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含油污泥 1

烃降解产甲烷 1

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Insights into carbon-based materials for catalytic dehydrogenation of low-carbon alkanes and ethylbenzene

《化学科学与工程前沿（英文）》 2023年第17卷第11期页码 1623-1648 doi: 10.1007/s11705-023-2328-6

摘要： Direct dehydrogenation with high selectivity and oxidative dehydrogenation with low thermal limit has been regarded as promising methods to solve the increasing demands of light olefins and styrene. Metal-based catalysts have shown remarkable performance for these reactions, such as Pt, CrO_x, Co, ZrO_x, Zn and V. Compared with metal-based catalysts, carbon materials with stable structure, rich pore texture and large surface area, are ideal platforms as the catalysts and the supports for dehydrogenation reactions. In this review, carbon materials applied in direct dehydrogenation and oxidative dehydrogenation reactions including ordered mesoporous carbon, carbon nanodiamond, carbon nanotubes, graphene and activated carbon, are summarized. A general introduction to the dehydrogenation mechanism and active sites of carbon catalysts is briefly presented to provide a deep understanding of the carbon-based materials used in dehydrogenation reactions. The unique structure of each carbon material is presented, and the diversified synthesis methods of carbon catalysts are clarified. The approaches for promoting the catalytic activity of carbon catalysts are elaborated with respect to preparation method optimization, suitable structure design and heteroatom doping. The regeneration mechanism of carbon-based catalysts is discussed for providing guidance on catalytic performance enhancement. In addition, carbon materials as the support of metal-based catalysts contribute to exploiting the excellent catalytic performance of catalysts due to superior structural characteristics. In the end, the challenges in current research and strategies for future improvements are proposed.

关键词： carbon materials dehydrogenation active sites mechanism catalytic performance support

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Prediction of the flash points of alkanes by group bond contribution method using artificial neural networks

PAN Yong, JIANG Juncheng, WANG Zhirong

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 390-394 doi: 10.1007/s11705-007-0071-z

摘要： A group bond contribution model using artificial neural networks, which had the high ability of nonlinear of prediction, was established to predict the flash points of alkanes. This model contained not only the information of group property but also connectivity in molecules. A set of 16 group bonds were used as input parameters of neural networks to study the correlation of molecular structures with flash points of 44 alkanes. The results showed that the predicted flash points were in good agreement with the experimental data that the absolute mean absolute error was 6.9 K and the absolute mean relative error was 2.29%, which were superior to those of traditional group contribution methods. The method can be used not only to reveal the quantitative correlation between flash points and molecular structures of alkanes but also to predict the flash points of organic compounds for chemical engineering.

关键词： information nonlinear quantitative correlation superior molecular

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Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie

《化学科学与工程前沿（英文）》 2018年第12卷第2期页码 226-238 doi: 10.1007/s11705-018-1709-8

摘要： The methanol-to-olefin (MTO) reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 (65 weight percentage, wt-%) embedded in an amorphous SiO matrix (35 wt-%). The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form (E-SAPO-34) were analyzed and results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 °C, using an aqueous methanol mixture (80 wt-% water content) fed at a weight hour space velocity (WHSV) of 1.21 h . At 300 °C, a low conversion was observed combined with catalyst deactivation, which was ascribed to oligomerization and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450 °C, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450 °C, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.

关键词： MTO SAPO-34 temperature extrusion coke light alkanes

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长期培养和宏组学分析揭示了烃污染环境中的甲基营养型产甲烷途径 Article

刘一凡, 陈静, 刘忠林, 侯兆伟, 梁波, 王立影, 周蕾, 寿利斌, 林丹丹, 杨世忠, 刘金峰, 伍晓林, 顾继东, 牟伯中

《工程（英文）》 2023年第24卷第5期页码 265-276 doi: 10.1016/j.eng.2021.08.027

摘要：

针对石油烃污染的厌氧环境, 利用微生物的代谢作用将石油烃转化为甲烷是一种潜在的生物修复策略。然而, 目前对于微生物厌氧烃降解产甲烷的机制尚不清楚。经过十年的持续富集和转接培养, 我们获得了一种能够降解正构烷烃 (C₁₅~C₂₀) 并且产甲烷富集培养体系, 并且经过转接培养该培养物在甲烷生产的动力学特性方面得到了持续的提高。综合宏基因组和宏转录组的分析结果, 发现正构烷烃主要通过Desulfosarcinaceae、Firmicutes和Synergistetes菌通过富马酸加成的方式进行起始活化, 然后在Tepidiphilus菌的协同作用下进一步降解。同时, 体系中含量较多的Anaerolineaceae菌主要负责死细胞生物质的回收。根据宏转录组学分析结果, 甲烷主要通过H₂依赖型的甲基营养甲烷途径产生, 主要由候选门Verstraetearchaeta内的Methanomethyliaceae通过利用死细胞生物质回收代谢过程中产生的三甲胺来产生甲烷。这些发现表明, 依赖H2的甲基营养产甲烷菌以及甲基营养产甲烷菌可能在含石油烃的地下生态系统的碳循环过程中发挥着重要的作用。

关键词：烃降解产甲烷含油污泥生物修复烷烃