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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]

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]

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.)

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]

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.

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.)

ABSTRACT 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.

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.

The conversion of rice straw to bio-oil for substituting asphalt paving materials not only contributes to sustainable development in construction industry, but is also beneficial for resource recovery in agriculture. In this study, rice straw was pyrolyzed to produce bio-oil by using fluidized bed, and the influences of key pyrolysis conditions on product distribution were investigated. Bio-asphalt was prepared by high-speed mixing of pyrolysis bio-oil and petroleum asphalt, and comprehensively evaluated through rheological tests and continuous grading of performance grade (PG). Moreover, microscopic characterization was conducted to further explore the mechanism of bio-oil modification of asphalt. The test results indicate that the yield of bio-oil first rises and then drops with the increase of pyrolysis temperature. As the gas flow rate increases and the biomass particle size decreases, the bio-oil yield shows an increasing trend. The bio-asphalt containing bio-oil from lower pyrolysis temperatures has stronger rutting resistance and lower temperature susceptibility. As the pyrolysis temperature rises, the resistances of bio-asphalt to fatigue and thermal cracking are enhanced. According to continuous PG grading, the widest safe working temperature range is obtained at 450 ℃. Compared to base asphalt, bio-asphalt has superior fatigue and low-temperature performances at high pyrolysis temperatures. Additionally, it can be known from Fourier transform infrared spectroscopy that the modification of petroleum asphalt by bio-oil is a physical fusion process.

Abstract All the countries in the world are now searching for renewable, environmentally friendly alternative fuels due to the shortage and environmental problems related with the usage of conventional fuels. The cultivation of cereal and noncereal crops through agricultural activities produces waste biomasses, which are being evaluated as renewable and viable fossil fuel substitutes. The thermochemical properties and thermal degradation behavior of Sesbania grandiflora residues were investigated for this work. A fluidized bed reactor was used for fast pyrolysis in order to produce pyrolysis oil, char and gas. Investigations were done to analyze the effect of operating parameters such as temperature (350–550 °C), particle size (0.5–2.0 mm), sweeping gas flow rate (1.5–2.25 m3/h). The maximum of pyrolysis oil (44.7 wt%), was obtained at 425 °C for 1.5 mm particle size at the sweep gas flow rate of 2.0 m3/h. Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry methods were used to examine the composition of the pyrolysis oil. The pyrolysis oil is rich with aliphatic, aromatic, phenolic, and some acidic chemicals. The physical characteristics of pyrolysis oil showed higher heating value of 19.76 MJ/kg. The char and gaseous components were also analyzed to find its suitability as a fuel.

Biomass‐derived degraded lignin and cellulose serve as possible alternatives to fossil fuels for energy and chemical resources. Fast pyrolysis of lignocellulosic biomass generates bio‐oil that needs further refinement. However, as pyrolysis causes massive degradation to lignin and cellulose, this process produces very complex mixtures. The same applies to degradation methods other than fast pyrolysis. The ability to identify the degradation products of lignocellulosic biomass is of great importance to be able to optimize methodologies for the conversion of these mixtures to transportation fuels and valuable chemicals. Studies utilizing tandem mass spectrometry have provided invaluable, molecular‐level information regarding the identities of compounds in degraded biomass. This review focuses on the molecular‐level characterization of fast pyrolysis and other degradation products of lignin and cellulose via tandem mass spectrometry based on collision‐activated dissociation (CAD). Many studies discussed here used model compounds to better understand both the ionization chemistry of the degradation products of lignin and cellulose and their ions' CAD reactions in mass spectrometers to develop methods for the structural characterization of the degradation products of lignocellulosic biomass. Further, model compound studies were also carried out to delineate the mechanisms of the fast pyrolysis reactions of lignocellulosic biomass. The above knowledge was used to assign likely structures to many degradation products of lignocellulosic biomass. [ABSTRACT FROM AUTHOR]

This research explores the enhancement of bio-oil quality through upgrading with the magnetic bimetallic oxide (CuO-Fe3O4) catalysts supported on activated rice straw biochar (AcB). These catalysts were employed in a supercritical ethanol-based upgrading process. Various characterization techniques, including elemental analysis, Fourier transform infrared (FTIR), X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), were utilized to characterize the prepared catalysts. This study revealed significant improvements in the physical characteristics and chemical composition of the bio-oil, with an increase in the heating value (HHV) from 21.3 to 32.1 MJ/kg. Esterification and transesterification were identified as key reactions contributing to this improvement. Notably, the pH of bio-oil increased from 4.3 (raw bio-oil) to 5.63 (after upgrading), signifying reduced acidity. The analysis of the bio-oil's chemical composition highlighted a decrease in oxygen content and an increase in carbon and hydrogen content. At the optimum conditions, the application of supercritical ethanol proved to be an efficient method for enhancing the bio-oil's properties. A crucial transformation occurred during the upgrading process and more than 90% of carboxylic acids were converted into esters, primarily ethyl acetate at the optimal conditions. This study has demonstrated the effective enhancement of raw bio-oil from rice straw through the utilization of carbon-based bimetallic oxide catalysts in a supercritical upgrading procedure. [ABSTRACT FROM AUTHOR]

In the current study, bio-oil was produced from sugarcane bagasse via fast pyrolysis process. The process was conducted at 500 °C and 700 °C using a heating rate of 10 °C/s. The values of density, viscosity, acid number, flash point, and heating value of bio-oil produced from pyrolysis of sugarcane bagasse at 700 °C were closer to that of diesel fuel compared to bio-oil produced at 500 °C. The major components of the bio-oil produced from biomass pyrolysis are phenolic compounds. The total phenolic compounds content in the bio-oil prepared via sugarcane bagasse pyrolysis at 500 °C and 700 °C were approximately 48.43 and 58.89%, respectively. These phenolic compounds could decrease the quality of bio-oil. Therefore, in this study, the phenolic compounds contained in the bio-oil produced were extracted by using a mixture of methanol and chloroform for 50 min at temperatures of 25, 40, and 50 °C with stirring speeds of 200, 250, and 300 rpm. Additionally, Folin-Ciocalteu method was employed to determine the phenolic compounds amount in the bio-oil. The chemical composition and physical properties of the bio-oil were also determined. The main chemical components of the bio-oil produced were phenol and furfural. The optimum conditions for phenolic compounds extraction were found at 40 °C and 250 rpm. The highest yields of phenol and distribution coefficients were found to be 58.89% and 1.504 for fast pyrolysis at 500 °C and 48.43% and 1.528 at 700 °C. [ABSTRACT FROM AUTHOR]

The great potential of bio-products generated from agro-industrial residues from the biomass processing, as is the case with the green coconut fibers (Cocos nucifera L. var. dwarf), makes Brazil stand out in the field of transformation of these residues, mainly due to its high biodiversity and favorable climatic conditions. In this work, residual green coconut fibers were used in the production of bio-oil by pyrolysis. The bio-oil was fractionated using preparative liquid chromatography (PLC) in silica using solvents of different polarities: hexane, hexane/toluene, toluene/dichloromethane, dichloromethane/acetone, and methanol. Bio-oil and its fractions were analyzed by gas chromatograph /quadrupole mass spectrometer (GC/qMS). The concentration of each compound was carried out by multiplying the percentage area of the corresponding peak by the mass yield of the respective fraction. PLCof bio-oil increased the number of compounds identified by about 170% compared to the original bio-oil (non-fractionated), besides allowing the isolation of nonpolar compounds (mostly hydrocarbons) from polar compounds (mainly phenols, aldehydes, and ketones). Anotheradvantage of PLC was the increase in the number of hydrocarbons identified in the fractions, as opposed to the crude bio-oil analysis. Among the major compounds, phenols can be highlighted, besides furfural derivatives and hydrocarbons, which indicates the potential use of bio-oil mainly for industrial purposes.

The current paper presents research on bio-oil production from Tung seed residues fed at 500 g/h via fast pyrolysis in a fluidized-bed. The objective was to investigate the influence of temperature on bio-oil production in a pyrolysis process. Three portions Tung residues were studied, Tung seed outer shells (TO), Tung seed inner shells (TI), and pressed residues of oil seeds (RS), all having particle sizes of 0.150–0.500 mm. The process temperatures were 350–500 °C. The physical and chemical properties of pressed residue particles were characterized by ASTM standard methods. Bio-oil component identification was done using GC-MS. Experimentally derived data showed an optimal pyrolysis temperatures for all three types of Tung residues (TO, TI and RS) of 400 °C, yielding respective maximum bio-oil yields of 53.46, 52.81, and 62.85 wt% on a dry basis (db). Apart from having highest bio-oil yield, RS produced bio-oil with the highest carbon content, leading to its greatest lower heating value (LHV), 28.05 MJ/kg (db). The main bio-oil components were acids, nitrogen compounds, and hydrocarbons. Char yield was reduced with increased temperature. Tung seed outer shells produced the highest char level (39.26 wt%) while RS gave highest char quality in term of density and heating value.

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.

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.

The realization of a circular economy calls for maximum utilization of existing resources with no recoverable waste after the process cycle. During fast pyrolysis of biomass to produce bio-oil for energy purposes, solid residues in form of bio-char are generated. In this study, residual char after pyrolytic-oil extraction from rice husks was activated using steam at 800 °C to produce activated carbon (AC). The formed AC was characterized and evaluated for removal of heavy metals from contaminated water. Box Behnken Design of Response Surface Methodology was used to optimize the removal of Cu2+, Co2+, Zn2+, Pb2+, and Ni2+ from water. The process conditions were: adsorbent dose (2–12 g/L), contact time (30–180 min) and temperature (25–70 °C). Characterization of AC revealed surface area and pore volume of 407 m2g-1 and 0.22 m3g-1, respectively. For all developed models, adsorbent dose, and contact time were the most significant terms. A linear model best fits Cu2+ remediation, while quadratic models best-fit removals of Co2+, Zn2+, Pb2+, and Ni 2+. Heavy metal removal efficiency increased with increasing adsorbent dose, contact time and temperature. Optimum treatment parameters were: adsorbent dose (11.90 g/L), contact time (172.5 min), temperature (54 °C) with removal efficiencies of 98.2%, 84.1%, 75.3%, 98.1%, 75.7% for Cu2+, Co2+, Zn2+, Pb2+, and Ni2+, respectively. Adsorption data best fitted Langmuir isotherm and pseudo second order models. These results confirm the applicability of AC from pyrolytic-oil residual char for adsorption of heavy metals. Use of AC from residual char in water treatment contributes to circular economy.

A novel self-mixing down tube (SDT) pyrolyzer has been developed, which can separate the heat carrying particles preheated in the fluidized bed from the coal, and the two can be mixed through a specific structure to instantly heat the coal particles to a predetermined temperature. The present study investigated the pyrolysis behavior of low-rank coal with hot silica sand heat-carrying particles adopting TG-FTIR. Identifies optimal conditions for maximum tar production in a laboratory-scale SDT using a significantly larger range of coal feed rates (4 kg/h). An increase in the degree of coal metamorphism increased the initial temperature and the yield of char. The tar yield from Huolinhe lignite coal (6.56 %) and Daliuta bituminous coal (7.48 %) showing a trend of first increased and then decreased with elevating the operating temperature and optimal temperature at 520 °C, respectively. The effect of coal particle size on tar yield mainly comes from the different degrees of secondary cracking caused by contact with solid heat-carrying particles as well as the differences in the content of macerals. GC‒MS spectra of tar and deposited carbon on silica sand indicated that heavy tar can easily deposit on the surface of sand and form char through polymerization reactions.

The need for polyethylene terephthalate recycling is associated with the formation of significant amount of its waste, which should be reprocessed due to the growth of polymer production and consumption of plastic products used in light, chemical, medical industries, in mechanical engineering and instrument making. The main share of polyethylene terephthalate (PET) recycling processes is chemical methods through which various monomers are generated. After purification and modification of these monomers, valuable petrochemical raw materials can be yielded. The review describes the principles and mechanisms of polyethylene terephthalate degradation upon pyrolysis. The influence of the heating rate during pyrolysis (fast, slow), type of raw material (pure polymer, polymer waste), additives (modifiers, stabilizers, fire retardants), type of reactor in the process (horizontal, vertical, fixed bed reactor, fluidized bed reactor, conical tip reactor, rotating dc arc plasma reactor) is considered, as well as the effect of processing conditions such as temperature, amount of raw material, pressure, atmosphere, and presence of catalyst on the quantitative and qualitative composition of oxygen-containing compounds formed in the gas fraction, pyrolysis oil, and semi-coke. The influence of additives of various polymers in a mixture with polyethylene terephthalate on the formation of products (gas fraction, pyrolysis oil, and semi-coke), additives of plant biomass, and food waste is demonstrated. The effect of microwave radiation on the polyethylene terephthalate pyrolysis is considered. [ABSTRACT FROM AUTHOR]

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Co-pyrolysis is one possible method to handle different biomass leftovers. The success of the implementation depends on several factors, of which the quality of the produced bio-oil is of the highest importance, together with the throughput and constraints of the feedstock. In this study, the fast co-pyrolysis of palm kernel shell (PKS) and woody biomass was conducted in a micro-pyrolyser connected to a Gas Chromatograph–Mass Spectrometer/Flame Ionisation Detector (GC–MS/FID) at 600 °C and 5 s. Different blend ratios were studied to reveal interactions on the primary products formed from the co-pyrolysis, specifically PKS and two woody biomasses. A comparison of the experimental and predicted yields showed that the co-pyrolysis of the binary blends in equal proportions, PKS with mahogany (MAH) or iroko (IRO) sawdust, resulted in a decrease in the relative yield of the phenols by 19%, while HAA was promoted by 43% for the PKS:IRO-1:1 pyrolysis blend, and the saccharides were strongly inhibited for the PKS:MAH-1:1 pyrolysis blend. However, no difference was observed in the yields for the different groups of compounds when the two woody biomasses (MAH:IRO-1:1) were co-pyrolysed. In contrast to the binary blend, the pyrolysis of the ternary blends showed that the yield of the saccharides was promoted to a large extent, while the acids were inhibited for the PKS:MAH:IRO-1:1:1 pyrolysis blend. However, the relative yield of the saccharides was inhibited to a large extent for the PKS:MAH:IRO-1:2:2 pyrolysis blend, while no major difference was observed in the yields across the different groups of compounds when PKS and the woody biomass were blended in equal amounts and pyrolysed (PKS:MAH:IRO-2:1:1). This study showed evidence of a synergistic interaction when co-pyrolysing different biomasses. It also shows that it is possible to enhance the production of a valuable group of compounds with the right biomass composition and blend ratio. [ABSTRACT FROM AUTHOR]

The total production of global plastics is up to 400 million tons per year. Nearly 80% of the used plastics are directly landfilled or dumped in the environment, leading to the generation and release of microplastics, which poses a great threat to both environment and human health. How to recycle plastic waste efficiently and environmentally has become a common concern worldwide. Among the plastic waste recycling methods, chemical recycling such as pyrolysis can realize the transformation from polymer to high-value products. This paper summarizes the research and industrialization progress of four different plastic waste pyrolysis technologies, namely fast pyrolysis, catalytic pyrolysis, oxidative pyrolysis and hydro-pyrolysis. The challenges faced by the pyrolysis of plastic waste is discussed and the future development direction of various pyrolysis technologies is also outlooked. It is expected that some more efficient, environmentally friendly, and economical technologies of plastic waste pyrolysis can be explored in the future, to meet the growing demand for environmental protection and sustainable development.

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.

Developing low-cost and high-activity catalysts is one of the keys to promoting the catalytic pyrolysis of waste plastics to fuels for plastic recycling. This work studied the effect of clay as the catalyst on mixed plastic pyrolysis for fuel and energy recovery. Four kinds of clay, including nanoclay, montmorillonite, kaolin, and hydrotalcite, were used as catalysts for the pyrolysis of mixed plastic consisted of polyethylene terephthalate, polystyrene, polypropylene, low-density polyethylene, and high-density polyethylene. The product yield and distribution varied with different clay in pyrolysis. The highest yield of oil was 71.0 % when using montmorillonite as the catalyst. While the highest contents of gasoline range hydrocarbons and diesel range hydrocarbons in the oil were achieved when using kaolin and nanoclay, respectively as catalysts. For the gas products, the CO, C2H4, C2H6, C3H6, and C4H10 increased with decreased CO2 in the gaseous products when using clay as catalysts. In general, the mild acidity of clay catalyst was essential to improve the oil yields and the proportion of the gasoline or diesel range fuels in the catalytic pyrolysis of mixed plastic waste.

Commercial fast pyrolysis technologies use bed materials, normally natural sand mainly consisting of quartz, acting as circulating heat carrier materials. Nowadays, the commercial conversion of biomass into fast pyrolysis bio-oil (FPBO) is still using ash-lean woody residues as a feedstock since the application of more abundant and possibly cheaper ash-rich agricultural biomass is currently at a significantly lower technology readiness level (TRL). To promote FPBO production from ash-rich biomass, the ash-related issues during the operation process need to be further studied. In the present investigation, the characteristics and formation process of layers formed on quartz bed particles, collected from a bench-scale fast pyrolysis unit based on the rotating cone technology, were studied. Two grass residues, representative of typical Si-K-rich agricultural biomass fuels, were used as feedstocks. Quartz bed particles at different sampling times from startup with fresh bed particles were collected. Scanning Electron Microscopy/Energy-Dispersive Spectroscopy (SEM/EDS) was employed to characterize the layer properties. Bed particle layers exhibited an uneven and discontinuous distribution on the quartz surface. This distribution over bed particles, as well as layer thickness, increased with the operational time. The dominating elements contained in layers were Si, K, Ca, and Cl (excluding O), which resembled that of individual bed ash particles found in the bed samples. In addition, the interpretation of the results was supported by thermodynamic equilibrium calculations. The findings suggest that the process of layer formation was governed by the direct adhesion of non-melted bed ash particles during the fast pyrolysis of grass.

The fast depletion of fossil fuels and growing concerns about environmental sustainability have increased interest in using biomass as a renewable energy source. Fast pyrolysis, a thermochemical conversion process, has emerged as a promising technique for converting biomass into valuable biofuels and bio-based chemicals. The aim of this literature review is to comprehensively analyze recent advances in biomass fast pyrolysis, focusing on the principles, process parameters, product yields, and potential applications of biomass fast pyrolysis. This comprehensive review, based on an in-depth analysis of 61 scientific papers and 4 patents, provides an overview of various biomass technologies (combustion, gasification, pyrolysis) used for biofuel production. It focuses on the principles, benefits and applications of these technologies and serves as a valuable resource for researchers, engineers and policy makers. Based on the wealth of information from rigorously selected sources, we explore the key process parameters and reactor types associated with each technology, providing insight into its efficiency and product composition. [ABSTRACT FROM AUTHOR]

Liquid products obtained by the fast pyrolysis process applied to biomass can be used as chemical raw materials and liquid fuels. In this study, tea bush, walnut shell, and pine cone samples selected as biomass samples were obtained from Trabzon and Rize provinces in the Eastern Black Sea Region and used. When considered in terms of our region, the available biomass waste samples are easy to access and have a high potential in quantity. To employ them in the experimental investigation, these biomass samples were first ground, sieved to a particle size of 1.0 mm, and mixed. A fast pyrolysis process was applied to this obtained biomass mixture in a fixed-bed pyrolysis reactor. The effects of temperature, heating rate, and nitrogen flow rate on the product yields of the fast pyrolysis technique used on the biomass mixture are examined. A constant particle size of 1.0 mm, temperatures of 300, 400, 500, 600, and 750 °C, heating rates of 100, 250, 400, and 600 °C.min−1, and flow rates of 50, 100, 200, and 300 cm3.min−1 were used in tests on fast pyrolysis. The studies showed the 500 °C pyrolysis temperature, 100 °C min−1 heating rate, and 50 cm3.min−1 nitrogen flow rate gave the maximum liquid product yield. The liquid product generated under the most compelling circumstances is analyzed to determine moisture, calorific value, fixed carbon, ash, raw coke, and volatile matter. Additionally, the crude bio-oil heating value, measured at 5900 cal/g and produced under the most favorable pyrolysis circumstances, rose by around 40% compared to its starting material. The liquid product obtained from rapid pyrolysis experiments can be used as liquid fuel. The evaluation of the potential of chemical raw materials can be a subject of research in a different discipline since there are many chemical raw materials (glycerine, furfurals, cellulose and derivatives, carbonaceous materials, and so forth) in fast pyrolysis liquids. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel approach (HTC combined with fast pyrolysis) implemented to valorise AS. • Maximum deoxygenation and demineralisation rates were obtained with HTC. • Optimal HTC operational parameters were selected according to pyrolytic bio-oil. • Fast pyrolysis of hydrochars helped enrich bio-oil mainly in produced bio-phenolics. In this study, it was found that hydrothermal carbonization (HTC) can be an effective method for almond shell (AS) valorization. The severity of HTC treatment had a significant effect on hydrochar yields, with higher severity promoting carbonization but reducing yields. Furthermore, the work found that HTC treatment effectively demineralized biomass samples by removing inorganic material that could catalyze carbonization. As residence time or temperature increased, the amount of carbon increased, while the amount of oxygen decreased. An acceleration in thermal degradation was detected for hydrochars after pretreating for 4 h. The hydrochars showed they had a higher volatile content than untreated biomass, making them potentially useful for producing quality bio-oil through fast pyrolysis. Finally, HTC treatment led to the production of valuable chemicals such as guaiacol and syringol. For syringol production, HTC residence time had more effect than HTC temperature. However, high HTC temperatures benefited levoglucosan production. Overall, the results demonstrated the potential for HTC treatment to be an effective method for valorizing agricultural waste, offering the possibility of producing valuable chemicals. [ABSTRACT FROM AUTHOR]

Greenhouse vegetables produce high amounts of wastes which need to be addressed for efficient life cycle of raw materials and may cause environmental pollution if managed improperly. In this study, the effects of three parameters (pyrolysis temperature, catalyst type, and catalyst amount) on the distribution of products and quality of bio-oil obtained from fast pyrolysis of the mixture of greenhouse vegetables wastes (GVW) such as tomato, pepper, and eggplant were investigated. Fast pyrolysis experiments were carried out in a drop-tube-reactor system by using four different catalysts such as cerium oxide (CeO2), zinc oxide (ZnO), zirconium oxide (ZrO2), and Lewis acid (50% FeCl3 + 50% Na2SO4) with the amounts of catalysts as 4, 7, and 10 g and pyrolysis temperatures of 450, 500, and 550 °C. Bio-oil samples were characterized by elemental and GC-MS analyses. The use of different catalysts affected the products distribution and bio-oil chemical composition. Biochar yield increased with a relatively low pyrolysis reaction temperature, whereas the gas yield increased with temperature and catalyst amount. The bio-oil yield varied with catalyst type, but pyrolysis temperature and amount of catalyst had no significant effect. The bio-oil yield increased during catalytic fast pyrolysis (CFP) and the average maximum bio-oil yield of 45.4% was obtained during Lewis acid application. The lowest and highest bio-oil yields of 36.67% and 46.93% were obtained during the applications of 7g ZnO and 10 g Lewis acid at 450 °C, respectively. Chemical groups such as acids, furans, ketones, phenols, hydrocarbons, and benzene were abundant in the bio-oil samples obtained from CFP of GVW. Therefore, GVW is a promising feedstock to produce biofuels and useful chemicals through fast pyrolysis. [ABSTRACT FROM AUTHOR]

This paper elucidates catalytic and non-catalytic pyrolysis characteristics of sludge obtained from the biological treatment of textile and leather industrial wastewater. Iso-conversional model-free methods, such as Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS) and Friedman, were employed to evaluate the kinetic and thermodynamic parameters. The E a (activation energy) values of non-catalytic and catalytic pyrolysis with y-zeolite and activated alumina (Al2O3) were determined via KAS method to be in the range of 84.66–291.18, 73.12–197.17 and 84.66–217.44 kJ/mol, respectively, whereas similar trends were observed when the other two methods were used. Gas chromatography/mass spectrometer (GC/MS) analyses showed that the oil obtained from the non-catalytic procedure was rich in fatty acids, steroidal compounds and N-compounds. Activated alumina was effective in removing nitrogen-containing compounds from the oil while y-zeolite promoted deoxygenation and deacidification reactions and, as a result, the oil became rich in alkanes and alkenes which improved its quality as a fuel. [ABSTRACT FROM AUTHOR]

Extensive research has demonstrated the advantageous utilization of medium–low temperature fast pyrolysis (FP) for biomass, yielding high–grade liquid–phase chemicals or fuels. However, the field of FP–based high–performance solid biochar research still presents several gaps. Herein, a one–step versus two–step method for biomass H3PO4 activation under FP was comparatively analyzed for the first time, and efficiently activated carbons (ACs) for dye removal were successfully synthesized at a low temperature (723 K). Investigation of methylene blue (MB) adsorption revealed that the one–step sample P–H–0.5, possessing a specific surface area of 1004 m2·g−1, exhibited a remarkable adsorption capacity of 695.54 mg·g−1 with an ultra–high removal rate (99.94%, C0 = 150 mg·L−1). The two–step sample P–2–H–2, a modified byproduct of FP, achieved efficient dye adsorption in the shortest time (2 min, 383.91 mg·g−1). This originated from the well–developed surface macropores and elevated group content derived from phosphorus (P)—modification. Both adsorption data were well–fitted with pseudo–second–order kinetics and the Langmuir model, revealing the presence of chemical effects and the dominance of monolayer adsorption. A more detailed kinetic study suggested intrapore transport primarily governed the adsorption process on P–H–0.5, whereas P–2–H–2 relied on surface diffusion. FTIR and XPS revealed notable differences in the active sites between the two methods. Aside from –OH, –COOH with C–O–P, the P elements of P–H–0.5 were classified as C–P–O3 and C2–O–P2, demonstrating the ability of one–step FP to introduce heteroatoms into carbon defects. The basic interactions of ACs with MB were π–π stacking and hydrogen bonding established by –OH–containing groups. At a suitable pH (>5), most H+ was removed from the surface, and the electrostatic attraction became the strongest linking force. Both ACs exhibited exceptional reusability, with removal rates surpassing 90% of the initial rate after four cycles of regeneration. [ABSTRACT FROM AUTHOR]

Different parameters are effective on bio-oil yield and quality during the production of bio-oil from biomass through fast pyrolysis. Knowing the optimum values of these parameters is important to obtain bio-oil in the desired yield and quality and therefore economic production of energy. This study investigated the optimum process conditions of fast pyrolysis in a drop-tube-reactor system for high yield and quality bio-oil production from the mixture of greenhouse vegetable wastes (GVW) such as tomato, pepper, and eggplant. The experimental design was performed for optimization by using response surface methodology (RSM) with central composite design (CCD). The effects of biomass particle size (0.5–1.5 mm), pyrolysis temperature (450–600 °C), and nitrogen gas flow rate (1000–1700 mL min−1), and their reciprocal interaction were determined. The optimum conditions were determined as a particle size of 1.5 mm, a reaction temperature of 400 °C, and a nitrogen gas flow rate of 300 mL min−1. The maximum bio-oil yield was obtained as 49 wt% at the optimum fast pyrolysis conditions. GC–MS analysis of bio-oil sample obtained under optimum process parameters indicated an abundance of hydrocarbon and acid contents. [ABSTRACT FROM AUTHOR]

Bitumen is a dark brown to black colour glue material majorly used in the construction of bound layers of pavements. It is treated as a hazardous material because of its higher PAH (polycyclic aromatic hydrocarbons) content and presence of hydrogen sulphide. These characteristics of conventional bitumen affect humans as well as the environment, and conventional bitumen is a non-renewable resource that is getting depleted at a very rapid rate. This demands the need for an alternative binder that can mitigate ill effects created by conventional bitumen and address the future requirements of bitumen such as sustainability and circular economy for pavement construction. This review analysis focuses on biomass characterization in terms of an industrial, elemental, structural component and fraction content analysis. Along with these biomass sources and their upgrade techniques, conversion methods or preparation processes used to produce bio-oil and bio-bitumen from different biomass forms, practical application and life cycle inventory were reviewed, and their performance on physical, mechanical, rheological and chemical properties was studied. In addition to this, the effect of biochar as bitumen additive or filler on the performance characteristics of bitumen was studied. It is concluded that with the type and dosage of bio-oil used, the bio-binder production varies, and this bio-binder is only effective at moderate and low temperatures. Bio-oils do not evaporate or degrade with time; instead, they become a permanent part of the binder, preventing phase separation. Optimal usage of biochar improves the properties like viscosity, failure temperature, ageing resistance and deformation. [ABSTRACT FROM AUTHOR]

To generate updated and transparent capital cost estimates for biomass fast pyrolysis equipment, refinery fluidized catalytic cracking design and sizing principles are examined and extended to pyrolysis of woody biomass. Capital costs for the sized equipment are estimated with process‐industry software. A one‐dimensional flow simulation with pyrolysis kinetics is leveraged to validate the fluidization conditions and thermal energy balance. After successful sizing and a system cost estimate of $2.8 M (in 2016 US$) at the biorefinery scale of 1000 metric tons per day (MTD), these methods were exercised for even smaller equipment at the distributed pyrolysis scale with modifications to the process design constraints, and not directly comparable with the 1000 MTD case, arriving at capital cost estimates of $1.2 M for a 500 ton/day system and $0.9 M for a 200 ton/day system. It is noted that this work only estimates purchased equipment costs at the ±50% accuracy level; there are significant other custom factors applicable to each installation based on location, maturity, scale, complexities during installation, engineering and licensing costs, etc. that need to be added on to these estimates to derive investment costs. [ABSTRACT FROM AUTHOR]

This study employs a wire-mesh reactor (WMR) to understand the primary release and transformation of inorganic and organic sodium during fast pyrolysis of various sodium-loaded lignin samples at 300–800 °C. Due to the minimization of volatile-char interactions in WMR, the overall sodium release during lignin pyrolysis is relatively low, i.e., ∼9–11% and ∼7–14% for the inorganic and inorganic sodium loaded lignin, respectively. The presence of the inorganic sodium in the condensed volatiles (so-called oil) clearly indicates the important role of thermal ejection in the release of the inorganic sodium, since sodium salts are unlikely to evaporate under current conditions. While the release of the organic sodium into oil can be due to both thermal ejection of aerosols and evaporation of low carboxylates. Despite the low sodium release, significant transformation of the inorganic and organic sodium can take place during lignin pyrolysis. For the inorganic sodium loaded lignin, the inorganic sodium decreases continuously from ∼67% at 300 °C to ∼42% at 800 °C, accompanied by a steady increase in the organic sodium (i.e., the ion-exchangeable sodium) from ∼17% at 300 °C to ∼37% at 800 °C. While for the organic sodium loaded lignin, its transformation into the inorganic sodium is faster at higher temperatures, leading to a large increase in the inorganic sodium (i.e., carbonates) from ∼9% at 300 °C to ∼48% at 800 °C, as well as a reduction in the organic sodium from ∼79% at 300 °C to ∼28% at 800 °C. The data generated in this study will be important to understand the catalytic mechanism of sodium during thermochemical processing of alkali lignin for the production of bioenergy and biofuels. [ABSTRACT FROM AUTHOR]