共查询到19条相似文献,搜索用时 140 毫秒
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应用XRD,XPS,Mossbauer谱,TPR,CO化学吸附CO-TPD,CO+H2反应性能测试等手段研究了锰助剂对F-T合成制低碳烯烃Mn-Fe/ZrO2催化剂结构及催化性能的影响。结果表明,与Fe/Zr催化相比,加锰助剂后的催化剂F-T反应催化活性上升,甲烷选择性降低,低碳烯烃选择性增加。 相似文献
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氯丙烯在不同催化剂表面上吸附的TPD结果表明在TS-1上有三重附峰,而在TiO2/Silicalite上仅有单峰,H2O2或分子O2在催化剂表面吸附后,在脱附物种中可用质谱检测到原子O(16)物种;说明H2O2或分子O2在样品表面存在解离吸附;并发现解离子分子O2的活性很低,TS-1能同时吸附内烯和H2O2,而在SiO2/Silicalite表面的吸附却与吸附顺序有关,环氧化活性顺序如下:TS-1 相似文献
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氯丙烯在不同催化剂表面上吸附的TPD结果表明:在TS-1上有三重脱附峰,而在TiO2/Silicalite上仅有单峰。H_2O_2或分子O_2在催化剂表面吸附后,在脱附物种中可用质谱检测到原子O(16)物种;说明H_O_2或分子O_2在样品表面存在解离吸附;并发现解离分子O_2的活性很低。TS-1能同时吸附氯丙烯和H_2O_2,而在SiO_2/Silicalite表面的吸附却与吸附顺序有关。环氧化活性顺序如下:TS-1(TPAOH)>TS-1(TPABr+NaOH)>TiO_2/Silicalite。TS-1沸石的高氧化活性可能与H_2O_2吸附后表面原子O(16)的形成有关。 相似文献
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采用CO加氢反应、CO-TPD、CO/H2-TPSR及C2H2/H2-TPSR等手段,研究合成气制低碳烯烃反应K-Fe-MnO/MgO催化剂中MnO的助剂作用。结果表明MnO能大幅度提高低碳烯烃的选择性,尤其是乙烯的选择性;MnO能抑制催化剂表面的乙烯加氢,因而有利于提高低碳烯烃的选择性及烯/烷的比值。 相似文献
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应用XRD、XPS、Mossbauer谱、TPR、CO-TPD、CO+H2反应性能测量试等手段研究了CeO2对F-T合成制低碳烯烃Ce-Fe/ZrO2催化剂催化性能的影响。结果表明,与Fe/Zr催化剂相比,加铈助剂后的催化剂F-T反应催化活性明显上升。 相似文献
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Fe2O3/ZrO2催化剂上一氧化碳加氢反应制低碳烯烃Ⅱ.预处理条件对催化剂结构及性能的影响 总被引:3,自引:1,他引:3
用TPR,Mossbauer谱法,XPS,SRD及反应评价等手段了Fe2O3/ZrO2催化剂的还原行为,铁物种状态和CO加氢反应性能,结果表明,预处理条件明显影响Fe2O3/ZrO2催化剂表面铁原子的数量、铁锆间的相互作用,催化剂的物相变化以及C氢反应的催经性能,以Fe2O2/ZrO2经氢氩混合氯程序升温至753K还原生成的Fe-Zr-O物种为前身,在合成气中进一步还原得到的铁锆催化剂,具有较好的 相似文献
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用TPR,Mossbauer谱法,XPS,XRD及反应评价等手段研究了Fe2O3/ZrO2催化剂的还原行为、铁物种状态和CO加氢反应性能.结果表明,预处理条件明显影响Fe2O3/ZrO2催化剂表面铁原子的数量、铁锆间的相互作用、催化剂的物相变化以及CO加氢反应的催化性能.以Fe2O3/ZrO2经氢氟混合气程序升温至753K还原生成的Fe-Zr-O物种为前身,在合成气中进一步还原得到的铁锆催化剂,具有较好的F-T反应合成低碳烯烃的选择性. 相似文献
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PRODUCTION OF LIGHTOLEFINS FROM CO_2 HYDROGENATION OVER Fe/SILICALITE-2 CATALYST Ⅱ. PROMOTION EFFECT OF MnO PROMOTER 下载免费PDF全文
IntroductionItilasbeenshot'-nthattileadditionofMnOpromotertoFocatal}stcanresultinaremarkableimprovementinthesclectivit}'to11ghtalkenesforCOh}!drogenationll'l.Ho-c'cvcr.thecadetofMnOonCH4formationandCOconversionisvery'ambigUouslltolMoreover.MnOpromotergrca… 相似文献
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K-Fe-MnO/Silicalite-2 is a desirable catalyst for the production of light olefins from CO2 hydrogenation The activity can be improved greatly with increasing the Fe loading, and the selectivities to hydrocarbons rise with Fe loading increase However, an ambiguous effect of Fe loading on the selectivity of light olefin in hydrocarbon products is observed. The CO2 hydrogenation containing a two-step mechanism CO2+H2=CO+H2O, a reversible water gas shift reaction, and CO+(m/2n+1)H2 =1/nCnHm+H2O2, a Frscher-Tropsch reaction, is suggested by the results of CO2-TPD and CO2/H2-TPSR as well as CO/H2-TPSR characterizations. 相似文献
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XU Long-Ya WANG Qing-Xia XU Yi-De HUANG Jia-ShengDalian Institute of Chemical Physics Academia SinicaDalian Liaoning State Key Laboratory of CatalysisDalian Institute of Chemical Physics. Academia SinicaDalian Liaoning To whom correspondence should be addressed. 《天然气化学杂志》1995,(3)
The activity and the selectivity to light alkenes of silicalite-2 (Si-2) zeolite supported F'e catalyst tor CO hydrogenation can he improved obviously with the addition of K2O and MnO promoters. The results of CO hydrogenation, CO-TPD, CO/H2-TPSR, C2H4/H2-TPSR and C2H4/H2 pulse reaction over K-Fe-MnO/Si-2 catalysts clearly show that the K2O additive into Fe-MnO/Si-2 catalyst leads to a remarkable increase in both the capacity and strength of the strong CO ad-species that will produce much more |Cad| via their disproportionation at higher temperatures. This results in an increase in the CO conversion and the selectivity to light olefins, and a decrease in CH4 formation. Moreover, K2O can suppress the disproportionate of C2H4 that occurs during the reaction as a side-reaction Meanwhile, the MnO promoter mainly prohibits the hydrogenation of C2H4 and C3H6, which is favorable to enhancing the selectivity to C2H4 and C3H6 and decreasing the formation of C2H6, and C3H8. It is also of interest that MnO has har 相似文献
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lntroductionInordcrtoselcctivcl}'produccIightoIcfinsfroms}'ngas.thcbinderusedforimprovingthecatal}'ststrcngthshouldbcfavorabIcforprimary'formingofligl1tolcfinsfroms}ngasandforprohibitingsidereactionsoflightoIcfi.sIll.lthasbccnshownthattheundesirablcstrengthofsilicalitc-2zcolitccanbcimprovcdb}addingbindcrs.Hot`ycver.thcadditionofthcbinder`"illcauscsomcchangcsinthcph}'sical-chcmicalstatcofthecatal}ticactivemetalas``cllasitscatal}ticbcha.io,ll'2I.InourprcviouspaperTiO2wasprovedtobcadcsirablcbi… 相似文献
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XU Long-Ya* WANG Qing-XiaLIANG Dong-Bai TIAN Zhi-JianYANG Li ZHAO Xiu-Shen WANG Kai-LiDalian Institute of Chemical Physics Academia Smica Dalian Ijiaaning 《天然气化学杂志》1995,(2)
High selectivity to light alkenes can be achieved from CO and CO_2hydrogenation over K-Fe-MnO/Si-2 catalyst.The alkene selectivity isinsensitive to reaction temperature for CO hydrogenation,while apparentlyincreases for CO_2 hydrogenation with raising reaction temperature.An increasein alkene selectivity is observed for both CO and CO_2 hydrogenation with GHSVrising,While a decrease with the elevation of reaction pressure for both CO/H_2and CO_2/H_2 reaction.A two-step mechanism is suggested forCO_2 hydrogenation to form hydrocarbons,by which the variations incontributions of CO and HC as products of CO_2/H_2 reaction with change ofreaction temperature,GHSV and pressure are explained.Moreover,thecatalyst is favorable for selective production of light olefins,which can alsoconcern the slightly secondary reactions of light olefins to some extent. 相似文献
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ThisprojectissllpportedbytheNationalNaturalScienceFotmdationofChina.IntroductionRecentstUdyonCOZhydrogenationfortheformationofhydrocarbonshascausedagreatinterest,especiallyintheproductionoflightalkenes.msreactionwillprovideanalternativeroutetoproducebasic… 相似文献
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K2O is a vital promoter to the Fe-MnO/silicalite-2 catalyst for light olefin formation from CO2 hydrogenation. With addition of it into the Fe-MnO/Si-2 catalyst the selectivity to light olefins increases greatly, while CH4 formation is inhibited evidently. Meanwhile, an obvious increment in CO2 conversion is also observed with the addition of K2O promoter. And it has been manifested that adding K2O to the Fe-MnO/Si-2 catalyst leads to remarkable increases in both the capacity and strength of the strong CO2 and CO adspecies. These produce much more[Cad] via their disproportionation at higher temperatures. This results in increase in the CO2 conversion and the selectivity to light olefins, and a decrease in CH4 formation. 相似文献
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EFFECTS OF BINDERS ON THE PRODUCTION OF LIGHT ALKENES FROM SYNGAS OVER K-Fe-MnO/SILICALITE-2 CATALYST I. EFFECT OF VARIOUS BINDERS ON CO HYDROGENATION 下载免费PDF全文
The performance of the K-Fe-MnO/Si-2 catalyst for the production of light olefins via Co hydrogenation changes obviously with the addition of binders. The results of CO hydrogenation. TPR, Mossbauer spectra CI0TPF, CO/H2-TPSR and C2H4/H2-TPSR are employed to investigate the effects of various binders on the physical-chemical states and catalytic behaviors of K-Fe-MnO/Si-2 catalyst to produce light olefins via syngas, TiO2 can promote the reduction of Fe and strengthen the adsorption of CO resulting in raising olefin selectivity. Other binders such as Al2O3, SiO2, MgO, once added into the catalyst, may cause formation of inorganic salts between FeO and Binders leading to a decrease of Fe reduction and a loss of olefin selectivity for CO hydrogenation. Especially, For K-Fe-MnO/Si-2 catalyst with Al2O3 binder directly, the strong secondary reactions of ethylene during CO hydrogenation cause a very poor light olefin selectivity, which will be improved greatly by modifying Al2O3. 相似文献
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PRODUCTION OF LIGHT OLEFINS FROM CO_2 HYDROGENATION OVER Fe/SILICALITE-2 CATALYST Ⅰ.CATALYTIC REACTIVI-FY AND REACTION MECHANISM 下载免费PDF全文
IntroductionRcccntl}'.researchinterestinhctcrogcllcotlscatal\'ticCOZh\'drogcnationhasfocusedontileproductionofh}'drocarbonsl1~-if.Asfortheformationoflightolefins.afo\'papershat'cbccllptlblishcdlit>l.Ho\\c\cr.tileprodllctionoflightolcfillsf'ronlCOZh}'droge… 相似文献