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The production of aviation biofuel precursors from biomass-derived ketones by heterogeneous catalysis has been hindered by the low catalytic activity. Herein, a series of Cu-doped metal oxide catalysts were prepared for the conversion of biomass-derived ketones to aviation biofuel precursors. Solvent-free cyclopentanone conversion via aldol condensation reached 91.1 % over Cu/Al 2 O 3 with 100 % selectivity toward dimer and trimer oxygenated species, all of which are aviation biofuel precursors. This catalyst primarily contains Cu 2 O and Cu nanoparticles which are uniformly dispersed across the Al 2 O 3 surface. From in situ DRIFTS and DFT results, the incorporation of Cu species onto Al 2 O 3 not only increased the diversity of Lewis acidic sites, but also changed the adsorption of C = O groups, which lead to the increased aldol condensation activity of Cu/Al 2 O 3 . This study provides insight on the design of heterogeneous catalysts suitable for the solvent-free synthesis of aviation biofuel precursors from biomass-derived ketones., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Ltd.)

The production of aromatic hydrocarbons from cellulose by zeolite-catalyzed fast pyrolysis involves a complex reaction network sensitive to the zeolite structure, crystallinity, elemental composition, porosity, and acidity. The interplay of these parameters under the reaction conditions represents a major roadblock that has hampered significant improvement in catalyst design for over a decade. Here, we studied commercial and laboratory-synthesized ZSM-5 zeolites and combined data from 10 complementary characterization techniques in an attempt to identify parameters common to high-performance catalysts. Crystallinity and framework aluminum site accessibility were found to be critical to achieve high aromatic yields. These findings enabled us to synthesize a ZSM-5 catalyst with enhanced activity, which offers the highest aromatic hydrocarbon yield reported to date., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Bio-oils derived from the pyrolysis of lignin-based biomass often contain a variety of oxygenated compounds, which can compromise their usefulness as a fuel. To improve the quality of bio-oil, catalytic hydrodeoxygenation (HDO) is a crucial step that removes oxygen from the oil in the form of water. In this study, we showed that MFI nanosheets are excellent supports for Ru-catalysts. We synthesized highly crystalline MFI nanosheets using a simple hydrothermal seeding procedure; the final material was obtained in 56 h of crystallization. We investigated the activity of Ru supported on different materials. Our findings indicated that Ru supported on hierarchical MFI demonstrated excellent activity in HDO of guaiacol. Our results demonstrated that Ru/ZNS-56 achieved nearly 100% selectivity towards cyclohexane under mild conditions (200 °C, 50 bar H2, 1 h). [ABSTRACT FROM AUTHOR]

Biomass/coal co-combustion presents a promising avenue for reducing carbon dioxide emissions. However, the mechanism of NO generation during co-combustion in pulverized coal-fired furnaces remains unclear. Herein, this study investigates NO emission characteristics at elevated temperatures, emphasizing mechanistic understanding. The experiments and simulations were conducted across temperatures ranging from 1000 °C to 1600 °C. In addition to exploring how fundamental conditions (temperature, oxygen concentration, and biomass blending ratio (BBR)) affect NO generation, the study also investigates the interactions between biomass and coal, as well as between fuel NO and thermal NO. The results indicate that the change in NO production with increasing temperature is non-monotonic, attributable to the combined contribution of fuel NO and thermal NO. Moreover, the interaction between biomass and coal manifests predominantly during the char combustion stage, owing to the disparate combustion characteristics and reactivity of biomass char and coal char. Numerical simulations were highly consistent with the experimental findings, underscoring a reduction in the rate of production (ROP) for major elementary reactions leading to NO formation as the BBR increased, consequently mitigating NO emissions. By integrating experimental insights with reaction kinetics calculations, this study proposes pathways for fuel NO and thermal NO generation during co-combustion at high temperatures, involving precursors such as NCO, HNO, and NH. These findings offer a deeper understanding of the mechanism of fuel NO and thermal NO emission during co-combustion at high temperatures. [Display omitted] • NO emission characteristics at 1000–1600 °C of co-combustion were investigated. • Biomass-coal interaction on NO emission was explored using PCA and deviation analysis. • Non-monotonic change in NO emission with temperature, due to thermal NO formation. • Temperature increase affected the conversion pathways of NH and HNO. • Proposed thermal NO and fuel NO generation paths at high temperatures. [ABSTRACT FROM AUTHOR]

• N-doped biochar catalyst showed a higher degree in auto-reduction of Ru • Revealed the promoting effect of N-containing species on CO 2 methanation • CO 2 conversion of 93.8% with CH 4 selectivity of 99.7% was achieved on Ru/N-ABC-600 N-doped biochar with a high nitrogen content and tuned pore structure was obtained from Pinus sylvestris by an in-situ pyrolysis process with simultaneous doping nitrogen and activation where urea was used as a nitrogen precursor and NaHCO 3 was employed as the activator. To test the feasibility of N-doped biochars obtained under different pyrolysis temperatures as catalyst supports, a series of Ru catalysts were prepared for use in the methanation and the catalysts were labelled as Ru/N-ABC-x, where x represented the pretreatment temperatures(500, 600 and 700 °C). Besides, the catalytic test of Ru/ABC which was prepared under the same conditions without N modification was also conducted for comparison. The probe reaction test of CO 2 methanation showed that the Ru/N-ABC-600 catalyst with the highest pyridinic-N (37.7%) content had superior or comparable catalytic performance to Ru/N-ABC-500 and Ru/N-ABC-700 prepared from N-doped biochar with different pyridinic-N content. A high CO 2 conversion of 93.8% with a CH 4 selectivity of 99.7% was achieved on Ru/N-ABC-600 under the optimum reaction conditions (380 °C, 1 MPa, n(H 2)/n(CO 2) of 4, with a gas hourly space velocity of 6000 mL·g-1·h-1). This work provides an effective strategy for the utilization of biochar to develop highly active catalysts for CO 2 methanation. [ABSTRACT FROM AUTHOR]

Reactive catalytic fast pyrolysis (RCFP) of biomass with atmospheric pressure hydrogen was investigated in a lab-scale fluidized bed reactor with varying reaction conditions (temperature and hydrogen concentration) and catalysts. Presence of atmospheric hydrogen with candidate RCFP catalysts was found to improve the yield and quality of bio-crude and minimize the char and coke formation. A molybdenum-based catalyst was the most effective at hydrodeoxygenating biomass pyrolysis vapors to produce a hydrocarbon-rich bio-crude intermediate with low oxygen content (＜10 wt%). Higher hydrogen concentration and moderate reaction temperature (450 °C) favored higher bio-crude yields and quality. A yield of 43.2 C% in the C4+ organic fraction with as low as 6.2 wt% oxygen in the liquid was obtained under optimized reaction conditions. The resulting bio-crude contained primarily aliphatic and aromatic hydrocarbons, with small amounts of simple ketones, furans, and phenols. Up to 41.5% carbon in the biomass feed was converted into gas and condensable hydrocarbons with 29.7% in the condensable C4+ fraction. The improved bio-crude quality is expected to be more compatible with existing petroleum refining infrastructure. [ABSTRACT FROM AUTHOR]

At RTI, we are developing a catalytic fast pyrolysis process with a new solid acid catalyst, the performance of which has been evaluated in a pilot-scale reactor using loblolly pine. More robust technology development requires a deeper understanding of the influence of the feedstock properties of process performance defined by the organic liquid yield and composition. Seven types of woody and herbaceous biomass were tested in a 2.54 cm diameter fluidized-bed reactor. This study shows that the product distribution and biocrude composition vary widely with different feedstocks. The yield of organic biocrude is in the range of 14.0-20.8 wt % for the tested feedstocks. The yields of incondensable gases and carbonaceous solids vary significantly from feedstock to feedstock, which may be because of the variation of the ash content in the feedstock. A feedstock with a higher ash content generates more gases; specifically more CO2 but not necessarily more CO. The chemical composition, which includes lignin, hemicellulose, and cellulose, also affects the biocrude composition and the yield of gases. We also demonstrated a positive correlation between the cellulose content and CO yield and a negative correlation between the hemicellulose content and CO yield. [ABSTRACT FROM AUTHOR]

The effect of alkali and alkali earth metals (AAEMs) on yields of hydrocarbons from catalytic pyrolysis of biomass was investigated. Experiments were performed in a tandem micro-reactor that segregates the biomass from the zeolite catalyst ( ex-situ catalytic pyrolysis). It was found that even trace amounts of AAEMs added to cellulose as acetate salts dramatically reduced the yields of hydrocarbons. Both the concentration and types of AAEM salts impacted product distribution. The yield of aromatics and olefins decreased monotonically with increasing concentration of AAEMs. The effect of AAEMs on reducing hydrocarbon yields followed the order: K + > Na + > Ca 2+ > Mg 2+ . Two pretreatments of biomass were investigated to alleviate the catalytic effects of AAEMs that naturally occurs in biomass: acid-washing and acid-infusion. It was found that pretreated biomass increased yields of hydrocarbons apparently by suppressing reactions that would otherwise convert carbohydrate to non-condensable gases and char. [ABSTRACT FROM AUTHOR]

Pyrolysis of Manchurian ash (Fraxinus mandshurica Rupr.) sawdust with four zeolite molecular sieve catalysts was performed on a thermogravimetric analyzer coupled with a Fourier transform infrared spectrometer. Pyrolysis of pure Manchurian ash and three main components, viz. cellulose, xylan, lignin, was also carried out as reference. The four zeolite catalysts investigated in this study (viz. HZSM-5, H-β, USY and Na-Y) all catalyze the dehydration reaction, restrain the release of volatiles, and obviously promote the final residue yields. Y-type catalysts show the most evident catalytic effect, such as restraining the formation of aldehydes, acids, and ethers, and promoting that of isoalkanes and aromatics. The preferred catalyst should have both high activity for deoxygenating and selectivity for hydrocarbon production. [ABSTRACT FROM AUTHOR]

Abstract: Despite the increasing importance of biomass pyrolysis, little is known about the pyrolysis behavior of lignin—one of the main components of biomass—due to its structural complexity and the difficulty in its isolation. In the present study, we extracted lignins from Manchurian ash (Fraxinus mandschurica) and Mongolian Scots pine (Pinus sylvestris var. mongolica) using the Bjorkman procedure, which has little effect on the structure of lignin. Fourier transform infrared (FTIR) spectrometry was used to characterize the microstructure of the Bjorkman lignins, i.e., milled wood lignins (MWLs), from the different tree species. The pyrolysis characteristics of MWLs were investigated using a thermogravimetric analyzer, and the release of the main volatile and gaseous products of pyrolysis were detected by FTIR spectroscopy. During the pyrolysis process, MWLs underwent thermo-degradation over a wide temperature range. Manchurian ash MWL showed a much higher thermal degradation rate than Mongolian Scots pine MWL in the temperature range from 290–430 °C. High residue yields were achieved at 37 wt.% for Mongolian Scots pine MWL and 26 wt.% for Manchurian ash MWL. In order to further investigate the mechanisms of lignin pyrolysis, we also analyzed the FTIR profiles for the main pyrolysis products (CO2, CO, methane, methanol, phenols and formaldehyde) and investigated the variation in pyrolysis products between the different MWLs. [Copyright &y& Elsevier]

Catalytic hydropyrolysis via the introduction of external hydrogen into catalytic pyrolysis process using hydrodeoxygenation catalysts is one of the major approaches of bio-oil upgrading. In this study, hydrodeoxygenation of acetone over Mo/HZSM-5 and HZSM-5 were investigated with focus on the influence of hydrogen pressure and catalyst deactivation. It is found that doped MoO3 could prolong the catalyst activity due to the suppression of coke formation. The influence of hydrogen pressure on catalytic HDO of acetone was further studied. Hydrogen pressure of 30 bar effectively prolonged catalyst activity while decreased the coke deposition over catalyst. The coke formation over the HZSM-5 and Mo/HZSM-5 under 30 bar hydrogen pressure decreased 66% and 83%, respectively, compared to that under atmospheric hydrogen pressure. Compared to the test with the HZSM-5, 35% higher yield of aliphatics and 60% lower coke were obtained from the Mo/HZSM-5 under 30 bar hydrogen pressure. Characterization of the spent Mo/HZSM-5 catalyst revealed the deactivation was mainly due to the carbon deposition blocking the micropores and Bronsted acid sites. Mo/HZSM-5 was proved to be potentially enhanced production of hydrocarbons. [ABSTRACT FROM AUTHOR]

• The OTP of biomass pseudo component (cellulose, hemicellulose, and lignin) was carried out. • The oxidative torrefaction mechanism was investigated at varying OTP temperatures and oxygen concentrations. • The element distribution in biomass pseudo component was optimized after OTP. • The chemical compounds in torrefied liquid products from biomass pseudo component were highly differentiated. • The concentrations of torrefied gaseous products of biomass pseudo component were ranked as CO 2 > CO > H 2 ≈ CH 4. The oxidative torrefaction pretreatment (OTP) is a promising approach to upgrade the quality of biomass. This work investigated the oxidative torrefaction mechanism based on the OTP experiment of biomass pseudo component (cellulose, hemicellulose, and lignin) at varying OTP temperatures and oxygen concentrations. Results showed that more mass of biomass was transferred into the torrefied gaseous and liquid products with OTP temperature and oxygen concentration increasing, remaining less mass in torrefied solid product. The element distribution in biomass pseudo component was optimized after OTP, presenting as the removal of oxygen element and the enrichment of carbon element. The variation of these two elements in hemicellulose after OTP was much higher than that of cellulose and lignin due to the more intensive thermal decomposition reaction in hemicellulose. The chemical compounds in torrefied liquid products from biomass pseudo component were highly differentiated with each other, the anhydrosugars (e.g., levoglucosenone (LGO) and levoglucosan (LG)) and furans (e.g., furfural (FF)) from OTP of cellulose, the furans (e.g., furfural (FF)) and acids (e.g., acetic acid (AA)) from OTP of hemicellulose, the phenols from OTP of lignin. The concentrations of the released gas components during OTP of biomass pseudo component were ranked as CO 2 > CO > H 2 ≈ CH 4. The thermal degradation mechanism of biomass OTP was revealed. [ABSTRACT FROM AUTHOR]

Abstract: There has been much interest in the utilization of biomass-derived fuels as substitutes for fossil fuels in meeting renewable energy requirements to reduce CO2 emissions. In this study, the pyrolysis characteristics of biomass have been investigated using both a thermogravimetric analyzer coupled with a Fourier-transform infrared spectrometer (TG-FTIR) and an experimental pyrolyzer. Experiments have been conducted with the three major components of biomass, i.e. hemicellulose, cellulose, and lignin, and with four mixed biomass samples comprising different proportions of these. Product distributions in terms of char, bio-oil, and permanent gas are given, and the compositions of the bio-oil and gaseous products have been analysed by gas chromatography–mass spectrometry (GC–MS) and gas chromatography (GC). The TG results show that the thermal decomposition of levoglucosan is extended over a wider temperature range according to the interaction of hemicellulose or lignin upon the pyrolysis of cellulose; the formation of 2-furfural and acetic acid is enhanced by the presence of cellulose and lignin in the range 350–500°C; and the amount of phenol, 2,6-dimethoxy is enhanced by the integrated influence of cellulose and hemicellulose. The components do not act independently during pyrolysis; the experimental results have shown that the interaction of cellulose and hemicellulose strongly promotes the formation of 2, 5-diethoxytetrahydrofuran and inhibits the formation of altrose and levoglucosan, while the presence of cellulose enhances the formation of hemicellulose-derived acetic acid and 2-furfural. Pyrolysis characteristics of biomass cannot be predicted through its composition in the main components. [Copyright &y& Elsevier]

The physicochemical characteristics of biomass, as well as the operational conditions of pyrolysis, are crucial factors that influence the production yield of tri-phase products during the pyrolysis of lignocellulosic biomass. Gaussian process regression (GPR) algorithms, being significant machine learning algorithms, are utilized for the prediction of pyrolytic product yields. These algorithms take into account the influence of biomass characteristics and pyrolysis conditions in a comprehensive manner. All of the prediction models exhibit strong performance, with R 2 values exceeding 0.90 and RMSE values below 0.18. The study employed the Partial Dependence Plot (PDP) method to assess the influence patterns of individual features or interactions between two factors on the pyrolysis products. The findings indicate that the ultimate temperature reached during the pyrolysis process is a critical factor in influencing the generation of gaseous byproducts and solid residues. Specifically, higher temperatures are associated with increased production of gaseous byproducts and decreased production of solid residues. The optimal liquid phase yield was achieved at temperatures between 500 °C and 650 °C. In this research, the Particle Swarm Optimization (PSO) algorithm was employed to predict the optimal yields of pyrolysis products. This study offers a novel perspective on predicting product yields from the pyrolysis of lignocellulosic biomass with varying biomass characteristics and under different operational conditions. [Display omitted] • Prediction of pyrolytic products of lignocellulosic biomass using machine learning. • Good prediction performance of the GPR algorithm optimized by the BOA algorithm. • PDP analysis offers valuable insights into the characteristics of pyrolysis. • PSO algorithm for parameter optimization attaining the highest possible yield. [ABSTRACT FROM AUTHOR]

Co-pyrolysis of plastics and biomass is expected to replace traditional petroleum processing to produce BTEX (benzene, toluene, ethylbenzene, and xylenes) on a large scale, which are important chemical raw materials. The introduction of bimetallic catalysts and hydrogen in co-pyrolysis systems is an effective strategy to increase the content of aromatic hydrocarbons in pyrolysis oils, which has not been studied so far. The present study investigated the efficacy of bimetallic catalysts in enhancing aromatization and Diels-Alder reactions in comparison to Mo/ZSM-5. The synergistic interaction between bimetals contributed to the improved selectivity of aromatic hydrocarbons, particularly BTEX. Results revealed that NiMo/ZSM-5 catalysts led to higher aromatics selectivity in liquid oil, whereas FeMo/ZSM-5 resulted in higher BTEX selectivity in aromatic hydrocarbons. Moreover, metal oxide-supported bimetallic catalysts exhibited lower selectivity for aromatic hydrocarbons in liquid oil, despite facilitating higher liquid-oil yield. Among the metal oxide-supported bimetallic catalysts, FeMo/TiO 2 demonstrated the highest selectivity (56%) for aromatic hydrocarbons in liquid oils. The introduction of hydrogen resulted in 100% selectivity of BTEX in aromatic hydrocarbons, thus highlighting the significance of hydrogenation in enhancing the selectivity of BTEX. Combined with the experimental results and literature, a possible reaction mechanism was also proposed. [Display omitted] • The co-hydropyrolysis of plastics and biomass with various catalysts were studied. • Bimetallic catalysts improve the aromatics selectivity in co-hydropyrolysis. • The selectivity of BTEX in aromatic hydrocarbons was up to 94%. • Hydrogen benefits the synthesis of aromatic hydrocarbons during co-pyrolysis. [ABSTRACT FROM AUTHOR]

• Hydropyrolysis vapor upgrading of lignocellulosic biomass. • Obtained C8+ aliphatic hydrocarbons directly. • Three components of biomass transform into long-chain aliphatics by coupling. • C-C coupling reaction with hydroxyalkylation as the main reaction occurred over Ni-Mo/γ-Al 2 O 3. Aviation fuel production is an important direction for biomass utilization, however, the direct transformation of biomass into aviation fuel is a bottleneck in this field. Among all the biomass-to-liquid thermochemical routes, the pyrolysis process can directly produce bio-oil in a continuous industrial manner. Herein, Ni-Mo/γ-Al 2 O 3 catalyst was used to investigate the hydropyrolysis (HP) vapor upgrading (VU) process of lignocellulosic biomass to obtain bio-oil with high selectivity of aviation fuel components. The VU temperature of 300–350℃ was conducive to generating liquid fuel with C8+ aliphatics as the main component of jet fuel. It was indicated that the yield of the oil phase was 6.4 wt% with an HHV of 46.2 MJ/kg, while the selectivity of aliphatics reached 72.6% with C8+ aliphatics was 59.9%. Moreover, it was found that all three components of biomass could be transformed into long-chain aliphatics by coupling reaction. The hydroxyalkylation is the main way and the aldehyde group is the directing group of the carbon-increasing, which was supported by the results of the quantum chemical calculation. Further, the reaction network for the HP-VU process of lignocellulosic biomass with C8+ aliphatics as the main product was proposed to provide a theoretical understanding of the carbon-increasing in biomass hydropyrolysis. [ABSTRACT FROM AUTHOR]

Autothermal pyrolysis that generates in situ heat is a promising way to convert lignocellulosic biomass into value-added products. Autothermal pyrolysis of pinewood under different oxygen concentrations (i.e., 3 %, 5 %, and 10 % O 2) was performed in this work. The results showed oxygen addition significantly decreased the selectivity of anhydrosugars in bio-oil by 41.90% at most. Micropores formation in the char was enhanced in the autothermal pyrolysis, and the BET surface area of char obtained under 10 % O 2 was 21.9045 m2·g−1. Fraser-Suzuki function was adopted to deconvolute the biomass autothermal pyrolysis process into four pseudo-reactions; namely three degradation reactions of hemicellulose, cellulose, and lignin and a combustion reaction of char residues. The activation energies of three pseudo-degradation reactions decreased after oxygen was introduced, whereas the activation energy of pseudo-combustion reaction of char increased from 69.08 to 88.34–127.47–163.13 kJ·mol−1 as oxygen content increased from 3 % to 10 %. Three major thermodynamic parameters of activation for each pseudo-reaction were also calculated. Δ S ‡ results indicated that three pseudo-degradation reactions at the transition state became more ordered at higher oxygen concentration, whereas pseudo-combustion of char showed an opposite trend. The results obtained from this study provide systematic and precise fundamental information for biomass autothermal pyrolysis scale-up. [Display omitted] • Autothermal pyrolysis slightly decreased bio-oil and char yield. • O 2 presence enhanced formation of micropores in char. • Fraser-Suzuki function deconvoluted global process into several pseudo-reactions. • Char combustion reaction had the lowest E α and it increased with O 2 addition. • More O 2 led to more organized activated complexes formed from degradation reactions. [ABSTRACT FROM AUTHOR]

Torrefaction is a low-temperature process considered as an effective pretreatment technique to improve the grindability of biomass as well as enhance the production of aromatic hydrocarbons from Catalytic Fast Pyrolysis (CFP). This study was performed to understand the effect of torrefaction temperature on structural changes in the lignin macromolecule and its subsequent influence on in-situ CFP process. Lignin extracted from southern pine and switchgrass ( via organosolv treatment) was torrefied at four different temperatures (150, 175, 200 and 225 °C) in a tubular reactor. Between the two biomass types studied, lignin from pine appeared to have greater thermal stability during torrefaction when compared with switchgrass lignin. The structural changes in lignin as a result of torrefaction were followed by using FTIR spectroscopy, solid state CP/MAS 13 C NMR, 31 P NMR spectroscopy and it was found that higher torrefaction temperature (200 and 225 °C) caused polycondensation and de-methoxylation of the aromatic units of lignin. Gel permeation chromatography analysis revealed that polycondensation during torrefaction resulted in an increase in the molecular weight and polydispersity of lignin. The torrefied lignin was subsequently used in CFP experiments using H + ZSM-5 catalyst in a micro-reactor (Py-GC/MS) to understand the effect of torrefaction on the product distribution from pyrolysis. It was observed that although the selectivity of benzene-toluene-xylene compounds from CFP of pine improved from 58.3% (torrefaction temp at 150 °C) to 69.0% (torrefaction temp at 225 °C), the severity of torrefaction resulted in a loss of overall aromatic hydrocarbon yield from 11.6% to 4.9% under same conditions. Torrefaction at higher temperatures also increased the yield of carbonaceous residues from 63.9% to 72.8%. Overall, torrefying lignin caused structural transformations in both type of lignins (switchgrass and pine), which is ultimately detrimental to achieving a higher aromatic hydrocarbon yield from CFP. [ABSTRACT FROM AUTHOR]

Co-pyrolysis of biomass with waste tire, a hydrogen-rich material, can both improve the quality of bio-oil and mitigate the environmental issue caused by the disposal of waste tires. In this study, co-pyrolysis of corn stover and waste tire was firstly performed in a micro pyrolyzer, and positive synergistic effects were observed, promoting the production of hydrocarbon compounds. Additionally, the kinetics of co-pyrolysis of corn stover and waste tire were investigated. Due to the complexities of the co-pyrolysis process, the global process was divided into reactions of seven pseudo-components using the Fraser-Suzuki deconvolution function. The deconvolution results presented a good fit with experimental results. The activation energy of each pseudo-component was calculated using Kissinger-Akahira-Sunose (KAS), Flynn-Wall-Ozawa (FWO), and Friedman methods. Activation energy of each pseudo-component calculated from above mentioned methods did not greatly varied. Pseudo-component additives in waste tire with low thermal stability had the lowest activation energy (118.21–127.10 kJ/mol), and lignin in corn stover and synthetic rubbers (SR) in waste tire showed high activation energies since they are more thermally stable. The reaction mechanism was then determined using the master plot method. The results of the study are expected to provide more accurate basic information for further scale-up of the co-pyrolysis process. [Display omitted] • Synergistic effects existed in co-pyrolysis of corn stover and waste tire. • Addition of waste tire promoted the hydrocarbons production for co-pyrolysis. • Fraser-Suzuki model successfully deconvoluted DTG curves into 7 pseudo-components. • Kinetic triplets were determined for co-pyrolysis of corn stover and waste tire. [ABSTRACT FROM AUTHOR]

This work illustrates how the Tandem micro-Reactor (TMR), when interfaced to a GC–MS, facilitates the rapid characterization of virtually any material: gases, liquids and solids. A TMR has two independently controlled micro-reactors in series. Each micro-reactor has three heating modes: isothermal (up to 900 °C), multi-linear (e.g., 100–400 °C at 20 °C/min) and distinct temperature steps (e.g., 100 °C, 200 °C, etc.). The TMR can be used for both Evolved Gas Analysis (EGA) and detailed component analysis. Three examples illustrate how the TMR-GC–MS can be configured to differentiate or identify virtually any material. (1) Lignin, oak, bagasse and cellulose are easily differentiated using EGA–MS – each material is analyzed directly by simply weighing the sample (<75 mesh) into the sample cup. (2,3) The temperature dependence of ethanol and methanol transformations to ethylene and propylene, respectively, are presented using an online, real-time configuration. The ethylene transformation is also performed using a series of ethanol injections at distinct catalyst temperatures. Lastly, regeneration of the catalyst’s surface is performed in-situ, which improves laboratory productive as well as elevating the precision of the data. [ABSTRACT FROM AUTHOR]

• Torrefaction combined with catalytic pyrolysis is proposed to selectively convert the biomass into aromatic hydrocarbons. • Degradation of hemicellulose and demethoxylation on phenols occur during torrefaction and catalytic reactions, respectively. • Cedarwood torrefied at 250 °C and 5% Ni and Mo2N loaded HZSM-5 are suitable for generating monocyclic aromatic hydrocarbons. • Polycyclic aromatic hydrocarbons are inhibited resulting from the reduction ability of the modified catalyst. The present study proposes biomass torrefaction combined with catalytic pyrolysis to simplify the liquid products and selectively generate aromatic hydrocarbons. Cedarwood was selected as the representative biomass sample. The torrefaction of cedarwood at 250ºC and 300°C (TB250 and TB300) was carried out to determine the solid product yield and its composition. It was shown that TB250 yielded the highest lignin feedstock and the yield of acetic acid was decreased to 1.88 %. Different transition metals (Ni/Cr) and Mo 2 N modified HZSM-5 catalysts with different Si/Al ratios were prepared for catalytic pyrolysis. Pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments were performed to evaluate the effects of several factors on the final aromatic hydrocarbons yields. The results indicated that with a pyrolysis temperature of 700°C, a catalyst-to-biomass ratio of 5, and 5% Ni-Mo2N/HZSM-5 (Si/Al ratio of 25) catalyzed, the yields of benzene, toluene and xylene could be increased to 2.10 %, 3.94 % and 5.54 %, respectively. Resulting from the excellent reduction ability of the modified catalyst, the yields of naphthalene and methylnaphthalene were reduced to 2.58 % and 0.70 %, respectively. [ABSTRACT FROM AUTHOR]