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This paper takes the catalytic cracking unit of a petrochemical industry as an example to explore the effects of blending hydrogenated tail oil on the distribution and quality of catalytic cracking products, and analyzes the reasons. The results showed that blending hydrogenated tail oil can significantly reduce the output of dry gas and oil slurry. Every increase of 1 ton of hydrogenated tail oil refining, the output of oil slurry decreases by 0.14 tons, dry gas decreases by 56 m³, and gasoline output increases by 0.26 tons. The blending of hydrogenated tail oil will reduce the aromatic hydrocarbon content in gasoline components, decrease the density of gasoline components, and lower the distillation temperature. As the blending amount of hydrogenated tail oil increases, the C3 content in the liquefied petroleum gas decreases and the C4 content increases . This is attributed to the fact that the blending of hydrogenated tail oil inhibits the deep reaction of catalytic cracking, reduces the generation of C3 and below components and deep cracking products such as slurry, and increases the yield of liquids above C4. As the blending amount of hydrogenated tail oil increases, C3 and C4 components become the boundary line for the impact of hydrogenated tail oil blending on the depth of catalytic cracking reaction. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Refinery Engineering is the property of Petroleum Refinery Engineering Editorial Office 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.)

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

The present study uncovered the effect of pyrolysis temperature (400, 500, 600, and 700 °C), and biomass-to-plastic ratio (100:0, 25:75, 50:50, 75:25, 0:100) on the product distribution and synergistic effect during co-pyrolysis of palm kernel shell (PKS) and medical bottle (MB). The highest bio-oil yield of 65.93 wt% was attained at 500 °C and PKS:MB ratio of 25:75. To determine the synergistic effect, the product distributions (yield and chemical composition) were compared with those obtained from pyrolysis of individual components. The positive synergistic effect on the production of hydrocarbons and inhibition of acids were most dominant at PKS:MB ratio of 75:25. The presence of PKS-derived oxygen radicals and hydrogen abstraction from MB can accelerate the formation of hydrocarbons via secondary cracking and deoxygenation reaction. The produced oil at PKS:MB ratio of 50:50 showed better characteristics compared to PKS-derived oil which contains higher carbon (45 % higher), and hydrogen content (66 % higher), and lower oxygen content (71 % lower).

Copyright of Low-Carbon Chemistry & Chemical Engineering is the property of Low-Carbon Chemistry & Chemical Engineering Editorial Office 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.)

It needs to be improved the conversion efficiency and stable operation of conventional pyrolysis with high-temperature flue gas heating (HFH). Herein, a new radiative heating (RH) pyrolysis method is proposed. Experimental studies are carried out on a self-made radiation pyrolysis pilot plant to investigate the effects of different factors (pyrolysis final temperature, residence time, and carrier gas volume) on product distribution. The results show that with the increase of pyrolysis temperature, the yield of the gas phase consistently increases, and the proportion of CH4 and H2 in the pyrolysis gas reaches 62.31% at 700 °C. The yield of the liquid phase increases and then decreases. The recovery rate of pyrolysis oil achieves 68.07% when the pyrolysis temperature is 600 °C with main components of ketones and unsaturated hydrocarbon compounds. The yield of the solid phase consistently decreases. The RH in this work generates more pyrolysis gas in the pyrolysis process and alleviates the effects of fouling layers on the continuous operation of the equipment which has guiding significance for the efficient resource utilization of oil sludge. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Bioprocess Engineering is the property of Chinese Journal of Bioprocess Engineering Editorial Office 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.)

Existing performance analysis of wireless systems based on reconfigurable intelligent surfaces (RIS) over fading channels has primarily focused on providing statistical insights into the sum and product of random variables, typically represented as a single-variate Fox-H function. A research gap exists for an exact performance analysis when the statistical characterization of wireless systems, including RIS-assisted systems, requires more than a single-variate Fox-H function. In such cases, incorporating a multivariate representation becomes imperative, particularly when addressing generalized fading models and channel estimation errors, even with simpler one-parameter fading models. This paper introduces a novel approach to derive the distribution of the sum and product of independent and nonidentical distributed (i.ni.d) random variables characterized by the multivariate Fox-H function. We also establish a general framework for an exact analysis of ergodic capacity and average signal-to-noise ratio (SNR) when the multivariate Fox-H function describes the statistics of the channel. Applying the derived results, we conduct an exact performance analysis of outage probability and ergodic capacity, exemplified by RIS-assisted communication over Rician fading channels with imperfect phase compensation and channel estimation errors. Computer simulations validate the exact analysis and illustrate the performance of the RIS-assisted system under various practically relevant scenarios, enhancing the overall performance assessment.

This paper presents empirical evidence and develops a repeated-game model for manufacturer–retailer relationships and demonstrates that these relationships limit the impact of regulations. Industry practitioners often emphasize the importance of manufacturer–retailer relationships in product distribution. In this paper, I formalize the industry's notion of a relationship with a repeated game framework and study its impact in the heavily regulated hard cider market. I present evidence that retailers and leading manufacturers coordinate with and offer preferential treatment to each other when setting assortments and wholesale prices. Based on this evidence, I develop a repeated game–based model to estimate each pair's coordination, which is linked to the manufacturer's performance at the retailer in the broader beer market. The results show the relationships increase new cider availability by 17.5% and 5.1%, respectively, for Anheuser-Busch InBev and MillerCoors, the two leading brewers. The relationship's effect is determined jointly by the degree of assortment distortion and the reduction in double marginalization. Although these relationships could improve welfare, they imply that current regulations in the alcoholic beverage industry fail to generate a level playing field for every manufacturer. History: Puneet Manchanda served as the senior editor. Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mksc.2023.1445. [ABSTRACT FROM AUTHOR]

Purpose: Process digitization and artificial intelligence are the needs of today's industry. The Fourth Industrial Revolution along with the concept of Industry 4.0 provides a huge opportunity for the development of many industries. Industry 4.0 imposes high demands on production and logistics in cyber-physical systems. Therefore, the primary objective of this publication is to present the concept of Industry 4.0, with particular emphasis on the impact of its technological solutions on the process of distribution of industrial goods. The challenges and benefits of the concept of Industry 4.0 are also presented in the article. Design/methodology/approach: The work consists of two parts, the review of literature and the research part. The theoretical part presents the impact of technological solutions on the evolution of the distribution process. The empirical part focuses on the importance of technologicalsolutions in the segment of Polish steel product distributors. In Poland, 9.7 million tons of steel is produced on average annually. In the world, according to the analyzes of the World Steel Association, 1781.5 million tons of steel was produced in 2022. Steel is an important construction and industrial material used in the production of cars, machines, ships, appliances, etc. Research was realized in Polish sector of companies. The questionnaire was build according the structure of Industry 4.0 based on pillars. In the questionnaire was used Likert scale from 1 to 5 with 5 being the highest. Findings: Steel sector companies are aware of the importance of the technology of Industry 4.0 in improving the course of the process and communication with the market. The respondents highly assessed the importance of the pillars of Industry 4.0 in the processes of storage and distribution of steel products, most often choosing 4 in the Likert scale from 1 to 5. Originality/value: Studies presented in this paper are strongly linked to the current concept of industrial development, which is Industry 4.0. [ABSTRACT FROM AUTHOR]

The reactions of limonene with various free radicals (•OCH3, •OBr, •SH, •OOH, and •OOCH3) were investigated along the 273.15–312.15 K temperature range. To that purpose the density functional theory was used, at the M06‐2X/6–311+g(d,p) level. Two reaction mechanisms, hydrogen atom transfer (HAT) and radical adduct formation (RAF) were considered. It was found that the relative reactivity of the studied radicals toward limonene is: •SH > •OBr > •OCH3 > •OOH > •OOCH3. HAT was identified as the dominant mechanism for •OOH and •OOCH3, while RAF contributes the most to the reactions involving •OCH3, •OBr, and •SH. The obtained Arrhenius expressions are: k(•OCH3) = 1.58 × 10−13 e−1.59/RT, k(•OBr) = 3.55 × 10−12 e+1.82/RT, k(•SH) = 3.30 × 10−11 e+0.79/RT, k(•OOH) = 1.33 × 10−15 e−5.99/RT, and k(•OOCH3) = 5.88 × 10−17 e−6.26/RT. According to them, the reactions of •OBr and •SH become slower as temperature rises from 273.15 to 312.15 K, while for the other radicals the reactions rate increases with temperature. The subsequent tropospheric fate of the most abundant •OBr adduct was also investigated in the same temperature range, considering O2 addition to this radical (step 2) and the reaction of the peroxyl radical yielded in this step 2 with NO. The latter is predicted to take place in two steps: the NO addition (3a) and the NO2 elimination (3b). The corresponding Arrhenius expression are k2 = 3.56 × 10−15 e+1.43/RT and k3b = 1.35 × 1014 e−31.65/RT. Step 3a was found to be barrierless. To our best knowledge, all the data provided here is reported for the first time. Thus, it would hopefully contribute to enhance the knowledge necessary for the full understanding (and accurate modeling) of the troposphere. [ABSTRACT FROM AUTHOR]

This article considers Inverse Pareto and Exponential distributions to create the distribution of the product. The researchers derived its properties, such as; survival functions and hazard functions, and used the model criterion such as Sum Square Error (SSE), Akaike Information Criterion (AIC), and Bayesian Information Criterion (BIC) in estimating the parameters for deriving the best joint distribution between monthly precipitation and temperature in the Philippines from 1974 to 2013. The results showed that considering the monthly precipitation and temperature data, the distribution of the product of Inverse Pareto and Exponential outperformed the other existing distribution of the product.

Though antitrust authorities have historically focused on prices in merger analyses, there is now growing interest in the impact of mergers on non‐price outcomes. In this paper, we examine the effect of horizontal mergers on product variety in the U.S. beer industry. Our difference‐in‐differences analyses provide evidence that acquired firms increase variety available to consumers by expanding into new markets, while reducing the variety of products sold in their existing markets. Back of the envelope calculations suggest that in aggregate, these acquisitions have a net positive effect on product variety. [ABSTRACT FROM AUTHOR]

Fischer-Tropsch synthesis (FTS) is a widely recognized process that catalytically converts syngas into higher hydrocarbons and oxygenates, which are ultimately upgraded into transportation fuels and chemicals. Effective temperature control and heat dissipation are crucial considerations due to the exothermic nature of the FT reaction. Underutilization of the catalytic bed is another challenge in fixed-bed reactors. The implementation of a multilayered catalytic bed, with the catalytic activity in an ascending order, has shown positive effects in addressing these issues. It mitigates adiabatic temperature rise, reduces the maximum reactor temperature, and minimizes catalyst deactivation at high temperatures. Moreover, this multilayered bed effectively addresses the underutilization issue by ensuring optimal utilization of the entire bed as the catalytic activity transitions from one layer to another during the reaction. Layers with a higher cobalt loading remain active until the completion of the reaction, resulting in minimal fluctuations in CO conversion. To achieve uniform temperature profiles, catalytic activities, and product distributions in all reactor tubes in a multitubular reactor, it is imperative to maintain consistent reaction conditions, utilize the same catalyst loading in all tubes, employ an appropriate heating system, and implement an efficient cooling system to dissipate the heat generated by the exothermic reaction. Furthermore, investigations into the properties of the used catalysts after the reaction indicate that catalyst deactivation primarily occurs due to the deposition of FT products on the catalyst surface and pores and blockage of active cobalt sites, and sintering of cobalt particles. [Display omitted] • Multilayered catalytic bed of Co/Al 2 O 3 catalysts for Fischer–Tropsch synthesis in multitubular fixed-bed reactor. • Multilayered catalytic bed reduced the maximum adiabatic temperature rise during the reaction. • Utilization of catalytic bed increase by using the multilayered catalytic bed in the reactor. • Accumulation of FT products and sintering of cobalt particles are the main catalyst deactivation mechanisms. [ABSTRACT FROM AUTHOR]

Computational chemistry, with considerable effort, was used to elucidate the reason for regioselectivity (12:1 distal:proximal product distribution) in a published Wacker oxidation of internal alkenes with a homoallylic lactam ring. Such a distribution is reproduced by a non-chelating reaction pathway; chelated intermediates are found to be too high in energy. Despite much speculation of chelation effects in the literature, this particular result is most probably an antiperiplanar field effect with no chelation. Partial charge data are provided to support the proposed antiperiplanar effect. The great care needed in modelling Wacker oxidations is emphasized, but optimism is offered that its various product mysteries can be elucidated on a case-by-case basis. [ABSTRACT FROM AUTHOR]

In order to improve the efficiency of oil shale pyrolysis and the utilization value of semi-coke, this paper co-pyrolyzed Huadian oil shale and waste tire.The weight loss behavior, product yield and composition properties of co-pyrolysis were investigated by thermogravimetric analyzer and aluminum retort reactor.The synergistic effect was analyzed based on the difference between experimental and calculated values.The results show that co-pyrolysis can promote the release of volatile matter, the actual weight loss is higher than the calculated value at 500 ℃, and reaches the maximum value of 2.86 % when the proportion of waste tire is 80 %.The mixed pyrolysis of oil shale and waste tire has the effect of "increasing oil and reducing water".When the waste tire accounts for 50 %, the actual oil yield is 32.91 %, which is 1.5 % higher than the calculated value, and the actual water yield is 1.20 % to 1.77 % lower than the calculated value.Meanwhile, the content of heavy components with boiling point higher than 350 ℃ in the pyrolysis oil increases.There is higher yield of C1~C4 hydrocarbons from waste tire pyrolysis, and the calorific value of semi-coke is up to 30.43 MJ/kg.Co-pyrolysis can also improve the calorific value of pyrolysis gas and semi-coke.

Two-step pyrolysis (TSP) of cellulose, hemicellulose, and lignin; the three-component cross-coupling samples; and the acid-washed walnut shell (AWS) were carried out by a pyrolysis–gas chromatography/mass spectrometry (Py-GC/MS) to investigate the effects of components and their proportions on the TSP of biomass. The results showed that different components dominated the formation of different products. Cellulose generated more furans and carbohydrates in both the first (S1) and second steps (S2). Hemicellulose achieved higher selectivity of ketones, acids, and alcohols in S1, and higher selectivity of hydrocarbons in S2. Lignin mainly produced phenols in S1, and hydrocarbons and phenols in S2. The increase of holocellulose (hemicellulose and cellulose) improved the contents of aldehydes, ketones, furans, acids, and alcohols but reduced the content of phenols in S1. In S2, more holocellulose increased the contents of aldehydes, ketones, and acids, but decreased the contents of phenols, hydrocarbons, and alcohols. The generation of carbohydrates was strongly inhibited in S1 by hemicellulose and lignin. More cellulose improved the contents of aldehydes, acids, and furans in S1, and increased the content of ketones but reduced the content of acids in S2. Hemicellulose facilitated the generation of hydrocarbons, but inhabited the produce of carbohydrates in S2. The small amount of the low-content components (protein, alkali and alkaline earth metals, etc.) and the connection structure of the components resulted in the significant difference in the pyrolysis reactions and product distribution of AWS and the mixed sample with corresponding component proportion. Therefore, more influence factors, such as the low-content components, the connection structure of the components, and different pyrolysis conditions, should be considered in the near future to investigate the interactions on the two or more components in TSP. [ABSTRACT FROM AUTHOR]

It is important to clarify the distribution of pyrolysis products from lignocellulosic biomass for its thermal transformation to produce high-quality bio-oil. Influences of the reaction temperature and catalysts on the pyrolysis product distribution from aspen wood (AW) and rice husk (RH) were studied by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The difference in components from the lignocellulosic biomass results in different pyrolysis characteristics of the biomass raw materials. The reaction temperature significantly influences the product distribution from AW and RH pyrolysis. In all AW catalysis experiments, acids (8.35%), ketones (3.79%), phenols (4.73%), and esters (1.50%) have the lowest content while carbohydrates (48.75%) demonstrate the highest content when taking zinc chloride (ZnCl2) as the catalyst; the HZSM-5 molecular sieve (HZSM-5) promotes the generation of esters (7.97%) and N-compounds (22.43%) while inhibiting production of aldehydes (2.41%); addition of an MCM-41 molecular sieve (MCM-41) is conducive to increasing the contents of aldehydes (21.29%), furans (5.88%), ketones (22.30%), acids (20.46%), and hydrocarbons (4.85%), while reducing the contents of alcohols (0) and carbohydrates (0). In all RH catalysis experiments, the addition of ZnCl2 helps increase the content of carbohydrates (39.16%) and decrease the contents of ketones (3.89%), phenols (5.20%), alcohols (2.34%), esters (1.13%), and N-compounds (3.09%); when applying HZSM-5 as the catalyst, hydrocarbons (18.28%) and alcohols (6.66%) reach their highest content while acids (13.21%) have the lowest content; MCM-41 promotes the generation of aldehydes (25.33%) and furans (5.55%) while inhibiting that of carbohydrates (1.42%). [ABSTRACT FROM AUTHOR]

Effective management is necessary due to the substantial environmental challenges arising from the significant annual biosolids production in wastewater treatment plants. Hydrothermal liquefaction (HTL) provides a viable solution for transforming biosolids into renewable crude oil. However, further investigation is required to understand the HTL of biosolids. An examination of HTL in a small-scale batch reactor revealed that both the HTL reaction conditions and biosolids content influence the yield of renewable crude oil, which ranged from 21% to 26%, where the highest yield was achieved at 250 °C, 20 min. However, the highest extractible renewable crude yields were achieved at 350 °C and 40 mins due to the high amount of the low boiling material at a low boiling point. The fractions of renewable crude oil were influenced by both the HTL reaction conditions and the biosolids content. Based on the boiling point, biosolids with a high-lipid content produced the maximum potential gasoline and naphtha-like yield, while high-carbohydrate biosolid content generated the highest potential kerosene-like yield. All biosolid samples demonstrated significant potential for gas oil-like, wax, and lubricating oil-like fractions. Additionally, A developed bulk kinetic model to predict the product fractions showed the trends in product fractions with various reaction times and temperatures. • The products' yields and quality affected by biomass type and HTL conditions. • Boiling point profiles of renewable crude determined by TGA analysis. • Biosolids with high lipid and protein content increase the renewable crude yield. • Desirable crude fractions depend on both biosolids composition and HTL conditions. [ABSTRACT FROM AUTHOR]

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

Climate change issues are calling for advanced methods to produce materials and fuels in a carbon–neutral and circular way. For instance, biomass pyrolysis has been intensely investigated during the last years. Here we review the pyrolysis of algal and lignocellulosic biomass with focus on pyrolysis products and mechanisms, oil upgrading, combining pyrolysis and anaerobic digestion, economy, and life cycle assessment. Products include oil, gas, and biochar. Upgrading techniques comprise hot vapor filtration, solvent addition, emulsification, esterification and transesterification, hydrotreatment, steam reforming, and the use of supercritical fluids. We examined the economic viability in terms of profitability, internal rate of return, return on investment, carbon removal service, product pricing, and net present value. We also reviewed 20 recent studies of life cycle assessment. We found that the pyrolysis method highly influenced product yield, ranging from 9.07 to 40.59% for oil, from 10.1 to 41.25% for biochar, and from 11.93 to 28.16% for syngas. Feedstock type, pyrolytic temperature, heating rate, and reaction retention time were the main factors controlling the distribution of pyrolysis products. Pyrolysis mechanisms include bond breaking, cracking, polymerization and re-polymerization, and fragmentation. Biochar from residual forestry could sequester 2.74 tons of carbon dioxide equivalent per ton biochar when applied to the soil and has thus the potential to remove 0.2–2.75 gigatons of atmospheric carbon dioxide annually. The generation of biochar and bio-oil from the pyrolysis process is estimated to be economically feasible. [ABSTRACT FROM AUTHOR]

Bimetallic Pt3Eu/C, Pt3La/C, and Pt3Ce/C electrocatalysts have been prepared, characterized, and tested for ethanol electro-oxidation (EEO). The materials were synthesized by chemical reduction with NaBH4, rendering nanosized particles with actual compositions close to the nominals and no alloy formation. X-ray photoelectron spectroscopy (XPS) confirmed that the auxiliary rare-earth metals were present on the surface in oxide form. The electrochemical analyses in acid and alkaline EEO evidenced that, compared to Pt/C, the addition of rare earth metals in the form of oxides reduced the onset potential, increased the current density, and enhanced the stability. The results were fully confirmed in the DEFC single-cell measurements. Finally, the presence of rare earth metals in the oxidized form increased the percentage of acetic acid as the final product, making the electrocatalysts more selective and efficient than Pt/C, where acetaldehyde was the main product. [ABSTRACT FROM AUTHOR]

The self-healing effect of cracks is an important basis for evaluating the level of functional recovery of materials. To realize the comprehensive evaluation of the full-section repair effect of cracks in cement-based materials, research on crack self-healing evaluation methods based on contact resistance theory had been carried out, including the selection and optimization of conductive materials, the optimization of test parameters, and the derivation of calculation methods. The results show that 0.3% volume dosage carbon fiber can effectively reduce the resistivity of cement-based materials and simultaneously improve mechanical properties. The measured voltage has no significant effect on the resistivity. The resistivity gradually decreases with the increase of contact pressure. The self-healing process of cracks is the process of changing the contact form of crack surface, which is also accompanied by changes in the contact resistance. According to this, a quantitative calculation formula for contact resistance and self-healing effect can be established. This method is only related to the accumulation of repair products on the crack surface, and is not affected by the spatial distribution of the products. The conclusions provide a reference for the quantitative characterization of the self-healing effect of cement-based materials. [ABSTRACT FROM AUTHOR]

The product partition model (PPM) is widely used for detecting multiple change points. Because changes in different parameters may occur at different times, the PPM fails to identify which parameters experienced the changes. To solve this limitation, we introduce a multipartition model to detect multiple change points occurring in several parameters. It assumes that changes experienced by each parameter generate a different random partition along the time axis, which facilitates identifying those parameters that changed and the time when they do so. We apply our model to detect multiple change points in Normal means and variances. Simulations and data illustrations show that the proposed model is competitive and enriches the analysis of change point problems. [ABSTRACT FROM AUTHOR]

Plastic waste and scrap tires (ST) have now become pollution that harms the environment in various cities around the world if not managed properly. As pollutants, the two types of waste are actually very interesting to manage because they contain hydrocarbon elements so that they can be processed and have the potential to become alternative fuels. This study aims to determine the effect of co-pyrolysis of scrap tires (ST) and polypropylene (PP) plastic on the distribution of products in the form of oil and char/charcoal. The pyrolysis process was carried out at a temperature of 450℃ for 90 minutes using a fixed bed pyrolysis reactor with ST:PP mixing variations, namely 9:1, 8:2, 7:3, 6:4, and 5:5. The maximum pyrolysis product yield in the form of oil as much as 40.7 Wt% was obtained at a 6:4 mixing variation followed by a 7:3 (36.7 Wt%) mixing variation, then a 5:5 variant (36 Wt%), after that an 8:2 variant (34.3 Wt%) and the last is the 9:1 mixing variation with a total of 28.3 Wt%. For the maximum pyrolysis product in the form of char as much as 42.6 Wt% obtained at 9:1 mixing variation followed by 7:3 mixing variation (41 Wt%) after that 8:2 variant with 38.7 Wt%, then 6:4 with the amount of 27.7 Wt%, and the last is the mixing variation of 5:5 to obtain the char result of 18.3 Wt%. Physical properties of pyro-oil in the form of density and calorific value will also be shown in this study.

This paper investigates separate pyrolysis of corn stalk(CS)and polypropylene(PP)and co-pyrolysis of CS and PP over Zn-Al co-modified MCM-41 to produce aromatics, and the product distribution of catalytic co-pyrolysis of CS and PP was studied based on a rotating bed reactor. The results showed that the product contents and composition were significantly influenced in the presence of catalysts. Zn and Al showed a certain synergistic effect, under the catalysis of MCM-41 co-modified by Zn with mass fraction of 1% and Al with mass fraction of 3%, and the maximum proportions of aromatics(24.31%)and the minimum production of oxygenated compounds(12.37%)were obtained. In the experiment of catalytic co-pyrolysis of CS and PP in rotating bed, with the increase of pyrolysis temperature(500—800 ℃), the yield of bio-oil decreased gradually. The decrease of olefins and oxygenates in bio-oil significantly increased the content of aromatic hydrocarbons. With the increase of catalyst dosage(1:0—1:10), the yield of bio-oil reduced gradually. The contents of aromatic hydrocarbons in bio-oil increased obviously, while the contents of olefins and oxygenates decreased. With the increase of rotating speed(0—20 r/min), the yield of bio-oil first decreased and then increased. The extreme values of aromatics, olefins, and oxygenates in bio-oil were all obtained at 15 r/min. [ABSTRACT FROM AUTHOR]

Catalytic fast pyrolysis (CFP) for biomass treatment is a research hotspot but there is little information about the difference between the in situ and ex situ methods. In present work, the Ni–Fe/CaO–Al2O3 catalysts with different Ni/Fe ratios have been synthesized by coprecipitation method, and the product distribution about the Chinese herb residue (CHR) catalytic fast pyrolysis by in situ and ex situ methods in a quartz tube reactor system has been investigated. The results show that the CFP pyrolysis would upgrade the quality of bio-oil but decrease the yields, no matter in situ or ex situ CFP process. During the in situ CFP process, heteroatoms may be absorbed by the catalyst support and cannot be transferred to the bio-oil, but the results of ex situ CFP are the opposite. In addition, the ex situ CFP reaction significantly increases the content of aromatic hydrocarbons. As to the gas products' distribution, the effect of Fe in catalysts to promote CH4 formation is reflected in in situ CFP process, while the promotion effect of H2 generation for Ni added in catalyst is mainly reflected in ex situ CFP process. However, due to the high reaction temperature (800 °C), the adsorption of CO2 by CaO support is not particularly significant. The possible mechanism of CHR in CFP process has also been summarized for understanding the process of in situ and ex situ CFP, and this study may provide a choice or reference for CHR treatment. [ABSTRACT FROM AUTHOR]

On the multi-functional fluidized catalytic pilot plant, the experimental comparison was carried out according to different reaction modes, and the evaluation indexes PE and Phe of catalytic cracking propylene production efficiency were put forward. The influence of reaction modes was analyzed from the aspects of alkanes, thermal cracking, hydrogen transfer, propylene production efficiency indexes, etc. The results show that compared with the traditional riser + fluidized bed reaction mode, the HCP (high efficiency catalytic cracking for more propylene) reaction mode with "conveyor bed and circulating fluidized bed in series and staged control" can significantly reduce the yield of dry gas and coke, reduce the yield of alkanes, and improve the efficiency of propylene production. HCP reaction mode can effectively inhibit thermal cracking reaction, hydrogen transfer reaction and single molecule cracking reaction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Carbon removal rate-limiting for Fe-carbide in the Fischer-Tropsch (FT) reaction. • C deposits decrease FT activity and increase CH 4 selectivity. • SSITKA investigations used as function of amount of C deposits. • Slow sites mainly responsible for CH 4 formation via MvK mechanism. • Higher H 2 /CO ratio or total pressure removes C deposits and decreases deactivation. A well-known observation in the Fe-catalyzed Fischer-Tropsch (FT) reaction is that Fe-carbide catalysts deactivate due to carbon deposition. In comparison, the influence of such carbon deposits on the product distribution has been less widely reported. The present work investigates the relationship between the kinetics of the FT reaction for a carburized Raney-Fe model catalyst and the composition of the catalytic surface with a focus on carbon deposits. The deposition of carbon during the ongoing FT reaction at low pressure decreases the FT activity and increases the CH 4 selectivity. Steady-state transient isotopic kinetic analysis (SSITKA) at low pressure shows that the buildup of C deposits affects fast CO conversion sites on the Fe-carbide surface, mainly responsible for C C coupling via a Langmuir-Hinshelwood mechanism, more than slow sites that mainly produce CH 4 via a Mars-Van Krevelen mechanism. Hindrance of migration of chain-growth monomers by C deposits decreases the amount of longer hydrocarbons. Nevertheless, SSITKA shows that C 2 products form faster, which is likely since their formation increasingly depends on monomers formed at proximate CO dissociation sites when the amount of carbon deposits increases. Carbon deposition can be suppressed and reversed by increasing the H 2 /CO ratio at constant pressure or by increasing the total pressure at constant H 2 /CO ratio. As such, the FT performance can be stabilized by operating at elevated pressure, even if initially the reaction was started at low pressure. Nevertheless, prolonged operation at low pressure leads to a less reactive character of the C deposits that cannot be removed anymore during high-pressure operation. [ABSTRACT FROM AUTHOR]

• Pyrolysis of bituminous coal under high-temperature thermal shock is studied. • Relationship between pyrolytic gas product and particle morphology was analyzed. • Carbon matrix purification is a successive process linear with temperature rise. • Graphitization of coal carbon structure was found to exist an abrupt temperature. The current investigation aims to reveal the pyrolysis characteristics and particle microstructure evolution of bituminous coal under the high-temperature thermal shock. In the experimental temperatures, the purification of carbon matrix in the coal char is a successive process linear on temperature. In contrast, the graphitization process of carbon structure existed a transition temperature (1600 ℃). Specifically, the range of 1000–1500 ℃ is critical for the transformation of amorphous carbon to disordered graphite, but the growth of graphite microcrystals was minimally affected. While the range of 1600–1900 ℃ is critical for the formation of the graphite-like carbon structure. It is characterized by the release of defective structures such as oxygen-containing functional groups, and a significant increase in crystal size. Although beneficial for the subsequent study of carbon materials, the ordered graphite transformation led to the deactivation of char. The pyrolysis behavior study under thermal shock insight into the thermal behavior of coal char in high-temperature furnaces, as well as a new idea for the clean utilization of coal resources. [ABSTRACT FROM AUTHOR]

• Reducibility of Ni/ZSM-5 is lowered by the abundance of acid sites. • LA hydrogenation is favored by Ni/ZSM-5 with high Si/Al molar ratio. • Tailoring acidic and metallic function of Ni/ZSM-5 can steer the product distribution. • Investigation of catalytic mechanism of LA hydrogenation via microkinetics. • An innovative mathematical description of sorption energy barriers and (de)sorption kinetics. The study examines Ni/ZSM-5 catalysts in vapor phase hydrogenation of levulinic acid (LA) under continuous flow conditions (ambient pressure, 210–250 °C). Advanced characterization revealed the interplay between Al and Ni. This was further reinforced by new approach of microkinetic modeling, which demonstrates a pioneering work on mathematical description of pulse H 2 sorption, TPD kinetics, DRIFT-supported determination of sorption energy barriers and (de)sorption kinetics. The Ni/ZSM-5 (3.7 wt.% Ni, Si/Al = 28) emerged as the optimal choice for obtaining γ-valerolactone (GVL) as the desired product. Al-rich catalysts with high acid site amounts and low metallic Ni active site concentrations favored esterification, reducing hydrogenation activity, and impeding further hydrogenation of GVL to pentanoic/valeric acid (PA). To enhance PA formation, Ni/ZSM-5 (4 wt.% Ni, Si/Al = 750) with a high Si/Al ratio, was identified as crucial. The combination of described experiments and modelling is demonstrated beneficial for insightful investigation of the structure–activity relationship of Ni/ZSM-5 or any other mono/bi-functional catalysts. [ABSTRACT FROM AUTHOR]

Sludge pyrolysis has sparked the interest of researchers because of its capability to dispose of hazardous residues while producing valuable bioproducts. Numerous expensive and laborious experiments are conducted to understand sludge pyrolysis. Machine learning technology can eliminate the need for experimental measurements by systematically learning relationships between variables from historical data. This research aimed to propose a machine learning model to characterize sludge pyrolysis products. A comprehensive database covering various sludge types and pyrolysis reaction conditions was constructed from experimental data. The k-nearest neighbor algorithm was used to reconstruct the missing inputs of sludge composition. The principal component analysis method was then used to decrease dataset dimensionality and acquire relevant information. The obtained scores were normalized and introduced into three machine learning models. The input variables were the chemical properties of sludge and reaction conditions. The response parameters were the distribution and composition of pyrolysis products. Based on descriptive data analysis, the optimum bio-oil yield was obtained at temperatures between 500 and 600 °C. At higher temperatures (700–800 °C), a transition was observed in the product distribution towards more syngas. The random forest regression model showed the highest accuracy among the applied models, with a correlation coefficient higher than 0.813 and a relative mean squared error lower than 12.51. The SHAP analysis using the random forest algorithm was successfully conducted to understand the importance of input variables on output responses. The five top significant features affecting bio-oil yield were ash content, fixed carbon content, operating temperature, and volatile matter content. [Display omitted] • Machine learning technology was used to characterize wastewater sludge pyrolysis. • Random forest regression could predict the product distribution of sludge pyrolysis. • The best model estimated the process with a correlation coefficient higher than 0.813. • The importance of inputs on outputs was investigated by the random forest algorithm. • An easy-to-use software interface was developed for future research applications. [ABSTRACT FROM AUTHOR]

The determination of the catalyst's active phase helps improve the catalytic performance of the Fischer–Tropsch (FT) synthesis. Different phases of cobalt, including cobalt oxide, carbide, and metal, exist during the reaction. The content of each phase can affect the catalytic performance and product distribution. In this study, a series of cobalt carbide catalysts were synthesized by exposure of Co/Al2O3 catalyst to CH4 at different temperatures from 300 °C to 800 °C. The physicochemical properties of the carbide catalysts (CoCx/Al2O3) were evaluated by different characterization methods. The catalytic performances of the catalysts were investigated in an autoclave reactor to determine the role of cobalt carbides on the CO conversion and product distribution during the reaction. XRD and XPS analysis confirmed the presence of Co2C in the prepared catalysts. The higher carbidation temperature resulted in the decomposition of methane into hydrogen and carbon, and the presence of graphitic carbon was confirmed by XRD, XPS, SEM, and Raman analysis. The Co2C also decomposed to metallic cobalt and carbon, and the content of cobalt carbide decreased at higher carbidation temperatures. Higher content of Co2C resulted in a lower CO conversion and higher selectivity to light alkanes, mainly methane. The higher carbidation temperature resulted in the decomposition of Co2C to metallic cobalt with higher activity in the FT reaction. The CO conversion increased by increasing the carbidation temperature from 300 °C to 800 °C, due to the higher content of metallic cobalt. In the presence of pure hydrogen, the Co2C could be converted mainly into hexagonal, close-packed (hcp) Co with higher activity for dissociative adsorption of CO, which resulted in higher catalyst activity and selectivity to heavier hydrocarbons. [ABSTRACT FROM AUTHOR]

It is important to clarify the distribution of pyrolysis products from lignocellulosic biomass for its thermal transformation to produce high-quality bio-oil. Influences of the reaction temperature and catalysts on the pyrolysis product distribution from aspen wood (AW) and rice husk (RH) were studied by pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). The difference in components from the lignocellulosic biomass results in different pyrolysis characteristics of the biomass raw materials. The reaction temperature significantly influences the product distribution from AW and RH pyrolysis. In all AW catalysis experiments, acids (8.35%), ketones (3.79%), phenols (4.73%), and esters (1.50%) have the lowest content while carbohydrates (48.75%) demonstrate the highest content when taking zinc chloride (ZnCl2) as the catalyst; the HZSM-5 molecular sieve (HZSM-5) promotes the generation of esters (7.97%) and N-compounds (22.43%) while inhibiting production of aldehydes (2.41%); addition of an MCM-41 molecular sieve (MCM-41) is conducive to increasing the contents of aldehydes (21.29%), furans (5.88%), ketones (22.30%), acids (20.46%), and hydrocarbons (4.85%), while reducing the contents of alcohols (0) and carbohydrates (0). In all RH catalysis experiments, the addition of ZnCl2 helps increase the content of carbohydrates (39.16%) and decrease the contents of ketones (3.89%), phenols (5.20%), alcohols (2.34%), esters (1.13%), and N-compounds (3.09%); when applying HZSM-5 as the catalyst, hydrocarbons (18.28%) and alcohols (6.66%) reach their highest content while acids (13.21%) have the lowest content; MCM-41 promotes the generation of aldehydes (25.33%) and furans (5.55%) while inhibiting that of carbohydrates (1.42%).

Bimetallic Pt3Eu/C, Pt3La/C, and Pt3Ce/C electrocatalysts have been prepared, characterized, and tested for ethanol electro-oxidation (EEO). The materials were synthesized by chemical reduction with NaBH4, rendering nanosized particles with actual compositions close to the nominals and no alloy formation. X-ray photoelectron spectroscopy (XPS) confirmed that the auxiliary rare-earth metals were present on the surface in oxide form. The electrochemical analyses in acid and alkaline EEO evidenced that, compared to Pt/C, the addition of rare earth metals in the form of oxides reduced the onset potential, increased the current density, and enhanced the stability. The results were fully confirmed in the DEFC single-cell measurements. Finally, the presence of rare earth metals in the oxidized form increased the percentage of acetic acid as the final product, making the electrocatalysts more selective and efficient than Pt/C, where acetaldehyde was the main product.

The applications of alginate lyase are diverse, but efficient commercial enzymes are still unavailable. In this study, a novel alginate lyase with high activity was obtained from the marine bacteria Vibrio sp. Ni1. The ORF of the algB gene has 1824 bp, encoding 607 amino acids. Homology analysis shows that AlgB belongs to the PL7 family. There are two catalytic domains with the typical region of QIH found in AlgB. The purified recombinant enzyme of AlgB shows highest activity at 35 °C, pH 8.0, and 50 mmol/L Tris-HCl without any metal ions. Only K+ slightly enhances the activity, while Fe2+ and Cu2+ strongly inhibit the activity. The AlgB preferred polyM as substrate. The end products of enzymatic mixture are DP2 and DP3, without any metal ion to assist them. This enzyme has good industrial application prospects. [ABSTRACT FROM AUTHOR]

A novel star iminopyridyl ligand was synthesized in modest yield with 1.0 G star macromolecule and pyridine-2-carboxaldehyde as the raw materials. Reactions of the star iminopyridyl ligand with Fe(II), Co(II) and Ni(II) salts afforded metal complexes (Cat-Fe, Cat-Co and Cat-Ni) in good yields. The compounds were characterized by FT-IR, 1H NMR, 13C NMR, UV–Vis, ESI–MS and ICP-MS. In the presence of methylalumoxane (MAO), the iron, cobalt and nickel complexes have demonstrated higher ethylene oligomerization activity (up to 4.28 × 105 g/(mol Co h)), affording C4 as the major product as well as C6, C8 and C10-18 oligomers. The catalytic activity was quite sensitive to the kind of species. The nature of solvent and co-catalyst significantly affected both the catalytic activity and product distribution. Moreover, the effect of oligomerization parameters (reaction temperature, [Al]/[Co] molar ratio, ethylene pressure) on the catalytic activity and the product distribution was investigated. [ABSTRACT FROM AUTHOR]

[Display omitted] • High aromatics selectivity on ZnZrOx/ZSM-5 was observed by direct CO 2 hydrogenation. • Location and number of Brønsted acid sites were altered according to ZSM-5 morphology. • Nano-structured N-ZSM-5 was optimal for higher aromatics selectivity on hybrid catalyst. Direct synthesis of aromatics through CO 2 hydrogenation to oxygenates and its successive conversion to aromatics was investigated on hybridized ZnO-ZrO 2 metal oxides with ZSM-5. Hydrothermally synthesized micro-mesoporous ZSM-5 having four different morphologies with different Al distribution within ZSM-5 frameworks from small agglomerates to large elongated spherical particles such as nano (N-ZSM-5), hierarchically-structured hexagonal (H-ZSM-5), sheet-like (S-ZSM-5) and conventional cube-like (C-ZSM-5) structures. A larger number of strong Brønsted acid sites and small crystallite size of N-ZSM-5 in the hybridized ZnO-ZrO 2 /N-ZSM-5 were responsible for a largely enhanced CO 2 conversion of 22.9% and aromatics selectivity of 69.8% through methanol-to-aromatics reaction. The H-ZSM-5, having a larger number of external Brønsted acid sites, revealed a higher selectivity to alkylated tetramethyl benzene (TeMB) with 88.6% due to an enhanced surface C–C coupling reaction of aromatics formed from the tandem reaction. In addition, the selective distributions of Al species in the intersection micropores of sinusoidal and straight channels of the S-ZSM-5 showed an increased selectivity to xylene and trimethyl benzene (TriMB) and inhibited the formation of TeMB by further alkylation of surface intermediates through steric hinderance effects. The distributions of acidic sites and ZSM-5 morphology significantly altered local residence time resulted in different selectivity to aromatics and heavier hydrocarbons during gas-phase CO 2 conversion, which provided an efficient approach for direct CO 2 conversion to aromatics. [ABSTRACT FROM AUTHOR]

• Revealed the evolution of plastic waste in supercritical water/CO 2 gasification. • The addition of CO 2 in supercritical environment can promote the process of PVA depolymerization. • Temperature and reaction time apparently effect the gasification; • High pressure inhibits the production of hydrogen. Supercritical fluid gasification technology, as an environmentally friendly technology, can convert organic components of plastic waste into fuels and chemical materials. Moreover, the utilization of CO 2 as the gasification environment holds significant importance for reducing carbon emissions. To better comprehend the microscopic mechanism of plastic gasification in supercritical environment, this sthdy used the Reactive Force Field (ReaxFF) molecular dynamics method to study the gasification process of long-chain poly(vinyl alcohol) molecule in supercritical H 2 O/CO 2 under different reaction conditions. The result illustrated that during the gasification process, poly(vinyl alcohol) initially depolymerized into multiple long carbon chain (C 5 +) molecular fragments. Subsequently, these fragments underwent cleavage into short carbon chains and various gaseous small molecules. In this reaction, O radicals generated by CO 2 decomposition play a crucial role in promoting the cleavage of plastic C–C bonds. In addition, through the analysis of the products and chemical bonds, we found that increasing temperature and prolonging reaction time significantly enhance the gasification efficiency and hydrogen production of plastics. Conversely, exceedingly high pressure inhibits the gasification reaction. [ABSTRACT FROM AUTHOR]

In this work, a theoretical framework is developed to explain and predict changes in the product distribution of the propene dimerization reaction, which yields a mixture of C6 olefin isomers, resulting from the use of different porous materials as catalysts. The MOF-74 class of materials has shown promise in catalyzing the dimerization of propene with high selectivity for valuable linear olefin products. We show that experimentally observed changes in the product distribution can be explained in terms of the contribution of the pores to the free energy of formation, which are directly computed using molecular simulation. Our model is used to screen a library of 118 existing and hypothetical MOF and zeolite structures to study how product distribution can be tuned by changing pore size, shape, and composition of porous materials. Using these molecular descriptors, catalyst properties are identified that increase the selective reaction of linear olefin isomers, which are valued as industrial feedstocks. A pore size commensurate with the size of the desired linear products enhances linear conversion by sterically hindering the branched isomers. Another promising feature is the presence of open metal sites, which interact with the olefin π-bond to provide favorable binding sites for the linear isomers.

Carbon materials were formed by the hydrothermal carbonization of cellulose, which were used as support for carbon dioxide hydrogenation catalysts (Fe/C and Fe-Mn/C). In the presence of these catalytic systems, CO2 conversion reached 50%. It is shown that the manganese introduction into the Fe-containing catalytic system significantly affects the distribution of gaseous С1-С4 products and liquid С5+ hydrocarbons. Promotion leads to the suppression of methane formation and an increase in the proportion of C2-C4 light olefins in gaseous products, as well as to intensification of secondary processes with the formation of a significant amount of iso-structures in liquid products. The different distribution of С1-С6 alcohols in the oxygen-containing products on the Fe/C and Fe-Mn/C catalysts indicates the manganese effect on the routes of their formation.

Even though tremendous progress has been made on modified Fischer-Tropsch synthesis (FTS) multifunctional catalyst that composed of Fe-based component and acidic zeolite H-ZSM-5 for CO 2 hydrogenation into value-added chemicals, the structure-function relationship between the acidic zeolite H-ZSM-5 and product distribution is still under debate. Herein, a series of H-ZSM-5 zeolites with different Al locations and acidic properties are fabricated by varying the synthesis raw agents and conditions. After combining with the carbon-encapsulated Fe-based catalyst for alkenes synthesis from CO 2 hydrogenation, aromatics are directionally produced from the ellipsoidal H-ZSM-5 with Al species mainly located at the intersection of straight and sinusoidal channels, while the main products shift to iso-paraffins for the H-ZSM-5 with pillared nanosheet morphology owing to its Brønsted acid site-rich property. The Al location in H-ZSM-5 and the corresponding acidic property are systematically investigated, and the theoretical simulations illustrate that the Al species at the intersection channels could lower the energy barrier of key aromatization step. The Al richly located at straight/sinusoidal would boost the isomerization reaction. Our work not only clarifies the structure-function relationship of acidic zeolite H-ZSM-5 in valuable chemicals synthesis from CO 2 hydrogenation but also provides a novel protocol for controlled synthesis. [Display omitted] • H-ZSM-5 with different Al location and acidic property were prepared by various method. • Al location and acid property were investigated by experimental and theoretical calculation. • The structure-function relationship between H-ZSM-5 and product distribution was built. • Al at the channel intersection can boost aromatics synthesis, otherwise promote isomerization. [ABSTRACT FROM AUTHOR]

[Display omitted] • The terephthalate group in PBAT increased the final residuals (5.8%). • PM had a high amount of 2-propenoic acid due to the break of C-O bond. • Oxygen of PBS preferred to remain in the bio-oil, instead of bio-gas. • PCL had monomers in PM, indicating higher stabilization than the others. • The monomer of PCL was broken into bio-gas (21.76 %) at high temperatures (400–500 °C). Fast pyrolysis has emerged as a promising technology for converting fossil-based biodegradable plastics (FBBPs) into clean energy and high-value products with rapid volume reduction and efficient utilisation. The degradation mechanism during pyrolysis is crucial, and different chemical structures and reaction processes directly affect the treatment efficiency and economic benefits. In this study, three typical FBBPs, including poly(butylene adipate-co-terephthalate) (PBAT), polybutylene succinate (PBS) and poly(epsilon-caprolactone) (PCL), have been analyzed in rapid pyrolysis experiments and corresponding products. Being pyrolyzed at 550℃, three kinds of FBBPs exhibited distinctly different decomposition behaviors and characteristics. These differences can be attributed to the bond-breaking ways and pyrolysis mechanisms, which enhance the value of products. Specifically, PBS exhibited the highest abundance of bio-oils and particulate matter (total 90.58%) compared to PBAT and PCL, mainly converted to ketones and acids with a homogeneous component distribution, which was likely to help facilitate further utilisation. In addition, the oxygen of PBS remained in the bio-oil fraction while showing high levels of CO in the bio-gas. Moreover, PCL had the highest amount of bio-gas (21.76%) among the three FBBPs, indicating that it was more likely to break into small molecule products. Notably, the broken chains or macro-molecules of PCL were primarily converted into esters, with di(but-2-en-1-yl) adipate accounting for 57.5% of bio-oils. This work elucidated the transformation pathways and mechanism of FBBP pyrolysis, providing guidance for the treatment and resource utilisation of FBBPs. [ABSTRACT FROM AUTHOR]