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Fast pyrolysis of biomass is crucial for sustainable biofuel production, necessitating thorough characterization of feedstocks to optimize thermal conversion technologies. This study investigated the isothermal pyrolysis of bamboo and pinewood biomass in a sand-fluidized bed reactor, aiming to assess biomass suitability for commercial bio-oil production. The pyrolysis products and biomass species were characterized through proximate and ultimate analyses, along with GCMS, FTIR, SEM/EDX, and structural analysis to assess their chemical and physical properties. Results indicated that pine bio-oil possesses superior energy density, with a higher calorific value (20.38 MJ/kg) compared to bamboo (18.70 MJ/kg). Pine biomass yielded greater organic phase bio-oil (BOP) at 13 wt%, while bamboo produced 9 wt%. Energy yields were also notable, with pine exhibiting an energy yield of 15% for bio-oil organic phase (EBOP), compared to 11% for bamboo. The fibrous nature of bamboo biomass resulted in less-reacted biomass at constant reaction time due to flow resistance during pyrolysis. Pine bio-oil organic phase (P-BOP) demonstrated a higher heating value (23.90 MJ/kg) than bamboo (B-BOP). The findings suggest that while both biomass types are viable renewable energy sources, pine biomass is more favorable for commercialization due to its superior energy properties and efficiency in pyrolysis. [ABSTRACT FROM AUTHOR]

Recently, pyrolysis has raised great interest due to its high potential for yield high-quality bio-oil and value-added chemical production with the ability to be used as renewable energy, and/or for the production of high value-added chemical compounds. The chemical compounds produced and their quantities are entirely related to the characteristics and chemical composition of the precursor biomass and fast pyrolysis process conditions. In this work, Dendrocalamus asper biomass was performed using fast pyrolysis coupled to gas chromatography with mass spectrometry detector (Py-GC-MS). The non-wood biomass was characterized according to its chemical composition by determination and elemental composition. The biomass chemical composition have shown cellulose content (46.4%), hemicellulose content (14.9%), and Klason lignin content (18.9%). In addition, elemental composition demonstrated percentages of carbon (48.4%), oxygen (42.4%), and hydrogen (6.1%). In relation to carbohydrates, Py-GC-MS analyses showed the formation of several compounds of interest, such as acetic acid and, in smaller amounts, syringol, isoeugenol, and levoglucosan. On the other hand, the major compound found was 2,3-dihydrobenzofuran (~128 kg/ton), which is a high value-added chemical compound for pharmacy industry. Several studies have demonstrated the potential of this 2,3-dihydrobenzofurans for pharmacological use, such as anti-tumor, anti-cancer, anti-tubercular, anti-malarial, anti-bacterial, anti-oxidant, and anti-viral activities. The techno-economic assessment showed that 2,3-dihydrobenzofuran has a high market price (6977.68 US$/ton), and that a single-batch production will lead to a positive techno-economic balance, with high-potential profitable business. Finally, the present study offers an effective and eco-friendly method for processing agroindustrial waste, which enables the 2,3-dihydrobenzofurans with high yield and quality. [ABSTRACT FROM AUTHOR]

Biomass, as a renewable energy source, features wide availability, multiple functions, and carbon neutralization. The high-value resource utilization of biomass is conducive to reducing reliance on high-carbon fossil energy, ensuring national energy security, and curbing environmental pollution, aligning with the needs of China's "dual carbon" national strategy. Pyrolysis, as the foundation of biomass thermochemical conversion, is one of the best technologies to achieve a high-value utilization of biomass energy. However, it has some core issues such as low bio-oil yield and poor quality. To overcome these problems, a cryogenic technology was innovatively applied to the field of biomass pyrolysis, and a new biomass oil production method of "cryogenic + fast pyrolysis" was proposed to increase the yield and quality of pyrolytic bio-oil. Taking two types of crop straw as experimental research objects, the rapid freezing pretreatment method with liquid nitrogen was adopted to study the evolution mechanism of the product distribution and composition of biomass pyrolysis under cryogenic pretreatment. The experiments show that compared with conventional pyrolysis, the increase in the bio-oil yield after cryogenic pretreatment of biomass pyrolysis can reach 14.16% to 23.73%, and the cryogenic pretreatment temperature has a positive correlation with the bio-oil yield, and the maximum bio-oil yield (22.3% to 26.3%) is reached at −90 ℃, exceeding the bio-oil yield of the aluminum method by 8.50% to 22.71%. The cryogenic pretreatment has a significant transformation effect on the composition of the bio-oil, and the content of benzene series (BTEX) and phenolic substances in the bio-oil composition increases significantly, with the maximum increase of 43.61% and 12.45%, respectively. The cryogenic pretreatment of liquid nitrogen inhibited the release of CO2 and CO in biomass pyrolysis gas, and the proportion of components decreased by 7.2%−29.7%. In addition, the inhibition of the release of CO2 and CO in the biomass pyrolysis gas and the increase of CH4 and H2 by cryogenic pretreatment increase by 0.2% to 14.7%. Moreover, the increase in C content and the decrease in O content in the solid product under cryogenic pretreatment are conducive to improving the combustibility of biochar and reducing its risk of spontaneous combustion.

Biomass fast pyrolysis and in line Steam Reforming (SR) is a potential alternative to produce hydrogen. The addition of a sorbent such as CaO in the reforming process allows capturing in situ the CO 2 produced and shifting the equilibrium of the reactions involved towards the products, thus leading to higher H 2 production and purity. A thermodynamic equilibrium analysis by means of Gibbs free energy minimization method was performed to delimit the range of best operating conditions and assess the impact of Sorption Enhanced Steam Reforming (SESR) strategy on hydrogen production and purity, as well as on reaction enthalpy. A wide range of reforming operating conditions were studied with respect to temperature (300–800 °C) and Steam/Biomass (S/B) ratio (0–4), and the conventional SR was compared with the SESR processes. The SESR simulations were developed by adding the stoichiometric amount of calcium oxide (sorbent) required to capture all the CO 2 produced when full conversion of the volatile stream was attained in the SR process. In the SESR, a H 2 production of around 12.4 wt % (by mass unit of the biomass in the feed) and a H 2 purity higher than 98 vol % were obtained at temperatures in the 400–600 °C range and S/B ratios in the 1.5–3 range. In the SR, a H 2 production close to 11.8 wt % and a purity of 67.3 vol % was attained in the 550–650 °C range with a S/B ratio of 4. The SESR allows operating at lower temperatures and S/B ratios, thereby reducing energy requirements and, at the same time, attaining better performance than the conventional SR in terms of H 2 production and purity. [Display omitted] • Gibbs free energy minimization method was used for SESR and SR simulation. • SESR obtains higher H2 yield and purity at lower temperatures and S/B ratios. • In SESR, H2 yield (12.4 wt%) is maximum within 400–600 °C and 1.5–3 S/B ratios. • SESR requires less energy than SR as CO2 capture makes the process more exothermic. • The results obtained evidence the interest of in line pyrolysis-SESR strategy. [ABSTRACT FROM AUTHOR]

Thermochemical conversion of giant reed biomass during periodic variations has been carried out in a semi‐batch tubular reactor at 550°C. This study was carried out after the incineration of giant reed along the river banks. Four periodic variations, late spring (HS‐4), late summer (HS‐1), late autumn (HS‐2), and late winter (HS‐3) were considered to investigate the effect of harvest time on biomass fuel properties, pyrolysis product distribution, non‐condensable gas characterization, and bio‐oil organic phase (BOP) fuel properties. The considered biomasses herein had average calorific values of 18.86 ± 0.05, 19.73 ± 0.05, 19.23 ± 0.04, and 18.44 ± 0.04 MJ/kg during HS‐1, HS‐2, HS‐3, and HS‐4, respectively. The biomass, bio‐oil organic phase, biochar, and pyrolysis gas were characterized using thermogravimetric analysis (TGA), gas chromatography–mass spectroscopy (GCMS), Fourier transform infrared spectroscopy (FTIR), micro‐GC, and scanning electron microscopy (SEM/EDS). The organic phase of bio‐oil was isolated using a 125 mL separating funnel, allowing natural stratification of the immiscible phases. BOP yield increased from 5 to 11 wt% during HS‐4 and HS‐3, respectively. Higher heating values (HHV) of the BOP ranged from 19.4 ± 0.03 to 22.6 ± 0.02 MJ/kg in relation to the active growth stage and senescence‐dormant phase. Physical and chemical properties (TAN, density, viscosity, water content, and CHNS) and chemical compound groups of organic phase bio‐oil were analyzed. The produced BOP was rich in phenolics for all considered periods. The effect of harvest time showed that biomass and bio‐oil organic phase fuel properties are improved during the senescence‐dormant period. As a result, giant reed biomass should be harvested during autumn to avoid incineration that releases carbon dioxide into the atmosphere and will also reduce the occurrence of artificial flooding. [ABSTRACT FROM AUTHOR]

Fast pyrolysis of pre-treated birch wood in a super-heated steam environment produces a condensate rich in anhydrosugars. With the objective to obtain several product streams from this condensate, the possibility of extracting additional chemical species is explored, thus promoting the development of a pyrolysis-based biorefinery. In this work, the extraction and recovery of pyrolytic phenols from birch wood pyrolysis condensate was studied using ion exchange resins. With an aim to achieve effective phenol recovery, while obtaining high purity levoglucosan, basic ion exchange resins, both in OH− and Cl− form, as well as polystyrene-divinyl resins without functional groups were compared. This study characterizes the influence of sorbent matrix type and porosity, functional group and counter ion on the sorption of various aromatic compounds. It was concluded that the counter ion of the ion exchange resins had the most influence on the pyrolytic phenol adsorption, while in the case of unfunctionalized resins smaller pore size improved removal of phenols from the pyrolysis liquids. Of the resins tested, the most effective at the removal and recovery of pyrolytic phenols were strongly basic, macroporous, anion exchange resins in OH− form. The possibility to reuse the sorbents and solvents is explored to make the over-all process more environmentally friendly and economically feasible. [ABSTRACT FROM AUTHOR]

This study investigated the fast pyrolysis of biomass in fluidized-bed reactors using computational fluid dynamics (CFD) with an Eulerian multifluid approach. A detailed analysis was conducted on the influence of various modeling parameters, including hydrodynamic models, heat transfer correlations, and chemical kinetics, on the product yield. The simulation framework integrated 2D and 3D geometrical setups, with numerical experiments performed using OpenFOAM v11 and ANSYS Fluent v18.1 for cross-validation. While yield predictions exhibited limited sensitivity to drag and thermal models (with differences of less than 3% across configurations and computational codes), the results underline the paramount role of chemical kinetics in determining the distribution of bio-oil (TAR), biochar (CHAR), and syngas (GAS). Simplified kinetic schemes consistently underestimated TAR yields by up to 20% and overestimated CHAR and GAS yields compared to experimental data (which is shown for different biomass compositions and different operating conditions) and can be significantly improved by redefining the reaction scheme. Refined kinetic parameters improved TAR yield predictions to within 5% of experimental values while reducing discrepancies in GAS and CHAR outputs. These findings underscore the necessity of precise kinetic modeling to enhance the predictive accuracy of pyrolysis simulations. [ABSTRACT FROM AUTHOR]

Biomass, as a renewable and clean energy source, can be utilized for partial fuel substitution through the process of fast pyrolysis, which converts it into bio-oil. However, the presence of naturally occurring metallic elements in biomass has an adverse effect on its pyrolysis process. In this study, the aqueous fraction separated from biomass pyrolysis liquid, characterized by its acidity and high water content, was used for washing pretreatment of walnut shells. The analysis of the treated walnut shells was meticulously conducted employing techniques, including inductively coupled plasma mass spectrometry, thermogravimetric analyzer, and pyrolyzer-gas chromatography/mass spectrometer. The results indicate that this method has a positive influence on the composition and structure of walnut shells, with removal rates of 75% for Na and 45% for K. The thermal decomposition peak on the thermogravimetric curve became more distinct and shifted to higher temperatures. In additionally, the maximum weight loss rate increases to 0.83 °C/%, and the final residue decreased to 17%. The yields of acids and ketones in the pyrolysis products decreased by 49.43% and 53.69%, respectively. Meanwhile, the yields of phenols and sugars increased by 17.43% and 80%, respectively. Furthermore, the influence of pyrolysis conditions (temperature and time) on the pyrolysis products was investigated, and the optimal pyrolysis conditions (500 °C and 20 s) were determined. Therefore, washing pretreatment of the aqueous part of pyrolysis liquid can effectively enhance the quality of biomass and pyrolysis products. It not only contributes to improving the utilization value of pyrolysis liquid by-product but also holds practical significance for the sustainable use of resources and energy production. [ABSTRACT FROM AUTHOR]

Lately, pyrolysis has attracted significant attention due to its substantial potential for bio-oil production, with the ability to serve as a renewable energy source and/or facilitate the production of valuable chemical compounds. The chemical compounds generated and their amounts are completely influenced by the traits and chemical makeup of the initial biomass. In this work, the catalytic fast pyrolysis of Eucalyptus urograndis canopy was carried out using a pyrolyzer coupled to gas chromatography/mass spectrometry (Py-GC/MS) at different temperatures and in the presence and absence of catalysts. Elemental composition analysis was employed to characterize the chemical composition of the biomass. The results showed a biomass with a carbon percentage of 50.20%, oxygen of 43.21%, and hydrogen of 6.34%, as well as a lower calorific power of 17.51 MJ/kg. The Py-GC/MS analyses revealed the presence of several noteworthy compounds, including acetic acid (C2H4O2) and, in smaller quantities, hydrogen (H2), furfural (C5H4O2), and levoglucosan (C6H10O5). The technical-economic evaluation revealed that the production of acetic acid, furfural, hydrogen, and levoglucosan commands a high market price. Additionally, a single production cycle is anticipated to yield a favorable technical-economic balance, generating approximately USD 466.10 /ton of processed biomass. This outcome is achieved through the process of catalytic fast pyrolysis, where CuO has been identified as the most suitable catalyst. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Climate change demands urgent action to limit greenhouse gas (GHG) emissions and explore methods for atmospheric carbon removal. Forest residues, a significant biomass resource, represent a readily available solution. With the use of life cycle assessment (LCA), this study investigates the environmental advantages of thermochemical processes utilizing forest residues to produce valuable energy-dense products, like syngas, bio-oil, and biochar, providing a carbon sink. While slow pyrolysis emphasizes biochar production for carbon sequestration, gasification focuses on bioenergy generation. This research evaluates the environmental performance of both techniques in terms of carbon sequestration and GHG emissions mitigation. This comprehensive analysis aims to identify critical factors influencing the environmental sustainability of thermochemical processes in forest management. The findings aim to contribute to achieving sustainable development goals by highlighting the environmental advantages of biochar in mitigating climate change. [ABSTRACT FROM AUTHOR]

Technologies for producing renewable fuels and chemicals rely on the production of stable intermediates. For thermochemical technologies, pyrolysis of biomass produces oils that must compromise between carbon yield and oil quality. Bio-oil extraction has largely focused on regular bio-oils (~ 33 wt% O) and partially deoxygenated oils (< 12 wt% O). Furthermore, it is desired to extract phenolics without direct distillation of bio-oils, which would enable extraction from the heaviest portion of bio-oil. Mid-level oxygen (MLO) bio-oils (16–25 wt% O) produced from switchgrass were characterized for their ability to separate into phenolic-rich fractions. Toluene-soluble portions of the oils underwent NaOH extraction to extract one-ring phenolics, while toluene-insoluble portions were fractionated with iso-propyl alcohol (IPA). While phenolic extraction proceeded without distillation (having been a prerequisite for partially deoxygenated bio-oils), the efficiency of extraction was less than optimal, owing to the presence of other oxygenated compounds in the hydrocarbon-rich fraction. Both IPA-insoluble and IPA-soluble fractions underwent solvent liquefaction reactions with base additives. While using water as a reaction medium produced greater concentrations of phenols than when using methanol, addition of sodium carbonate produced narrower product distributions of phenols and inhibited formation of benzenediols. [ABSTRACT FROM AUTHOR]

Char gasification is a feasible technology to recycle CO2 and utilize biomass energy. However, the impact of different species of biomass on the gasification is still unclear. For the assessment of the feedstock effect on CO2 gasification, the present work prepared over 40 different wood char samples on a high temperature (around 1523 K) flame reactor, which simulate the rapid heating rates experienced in industrial reactors. Then, the curves of conversion (X) and conversion rate (dX/dt) versus temperature, and the conversion rate versus fractional conversion were derived from the linear non-isothermal thermogravimetric analysis. Three models (volumetric model, grain model, and random pore model) are examined for their goodness of fit between the model and experimental data, and their estimated activation energy. Finally, links between different biomass property parameters and different reactivity indexes were investigated. The results obtained show that different feedstocks result in different gasification reactivities of the resultant chars, with T50 and Tmax varying in a wide range of about 170 K and 200 K. But when conversion is plotted against dimensionless temperature, regardless of the feedstock origin, all the experimental plots can be described by only one curve for X = 0.2–0.95. We attributed the slightly superior prediction of the RPM to the increased amount of adjustable kinetic parameters, but lower E values were obtained by using RPM. In addition to the potassium content, the cellulose and lignin contents of the feedstock were found to have relatively high correlation with the char reactivity indexes. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the pyrolysis of selected California foliage and estimate the energy content of the released volatiles to show the significance of the pyrolysis of foliage and its role during wildland fires. While the majority of the volatiles released during the pyrolysis of foliage later combust and promote fire propagation, studies on the energy released from combustion of these compounds are scarce. Samples of chamise (Adenostoma fasciculatum), Eastwood's manzanita (Arctostaphylos glandulosa), scrub oak (Quercus berberidifolia), hoaryleaf ceanothus (Ceanothus crassifolius), all native to southern California, and sparkleberry (Vaccinium arboreum), native to the southern U.S., were pyrolyzed at 725 °C with a heating rate of approximately 180 °C/s to mimic the conditions of wildland fires. Tar and light gases were collected and analyzed. Tar from chamise, scrub oak, ceanothus and sparkleberry was abundant in aromatics, especially phenol, while tar from manzanita was mainly composed of cycloalkenes. The four major components of light gases were CO, CO2, CH4 and H2. Estimated values for the high heating values (HHVs) of volatiles ranged between 18.9 and 23.2 (MJ/kg of biomass) with tar contributing to over 80% of the HHVs of the volatiles. Therefore, fire studies should consider the heat released from volatiles present in both tar and light gases during pyrolysis. [ABSTRACT FROM AUTHOR]

In this study, the techno-economic analysis (TEA) and life cycle assessment (LCA) were used to make a comprehensive comparison from the perspectives of economic and environment between the hydrogenation upgrading process and the supercritical ethanol upgrading process based on fast pyrolysis of cornstalk for liquid biofuel. The whole processes of fast pyrolysis and hydrogenation upgrading (FP-HU), fast pyrolysis, and supercritical ethanol upgrading (FP-SU) were simulated by aspen plus software. The mass flow and energy flow of these two processes were calculated according to the simulation results. The TEA results showed that the minimum fuel selling prices (MFSP) of FP-HU and FP-SU were 0.0417 $/MJ and 0.0383 $/MJ. The largest contribution to the MFSPs of FP-HU and FP-SU were the cornstalk cost (0.0084 $/MJ) and the ethanol input cost (0.012 $/MJ), accounting for 18.8% and 31.3% of their MFSP, respectively. The LCA results showed that the abiotic depletion potential (ADP), chemical oxygen demand (COD), and global warming potential (GWP) values of FP-HU were lower compared with FP-SU. The eco-points representing the combined environmental impact of FP-HU and FP-SU were 4.5E − 12 and 5.2E − 12, respectively. Compared to conventional diesel, the ADP, GWP, and respiratory inorganics (RI) of FP-HU and FP-SU decreased by 25.1% and 8.6%, 66.8% and 51.9%, and 95.7% and 96.6%, respectively. The sub-process contribution analysis suggested that the electricity consumption of bio-oil production sub-process and the ethanol consumption of bio-oil upgrading sub-process contributed the most to the eco-points of FP-HU and FP-SU. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Xinjiang University (Natural Science Edition) is the property of Xinjiang University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The development of renewable sources for energy production has assumed a vital role in recent years, particularly with regard to the preservation of energy supplies and the environment. In this regard, municipal green waste (MGW) can be a potential renewable energy source if it is integrated with emerging technology, like pyrolysis. Therefore, this study aimed at investigating the effect of residence time and particle size on the yield and composition of oil derived from MGW using fast pyrolysis in an auger reactor. The residence time and particle size were varied from 1 min to 4 min and 1 mm to 10 mm, respectively, while keeping the temperature constant at 500 °C. At a residence time of 3 min, a 2 mm particle size provided the highest bio-oil yield (39.86%). At this experimental setting, biochar yield of 27.16% and syngas yield of 32.98% were obtained. The characterization of produced bio-oil revealed that a total of nine functional groups were present in the bio-oil. The phenols were highest in amount, followed by aromatics and ketones. The increase in residence time decreased the amount of acidic compounds present in the bio-oil. The water content was decreased by ~11% and the calorific value was increased by ~6% with the increase in particle size from 1 mm to 10 mm. Other properties, such as viscosity, density, cetane number, and flash point, did not change significantly with the change in experimental conditions. With a calorific value of 25+ MJ/kg, although the bio-oil produced from MGW can be used for heating (such as in boilers and furnaces), the use of MGW bio-oil in engines requires appropriate upgrading through procedures like hydrodeoxygenation, catalytic cracking, esterification, etc. [ABSTRACT FROM AUTHOR]

The polymer precursor derived ceramics route is one of the important ways for the preparation of ceramics, and pyrolysis is absolutely necessary in the process. The traditional thermal pyrolysis suffers from slow heating/cooling rate, long processing time, and high energy consumption. In recent years, new technologies, including laser pyrolysis, microwave treatment, and discharge plasma sintering, have attracted the attention in the researchers due to the advantages of fast heating/cooling rate and low energy consumption. This paper summarizes the research progress in rapid pyrolysis in PDCs. The advantages of the new technologies in the preparation of high-performance ceramics are also discussed. [ABSTRACT FROM AUTHOR]

Liquid organic hydrogen carriers (LOHCs), such as methanol and formic acid, offer a reliable solution for the challenges associated with transporting and storing gaseous hydrogen. However, the current industrial LOHCs are costly and in limited supply due to complex synthesis methods involving gasification and Fischer-Tropsch synthesis. An alternative approach utilizing efficient pyrolysis methods can convert biomass into substances that mimic LOHCs, making them a promising avenue for hydrogen storage. Compounds with a high hydrogen content, including glycolaldehyde, acetic acid, and acetol, hold potential as effective LOHCs. This study seeks to assess how the specific properties of biomass impact the resulting products and target molecules, focusing on identifying the primary sources of LOHC compounds. The experimental results indicate that glycolaldehyde primarily originates from cellulose, while acetic acid is mainly derived from hemicellulose. Acetol is produced from both cellulose and hemicellulose. At a pyrolysis temperature of 500 °C and a particle size of 0.38–0.83 mm, corn cob yields a higher quantity of glycolaldehyde, acetic acid, and acetol (107 mg/g) compared to rice husk (85.6 mg/g) and pine (68.9 mg/g) due to its significant cellulose and hemicellulose content. Notably, the primary sources of these hydrogen storage molecules during pyrolysis are the initial biomass pyrolysis products rather than secondary reactions.