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Effect of Al_2O_3 Binder on the Precipitated iron-based catalysts for Fischer-Tropsch Synthesis

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Journal of Natural Gas Chemistry 2007年第2期16卷 130-138页

作者： Hai-Jun Wan Bao-Shan Wu Xia An Ting-Zhen Li Zhi-Chao Tao Hong-Wei Xiang Yong-Wang Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China Graduate University of Chinese Academy of Sciences Beijing 100039 China

A series of iron-based Fischer-Tropsch synthesis （FTS） catalysts incorporated with Al2O3 binder were prepared by the combination of co-precipitation and spray drying technology. The catalyst samples were characterized by using N2 physical adsorption, temperature-programmed reduction/desorption （TPR/TPD） and MSssbauer effect spectroscopy （MES） methods. The characterization results indicated that the BET surface area increases with increasing Al2O3 content and passes through a maximum at the Al2O3/Fe ratio of 10/100 （weight basis）. After the point, it decreases with further increase in Al2O3 content. The incorporation of Al2O3 binder was found to weaken the surface basicity and suppress the reduction and carburization of iron-based catalysts probably due to the strong K-Al2O3 and Fe-Al2O3 interactions. Furthermore, the H2 adsorption ability of the catalysts is enhanced with increasing Al2O3 content. The FTS performances of the catalysts were tested in a slurry-phase continuously stirred tank reactor （CSTR） under the reaction conditions of 260 ℃, 1.5 MPa, 1000 h^-1 and molar ratio of H2/CO 0.67 for 200 h. The results showed that the addition of small amounts of Al2O3 affects the activity of iron-based catalysts to a little extent. However, with further increase of Al2O3 content, the FTS activity and water gas shift reaction （WGS） activity are decreased severely. The addition of appropriate Al2O3 do not affect the product selectivity, but the catalysts incorporated with large amounts of Al2O3 have higher selectivity for light hydrocarbons and lower selectivity for heavy hydrocarbons.

关键词： Fischer-Tropsch synthesis iron-based catalyst Al2O3 binder Fe-Al2O3 interaction

Promoter effect on the CO_2-H_2O formation during Fischer-Tropsch synthesis on iron-based catalysts

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Journal of Natural Gas Chemistry 2010年第2期19卷 193-197页

作者： Ali Nakhaei Pour Seyed Mehdi Kamali Shahri Yahya Zamani Akbar Zamanian Research Institute of Petroleum Industry (RIPI) of National Iranian Oil Company Gas Research DivisionP.O.Box 14665-137TehranIran

The effects of Mg,La and Ca promoters on primary and secondary CO2 and H2O formation pathways during Fischer-Tropsch synthesis on precipitated Fe/Cu/SiO2 catalysts are *** chemisorbed oxygen atoms in the primary pathway formed in the CO dissociation steps reacted with co-adsorbed hydrogen or carbon monoxide to produce H2O and CO2,*** secondary pathway was the water-gas shift *** results indicated that the CO2 production led to an increase in both primary and secondary pathways,and H2O production decreased when surface basicity of the catalyst increased in the order Ca 〉 Mg 〉 La.

关键词： Ca promoter Mg promoter La promoter Fischer-Tropsch synthesis iron-based catalyst water-gas shift reaction

Effect of Addition Sequence during Neutralization and Precipitation on iron-based catalysts for High Temperature Shift Reaction

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Petroleum Science 2007年第1期4卷 75-80页

作者： Li Wei Zhu Jianhua Mou Zhanjun Faculty of Chemical Science ＆ Engineering China University of Petroleum Beijing 102249 China Institute of Chemical Engineering Inner Mongolia University of Technology Hohhot 010051 China

The preparation of the iron-based catalysts promoted by cobalt with a small amount of copper and aluminum for the high temperature shift reaction （HTS） with different sequences of adding catalyst raw materials during neutralization and precipitation was investigated. XRD, BET and particle size distribution （PSD） were used to characterize the prepared catalysts. It was found that the catalyst crystals were all γ-Fe2O3, and the intermediate of the catalyst after aging was Fe3O4. The crystallographic form of the catalyst and its intermediate was not affected by the addition sequence in the neutralization and precipitation process. The results showed that the specific surface area and the particle size of the catalysts depended on the addition sequence to the mother liquor. Cobalt with a small amount of copper and aluminum could increase the specific surface area and decrease the particle size of catalysts.

关键词： Water gas shift reaction γ-Fe2O3 cobalt-promoted catalyst iron-based catalyst

Effect of nano-particle size on product distribution and kinetic parameters of Fe/Cu/La catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第2期19卷 107-116页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht Sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi University of MashhadP.O.Box 91775-1436MashhadIran Research Institute of Petroleum Industry of National Iranian Oil Company P.O.Box 14665-137TehranIran

Effects of nano-particle size on hydrocarbon production rates and distributions for precipitated Fe/Cu/La catalysts in Fischer-Tropsch synthesis were ***-structured iron catalyst was prepared by micro-emulsion *** concept of two superimposed AndersonSchulz-Flory （ASF） distributions has been applied for the representation of the effects of reaction conditions and nano-particles size on kinetics parameters and product *** results reveal that by reducing the particle size of catalyst,the break in ASF distributions was *** useful different kinetics equations for synthesis of C3 to C9 and C10 to C22 were determined by using α1 and α2 chain growth probabilities.

关键词： chain length distribution Fischer-Tropsch synthesis iron-based catalyst nano-particle size

The performance and mechanism of iron-mediated chemical oxidation:Advances in hydrogen peroxide,persulfate and percarbonate oxidation

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Journal of Environmental Sciences 2023年第6期128卷 181-202页

作者： Mengqi Han Hui Wang Wei Jin Wenhai Chu Zuxin Xu State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China Ministry of Education Key Laboratory of Yangtze River Water Environment Tongji UniversityShanghai 200092China International Joint Research Center for Sustainable Urban Water System Tongji UniversityShanghai 200092China

Many studies have successfully built iron-mediatedmaterials to activate or catalyze Fentonlike reactions,with applications in water and wastewater treatment being ***,the developed materials are rarely compared with each other regarding their performance of organic contaminant *** this review,the recent advances of Fentonlike processes in homogeneous and heterogeneous ways are summarized,especially the performance and mechanism of activators including ferrous iron,zero valent iron,iron oxides,iron-loaded carbon,zeolite,and metal organic framework ***,this work mainly compares three O-O bond containing oxidants including hydrogen dioxide,persulfate,and percarbonate,which are environmental-friendly oxidants and feasible for in-situ chemical *** influence of reaction conditions,catalyst properties and benefits are analyzed and *** addition,the challenges and strategies of these oxidants in applications and the major mechanisms of the oxidation process have been *** work can help understand the mechanistic insights of variable Fenton-like reactions,the role of emerging iron-based materials,and provide guidance for choosing appropriate technologies when facing real-world water and wastewater applications.

关键词： Fenton-like reactions iron-based catalyst Activation mechanism Chemical oxidation

Fischer-Tropsch synthesis by nano-structured iron catalyst

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Journal of Natural Gas Chemistry 2010年第3期19卷 284-292页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht Sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi University of Mashhad Research Institute of Petroleum Industry of National Iranian Oil Company Gas Research Division

Effects of nanoscale iron oxide particles on textural structure,reduction,carburization and catalytic behavior of precipitated iron catalyst in Fischer-Tropsch synthesis（FTS） are *** iron catalysts were prepared by microemulsion method in two ***,Fe2O3 ,CuO and La2O3 nanoparticles were prepared separately and were mixed to attain Fe/Cu/La nanostructured catalyst（sep-nano catalyst）;Secondly nanostructured catalyst was prepared by co-precipitation in a water-in-oil microemulsion method（mix-nano catalyst）.Also,conventional iron catalyst was prepared with common co-precipitation *** characterizations of the catalysts were performed by TEM,XRD,H2 and CO-TPR *** size of iron oxides for sep-nano and mix-nano catalysts,which were determined by XRD pattern（Scherrer equation） and TEM images was about 20 and 21.6 nm,*** evaluation was conducted in a fixed-bed stainless steel reactor and compared with conventional iron *** results revealed that FTS reaction increased while WGS reaction and olefin/paraffin ratio decreased in nanostructured iron catalysts.

关键词： Fischer-Tropsch synthesis iron-based catalyst nano-particle

Deactivation studies of nano-structured iron catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第3期19卷 333-340页

A nano-structured iron catalyst for syngas conversion to hydrocarbons in Fischer-Tropsch synthesis（FTS） was prepared by micro-emulsion *** of bulk iron phase and phase transformations of carbonaceous species during catalyst deactivation in FTS reaction were characterized by temperature-programmed surface reaction with hydrogen（TPSR-H 2 ）,and XRD *** carbonaceous species on surface and bulk of the nano-structured iron catalysts were completely identified by combined TPSR-H 2 and XRD spectra and which were compared with those recorded on conventional co-precipitated iron *** results reveal that the catalyst deactivation results from the formation of inactive carbide phases and surface carbonaceous species like graphite,and it will be increased when the particle size of iron oxides was reduced in FTS iron catalyst.

关键词： Fischer-Tropsch synthesis iron-based catalyst catalyst deactivation nano-size particles

Effect of Sulfate on an iron Manganese catalyst for Fischer-Tropsch Synthesis

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Journal of Natural Gas Chemistry 2007年第4期16卷 354-362页

作者： Tingzhen Li Yong Yang Zhichao Tao Haijun Wan Xia An Chenghua Zhang Hongwei Xiang Yongwang Li State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Taiyuan 030001 Shanxi China Graduate University of the Chinese Academy of Sciences Beijing 100029 China

The effect of sulfate on Fischer-Tropsch synthesis performance was investigated in a slurryphase continuously stirred tank reactor （CSTR） over a Fe-Mn catalyst. The physiochemical properties of the catalyst impregnated with different levels of sulfate were characterized by N2 physisorption, X-ray photoelectron spectroscopy （XPS）, H2 （or CO） temperature-programmed reduction （TPR）, Mossbauer spectroscopy, and CO2 temperature-programmed desorption （TPD）. The characterization results indicated that the impregnated sulfate slightly decreased the BET surface area and pore volume of the catalyst, suppressed the catalyst reduction and carburization in CO and syngas, and decreased the catalyst surface basicity. At the same time, the addition of small amounts of sulfate improved the activities of FischerTropsch synthesis （FTS） and water gas shift （WGS）, shifted the product to light hydrocarbons （C1-C11） and suppressed the formation of heavy products （C12＋）. Addition of SO4^2- to the catalyst improved the FTS activity at a sulfur loading of 0.05-0.80 g per 100 g Fe, and S-05 catalyst gave the highest CO conversion （62.3%）, and beyond this sulfur level the activity of the catalyst decreased.

关键词： Fischer-Tropsch synthesis iron-based catalyst sulfate content ferrous sulfate manganese

Size dependence of carbon-encapsulated iron-based nanocatalysts for Fischer–Trposch synthesis

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Nano Research 2023年第5期16卷 6270-6277页

作者： Xiaoxue Han Jing Lv Shouying Huang Qiao Zhao Yue Wang Zhenhua Li Xinbin Ma Key Laboratory for Green Chemical Technology of Ministry of Education School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Zhejiang Institute of Tianjin University Ningbo 315201China Haihe Laboratory of Sustainable Chemical Transformations Tianjin 300192China

The conversion from syngas derived from non-petroleum recourses to liquid fuels and chemicals via Fischer–Tropsch synthesis(FTS)is regarded as an alternative and potential *** catalyst with controllable particle size and clarifying size effect are of significance to promote the ***,we engineered carbon-encapsulation structure to restrict particle growth but avoid strong metal–support *** prepared carbon-encapsulated nanoparticles(Fe@C)showed a superior catalytic activity compared with conventional carbon-supported nanoparticles(Fe/C).By tuning particle size from 3.0 to 9.1 nm,a volcano-like trend of iron time yield(FTY)peaked at 2659μmol·gFe^(−1)·s^(−1)is obtained with an optimum particle size of 5.3 *** to temperature-programmed reduction and desorption results,a linear relationship between apparent turnover frequency and CO dissociation capacity was *** enhanced CO dissociative adsorption along with weakened H_(2)activation on larger nanoparticles resulted in higher C_(5+)*** study provides a strategy to synthesize carbon supported metal catalysts with controllable particle size and insight into size effect on Fe-based catalytic FTS.

关键词： Fischer–Tropsch synthesis iron-based catalyst carbon-encapsulation size effect