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Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy 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.)

Objective The aim is to increase the aromatics content in the No.3 jet fuel produced by the diesel and wax oil mixed feed hydrocracking unit, so that it can meet the requirements of military No.3 jet fuel products. Methods The content of aromatics in No.3 jet fuel was increased by adjusting the following parameters: increasing the proportion of wax oil in the mixed raw material, increasing the oil density of the mixed raw material, reducing the temperature of the refining reactor bed, optimizing the temperature of the graded catalyst bed of the cracking reactor, and reducing the saturation depth of aromatics hydrogenation. Results Firstly, the aromatics content in jet fuel could be significantly increased by increasing the proportion of wax oil and the density of mixed raw material oil under constant treatment capacity. Secondly, under the condition of high diesel ratio raw material, by significantly reducing the temperature of the refining reactor bed, simultaneously reducing the bed temperature of the light oil catalyst, improving the bed temperature of the flexible and medium oil catalyst, the saturation depth of aromatics hydrogenation was reduced, the aromatics volume fraction in jet fuel products was greater than or equal to 8%, while ensuring the BMCI value of the tail oil was less than 13. Conclusions By increasing the wax oil proportion and mixed raw materials density to a specific value and reducing the bed temperature of the refined reactor and the saturation depth of aromatics hydrogenation, the target of aromatics volume fraction in jet fuel products greater than or equal to 8% can be achieved, which solves the problem of producing military No.3 jet fuel by diesel and wax oil mixed feed hydrocracking unit and has certain production guiding significance. [ABSTRACT FROM AUTHOR]

Faced with the situation of overcapacity in domestic refining capacity, it is imperative for refineries to transform towards chemical industry. Due to the highly periodicity of both the oil and chemical markets, refineries need to improve the production flexibility of clean oil and chemical feedstocks during the transformation process in order to maximize refinery revenue. Based on the typical overall process processing route of domestic refineries, a virtual refinery was designed. A flexible transformation scheme for the overall process with catalytic cracking as the core means was studied and designed for this virtual refinery: cracking gasoline was used to produce chemicals through a hydrogenation extraction unit, and cracking gasoline was used to produce clean oil through an S Zorb unit after appropriate treatment. Compared with the basic scheme, the total yield of gasoline and diesel in the catalytic cracking chemical production scheme decreased by 11. 20 percentage points, while the yield of olefins and aromatics increased by 5. 15 percentage points and 6. 39 percentage points, respectively, while the total crude oil processing volume remained unchanged. The total yield of gasoline and diesel in the catalytic cracking scheme for producing clean oil products decreased by 3. 55 percentage points, while the yield of olefins and aromatics increased by 4. 69 percentage points and 2. 15 percentage points, respectively. [ABSTRACT FROM AUTHOR]

This paper introduces the influence of heat treatment, microwave, oxidation and other chemical modification methods on the properties of activated carbon. The effects of pore structure, specific surface area and chemical properties of activated carbon on the adsorption of different aromatic hydrocarbons were summarized. It was found that the pore structure, specific surface area and surface chemical properties of activated carbon jointly affected the adsorption of monocyclic aromatic hydrocarbons; the pore structure and specific surface area affect the adsorption of PAHs more than the surface chemical properties. [ABSTRACT FROM AUTHOR]

By comparing the separation effects and applicability of Ag+-thin layer chromatography (Ag+-TLC) and column chromatography on aromatic hydrocarbons with different ring numbers in crude oil, this article aims to provide theoretical support for the quantitative analysis of aromatics and isotope analysis of monomer hydrocarbon in organic geochemical research. The results showed that Ag+-TLC can better enrich monocyclic aromatics and differentiate the monocyclic aromatics of different isomers into different components, but has a poor effect in enriching palycyclic aromatics, which may lead to severe losses and possible peak interference. Column chromatography has better separation effects on dinuclear and polycyclic aromatic compounds. Therefore, Ag+-TLC, suitable for the fine separation of monocyclic aromatics, can be used to enrich alkylbenzenes and aryl isoprenoids, and meets the detection requirements for measuring their monomer hydrocarbon isotopes; while column chromatography can effectively enrich series of compounds such as naphthalene, phenanthrene, and triaromatic steroids, and meets the requirements for detecting the separating degree of monomeric hydrocarbon isotopes.

The conversion of coal-based methanol to benzene, toluene, and xylene is an important technology to promote the efficient and clean conversion of coal. However, the control of reaction process on a single catalyst is difficult and the aromatic selectivity is low. Coated ZSM-5 was prepared by steam-assisted crystallization, in which ZSM-5 with a Si/Al ratio of about 50 was mixed into dry gel with a Si/Al ratio of 220. Under the catalysis of the coated ZSM-5, the two-step reaction of methanol to olefin and olefin aromatization was performed to improve the aromatic selectivity. The effect of coating ratio on the catalytic performance of the prepared ZSM-5 was investigated. The results show that when the coating ratio was less than 0.5, the silicon and aluminum species in the gel could be coated on the surface of parent ZSM-5. The coating structure with high Si/Al ratio promoted the conversion of methanol to light olefin, and further enhanced the stepwise aromatization process of methanol. The aromatic selectivity increased from 12.9% of the original powder to 14.5% and the selectivity of light aromatic in total aromatic products also increased from 61.8% to 66.5%. When the coating ratio increased to 2, some silicon and aluminum species nucleated independently outside the original powder to form small crystal. Although the total aromatic selectivity increased to 15.2%, the small crystal promoted the alkylation of light aromatic to form heavy aromatic hydrocarbons, while the light aromatic selectivity decreased.

Objective The reaction rules of different hydrocarbon in deep catalytic cracking（DCC） process was studied to improve hydrocarbon utilization rate and selectivity of target products, and explore the potential of “oil to chemicals”. Methods Based on the hydrocarbon compositions of raw oil and products in DCC, the apparent conversion rate of different hydrocarbons from raw oil to products were analyzed in detail, and the conversion and formation pathways of different hydrocarbons were analyzed and discussed. Results During the catalytic cracking reaction, the apparent conversion rates of paraffin hydrocarbons, cycle-hydrocarbons and aromatics were 93.06%, 97.05% and 58.53%, respectively. In the aromatics, the apparent conversion rates of single ring, double ring, third ring, four ring and five rings and above were 61.49%, 11.34%, 65.17%, 29.27% and 96.35%, respectively. The molar ratio of catalytic cracking products to raw oil was 7.68, and the molar ratio of product aromatics to raw oil aromatics was 2.99. Hydrocarbons with mass fraction of 27.50% in the liquid product could be further converted into the target product, and the proportion of monocyclic aromatic hydrocarbons in the product generated by aromatization reaction from the non-aromatics in the feed oil was 96.16%. Conclusions The catalytic cracking conversions of alkanes and cycloalkanes were relatively complete, while the apparent conversion rate of aromatics was relatively low, and the apparent conversions of aromatics with different ring numbers were quite different, showing the characteristics of high apparent conversion rate of aromatic hydrocarbons with odd ring numbers and low apparent conversion rate of aromatic hydrocarbons with even ring numbers. The catalytic cracking reaction and aromatization reaction were the most important reactions of the DCC process. The apparent lightening order of different hydrocarbons was alkanes ＞ monocyclic aromatic hydrocarbons ＞ cycloalkanes ＞ bicyclic aromatic hydrocarbons ＞ tricyclic and above aromatic hydrocarbons. The monocyclic aromatic hydrocarbons in the products mainly came from the aromatization reaction of non-aromatic hydrocarbons in the raw oil. Hydrocarbons that can be converted into target products in liquid products could be further reduced. [ABSTRACT FROM AUTHOR]

Lignin is a complex three-dimensional amorphous natural aromatic polymer with great potential to be converted into biofuels as an alternative to traditional fossil fuels. Pyrolysis technology has been proven to be as an effective pathway for converting lignin into high-value chemicals. However, there are challenges such as low product selectivity and poor product stability in the direct pyrolysis process, which limit the efficient conversion and economic viability of lignin-based conversion. Currently, catalytic fast pyrolysis technology is regarded as a useful technology in overcoming these challenges. This paper extensively elaborates on the intricate structure of lignin by introducing its basic structural units and the multitude of linkage patterns it encompasses. Furthermore, it reviews the primary sources and diverse classifications of lignin. Subsequently, based on the pyrolysis characteristics of lignin, the key stages of its pyrolysis process, including the initial, primary, and carbonization stages, are extensively discussed. Due to the unsatisfactory quality of the direct pyrolysis products, this paper also explores the necessity of catalytic fast pyrolysis and provides a comprehensive introduction and overview of commonly used catalysts. Finally, the paper proposes the future development directions of lignin catalytic fast pyrolysis in terms of depolymerization and value addition.

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 Chemistry & Industry of Forest Products is the property of Chemistry & Industry of Forest Products 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.)

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 Surfactant Detergent & Cosmetics (1001-1803) is the property of China Surfactant Detergent & Cosmetics 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.)

木质素;解聚;Ni基催化剂;均相催化剂;芳香化合物The depolymerization of lignin over different acid/base homogeneous catalysts and Ni/C was studied.The effects of Lewis acid and base on the influence of lignin conversion and aromatics yield were investigated.The result showed that the yield of aromatics from lignin was higher when NaOH and Ni/MLG（nickel/multilayer graphite） as catalysts than others.Moreover, the yield of phenols and guaiacols increased when Lewis acid and Ni/MLG as catalysts.And the yield of phenyl alcohols and arenes increased when alkali and Ni/MLG as catalysts.This article will provide a reference for the research of high-value utilization of lignin. [ABSTRACT FROM AUTHOR]

K modified HY molecular sieves were prepared and their catalytic performance in the benzylation of aromatic hydrocarbons and benzyl alcohol to diphenylmethane were studied・ A series of HY molecular sieves KHY1 0, KHY2 0 ?KHY3 0 ?KHY4 0 and KHY5 0 with different K loaded were prepared by the equal volume impregnation and applied to catalyze the benzylation of aromatic hydrocarbons and benzyl alcohol for synthesis of diphenylmethane・ The modified molecular sieves were characterized by XRD, SEM, EDS, Py-IR and N2 adsorption/desorption analysis・ The aromatic hydrocarbons and benzyl alcohol were catalyzed by KHYT for 4 h at 373 K, and the progress of the reaction was monitored by gas chromatography. The result showed that K is evenly distributed on the surface of the molecular sieve as an active component, and the introduction of potassium ion will not destroy the structure of the HY molecular sieve・ KHY2 0 is the best catalyst for catalyzing the benzylation of aromatic hydrocarbons, and has excellent regeneration performance・ After 5 times of reuse, the catalytic efficiency had almost no influence. [ABSTRACT FROM AUTHOR]

Copyright of Plastics Science & Technology / Suliao Ke-Ji is the property of Plastics Science & Technology 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.)

A total of 99 volatile organic compounds (VOCs) are measured using online Gas Chroma Mass Spectrometer/Flame lonization Detector (GC-MS/FID) at a nural site in Dezhou from November 2017 Jutary, 2018. The VOCS composition, diumal variation, sources, one formation potential (OFP) and o a ganic aerosot (SOA) yields were analyzed. The average volume fraction of total VOC was (47. 74-33. II) x10-9 and alkanes were the most abundant VOCs species (40. 66%).The diurnal variation of VOC. bod high ener- tration in morning and evening but low concentration at noon. Propane, propylene, butane, sleep,and dichloromethane were mainly from liquid petrol as usage, biogenie soumes, vehicle, and Back trajectory model analysis showed that air mass from the north might contribute to VOC concentrate The OFP of alkanes, alkenes, and aromatics were (34, 8733. 60) .(120. 4811 S. 76) and (59.77:94 14) ug/ m³ spectively and ethylene.propylene tourne and m/p-sylene were the top 4pecies which WP The SOA formation was explored and aromatics, including toluene, m/plene, and beee,contributed me SOA (93. 7).As a result, reducing animatics emission will be an apicunt way to the and PM pallation in Dezhou. [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.)

Aromatics are important platform chemicals in the petrochemical industry, and are produced primarily on the catalytic reforming of petroleum resources. With the declining resources of crude oil, increasing global environmental concerns and the growing demand for aromatics, the traditional aromatics production technology is facing severe challenges. In recent years, catalytic fast pyrolysis ( CFP)of biomass to produce aromatics attracts great attentions owing to its green and sustainable characteristics. Microporous zeolite is known as the best catalyst in CFP process due to its high surface area, strong acidity, shape- selectivity and superior hydrothermal stability. However, the low mass- transfer rates and high yield of coke during CFP results in the short lifetime of catalysts. The introduction of mesopores in microporous zeolite to form the hierarchical zeolite can not only improve the mass transfer but also keep the strong acidity and shape- selectivity to improve the catalytic activity and decrease coke deposition. We review the biomass feedstock and reaction chemistry in the CFP of biomass, and mainly reviews the advantages of hierarchical zeolite as well as its application and innovation. Finally, the challenges and perspectives of catalytic fast pyrolysis technique are summarized. [ABSTRACT FROM AUTHOR]

To investigate the characteristics and sources of atmospheric volatile organic compounds (VOCs) in a typical industrial zone in Dongguan, 56 VOCs species were continuously measured in Houjie Town of Dongguan in summer of 2020. In addition, mass concentrations of O 3 , NO x , and CO and meteorological data were synchronously collected. Then, characteristics of total VOCs and major species, the contributions of major VOCs species to ozone formation potential (OFP), and source apportionment of VOCs under the different ozone concentrations were discussed. The mean mixing ratio of VOCs was 53.1×10 -9 including aromatics (24.7×10 -9 ), alkanes (23.7×10 -9 ), alkenes (3.9×10 -9 ), and alkynes (0.7×10 -9 ). The mean mixing ratios of aromatics, alkanes, alkenes, and alkynes increased approximately 10%, 43%, 38%, and 98% during the period of ozone pollution, respectively, compared with those during the period of non-ozone pollution. Aromatics contributed the most to OFP during the periods of both ozone pollution and non-ozone pollution, followed by alkanes, alkenes, and alkynes. Solvent sources, liquefied petroleum gas (LPG) leakage, fossil fuel combustion, and hydrocarbon volatilization were resolved using the PMF model, which accounted for 60%±20%, 16%±11%, 15%±11%, and 9%±6% of total VOCs, respectively. During the period of ozone pollution, the contribution of solvent sources to the total VOCs decreased to 44%, whereas that of LPG leakage and hydrocarbon volatilization increased to 21% and 16%, respectively.

As coking precursors, aromatic hydrocarbons have an effect on the cracking stability of fuels. A method for identifying and quantitating aromatics in the supercritical cracking products of jet fuel was established by comprehensive two-dimensional gas chromatography coupled with mass spectrometry (GC×GC-MS). The effects of main chromatographic conditions such as initial oven temperature and modulation period on the separation of supercritical cracking products were studied. The method has good separation ability for polycyclic aromatic hydrocarbons (PAH) isomers. A total of 27 aromatics, including monocyclic aromatic hydrocarbons, bicyclic aromatic hydrocarbons, tricyclic aromatic hydrocarbons, tetracyclic aromatic hydrocarbons, etc., were identified based on standard mass spectra, the retention times of standards and literature reports. Moreover, the corresponding quantitative determination was achieved by external standard method of GC×GC-FID. The results showed that the contents of aromatics increased with the increase of gas yield. When gas yield reached 22%, the bicyclic aromatic hydrocarbons began to produce, and their contents increased exponentially with the increase of gas yield. Compared with the traditional GC-MS, the method has better separation and qualitative ability, and can be applied to the separation of complex samples and qualitative and quantitative analyses of cracking products.