Biomass-derived Oil Research Articles

Solvent-free synthesis of bio-based non-isocyanate polyurethane (NIPU) with robust adhesive property and resistance to low temperature

Non-isocyanate polyurethane (NIPU) adhesives represent a cutting-edge advancement in adhesive technology, poised to significantly diminish the dependency on isocyanate-based PU within the industry. In the context of the increasing scarcity of petroleum-based resources and the growing imperative for sustainable environmental practices, the pursuit of a comprehensively sustainable, bio-derived non-isocyanate polyurethane (NIPU) adhesive has swiftly become a pivotal area of interest within the scientific research community. In this study, the cashew phenol cyclic carbonate (CPCC) was synthesized through the addition polymerization process involving cashew phenol glycidyl ether (602A) with carbon dioxide (CO2), followed by a curing step utilizing a diamine extracted from biomass-derived oil to produce bio-based NIPU at ambient temperature. The synthesized NIPU adhesive demonstrated remarkable thermal stability and exceptional adhesion to a variety of substrate materials. Notably, the adhesive showcased superior bonding efficacy at ultra-low temperatures, with steel bonding strength reaching up to 7.78 MPa at −37 °C. This study presents an efficient and accelerated synthesis approach for the preparation of bio-based NIPU, offering a significant contribution to the field. Moreover, it provides a valuable reference for future advancements in NIPU adhesive technology, particularly for the applications requiring robust bonding at low-temperature environments.

Experimental investigation of optimum bio-oil production parameters through co-pyrolysis of three organic wastes

In Bangladesh, approximately 24,000 tonnes of general wastes are produced per day which creates environmental pollution due to lack of their proper disposal. Hence, a unique utilization of three types of wastes named rice husk (RH), scrap tire (ST) and low-density polyethylene (LDPE) has been investigated using a fixed bed co-pyrolysis reactor for bio-oil extraction. Pyrolysis is selected because it produces more liquid (bio-oil) than other thermochemical treatments. The extracted bio-oil has been characterized by elemental analysis, calorific value, fourier transform infrared spectroscopy (FTIR) and gas chromatography (GC-MS). During co-pyrolysis it is observed that higher process temperature produces more gaseous product and comparatively less char and liquid products (above 400 °C). In terms of a mixing ratio, higher percentage of LDPE produces more liquid and gaseous products on the contrary less amount of char product. The optimum operating conditions to produce maximum amount of bio-oil were 400 °C temperature for particle size of 1.18–2.36 mm, feed mixing ratio of 40:40:20 (ST/RH/LDPE), and running time of 120 min. The elemental analysis of the extracted bio-oil showed higher carbon and hydrogen content and lower oxygen content with a higher calorific value than that of the studied individual biomass-derived oil, leading to upgraded bio-oil. FTIR and GC-MS analysis clarifies the presence of mainly aliphatic compound in the co-pyrolytic oil. However, the number of aromatic compounds present in the co-pyrolytic oil is less than the individual biomass derived oil. The results indicated that the co-pyrolysis of ST, RH, and LDPE could be a promising way of organic waste material conversion into useful alternative fuel.

Combustion and emission characteristics of hydrotreated pyrolysis oil on a heavy-duty engine

Second-generation biofuel is promising to be applied in the field of long-haul transportation, aviation, and marine shipping. This work focuses on the ignition behavior, combustion process, and emission characteristics of hydrotreated pyrolysis oil. This biomass-derived oil was blended with marine gas oil from 10 to 30 wt% without a co-solvent or emulsifier. Tests were performed both on a combustion research unit and a commercial heavy-duty diesel engine setup. The results from the combustion research unit reveal that ignition delay increase as hydrotreated pyrolysis oil blend ratio increases at tested ambient conditions. Engine tests were first performed under factory settings at representative load/speed points based on the European stationary test cycle for benchmarking. Then start of injection and fuel pressure are varied to check the controllability and engine sensitivity of hydrotreated pyrolysis oil blends. It is shown that under engine conditions, the combustion characteristics and heat release are quite identical among hydrotreated pyrolysis oil blends and diesel. Though all cases present ultra-low particulate matter emissions, hydrotreated pyrolysis oil blends yield higher particulate matter emissions, which increase as the blend ratio increases. The particulate matter/NOx tradeoff is observed both for benchmarking tests and parameter study. The results indicate that the engine can run with HPO blends smoothly and safely without major modification.

Current and Future Trends for Crude Glycerol Upgrading to High Value-Added Products

Crude glycerol is the main byproduct of biodiesel manufacturing from oleaginous crops and other biomass-derived oils. Approximately 10% crude glycerol is produced with every batch of biodiesel. Worldwide, there is a glut of glycerol and the price of it has decreased considerably. There are real opportunities for valorizing crude glycerol into higher value-added chemicals which can improve the economic viability of biodiesel production as an alternative fuel. Exploring new potential applications of glycerol in various sectors is needed such as in pharmaceuticals, food and beverages, cosmetics, and as a transportation fuel. However, crude glycerol produced directly from biodiesel often contains impurities that hinder its direct industrial usage and thus, a refining process is needed which is typically expensive. Hence, this review reports on current upgrading crude glycerol technologies—thermo-, bio-, physico-, and electrochemical approaches—that valorize it into higher value-added chemicals. Through comparison between those viable upgrading techniques, future research directions, challenges, and advantages/disadvantage of the technologies are described. Electrochemical technology, which is still underdeveloped in this field, is highlighted, due to its simplicity, low maintenance cost, and it working in ambient condition, as it shows promising potential to be applied as a major glycerol upgrading technique.

Performance of Structural Alloys in Bio-oil Production, Upgrading, and Storage Systems

Selection of corrosion-resistant, cost-effective structural materials for the process and containment vessels required for the production, upgrading, and storage of biomass-derived oils has been the subject of study in our laboratory for many years. The wide variety of biomass resources and the many liquefaction techniques and processing conditions result in products with a broad range of properties and compositions. This paper will address the materials issues in three distinct areas. In production, materials are exposed to temperatures that range from 350 to 550 °C depending upon the process. Generally, austenitic stainless steels have performed reasonably well, although thicker oxide scales and intergranular attack have sometimes been observed. For storage and transport of the bio-oil products, temperatures experienced by the containment materials are not expected to exceed 50 °C. Our studies have shown that most raw bio-oils contain significant concentrations of organic acids, and low-molecular-weight organic acids were quite corrosive to carbon and low alloy steels. For some applications, subsequent processing is required, which includes hydrotreating or co-processing with a petroleum-derived liquid. These processes utilize a catalyst that requires periodic retreatment with a sulfidizing gas, and the exposure to this gas at elevated temperatures can cause appreciable corrosion to the more common austenitic stainless steels. The materials considered most cost-effective and sufficiently corrosion-resistant for each of these environments were identified.

Corrosion Compatibility of Stainless Steels and Nickel in Pyrolysis Biomass-Derived Oil at Elevated Storage Temperatures

Corrosion compatibility of stainless steels and nickel (Ni200) was assessed in fast pyrolysis bio-oil produced from pyrolysis of high ash and high moisture forest residue biomass. Sample mass change, ICP-MS and post-exposure electron microscopy characterization was used to investigate the extent of corrosion. Among the tested samples, type 430F and type 316 stainless steels (SS430F and SS316) and Ni200 (~98.5% Ni) showed minimal mass changes (less than 2 mg∙cm−2) after the bio-oil exposures at 50 and 80 °C for up to 168 h. SS304 was also considered to be compatible in the bio-oil due to its relatively low mass change (1.6 mg∙cm−2 or lower). SS410 samples showed greater mass loss values even after exposures at a relatively low temperature of 35 °C. Fe/Cr values from ICP-MS data implied that Cr enrichment in stainless steels would result in a protective oxide layer associated with corrosion resistance against the bio-oil. Post exposure characterization showed continuous and uniform Cr distribution in the surface oxide layer of SS430F, which showed a minimal mass change, but no oxide layer on a SS430 sample, which exhibited a significant mass loss.

Effect of Carboxylic Acids on Corrosion of Type 410 Stainless Steel in Pyrolysis Bio-Oil

Biomass-derived oils are renewable fuel sources and commodity products and are proposed to partially or entirely replace fossil fuels in sectors generally considered difficult to decarbonize such as aviation and maritime propulsion. Bio-oils contain a range of organic compounds with varying functional groups which can lead to polarity-driven phase separation and corrosion of containment materials during processing and storage. Polar compounds, such as organic acids and other oxygenates, are abundant in bio-oils and are considered corrosive to structural alloys, particularly to those with a low-Cr content. To study the corrosion effects of small carboxylic acids present in pyrolysis bio-oils, type 410 stainless steel (SS410) specimens were exposed in bio-oils with varying formic, acetic, propionic and hexanoic acid contents at 50 °C during 48 h exposures. The specific mass change data show a linear increase in mass loss with increasing formic acid concentration. Interestingly, a mild corrosion inhibition effect on the corrosion of SS410 specimens was observed with the addition of acetic, propionic and hexanoic acids in the bio-oil.

Sustainable production of bio-jet fuel and green gasoline from date palm seed oil via hydroprocessing over tantalum phosphate

The conversion of biomass into liquid fuels has gained worldwide attention because of its potential to reduce pollution. Drop-in biofuels are non-oxygenated liquid hydrocarbons that are produced from renewable biomass sources. These biofuels (that consist of biogasoline, bio-jet fuel, and green diesel fractions) hold a lot of promise owing to their properties that are similar to those of fossil fuels. In this work, the use of tantalum phosphate (TaPa) as a hydroprocessing catalyst for the drop-in biofuel production from date palm seed oil under mild experimental conditions was investigated. Mesoporous TaPa was intrinsically synthesized and comprehensively characterized using several analytical techniques. Further, the catalyst performance was investigated for its various dosages (0–15 wt%) under different reaction times (2–4 h) and temperatures (300–450 °C), using 10 bar H2. Infrared spectroscopy and Gas chromatography techniques were used to characterize and quantify the product oil composition, respectively. Optimization of the proposed one-step reaction approach resulted in high yields of deoxygenated hydrocarbons that consisted of 53.6% of bio-jet fuel (C9-C15) and 35.9% of green diesel (C14-C20) fractions. The plausible pathways for the formation reactions of various linear and branched aliphatics and aromatics in the product oil are discussed. Besides, the reusability of the TaPa for continuous hydroprocessing of the bio-oil was demonstrated. Thus, the production of bio-jet fuel and green diesel using the date palm seed biomass-derived oil in the presence of TaPa catalyst is sustainable, efficient, safe, and has great potential for aviation applications.

Friction and wear properties of biomass-derived oils via thermochemical conversion processes

Tribological properties of biomass-derived oils (bio-oils) were experimentally investigated, and the properties were compared with that of standard mineral oils used for lubrication purposes. Bio-oils were obtained from fast pyrolysis (using poultry and pine), gasification (“gasitar” using pine) and hydrothermal liquefaction processes (using Scenedesmus and Nannocholoropsis). The friction and wear tests were conducted using a ball on the disk tribometer test. The results showed that the coefficient of friction (COF) were around 0.02 for both gasitar and Scenedesmus bio-oil; whereas, catalytic and non-catalytic pyrolysis oils had a COF around 0.1. The wear measurements showed that catalytic fast pyrolysis bio-oils had lower wear followed by non-catalytic bio-oil and “gasitar”. Nannocholoropsis bio-oil had the highest amount of wear, and algal bio-oils showed higher wear compared to other oils. The bio-oil chemical analysis indicated that catalytic and non-catalytic fast pyrolysis bio-oil had higher oxygen content, while algal bio-oil had higher nitrogenates. Gasitar had higher hydrocarbon content with lower oxygen and nitrogenates making it a favorable lubricating oil.

Recent Catalytic Advances in Hydrotreatment Processes of Pyrolysis Bio-Oil

Catalytic hydrotreatment (HT) is one of the most important refining steps in the actual petroleum-based refineries for the production of fuels and chemicals, and it will play also a crucial role for the development of biomass-based refineries. In fact, the utilization of HT processes for the upgrading of biomass and/or lignocellulosic residues aimed to the production of synthetic fuels and chemical intermediates represents a reliable strategy to reduce both carbon dioxide emissions and fossil fuels dependence. At this regard, the catalytic hydrotreatment of oils obtained from either thermochemical (e.g., pyrolysis) or physical (e.g., vegetable seeds pressing) processes allows to convert biomass-derived oils into a biofuel with properties very similar to conventional ones (so-called drop-in biofuels). Similarly, catalytic hydro-processing also may have a key role in the valorization of other biorefinery streams, such as lignocellulose, for the production of high-added value chemicals. This review is focused on recent hydrotreatment developments aimed to stabilizing the pyrolytic oil from biomasses. A particular emphasis is devoted on the catalyst formulation, reaction pathways, and technologies.

Heterogeneous ketonic decarboxylation of dodecanoic acid: studying reaction parameters.

Ketonic decarboxylation has gained significant attention in recent years as a pathway to reduce the oxygen content within biomass-derived oils, and to produce sustainable ketones. The reaction is base catalysed, with MgO an economic, accessible and highly basic heterogeneous catalyst. Here we use MgO to catalyse the ketonic decarboxylation of dodecanoic acid to form 12-tricosanone at moderate temperatures (250 °C, 280 °C and 300 °C) with low catalyst loads of 1% (w/w), 3% (w/w) and 5% (w/w) with respect to the dodecanoic acid, with a reaction time of 1 hour under batch conditions. Three different particle sizes for the MgO were tested (50 nm, 100 nm and 44 μm). Ketone yield was found to increase with increasing reaction temperature, reaching approximately 75% yield for all the samples tested. Temperature was found to be the main control on reaction yield, rather than surface area or particle size.

Silica-Supported Fe(II), Co(II) and Ni(II) Complexes as Efficient Catalysts to Esterification of Levulinic acid with Polyol

Biomass-derived feedstocks were used to synthesize a new polyol-based ester for biolubricant production to overcome the dependence on mineral oil. Although biomass-derived oil is a potential alternative to polyol ester, upgrading is inevitable before using it as a biolubricant. Levulinic acid (model acid), obtained from a bio oil, was used for the esterification of two polyols, for example, neopentyl glycol (NPG) and trimethylolpropane (TMP), in the presence of ligand metal Fe(II), Co(II), and Ni(II) complexes as catalyst. Silica-supported Fe(II), Co(II) and Ni(II) complexes viz. [Fe(Tyr)(Amp)]Cl·SiO2, [Co(Phe)(Bpy)]Cl·SiO2 and [Ni(Leu)(Phen)]Cl·SiO2 were synthesized by the reaction of ligands [L-phenylalanine (Phe), L-tyrosine (Tyr), L-leucine (Leu), 4,4′-bipyridine (Bpy), 2-aminopyridine (Amp) and 1,10-phenanthroline (Phen)] with respective metal(II) chloride salts. All the metal complexes were characterized by elemental analysis, magnetic susceptibility, TGA/DTA, FTIR, powder-XRD and SEM methods. The catalytic activities of the complexes were further investigated via esterification of two polyols (e.g. neopentyl glycol and trimethylolpropane) by biomass-derived levulinic acid (LA). Herein, iron(II) complex was found to be more active, demonstrating its better efficiency as a catalyst towards the esterification of levulinic acid for synthesizing ester-based oils.

Exploring the Reaction Mechanisms of Furfural Hydrodeoxygenation on a CuNiCu(111) Bimetallic Catalyst Surface from Computation.

In this study, the selectively catalytic hydrodeoxygenation of furfural (F–CHO) to 2-methylfuran (F–CH3) on the CuNiCu(111) bimetallic catalyst surface was systematically investigated based on the periodic density functional theory, including dispersion correction. The formation of furfuryl alcohol (F–CH2OH) involved two steps: the preferred first step was the hydrogenation of the branched C atom, forming the alkoxyl intermediate (F–CHO + H = F–CH2O), and the second step was H addition to the alkoxyl group, resulting in furfuryl alcohol (F–CH2O + H = F–CH2OH), which was the rate-controlling step. In contrast, in the formation of 2-methylfuran, the first step was the dehydroxylation of furfuryl alcohol, resulting in alkyl (F–CH2) and OH (F–CH2OH = F–CH2 + OH) groups, the second step was the hydrogenation of F–CH2 (F–CH2 + OH + H = F–CH3 + OH), and the rate-controlling step was the hydrogenation of OH to H2O (OH + H = H2O). Based on the comparison results of the NiCuCu(111), Cu(111), and CuNiCu(111) surfaces, it was concluded that the catalytic performance of the catalyst was closely related to the adsorption structure of furfural. These results provide a basis for studying the intrinsic activity of NiCu catalysts during the hydrodeoxygenation of refined oxygenated compounds involving biomass-derived oils.

Approaches to investigate the role of chelation in the corrosivity of biomass-derived oils

The need to provide the U.S. market with a renewable liquid fuel energy source from a non-food feedstock stream has gained considerable traction due to benefits such as improved energy efficiency, reduced environmental impacts, and enhanced national security. Practical achievement of these goals via biomass and bio-waste utilization involves production of liquid intermediates containing corrosive, reactive species like carboxylic acids, ketones, aldehydes, and hydroxyaldehydes. Such mixtures challenge materials of containment, processing, and transport. It is widely recognized that the smaller organic acids, such as acetic and formic, are corrosive and can remove protective surface oxides on alloys used in bio-oil processing infrastructure, and ketones can swell sealing polymers. However, literature shows, and findings herein confirm, larger carboxylic acids and bidentate alcohols are present. This highlights the potential for synergistic, detrimental effects of constituents in bio-oil corrosion, including direct reactivity of small acids compounded with the possibility of mobilization of protective metal oxide layers via chelation by larger acids and oxygenates. The question of whether species beyond small acids can significantly contribute to corrosion requires analytical approaches previously not applied to bio-oil corrosion studies and certainly not previously applied corroboratively. This work introduces a combination of optical, mass spectral, and electrochemical impedance spectroscopies with an incubation approach to study metal mobilization, to facilitate elucidating chelation's role in bio-oil corrosive pathways. To enable systematic study of these oxygenates' material compatibility individually and in combination, a model matrix of bio-oil constituents was also developed based on identification of key components of real bio-oils.

Ni, Zn and Fe hydrotalcite-like catalysts for catalytic biomass compound into green biofuel

Abstract In this study, the deoxygenation pathway was proposed to eliminate oxygen species from biomass-derived oil, thereby producing a high quality of hydrocarbon chains (green fuel). The catalytic deoxygenation reaction of bio-oil model compound (oleic acid) successfully produced green gasoline (C8–C12) and diesel (C13–C20) via activated hydrotalcite-derived catalysts (i.e. CMgAl, CFeAl, CZnAl and CNiAl). The reaction was performed under inert N2 condition at 300 °C for 3 h, and the liquid products were analysed by GC–MS and GC–FID analyses to determine the hydrocarbon yield and product selectivity. The activity of the catalysts towards the deoxygenation reaction presented the following increasing order: CNiAl > CMgAl > CZnAl > CFeAl. CNiAl produced a hydrocarbon yield of up to 89 %. CNiAl demonstrated the highest selectivity with 83 % diesel production, whereas CMgAl showed the highest gasoline selectivity with 30 %. These results indicated that catalysts with a high acidic profile facilitate C–O cleavage via deoxygenation, producing hydrocarbons (mainly diesel-range hydrocarbons). Meanwhile, highly basic catalysts exhibit significant selectivity towards gasoline-range hydrocarbons via cracking and lead to the occurrence of C–C cleavage. The large surface area of CNiAl (117 m2 g−1) offered high approachability of the reactant with the catalyst’s active sites, thereby promoting high hydrocarbon yield. Consequently, the hydrocarbon yield and selectivity of the deoxygenation products were predominantly influenced by the acid–base properties and structural behaviour (porosity and surface area) of the catalyst.

Hydro-processing of biomass-derived oil into straight-chain alkanes

Initially converting the glyceride-based oils derived from biomass into straight-chain alkanes are necessary for producing hydro-processed renewable jet (HRJ). In this study, palm oil was turned into C15–C18 alkanes over two different catalysts, Pd/C and NiMo/γ-Al2O3, with various reaction conditions such as temperature, pressure, weight hourly space velocity (WHSV) and H2-to-oil ratio. The fresh and used catalysts after hydro-processing reaction were then characterized through the techniques including TGA, FTIR, XRD and SEM. The liquid products were analysed through GC-MS/FID and the concentrations of C15–C18 were determined. The gas products, such as CO2, CO, C3H8, CH4 and H2, were analysed through GC-TCD for indirectly “visualizing” the reaction, including the performances of hydro-deoxygenation (HDO) as well as decarbonylation/decarboxylation, hydrogenolysis, the occurrence of methanation and the consumption of hydrogen. The suggested experimental conditions over these two catalysts were elaborated based on the concentration of n-alkanes and gas products.

Theoretical Study of the Mechanism of Furfural Conversion on the NiCuCu(111) Surface.

The full potential energy surface for the hydrodeoxygenation of furfural to furan and other ring-opening products has been systematically investigated using periodic density functional theory including dispersion corrections (PBE-D3) on the bimetallic NiCuCu(111) surface. For furan formation, the most favorable first step is the dehydrogenation of furfural into furoyl (F-CHO + H = F-CO + 2H), the successive step is decarbonylation of furoyl into furanyl (F-CO + H = F + CO + 2H), and the third step of furan formation from the hydrogenation of furanyl (F + CO + 2H = FA + CO + H) is the rate-determining step. In addition, on the basis of the most stably adsorbed furan and H, the ring opening of furan was found to be more favorable for producing many chemicals such as propane, butanal, butanol, and butene. In summary, furan is the main product of furfural conversion on the NiCuCu(111) surface. Since results have been obtained only for the NiCuCu(111) surface constructed by replacing the topmost Cu atoms by Ni atoms, the entire experimentally observed reactivity and selectivity of bimetallic CuNi catalysts for different construction methods cannot be fully rationalized. Nevertheless, the results provide the basis for investigating the intrinsic activity of CuNi catalysts in the hydrodeoxygenation of oxygenates involved in the refining of biomass-derived oils.

Changes in oxygen functionality of soluble portions and residues from bagasse sub- and supercritical alkanolyses: Identification of complex structural fragments

The changes in oxygen functionality of soluble portions and residues from the bagasse methanolysis (BM) and bagasse ethanolysis (BE) at 220, 240, 260, 280, and 300 °C were investigated. The highest yields of soluble portions, 40.8 wt% from BM and 48.1 wt% from BE, can be obtained at 280 °C for 0.5 h. The organic oxygen species evolution of the bagasse and residues were analyzed with Fourier transform infrared spectrometer, thermogravimetric analyzer, and X-ray photoelectron spectrometer. The results show that the contents of oxygen functional moieties between bagasse and residues are significantly different. The cleavage of >Cal-X bonds (X denotes Cal<, O-, N<, and/or S-), especially > Cal-Cal< and >Cal-O- bonds, should be the major reactions during the bagasse alkanolyses. In addition, based on the analysis with a gas chromatograph/mass spectrometer, oxygen-containing organic compounds produced from BM and BE can be divided into alkanols, alkenols, furans & tetrahydrofurans, alkyl-substituted phenols & benzenepolyols, methoxy-substituted benzenes, alkoxy-substituted phenols, benzaldehydes, ketones, esters, carboxylic acids, and other oxygenates. The depolymerization of cellulose and/or hemicellulose to pentose/hexose and/or other small-molecule products could facilitate the formation of cyclopentanones and cyclopent-2-enones. The comparison of the specific methyl and ethyl esters obtained from BM and BE, respectively, confirmed that the 4-hydroxyphenyl, 4-methoxyphenyl, guaiacyl, and/or syringyl units are likely present in the bagasse skeleton. Comparing the organic oxygen transformation during the bagasse alkanolyses will facilitate the utilization of oxygenated chemicals in the biomass-derived oils.

Co-pyrolysis of biomass and lignite: synergy effect on product yield and distribution

The pyrolysis of pistacia khinjuk seed (PS) lignite and their mixtures were investigated in a two different reactor with varying temperatures ranging from 400 to 700°C at a heating rate either 10 or 500°Cmin‒1, and different percentage of lignite. The maximum liquid product yield for PS/lignite co-pyrolysis was 60.7% at 5% lignite, pyrolysis temperature of 500°C and heating rate of 500°Cmin‒1 in the well-swept fixed bed reactor (WSR). However, the results indicated that the maximum synergetic effects were observed at 15% lignite and the amount of pyrolytic oil increased by (w/w) 10.1% at this optimum point. There is a significant increase in the amount of asphaltene and aromatic compounds for the co-pyrolytic oil. As a result, the pyrolytic oil improved at co-pyrolysis and the pyrolytic oil could be used for fuels and chemicals feedstock. Paper's highlights are: synergetic effect between biomass with lignite in co-pyrolysis process was clarified; the influence of the reactor configuration and blending ratio on the synergetic effect has been established; the co-pyrolysis process improved the quantity and quality of pyrolysis oil; blending with lignite led to a higher asphaltenes and aromatic ratio; and biomass-derived oil can be upgraded via co-pyrolysis of biomass with lignite. [Received: August 27, 2018; Accepted: January 29, 2019]

Processes for producing biomass-derived pyrolysis oils

Processes for producing biomass-derived pyrolysis oils