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Review of Iron-Based Catalysts for Carbon Dioxide Fischer-Tropsch Synthesis
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作者 Ji-Yue Jia Yu-Ling Shan +3 位作者 Yong-Xiao Tuo Hao Yan Xiang Feng De Chen 《Transactions of Tianjin University》 EI CAS 2024年第2期178-197,共20页
Capturing and utilizing CO_(2)from the production process is the key to solving the excessive CO_(2)emission problem. CO_(2)hydrogenation with green hydrogen to produce olefins is an effective and promising way to uti... Capturing and utilizing CO_(2)from the production process is the key to solving the excessive CO_(2)emission problem. CO_(2)hydrogenation with green hydrogen to produce olefins is an effective and promising way to utilize CO_(2)and produce valuable chemicals. The olefins can be produced by CO_(2)hydrogenation through two routes, i.e., CO_(2)-FTS (carbon dioxide Fischer- Tropsch synthesis) and MeOH (methanol-mediated), among which CO_(2)-FTS has significant advantages over MeOH in practical applications due to its relatively high CO_(2)conversion and low energy consumption potentials. However, the CO_(2)-FTS faces challenges of difficult CO_(2)activation and low olefins selectivity. Iron-based catalysts are promising for CO_(2)-FTS due to their dual functionality of catalyzing RWGS and CO-FTS reactions. This review summarizes the recent progress on iron-based catalysts for CO_(2)hydrogenation via the FTS route and analyzes the catalyst optimization from the perspectives of additives, active sites, and reaction mechanisms. Furthermore, we also outline principles and challenges for rational design of high-performance CO_(2)-FTS catalysts. 展开更多
关键词 CO_(2)hydrogenation OLEFINS CO_(2)-FTS iron-based catalysts
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A critical review towards the causes of the iron-based catalysts deactivation mechanisms in the selective oxidation of hydrogen sulfide to elemental sulfur from biogas
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作者 Mostafa Tarek Janaina S.Santos +4 位作者 Victor Márquez Mohammad Fereidooni Mohammad Yazdanpanah Supareak Praserthdam Piyasan Praserthdam 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第3期388-411,I0010,共25页
Hydrogen sulfide(H_(2)S) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low concentrations.Among various technologies,the selective oxidation of ... Hydrogen sulfide(H_(2)S) not only presents significant environmental concerns but also induces severe corrosion in industrial equipment,even at low concentrations.Among various technologies,the selective oxidation of hydrogen sulfide(SOH_(2)S) to elemental sulfur(S) has emerged as a sustainable and environmentally friendly solution.Due to its unique properties,iron oxide has been extensively investigated as a catalyst for SOH_(2)S;however,rapid deactivation has remained a significant drawback.The causes of iron oxide-based catalysts deactivation mechanisms in SOH_(2)S,including sulfur or sulfate deposition,the transformation of iron species,sintering and excessive oxygen vacancy formation,and active site loss,are thoroughly examined in this review.By focusing on the deactivation mechanisms,this review aims to provide valuable insights into enhancing the stability and efficiency of iron-based catalysts for SOH_(2)S. 展开更多
关键词 Selective oxidation of H_(2)S iron-based catalysts Mechanism of deactivation Sulfur or sulfate deposition Transformation of iron species Sintering SDG 7
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Boosting Fischer-Tropsch Synthesis via Tuning of N Dopants in TiO_(2)@CN-Supported Ru Catalysts 被引量:1
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作者 Xincheng Li Yunhao Liu +10 位作者 Dejian Zhao Shuaishuai Lyu Jingwei Ye Xiaoshen Li Peipei Wu Ye Tian Yingtian Zhang Tong Ding Song Song Qingpeng Cheng Xingang Li 《Transactions of Tianjin University》 EI CAS 2024年第1期90-102,共13页
Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such ... Nitrogen(N)-doped carbon materials as metal catalyst supports have attracted signifi cant attention,but the eff ect of N dopants on catalytic performance remains unclear,especially for complex reaction processes such as Fischer-Tropsch synthesis(FTS).Herein,we engineered ruthenium(Ru)FTS catalysts supported on N-doped carbon overlayers on TiO_(2)nanoparticles.By regulating the carbonization temperatures,we successfully controlled the types and contents of N dopants to identify their impacts on metal-support interactions(MSI).Our fi ndings revealed that N dopants establish a favorable surface environment for electron transfer from the support to the Ru species.Moreover,pyridinic N demonstrates the highest electron-donating ability,followed by pyrrolic N and graphitic N.In addition to realizing excellent catalytic stability,strengthening the interaction between Ru sites and N dopants increases the Ru^(0)/Ru^(δ+)ratios to enlarge the active site numbers and surface electron density of Ru species to enhance the strength of adsorbed CO.Consequently,it improves the catalyst’s overall performance,encompassing intrinsic and apparent activities,as well as its ability for carbon chain growth.Accordingly,the as-synthesized Ru/TiO_(2)@CN-700 catalyst with abundant pyridine N dopants exhibits a superhigh C_(5+)time yield of 219.4 mol CO/(mol Ru·h)and C_(5+)selectivity of 85.5%. 展开更多
关键词 fischer-tropsch synthesis N-doped carbon materials Ruthenium catalyst Pyridinic N Metal-N interaction
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Effect of Al_2O_3 Binder on the Precipitated Iron-Based Catalysts for Fischer-Tropsch Synthesis 被引量:6
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作者 Hai-Jun Wan Bao-Shan Wu +4 位作者 Xia An Ting-Zhen Li Zhi-Chao Tao Hong-Wei Xiang Yong-Wang Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第2期130-138,共9页
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 characteriz... 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. 展开更多
关键词 fischer-tropsch synthesis iron-based catalyst Al2O3 binder Fe-Al2O3 interaction
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Promoter effect on the CO_2-H_2O formation during Fischer-Tropsch synthesis on iron-based catalysts 被引量:1
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作者 Ali Nakhaei Pour Seyed Mehdi Kamali Shahri +1 位作者 Yahya Zamani Akbar Zamanian 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第2期193-197,共5页
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 investigated.The chemisorbed oxygen atoms in the ... 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 investigated.The 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,respectively.The secondary pathway was the water-gas shift reaction.The 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. 展开更多
关键词 Ca promoter Mg promoter La promoter fischer-tropsch synthesis iron-based catalyst water-gas shift reaction
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Effect of Manganese Incorporation Manner on an Iron-Based Catalyst for Fischer-Tropsch Synthesis 被引量:5
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作者 Tingzhen Li Yong Yang +5 位作者 Chenghua Zhang Zhichao Tao Haijun Wan Xia An Hongwei Xiang Yongwang Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第3期244-251,共8页
A systematic study was undertaken to investigate the effects of the manganese incorporation manner on the textural properties, bulk and surface phase compositions, reduction/carburization behaviors, and surface basici... A systematic study was undertaken to investigate the effects of the manganese incorporation manner on the textural properties, bulk and surface phase compositions, reduction/carburization behaviors, and surface basicity of an iron-based Fischer-Tropsch synthesis (FTS) catalyst. The catalyst samples were characterized by N2 physisorption, X-ray photoelectron spectroscopy (XPS), H2 (or CO) temperature-programmed reduction (TPR), CO2 temperature-programmed desorption (TPD), and M5ssbauer spectroscopy. The FTS performance of the catalysts was studied in a slurry-phase continuously stirred tank reactor (CSTR). The characterization results indicated that the manganese promoter incorporated by using the coprecipitation method could improve the dispersion of iron oxide, and decrease the size of the iron oxide crystallite. The manganese incorporated with the impregnation method is enriched on the catalyst's surface. The manganese promoter added with the impregnation method suppresses the reduction and carburization of the catalyst in H2, CO, and syngas because of the excessive enrichment of manganese on the catalyst surface. The catalyst added manganese using the coprecipitation method has the highest CO conversion (51.9%) and the lowest selectivity for heavy hydrocarbons (C12+). 展开更多
关键词 fischer-tropsch synthesis iron-based catalyst manganese promoter incorporation manner
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Study of Manganese Promoter on a Precipitated Iron-Based Catalyst for Fischer-Tropsch Synthesis 被引量:10
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作者 Zhichao Tao Yong fang +4 位作者 Chenghua Zhang Tingzhen Li Mingyue Ding Hongwei Xiang Yongwang Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2007年第3期278-285,共8页
The effects of Manganese (Mn) incorporation on a precipitated iron-based Fischer-Tropsch synthesis (FTS) catalyst were investigated using N2 physical adsorption, air differential thermal analysis (DTA), H2 tempe... The effects of Manganese (Mn) incorporation on a precipitated iron-based Fischer-Tropsch synthesis (FTS) catalyst were investigated using N2 physical adsorption, air differential thermal analysis (DTA), H2 temperature-programmed reduction (TPR), and Mǒssbauer spectroscopy. The FTS performances of the catalysts were tested in a slurry phase reactor. The characterization results indicated that Mn increased the surface area of the catalyst, and improved the dispersion of (α-Fe2O3 and reduced its crystallite size as a result of the high dispersion effect of Mn and the Fe-Mn interaction. The Fe-Mn interaction also suppressed the reduction of (α-Fe2O3 to Fe3O4, stabilized the FeO phase, and (or) decreased the carburization degree of the catalysts in the H2 and syngas reduction processes. In addition, incorporated Mn decreased the initial catalyst activity, but improved the catalyst stability because Mn restrained the reoxidation of iron carbides to Fe3O4, and improved further carburization of the catalysts. Manganese suppressed the formation of CH4 and increased the selectivity to light olefins (C2-4^=), but it had little effect on the selectivities to heavy (C5+) hydrocarbons. All these results indicated that the strong Fe-Mn interaction suppressed the chemisorptive effect of the Mn as an electronic promoter, to some extent, in the precipitated iron-manganese catalyst system. 展开更多
关键词 fischer-tropsch synthesis iron-manganese catalyst manganese promoter Fe-Mn interaction
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Effect of Addition Sequence during Neutralization and Precipitation on Iron-based Catalysts for High Temperature Shift Reaction 被引量:1
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作者 Li Wei Zhu Jianhua Mou Zhanjun 《Petroleum Science》 SCIE CAS CSCD 2007年第1期75-80,共6页
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 durin... 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. 展开更多
关键词 Water gas shift reaction Γ-FE2O3 cobalt-promoted catalyst iron-based catalyst
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Effects of zinc on Fe-based catalysts during the synthesis of light olefins from the Fischer-Tropsch process 被引量:10
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作者 高新华 张建利 +4 位作者 陈宁 马清祥 范素兵 赵天生 椿范立 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期510-516,共7页
Fe‐based catalysts for the production of light olefins via the Fischer‐Tropsch synthesis were modi‐fied by adding a Zn promoter using both microwave‐hydrothermal and impregnation methods. The physicochemical prope... Fe‐based catalysts for the production of light olefins via the Fischer‐Tropsch synthesis were modi‐fied by adding a Zn promoter using both microwave‐hydrothermal and impregnation methods. The physicochemical properties of the resulting catalysts were determined by scanning electron mi‐croscopy, the Brunauer‐Emmett‐Teller method, X‐ray diffraction, H2 temperature‐programed re‐duction and X‐ray photoelectron spectroscopy. The results demonstrate that the addition of a Zn promoter improves both the light olefin selectivity over the catalyst and the catalyst stability. The catalysts prepared via the impregnation method, which contain greater quantities of surface ZnO, exhibit severe carbon deposition following activity trials. In contrast, those materials synthesized using the microwave‐hydrothermal approach show improved dispersion of Zn and Fe phases and decreased carbon deposition, and so exhibit better CO conversion and stability. 展开更多
关键词 Zn promoter Fe-based catalyst Light olefin fischer-tropsch synthesis Microwave-hydrothermal method
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A facile solvent-free synthesis strategy for Co-imbedded zeolite-based Fischer-Tropsch catalysts for direct gasoline production 被引量:5
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作者 Mudassar Javed Shilin Cheng +7 位作者 Guihua Zhang Cederick Cyril Amoo Jingyan Wang Peng Lu Chengxue Lu Chuang Xing Jian Sun Noritatsu Tsubaki 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期604-612,共9页
A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with t... A series of Co-imbedded zeolite-based catalysts were synthesized following a facile solvent-free grinding route.The catalytic performance for direct syngas conversion to gasoline range hydrocarbons was compared with their counterpart Co-impregnated zeolite-based catalysts.Successful transformation of solid raw materials to targeted zeolite was confirmed by XRD,SEM,STEM,and N2 physisorption analysis.An in-depth study of acidic strength and acidic site distribution was conducted by NH3-TPD and Py-IR spectroscopy.Acidic strength showed a pivotal role in defining product range.Co@S1,with the weakest acidic strength of silicalite-1 among three types of zeolites,evaded over-cracking of product and exhibited the highest gasoline and isoparaffin selectivity(≈70%and 30.7%,respectively).Moreover,the solvent-free raw material grinding route for zeolite synthesis accompanies several advantages like the elimination of production of wastewater,high product yield within confined crystallization space,and elimination of safety concerns regarding high pressure due to the absence of the solvent.Facileness and easiness of the solvent-free synthesis route together with promising catalytic performance strongly support its application on the industrial scale. 展开更多
关键词 Solvent-free synthesis Co-imbedded zeolite catalyst fischer-tropsch synthesis Gasoline ISOPARAFFIN
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Study on iron-manganese catalysts for Fischer-Tropsch synthesis 被引量:5
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作者 MOSTAFA FEYZI FATANEH JAFARI 《燃料化学学报》 EI CAS CSCD 北大核心 2012年第5期550-557,共8页
铁锰催化剂被一起沉淀方法准备。催化剂的描述被使用 X 光衍射(XRD ) 执行,扫描电子显微镜学(SEM ) ,温度程序减小(TPR ) , N2 吸附解吸附作用大小。从 Fischer-Tropsch 合成的催化表演测试的结果证明铁锰催化剂对催化剂作文和材料... 铁锰催化剂被一起沉淀方法准备。催化剂的描述被使用 X 光衍射(XRD ) 执行,扫描电子显微镜学(SEM ) ,温度程序减小(TPR ) , N2 吸附解吸附作用大小。从 Fischer-Tropsch 合成的催化表演测试的结果证明铁锰催化剂对催化剂作文和材料来源敏感过度。当 CH4 和 CO2 由使用从铁(II ) 准备的铁锰催化剂减少了时, C24 轻石蜡增加了,这被发现当 CH4 和 CO2 由使用从铁(II ) 准备的铁锰催化剂减少了时硫酸盐(催化剂) 。催化剂的活动和选择处于不同运作的条件被学习。结果证明为 C24 轻石蜡生产的最好的运作的条件在 260 点是 H2/CO=1/1 (GHSV=2400 h1 ) 展开更多
关键词 iron-manganese catalyst catalytic performance operational conditions fischer-tropsch synthesis
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Metal-organic framework(MOF)-derived catalysts for Fischer-Tropsch synthesis: Recent progress and future perspectives 被引量:3
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作者 Kabir Opeyemi Otun Xinying Liu Diane Hildebrandt 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期230-245,共16页
Fischer-Tropsch Synthesis(FTS) is an important catalytic chemical reaction that converts a mixture of CO and H2(syngas) derived from biomass, coal or natural gas into ultra-clean fuels or value-added chemicals. Howeve... Fischer-Tropsch Synthesis(FTS) is an important catalytic chemical reaction that converts a mixture of CO and H2(syngas) derived from biomass, coal or natural gas into ultra-clean fuels or value-added chemicals. However, most traditional catalysts used in the Fischer-Tropsch process are faced with the problems of high deactivation rate triggered by sintering, phase changes and oxidation which hamper their catalytic performance. Metal-organic frameworks(MOFs)-derived materials have been a promising alternative in addressing the catalyst deactivation problems in FTS because of the encapsulation of their metal nanoparticles in carbon matrix and absence of large particle size, among other reasons. Therefore, this review emphasizes the most recent research headway in the investigation of MOFs as precursors to achieve high-performance FTS catalysts. Precisely, the design of iron and cobalt-based FTS catalysts from parent MOFs via MOF-mediated synthesis, the catalytic activity of the MOF-derived materials and the promoter effects under FTS operation were outlined and discussed. We have also evaluated the influence of MOF structures on the FTS performance and compared them with traditional/commercially available catalysts to show the importance of this approach. Finally, the challenges and opportunities to further expedite the extensive research efforts and promote their applications in material design and FT technology were mentioned. 展开更多
关键词 Metal-organic frameworks fischer-tropsch synthesis catalyst MOFMS DEACTIVATION
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Active Fischer-Tropsch synthesis Fe-Cu-K/SiO_2 catalysts prepared by autocombustion method without a reduction step 被引量:1
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作者 Suthasinee Pengnarapat Peipei Ai +3 位作者 Prasert Reubroycharoen Tharapong Vitidsant Yoshiharu Yoneyama Noritatsu Tsubaki 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第2期432-438,共7页
The purpose of this study was to prepare iron-based catalysts supported on silica by autocombustion method for directly using for Fischer-Tropsch synthesis(FTS) without a reduction step. The effect of different citr... The purpose of this study was to prepare iron-based catalysts supported on silica by autocombustion method for directly using for Fischer-Tropsch synthesis(FTS) without a reduction step. The effect of different citric acid(CA):iron nitrate(N) molar ratios and acid types on the FTS performance of catalysts were investigated. The CA:N molar ratios had an important influence on the formation of iron active phases and FTS activity. The iron carbide(FexC), which is known to be one of the iron active phases, was demonstrated by the X-ray diffraction and X-ray photoelectron spectroscopy. Increasing the CA:N molar ratios up to 0.1 increased CO conversion of catalyst to 86.5%, which was then decreased markedly at higher CA:N molar ratios. An excess of CA resulted in carbon residues covering the catalyst surface and declined FTS activity. The optimal catalyst(CA:N molar ratio = 0.1) achieved the highest CO conversion when compared with other autocombustion catalysts as well as reference catalyst prepared by impregnation method, followed by a reduction step. The autocombustion method had the advantage to synthesize more efficient catalysts without a reduction step. More interestingly, iron-based FTS catalysts need induction duration at the initial stage of FTS reaction even after reduction, because metallic iron species need time to be transformed to FexC. But here, even if without reduction, FexC was formed directly by autocombustion and induction period was eliminated during FTS reaction. 展开更多
关键词 fischer-tropsch synthesis iron-based catalysts Autocombustion Iron carbide SIO2
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Effect of operating conditions and potassium content on Fischer-Tropsch liquid products produced by potassium-promoted iron catalysts 被引量:1
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作者 Francisco E.M.Farias Fernando G.Sales Fabiano A.N.Fernandes 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期175-178,共4页
The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium mola... The dependencies of Fischer-Tropsch synthesis liquid hydrocarbon product distribution on operating pressure and temperature have been studied over three potassium-promoted iron catalysts with increasing potassium molar content. The study followed an experimental planning and the results were analyzed based on surface response methodology. The effects of different operating conditions and potassium contents on the liquid product distribution were compared based on number average carbon number and dispersion. Results showed that high pressures (25 to 30 arm) favored the production of waxes that could be converted into liquid fuels through hydrocracking, while greater direct selectivity towards diesel was favored by low pressure (20 arm) using catalysts with low potassium to iron molar ratios. The liquid product distribution produced using an iron catalyst with high potassium content presented higher number-average number of carbons when compared to the distribution obtained using an iron catalyst with low potassium content. 展开更多
关键词 fischer-tropsch synthesis liquid fuels iron-based catalyst POTASSIUM
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Influence of lanthanum on the performance of Zr-Co/activated carbon catalysts in Fischer-Tropsch synthesis 被引量:2
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作者 Tao Wang Yunjie Ding +2 位作者 Yuan Lu Hejun Zhu Liwu Lin 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期153-158,共6页
The influence of La loading on Zr-Co/activated carbon (AC) catalysts has been studied for Fischer-Tropsch synthesis. The catalyst samples were characterized by XRD, TPR, CO-TPD, and temperature programmed CO hydroge... The influence of La loading on Zr-Co/activated carbon (AC) catalysts has been studied for Fischer-Tropsch synthesis. The catalyst samples were characterized by XRD, TPR, CO-TPD, and temperature programmed CO hydrogenation. The catalytic property was evaluated in a fixed bed reactor. The experimental results showed that CO conversion increased from 86.4% to 92.3% and the selectivity to methane decreased from 14.2% to 11.5% and C5+ selectivity increased from 71.0% to 74.7% when low La loading (La = 0.2wt%) was added into the Zr-Co/AC catalyst. However, high loadings of La (La = 0.3-1.0 wt%) would decrease catalyst activity as well as the C5+ selectivity and increase methane selectivity. XRD results displayed that La-modified Zr-Co/AC catalyst had little effect on the dispersion of Co catalyst. But, the results of TPR, CO-TPD, and temperature programmed CO hydrogenation techniques indicated that the extent of cobalt reduction was found to greatly influence the activity and selectivity of the catalyst. The addition of a small amount of La increased the reducibility of the Zr-Co/AC catalyst and restrained the formation of methane and improved the selectivity to long chain hydrocarbons. However, excess of La led to the decrease of the reducibility of Co catalyst thus resulted in higher methanation activity. 展开更多
关键词 lanthanum promoter fischer-tropsch synthesis Zr-Co/AC catalyst REDUCIBILITY
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Effect of incorporation manner of Zr promoter on precipitated ironbased catalysts for Fischer-Tropsch synthesis 被引量:2
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作者 ZHANG Hao-jian MA Hong-fang +2 位作者 ZHANG Hai-tao YING Wei-yong FANG Ding-ye 《Journal of Coal Science & Engineering(China)》 2012年第2期182-187,共6页
The promotional effects of Zr on the structure, reduction, carburization and catalytic behavior of precipitated iron-based Fischer-Tropsch synthesis (FTS) catalysts were investigated. The catalysts were characterize... The promotional effects of Zr on the structure, reduction, carburization and catalytic behavior of precipitated iron-based Fischer-Tropsch synthesis (FTS) catalysts were investigated. The catalysts were characterized by N2 physisorption, temperature-programmed reduction (TPR), and M6ssbauer effect spectroscopy (MES) techniques. As revealed by N2 physisorption, Zr decreased the BET surface area and pore volume of the catalyst. The results of TPR and MES show that Zr suppresses the reduction and carburization of Fe catalysts because of the interaction between Fe and Zr. The FTS reaction results indicate that Zr decreases the FTS activity of Fe catalysts but improves the catalysts' stability. In addition, Zr promoter restraines the formation of light hydrocarbons (methane and C2-C4) and shifts the production distribution to the heavy hydrocarbons. 展开更多
关键词 Zr promoter precipitated iron-based catalyst fischer-tropsch synthesis
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Effect of mass transfer limitations on catalyst performance during reduction and carburization of iron based Fischer-Tropsch synthesis catalysts 被引量:1
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作者 Akbar Zamaniyan Yadollah Mortazavi +1 位作者 Abbas Ali Khodadadi Ali Nakhaei Pour 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2013年第5期795-803,共9页
Existence of intraparticle mass transfer limitations under typical Fischer-Tropsch synthesis has been reported previously,but there is no suitable study on the existence of intraparticle diffusion limitations under pr... Existence of intraparticle mass transfer limitations under typical Fischer-Tropsch synthesis has been reported previously,but there is no suitable study on the existence of intraparticle diffusion limitations under pretreatment steps (reduction and activation) and their effect on catalytic performance for iron based catalysts.In this study,Fe-Cu-La-SiO2 catalysts were prepared by co-precipitation method.To investigate the intraparticle mass transfer limitation under reduction,activation and reaction steps,and its effect on catalytic performance,catalyst pellets with different sizes of 6,3,1 and 0.5 mm have been prepared.All catalysts were calcined,pretreated and tested under similar conditions.The catalysts were activated in hydrogen (5%H2in N2) at 450℃ for 3 h and exposed to syngas (H2/CO=1) at 270℃ and atmospheric pressure for 40 h.Afterwards,FTS reaction tests were performed for approximately 120 h to reach steady state conditions at 290℃,17 bar and a feed flow (syngas H2/CO=1) rate of 3 L/h (STP).Using small pellets resulted in higher CO conversion,FT reaction rate and C5+ productivity as compared with larger pellets.The small pellets reached steady state conditions just 20 h after starting the reaction.Whereas for larger pellets,CO conversion,FT reaction rate and C5+ productivity increased gradually,and reached steady state and maximum values after 120 h of operation.The results illustrate that mass transfer limitations exist not only for FTS reaction but also for the reduction and carburization steps which lead to various phase formation through catalyst activation.Also the results indicate that some effects of mass transfer limitations in activation step,can be compensated in the reaction step.The results can be used for better design of iron based catalyst to improve the process economy. 展开更多
关键词 fischer-tropsch mass transfer limitation activation catalyst GTL
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Controllable synthesis of core-shell Co@C@SiO2 catalysts for enhancing product selectivity in Fischer-Tropsch synthesis by tuning the mass transfer resistance 被引量:1
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作者 Yao Chen Xin Li +5 位作者 Liya Dai Mehar U Nisa Chengchao Liu Shuai Lv Jing Lv Zhenhua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2020年第12期199-206,共8页
Fischer-Tropsch synthesis(FTS) is the key step in converting syngas into clean fuels. Traditional supported catalysts for FTS are problematic because the active metal crystalline size is positively related to metal lo... Fischer-Tropsch synthesis(FTS) is the key step in converting syngas into clean fuels. Traditional supported catalysts for FTS are problematic because the active metal crystalline size is positively related to metal loading. Therefore, increasing active metal loading may reduce the cobalt time yield(CTY) since a high CTY is usually obtained when the Co size is 8 nm. Here, a ZIF-67(Zeolitic imidazolate framework-67) with a MOF(Metal organic framework) structure is used as a precursor to prepare the Co@C catalyst with not only high cobalt loading(55.6 wt%) but also with a small cobalt crystal size(as small as 8.6 nm). Coreshell Co@C@SiO2-X catalysts with different SiO2 shell thicknesses were successfully prepared by coating different amounts of TEOS on the outer surface of Co@C to modify product selectivity. Compared with40 wt% Co/SiO2 catalyst, core-shell Co@C@SiO2-X catalysts exhibited improved FTS performance. Furthermore, different gaseous hourly space velocities(GHSVs) were used to obtain CO conversion at similar levels to compare CTY and the turnover frequency(TOF). Among the catalysts, the Co@C@SiO2-1 catalyst, with its better mass transfer ability and suitable hydrophilic property, presented the highest TOF(9.75 × 10-3 s-1) and lowest CH4 selectivity(9.75%). In addition, heavy hydrocarbons were effectively suppressed with the increase in shell thickness due to the increased mass transfer resistance. 展开更多
关键词 fischer-tropsch synthesis ZIF-67 Product selectivity Core-shell catalyst Hydrophilic property
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Ruthenium promotion of Co/SBA-15 catalysts for Fischer-Tropsch synthesis in slurry-phase reactors 被引量:1
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作者 Jocielys Jovelino Rodrigues Gina Pecchi +1 位作者 Fabiano AndrNarciso Fernandes Meiry Glucia Freire Rodrigues 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期722-728,共7页
The aim of this work was to evaluate the catalytic properties of a Ru promoted Co/SBA-15 catalyst for Fischer-Tropsch synthesis (FTS). The Ru promoted Co/SBA-15 catalyst was prepared by wet impregnation method and w... The aim of this work was to evaluate the catalytic properties of a Ru promoted Co/SBA-15 catalyst for Fischer-Tropsch synthesis (FTS). The Ru promoted Co/SBA-15 catalyst was prepared by wet impregnation method and was characterized by X-ray diffraction, X-ray energy dispersion spectrophotometer, N2 adsorption-desorption, temperature-programmed reduction and transmission electron microscopy. The Fischer-Tropsch synthesis using the catalyst was carried out to evaluate the catalyst activity and its effect on FTS product distribution. The synthesis was carried out in a slurry reactor operating at 513 K, 20 atm, CO : H2 molar ratio of 1 : 1. X-ray diffraction showed that the calcined cobalt catalyst did not modify the structure of SBA-15, proving that Co was present in the form of Co3O4 in the catalyst. The addition of cobalt in SBA-15 decreased the specific superficial area of the molecular sieve. Fischer-Tropsch synthesis activity and C5+ hydrocarbon selectivity increased with the addition of Ru. The increases in activity and selectivity were attributed to the increased number of active sites resulting from higher reducibility and the synergetic effect of Ru and Co. Ru/Co/SBA-15 catalysts showed moderate conversion (40%) and high selectivity towards the production of C5+ (80 wt%). 展开更多
关键词 SBA-15 cobalt RUTHENIUM heterogeneous catalyst slurry reactor fischer-tropsch synthesis
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Fischer-Tropsch Synthesis over Alumina- Supported Cobalt-Based Catalysts: Effect of Support Variables 被引量:1
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作者 Yan Liu Heqin Guo +6 位作者 Litao Jia Zhancheng Ma Yong Xiao Congbiao Chen Ming Xia Bo Hou Debao Li 《Journal of Materials Science and Chemical Engineering》 2014年第12期19-27,共9页
Different kinds of aluminum precursors were obtained from precipitating ammonium bicarbonate, ammonium carbonate, and saturated ammonium bicarbonate, then, boehmite (AlO(OH)), ammonium alumina carbonate hydroxide (AAC... Different kinds of aluminum precursors were obtained from precipitating ammonium bicarbonate, ammonium carbonate, and saturated ammonium bicarbonate, then, boehmite (AlO(OH)), ammonium alumina carbonate hydroxide (AACH) and their mixture were obtained, and then, different kinds of alumina were obtained after calcination. Three catalysts supported on the different alumina were obtained via impregnating cobalt and ruthenium by incipient wetness. The effects of different precipitants on composition of precursors were?studied by XRD, FTIR, and TGA. The property and structure of alumina were studied by XRD and BET. The supported catalysts were studied by characterizations of XRD and H2-TPR, and the catalytic performance for Fischer-Tropsch synthesis (FTS) were evaluated at a fix-bed reactor. The relations among the composition of precursors, the property of alumina and the catalytic performance of supported catalysts were researched thoroughly. 展开更多
关键词 Cobalt-Based catalysts fischer-tropsch Synthesis ALUMINA PRECIPITANT
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