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Emerging trends in the selective production of value-added aromatics

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Science China Chemistry 2025年第1期68卷 15-20页

作者： Yuchao Wu Houliang Dai Weisheng Yang Yaxing Li Lichen Liu Petrochemical Research Institute company Limited China National Petroleum Corporation Engineering Research Center of Advanced Rare Earth Materials Department of Chemistry Tsinghua University

1 Introduction Aromatics (mainly benzene, toluene, and xylenes, BTX) are essential intermediates in the chemical industry. They are employed in the synthesis of a broad spectrum of chemicals and materials, e.g., various polymers, plastics, resins, solvents, dyes, pharmaceuticals [1]. The manufacturing pathway of BTX mainly includes petroleum reforming of naphtha, coal-to-aromatics, methanol-to-aromatics [2].

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ADVANCES IN LIQUID CRYSTALLINE POLYESTERS

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Chinese Journal of Polymer Science 1992年第3期10卷 195-202页

作者： W. J. Jackson Jr. Research Laboratories Eastman Chemical Company Eastman Kodak Company Kingsport Tennessee U.S.A.Research Laboratories Eastman Chemical Company Eastman Kodak Company Kingsport Tennessee U.S.A.

Advances have been made in understanding the interactions of composition, molecular weight, liquid crystallinity,orientation, and three-dimensional crystallinity on the properties of injection-molded and melt-spun liquid crystalline polyesters (LCP's). Two classes of potentially low-cost LCP's were compared:(1) semiflexible LCP's prepared from 1,6-hexanediol and the dimethyl ester of either trans-4, 4'stilbenedicarboxylic acid or 4.4 ' biphenyldicarboxylic acid and (2) all-aromatic LCP's prepared from terephthalic acid, 2, 6-naphthalenedicarboxylic acid, the diacetate of hydroquinone, and the acetate of p-hydroxybenzoic acid. The effects of composition on the plastic properties of the 4-component all-aromatic LCP's were determined with the aid of a 3 x 3 factorial statistically designed experiment, the generation of equations with a computer program, and the plotting of three-dimensional figures and contour diagrams. The effects of absolute molecular weight (M_w) on the tensile strengths of the semiflexible LCP's and one of the all-aromatic LCP's having an excellent balance of plastic properties were also compared, and it was observed that the semiflexible LCP's required M_w's about 4 times higher than the all-aromatic LCP to attain a given strength. Persistence lengths and molecular modeling were used to explain these differences.

关键词： Liquid crystal thermotropic polyester plastic properties

Kinetics of oxidative coupling of methane:Bridging the gap between comprehension and description

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Journal of Natural Gas Chemistry 2009年第3期18卷 273-287页

作者： Mikhail Sinev Zukhra Fattakhova Vladimir Lomonosov Yurii Gordienko Semenov Institute of chemical Physics ZAO "SCHAG" company

The development of notions about the mechanism of the oxidative coupling of methane （OCM） over oxide catalysts and corresponding progress in its kinetic description are reviewed and discussed. The latter becomes essential at the stage of scaling up and optimization of the process in pilot and industrial reactors. It is demonstrated that the main achievements in the development of kinetic models can be reached by combining the approaches conventionally used in homogeneous gas-phase kinetics and in heterogeneous catalysis. In particular, some important features of the OCM process can be described if several elementary reactions of free radical species （formation and transformation） with surface active sites are included into the detailed scheme of methane oxidation in gas. However, some important features, such as a non-additive character of the reciprocal influence of methane and ethane in the case of their simultaneous presence in the reaction mixture, cannot yet be described and comprehended in the framework of schemes developed so far. Possible ways towards an advanced kinetic model, accounting the main principles of catalyst functioning （redox nature of active sites） and pathways of product formation （via free radicals） are traced.

关键词： natural gas methane oxidative coupling of methane ethane ethylene kinetics mechanism rate equations

Poly(styrene-co-divinylbenzene)-PAMAM-IDA chelating resin: Synthesis, characterization and application for Ni(II) removal in aqueous

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Journal of Central South University 2014年第9期21卷 3479-3484页

作者：刘耀驰李学农王春志孔秀周荔子 College of Chemistry and chemical Engineering Central South University Baling company China Petroleum & Chemical Corporation

PS-PAMAM-IDA chelating resins were prepared by low-generations of polyamidoamine(PAMAM) and then chloroacetic acid functionalizing commercially available ammoniated polystyrene matrix, to preconcentrate Ni2+ from synthetic aqueous samples. Different generations of PAMAM were used to obtain different chelating resins, PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA. The synthesized resins were characterized by FTIR and elemental analysis. The effect of solution pH, kinetic studies, resin loading capacity, matrix effects etc., on metal ion adsorption to adsorbent phase, were studied by batch method. The PS-1.0G PAMAM-IDA resin was the most excellent adsorbents, with a maximum adsorption capacity of(24.09±1.79) mg/g for Ni2+ ion at pH=7. The interpretation of the equilibrium data was given by Langmuir isotherms model, and the correlation coefficient values for PS-IDA, PS-1.0G PAMAM-IDA and PS-2.0G PAMAM-IDA resins were 0.992, 0.994 and 0.987, respectively.

关键词： chelating resin polyamidoamine iminodiacetic acid properties Ni(II)

Analysis of Causes Leading to High Bromine Number of C_8^+ Aromatics and Short Clay Service Life and Countermeasures Proposed

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China Petroleum Processing & Petrochemical Technology 2007年第2期9卷 23-28页

作者： Li Yousong Ni Xiaoliang Yah Jun SINOPEC Zhenhai Refining and chemical Branch company Ningbo 315207

After comparing the operating status of other catalytic reforming units and evaluation of the side-cut stream tests, the refinery investigated the influence of the feedstock property, clay types, and operating regime of the clay tower and catalytic reforming unit on the service life of the clay. Test results had revealed that the low potential aromatic content of the reformer feed and high operating severity were the critical causes leading to high bromine number of the C8^＋ aromatics feed for the PX unit and the shortened service life of clay. This article also puts forward the corresponding remedial measures.

关键词： C8^+ aromatic feedstock bromine number clay catalytic reforming unit

Elucidating the effect of oxides on the zeolite catalyzed alkylation of benzene with 1-dodecene

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Chinese Journal of chemical Engineering 2023年第4期56卷 126-135页

作者： Shiyong Xing Yan Cui Tiefeng Wang Jinwei He Minghan Han Beijing Key Laboratory of Green chemical Reaction Engineering and Technology Department of Chemical EngineeringTsinghua UniversityBeijing 100084China Petrochemical Research Institute PetroChina Company LimitedBeijing 100195China Henan Energy and chemical Industry Group company Limited Zhengzhou 450046China

In the present work, the effect of oxides on the alkylation of benzene with 1-dodecene was comprehensively investigated over MCM-49 n-heptanol, n-heptaldehyde and n-heptanoic acid were selected as the model oxides herein, and obvious decrease of lifetime could be caused by only trace amount of oxides added in the feedstocks. However, the deactivated catalysts were difficult to be regenerated by extraction with hot benzene. Additionally, coke-burning was also proved to be incapable to regenerate the deactivated catalysts mainly for the dealumination during calcination. Further characterizations complementary with DFT calculations were conducted to demonstrate that the deactivation was mainly due to the firm adsorption of oxides on the acid sites.

关键词： Zeolite 1-dodecene Alkylation Oxides Deactivation

Some recent advances in fluidized-bed polymerization technology

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Particuology 2010年第6期8卷 578-581页

作者： Jan van Egmond Mike Tilston Union Carbide Corporation a subsidiary of The Dow Chemical CompanyFreeportTX 77541USA

The fluidized-bed polymerization process has been in use for decades. From the manufacturer＇s perspective it is desirable to improve technology without major modification of the reactor system. Therefore, in order to meet the demand for new products or more efficient reactor operation, manufacturers prefer to improve the catalyst system in the most cost effective manner. Using polypropylene production as an example, some recent advances in fluidized-bed polymerization technology are presented.

关键词： Fluidized bed Polymerization Polypropylene Catalyst Donor Kinetics

The formation and temperature stability of microemulsion emulsified by polyoxyethylene ether surfactant

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Progress in Natural Science:Materials International 2023年第3期33卷 295-300页

作者： Haixia Zhang Jiahui Xia Chenguang Ding Bin Xu Shoulong Wang Zongxu Wu Weimin Zhao Department of chemical Engineering and Safety Binzhou University School of Chemistry and chemical Engineering Yangzhou University Binzhou Dayou New Energy Development company Limited

The effect of polyoxyethylene chain length on the formation and temperature stability of W/O microemulsion emulsified by polyoxyethylene ether surfactant is investigated by dissipative particle dynamics simulation(DPD)on the mesoscopic level. The results show that W/O microemulsions can be formed by three polyoxyethylene chain length ether nonionic surfactants with decreasing the water-oil ratio equal to increasing the oil phase content. However, W/O microemulsion is most easily formed by diethylene glycol monododecyl ether(H1T2)with the smallest oxyethylene *** results of temperature stability show that W/O microemulsion emulsified by H1T2 has better stability resistant to high or low temperature. In addition, the interfacial tension of the W/O microemulsion system is the lowest, the end-to-end distance of the surfactant molecule is smallest, and the molecular chain is the most curved at the water-oil interface. The theoretical simulation results can guide the formation of the W/O microemulsion induced by polyoxyethylene ether nonionic surfactant, and provide the guidance for its practical application.

关键词： End-to-end distance DPD W/O microemulsion Mean interfacial tension

Study on Structure and Crystallinity of A New Biodegradable Aliphatic-Aromatic Copolyester

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China Petroleum Processing & Petrochemical Technology 2011年第4期13卷 64-69页

作者： Wang Xiaohui Shi Jun Chen Ying Fu Zhifeng Shi Yan State Key Laboratory of chemical Resource Engineering Beijing University of Chemical Technology Beo＇ing 100029 Liaoyang Petrochemical company PetroChina Company Limited Liaoyang 111003

A series of biodegradable aliphatic-aromatic copolyesters, poly(butylene terephthalate-co-butylene adipate-co- ethylene terephthalate-co-ethylene adipate) (PBATE), were synthesized from terephthalic acid (PTA), adipic acid (AA), 1,4-butanediol (BG) and ethylene glycol (EG) through direct esterification and polycondensation. The sequence structure and crystallinity of the copolyester were investigated by 1H NMR spectroscopy and the wide-angle X-ray diffractometry (WAXD). The analytical results showed that the PBATE copolyester was a random copolymer and the composition of PBATE copolyester was almost consistent with the feed molar ratios. The crystal structure of PBATE copolyester belonged to the triclinic crystalline system; The variation in melting point of the synthesized PBATE copolyester agreed well with the estimation obtained by the Flory equation and was applicable to the random copolymer.

关键词： biodegradable polyester sequence structure crystallinity aliphatic aromatic