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二甲苯 1

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Progress in the research and development of p-xylene liquid phase oxidation process

WANG Lijun, CHENG Youwei, WANG Qinbo, LI Xi

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 317-326 doi: 10.1007/s11705-007-0058-9

摘要： The process of -xylene liquid phase oxidation to produce purified terephthalic acid (PTA) involves a series of liquid phase radical reactions, chemical absorption, reactive crystallization, and evaporation. A commercial PTA production flow sheet includes a number of unit operations, which construct a complex process system. In this paper, a review of research and development (R&D) works on PTA process carried out in Zhejiang University during recent years is introduced. The works cover the oxidation and crystallization kinetics, gas-liquid mass transfer and evaporation, reactor modeling, database development, novel reactor design, process modeling, simulation, and optimization. The author emphasizes the viewpoint through this case study that chemical reaction engineering should be developed to process system engineering to extend its scope, and particular attention should be paid on reactor and process modeling.

关键词： development -xylene Zhejiang University particular attention viewpoint

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Adsorption of toluene, ethylbenzene and xylene isomers on multi-walled carbon nanotubes oxidized by different

Fei YU, Jie MA, Yanqing WU

《环境科学与工程前沿（英文）》 2012年第6卷第3期页码 320-329 doi: 10.1007/s11783-011-0340-4

摘要： Multi-walled carbon nanotubes (MWCNTs) were fabricated and oxidized by different concentrations of sodium hypochlorite (NaOCl) solutions. The untreated MWCNTs and modified MWCNTs were employed as adsorbents to study their characterizations and adsorption performance of toluene, ethylbenzene and xylene isomers (TEX) in an aqueous solution. The physicochemical properties of MWCNTs were greatly affected after oxidation, which influences TEX adsorption capacity. The 3% NaOCl-oxidized MWCNTs shows the greatest enhancement in TEX adsorption, followed by the 30% NaOCl. More interestingly, the 15% NaOCl-oxidized MWCNTs has lower adsorption capacities than untreated MWCNTs. The adsorption mechanism of TEX on treated MWCNTs is attributed to the combined action of hydrophobic interaction, π-π bonding interaction between the aromatic ring of TEX and the oxygen-containing functional groups of MWCNTs and electrostatic interaction. 3% NaOCl solution could not only introduce much oxygen-containing functional groups on MWCNTs, but also lead to less damage for the pore structure. This suggests that the CNTs-3% NaOCl is efficient adsorbent for TEX and that they may possess good potential for TEX removal in wastewater treatment.

关键词： adsorption toluene ethylbenzene and xylene isomers (TEX) multi-walled carbon nanotube surface oxidation

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C₈芳烃异构化催化剂的开发及应用

乔映宾

《中国工程科学》 1999年第1卷第1期页码 73-77

摘要：

文章介绍了SKI系列C₈芳烃异构化催化剂研究工作的进展。阐述了催化剂研制开发的创新思路以及该催化剂的优异性能。该催化剂采用丝光沸石固体酸取代常规的卤素酸，因此操作过程中既可省去补氯和碱洗等繁杂过程，又可避免设备腐蚀并改善了操作环境，是一种环境友好的催化剂。该催化剂可使贫对二甲苯或贫对、邻二甲苯的混合C₈芳烃异构为接近热力学平衡的C₈芳烃，C₈芳烃的选择性大于97%，使用寿命可达5年以上。并介绍了该催化剂在引进的七套C₈芳烃异构化工业装置上取代了进口催化剂，将该科技成果转化为现实的生产力所取得的成绩。

关键词：异构化催化剂二甲苯

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Synthesis, physicochemical characterizations and catalytic performance of Pd/carbon-zeolite and Pd/carbon-CeO

Zeinab JAMALZADEH, Mohammad HAGHIGHI, Nazli ASGARI

《环境科学与工程前沿（英文）》 2013年第7卷第3期页码 365-381 doi: 10.1007/s11783-013-0520-5

摘要： In this work, xylene removal from waste gas streams was investigated via catalytic oxidation over Pd/carbon-zeolite and Pd/carbon-CeO nanocatalysts. Activated carbon was obtained from pine cone chemically activated using ZnCl and modified by H PO . Natural zeolite of clinoptilolite was modified by acid treatment with HCl, while nano-ceria was synthesized via redox method. Mixed supports of carbon-zeolite and carbon-ceria were prepared and palladium was dispersed over them via impregnation method. The prepared samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller surface area (BET), Fourier transform infrared spectroscopy (FTIR) and thermogravimetric (TG) techniques. Characterization of nanocatalysts revealed a good morphology with an average particle size in a nano range, and confirmed the formation of nano-ceria with an average crystallite size below 60 nm. BET analysis indicated a considerable surface area for catalysts (~1000 m ·g ). FTIR patterns demonstrated that the surface groups of synthesized catalysts are in good agreement with the patterns of materials applied in catalyst synthesis. The performance of catalysts was assessed in a low-pressure catalytic oxidation pilot in the temperature range of 100°C–250°C. According to the reaction data, the synthesized catalysts have been shown to be so advantageous in the removal of volatile organic compounds (VOCs), representing high catalytic performance of 98% for the abatement of xylene at 250°C. Furthermore, a reaction network is proposed for catalytic oxidation of xylene over nanocatalysts.

关键词： Pd/carbon-CeO₂ Pd/carbon-zeolite pine cone ZnCl₂ catalytic oxidation xylene