reactor at 450°C. The yields of char, liquid, and gas were calculated. The physical characterization of bio-oils was performed based on the investigation of different properties, such as pH, density, viscosity, water content, acid value, and molecular weight distribution of bio-oil components. The chemical compositions of the bio-oils were also investigated by gas chromatography/mass spectrometry and Fourier transform infra-red analyses. The physicochemical properties of the produced bio-oils were comparable to those obtained from similar woody biomass and the oils were suitable for fuel production.

Effect of Biomass Types on Bio-oil Characteristics in a Catalytic Fast Pyrolysis Process with a Ni/ZSM-5 Catalyst

Effect of Biomass Types on Bio-oil Characteristics in a Catalytic Fast Pyrolysis Process with a Ni/ZSM-5 Catalyst

Heat Generation during the Aging of Wood-Derived Fast-Pyrolysis Bio-oils

The changes in chemical composition and physical properties that accompany bio-oil aging reactions have been studied earlier. However, one fundamental aspect of this transformation process has been ignored. In this article, we prove that aging of fast-pyrolysis bio-oils from woody biomass is an exothermic process with notable heat generation under adiabatic conditions. The heat generation characteristics of several fast-pyrolysis bio-oils were studied in a novel reaction calorimeter that was made in-house. When typical fast-pyrolysis bio-oils were stored at 50 °C for a period of 1 week, they exhibited overall adiabatic temperature increases ranging from 14 K to 28 K. The largest differences in heat generation were observed at the beginning of the aging period, which corresponds with the previously known reactivity characteristics of bio-oils. Increasing the storage temperature accelerated the aging reactions, which manifested as higher overall temperature increases—up to 55 K in 1 week—and higher specific...

Analysis of Physicochemical Properties of Bio-Oil from Hydrothermal Liquefaction of Blackcurrant Pomace

Bio-oils obtained from hydrothermal liquefaction of biomass are black viscous fuels with good heating values. This paper presents results of physical and chemical characterization of bio-oils produced by hydrothermal liquefaction of blackcurrant pomace. The oils are analyzed with standard normalized tests and compared to specifications required by commercialized biofuels and conventional fuels. Iodine value and total acid number are determined, showing relatively high values. GC/MS analysis demonstrates that bio-oil recovery by solvent extraction followed by subsequent evaporation of the solvent leads to the loss of some volatile compounds in the bio-oil. Thermogravimetric analysis are performed to study the volatility of HTL bio-oils, as well as to evaluate the carbon residue after evaporation. The viscosity of a bio-oil recovered by ethyl-acetate extraction was measured with a rotational viscometer at 25 degrees C, leading to a viscosity of 1.7 Pa.s. The results show furthermore that adding sodium hydroxide to the reaction medium has a limited influence on the properties of bio-oils. The choice of extraction solvent has conversely a significant influence on the quality of the produced oil. We demonstrate in this paper how standardized tests can be applied to hydrothermal bio-oils, to compare them with commercial fuels and evaluate the need for upgrading.

Characterization of thermal and catalytic pyrolysis bio-oils by high-resolution techniques: 1H NMR, GC × GC-TOFMS and FT-ICR MS

Bio-oils of pine wood and sugarcane bagasse were obtained in different conditions of thermal and catalytic pyrolysis. They were analyzed by hydrogen nuclear magnetic resonance (1H NMR), comprehensive two-dimensional gas chromatography with time-of-flight mass spectrometry (GC×GC-TOFMS), and negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI(−)-FT-ICR MS) to provide a complementary and comprehensive characterization of the bio-oils. The elucidation of bio-oils composition is essential to assign the best application of bio-oils and the type of process required for upgrading methods. In general, the results obtained by 1H NMR and GC×GC-TOFMS showed a decrease of oxygen compounds (especially acids) and an increase of aromatic compounds when catalytic pyrolysis was used. The compound classes identified in each sample by GC×GC-TOFMS were acids, ketones, cyclic ketones, phenols, O-heterocyclic, and aromatic hydrocarbons. ESI(−)-FT-ICR MS provides relative signals and the bio-oil compounds containing hydroxyl or carboxylic acid groups, such as carboxylic acids and phenols, are selectively ionized. Via ESI(−)-FT-ICR MS, the oxygen-containing compounds determined in bio-oil samples were from O2–O12 classes, with the O4 being the major class. ESI(−)-FT-ICR MS results suggest that use of the ZSM-5 catalyst provides a decrease in the class abundance of higher oxygen atom number (>O5 classes), and consequently, the increase of lower oxygen atom number classes (O2–O4). The integrated results from these three high-resolution techniques were important to comprehensively assess the molecular composition of bio-oils. The 1H NMR provided the whole bio-oils composition profile assessment; GC×GC-TOFMS and ESI(−)-FT-ICR MS results allowed a detailed speciation of the chemical composition of bio-oils.

Bioslurry as a Fuel. 7: Spray Characteristics of Bio-Oil and Bioslurry via Impact and Twin-Fluid Atomizers

This study reports the spray characteristics of two fast pyrolysis bio-oils with different viscosities (0.0753 and 0.1522 Pa·s at 21 °C) and a set of bioslurry samples prepared from the bio-oils at various biochar loading levels (5, 10, 15, and 20 wt %). Two types of atomizers (impact atomizer and two-fluid atomizer) were used. Experiments for the impact atomizers of various sizes were carried out at injection pressures of 2.07–4.96 MPa and feeding rates of 108–490 mL/min. At a constant pressure, the Sauter mean diameter (SMD) of bio-oil and bioslurry increases as the flow number increases, while at a constant flow number, the SMD decreases rapidly with increasing pressure. The biochar loading level has a significant impact on the bioslurry atomization characteristics. An increase in biochar leading level results in a substantial increase in the spray SMD. Experiments using the twin-fluid atomizer (N2 as the atomization gas) were carried out at flow rates of 2–6 mL/min. A twin-fluid atomizer is more appli...

Bio-oil production of softwood and hardwood forest industry residues through fast and intermediate pyrolysis and its chromatographic characterization

Bio-oils were produced through intermediate (IP) and fast pyrolysis (FP), using Eucalyptus sp. (hardwood) and Picea abies (softwood), wood wastes produced in large scale in Pulp and Paper industries. Characterization of these bio-oils was made using GC/qMS and GC×GC/TOFMS. The use of GC×GC provided a broader characterization of bio-oils and it allowed tracing potential markers of hardwood bio-oil, such as dimethoxy-phenols, which might co-elute in 1D-GC. Catalytic FP increased the percentage of aromatic hydrocarbons in P. abies bio-oil, indicating its potential for fuel production. However, the presence of polyaromatic hydrocarbons (PAH) draws attention to the need of a proper management of pyrolysis process in order to avoid the production of toxic compounds and also to the importance of GC×GC/TOFMS use to avoid co-elutions and consequent inaccuracies related to identification and quantification associated with GC/qMS. Ketones and phenols were the major bio-oil compounds and they might be applied to polymer production.

Characteristics of bio-oil, bio-char production from lignocellulosic biomass under slow pyrolysis system

Characteristics of bio-oil, bio-char production from lignocellulosic biomass under slow pyrolysis system

Stabilization of Softwood-Derived Pyrolysis Oils for Continuous Bio-oil Hydroprocessing

The use of fast pyrolysis oil as a potential renewable liquid transportation fuel alternative to crude oil depends on successful catalytic upgrading to produce a refinery-ready product with oxygen content and qualities (i.e., specific functional group or compound content) compatible with the product’s proposed refinery insertion point. Similar to crude oil hydrotreating, catalytic upgrading of bio-oil requires high temperature and pressure. However, processing thermally unstable pyrolysis oil is not straightforward. For years, a two-temperature, downflow trickle bed reactor using sulfided catalysts was the state-of-the art for continuous operation. However, pressure excursion due to plug formation still occurred, typically at the high-temperature transition zone, and led to a process shutdown within 140 h. A plug typically consists of polymerized bio-oil and inorganic constituents that bind catalysts at specific portions preventing liquid and gas flow through the bed, resulting to a potential pressure incursion. Recently, two factors were found to enable continuous operation by preventing reactor shutdown due to plug formation: (1) a bio-oil pretreatment process prior to the two-temperature reactor, and (2) a robust commercial catalyst for the high temperature zone reactor. Here, we report the use and characterization of bio-oil that was pre-treated at 413 K and 8.4 MPa under flowing H2 (500 L H2/L bio-oil, 0.5 L bio-oil/L catalyst bed) to enable the long-term (cumulative 1440-h) bio-oil hydroprocessing.

Analysis of Bio-Oil Produced by Co-Pyrolysis of Mahua Seed and Polystyrene

TheProduction of biofuel from biomass sources is believed to reduce the reliance of fossil fuel and its cost. This investigation was aimed to produce and characterize the bio-oil obtained from co-pyrolysis. Two different feed stocks were used for co-pyrolysis; one is Mahua seed (MS) and the other one is Polystyrene (PS). The effect in addition of plastic to biomass in pyrolysis process were investigated on the yield and quality of products. Experiments were conducted in a semi-batch pyrolysis reactor under various parameters of temperature, heating rate and blending ratio. The results indicated that a temperature of 525 °C, and blend ratio of 1:1is maximumwith a heating rate of 20 °C/min. The yield of bio-oil obtained from the co-pyrolysis was found to be approximately 71%, which was higher about 22% than that of yield obtained from pyrolysis of Mahua seed (MS) alone. Further the bio-oil was characterized using different spectroscopic and chromatographic analyses. The analysis of the results for characterization of bio-oil indicated that the synergetic effect increased the bio-oil yield and its quality.

Characterization of bio-oils from the alkanolyses of sweet sorghum stalk by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

Bio-oils (BOs) obtained from sweet sorghum stalk (SSS) methanolysis (BOm) and ethanolysis (BOe) at 300°C for 30min were analyzed with an electrospray ionization Fourier transform ion cyclotron resonance mass spectrometer (ESI FT-ICR MS). In negative-ion mode, the predominant compounds in BOm and BOe are On (n=1–10) class species with double bond equivalent (DBE) values of 1–14 and carbon atom numbers (CANs) of 5–35. The most abundant class species in BOm and BOe are O4 and O3, respectively. According to the distribution of On class species and the van Krevelen diagram, lignin-derived compounds are the main acidic species in the BOs. In addition, N1On (n=0–10) class species with DBE values of 1–14 and CANs of 7–35 were also identified. In positive-ion mode, most of detected compounds in BOm and BOe are N2On (n=1–6) class species with DBE values of 1–19 and CANs of 10–40, in which N2O2–N2O4 class species with DBE=8–12 and CAN=19–28 are the most abundant. These results facilitate understanding thermochemical behavior of SSS.

Production and characterization of bio-oil and biochar from the pyrolysis of residual bacterial biomass from a polyhydroxyalkanoate production process

Polyhydroxyalkanoate (PHA) production generates a significant amount of residual bacterial biomass (RBB) after PHA extraction. The RBB as a zero-value waste contains proteins, carbohydrates, phenolics, and ash, which can be managed and converted to bio-oil and biochar products by pyrolysis. Thermogravimetric analysis (TGA) was used to investigate the thermodegradation kinetics of RBB and pyrolysis–GCMS studies were employed to determine potential chemical products. Pyrolysis was conducted on a laboratory-scale auger reactor at 500°C. The bio-oil and biochar yield were 28 and 46%, respectively. The pyrolysis bio-oil was characterized by the combination of GCMS, high-pressure liquid chromatography (HPLC), and electrospray ionization mass spectrometry (ESI–MS). The bio-oil was dominated by nitrogen-containing, hydrocarbons, and aromatic compounds. The biochar was studied for its specific surface area and pore size, chemical functionality by Fourier transform infrared (FTIR) and Raman spectroscopies, and butane absorption activity. Biochar was comprised of a large part of polycondensed phenolic and majorly disordered amorphous carbon.

Thermal and Storage Stability of Bio-Oil from Pyrolysis of Torrefied Wood

The objective of this paper is to investigate the biomass torrefaction effect on bio-oil stability by comparing the physicochemical and compositional properties of aged bio-oils. Two aging methods, accelerated aging (held at 80 °C for 24 h) and long-term natural aging (12-month storage at 25 °C), were employed to produce aged bio-oils for such comparison. The results indicate that bio-oils made from heat-treated wood had similar aging behavior in terms of increase of water content, acid content, molecular weight, and viscosity. The increase rate, however, was found to be different and dependent on the aging method. The accelerated method found parallel water and total acidity number (TAN) increments between raw and torrefaction bio-oils, while the natural aging method found torrefaction bio-oils, especially those made from heavily treated wood, had much slower water and acid accumulation than that of raw bio-oil. As a negative effect, both methods identified the viscosity of torrefaction bio-oils increased more significantly than that of raw bio-oil, while their molecular weights were unexpectedly lower. The correlation study showed that bio-oil viscosity is more tied to the content of bio-oil–water insoluble fraction rather than its average molecular weight. In addition, the characterization of aged bio-oils using NMR, GC/MS, and solvent fractionation indicated that torrefaction bio-oils had less compositional alternation after accelerated aging than the raw bio-oil. Also, they were more stable during the first 6 months of storage at room temperature. During the long-term storage, the raw bio-oil completely phase-separated after 6 months. However, two distinct torrefaction bio-oils (LP-280T and LP-330T) had enhanced phase stability, as a stable uniform oil phase without gum formation can be maintained during the entire 12-month storage.