ﭘﺎ ﻣﻘﺎﻻت ﻣﺠﻤﻮﻋﻪ اﻳﺮان ﺷﻨﺎﺳﯽ ﮐﺎﻧﯽ و ﺑﻠﻮرﺷﻨﺎﺳﯽ اﻧﺠﻤﻦ هﻤﺎﻳﺶ ﻧﺰدهﻤﻴﻦ- ﻣﺸﻬﺪ ﻓﺮدوﺳﯽ داﻧﺸﮕﺎﻩ۵٩ Characterization of mixed crystalline cobalt manganese catalysts by XRD, SEM, TGA, DSC and BJH methods Ali Akbar Mirzaei 1 , Mostafa Feyzi 1* , Flora Shayegh 2 Hamid Reza Bozorgzadeh 2 , and Adel 1 Bigbabaei 1 Department of Chemistry, Faculty of Sciences, Sistan & Baluchestan University, P.O. Box 98135-674, Zahedan, Iran. Tel: +98 (541) 2428247, Fax: +98 (541) 2446565. 2 Research Institute of Petroleum Industry (RIPI) Gas Division, Tehran, Iran. Mixed crystalline cobalt manganese oxides were prepared using co-precipitation procedure and studied for the conversion of CO/H 2 to light olefins. In particular, the effect of a range of preparation variables such as [Co]/[Mn] molar ratios of the precipitation solution, precipitate aging time, were investigated in detail. The results are interpreted in terms of the structure of the active crystalline catalyst and it has been generally concluded that the catalyst containing [Co]/[Mn]=1/6 molar basis and aged for 30min the is optimum catalyst. Characterization crystalline catalysts by powder X-ray diffraction, scanning electron microscopy (SEM), BET specific surface area and thermal analysis methods such as TGA and DSC showed that all the molar ratios of and [Co]/[Mn]=1/6 and aging time influenced the crystalline structure and morphology. Keywords Co-precipitation, crystalline, Characterization, cobalt manganese oxides ﭼﮑ ﻴ ﺪﻩ: ا در ﻳ ﺗﺤﻘ ﻦѧ ﻴ ﮐﺎﺗﺎﻟﺪاѧ اﺑﺘ ﻖ ﻴﺎѧ ﺰوره ﯼﺴѧ اﮐﻮطѧ ﻣﺨﻠ ﻴ ﺪ ﯼﺎѧ ﺑﻠﻮره ﯼﻦѧ ﺁه- ﻧ ﻴﻮﺑѧ هﻤﺮﺳ روشﻪѧ ﺑﻞѧ ﮑ ﯽﻪѧ ﺑ وﺪﻩѧ ﺷﺎﺧﺘﻪѧ ﺳ ﺪѧ ﺗﺒ ﻣﻨﻈﻮر ﻳѧ اوﻟﻔﻪѧ ﺑﻨﺘﺰѧ ﺳﺎزѧ ﮔ ﻞ ﻴﺎѧ ه ﻦ ﯼ ﻧﻈﺒﮏѧ ﺳѧ ﻴѧ اﺗ ﺮ ﻴﺮوﭘѧ ﭘ ﻠﻦ، ﻴﻮﺗѧ ﺑ و ﻠﻦ ﻴﺪѧ ﮔﺮﻓﺘﻨﺮارѧ ﻗﻪѧ ﻣﻄﺎﻟﻌﻮردѧ ﻣ ﻠﻦ. ﺮѧ اﺛ ﺮاѧ ﺷ ﻳ ﺗﻬ ﻂѧ ﻴﻮﻟѧ ﻣﺴﺒﺖѧ ﻧﺪѧ ﻣﺎﻧﻨﻮرѧ ﺑﻠ ﻪ ﯽ[Co]/[Mn] و ﻋﻤﺮد ﺎنѧ زﻣﺪتѧ ﻣѧ ه ﯽﻮرѧ ﺑﻠﻮﺑﺎتѧ رﺳﻪѧ ﺑ ﻳﺮدѧ ﻋﻤﻠﮑﺮѧ ﺑ ﻦ ﮐﺎﺗﺎﻟ ﻴ ﺰور ﯼ ه در ﺁﻧﻬﺎ ﻴ ﺪروژﻧﺎﺳ ﻴ ﻣﻮﻧﻮﮐﺴ ﮐﺮﺑﻦ ﻮن ﻴѧ ﺑﺮرﺳ ﻣﻮرد ﺪﺖѧ ﮔﺮﻓﺮارѧ ﻗ ﯽ. ﺑﺮﺎѧ ﻧﺘﺎسѧ اﺳ ﻳﺪﻩѧ ﺁﻣﺖѧ دﺳﻪѧ ﺑ ﺞ ﮐﺎﺗﺎﻟ ﺑﻠﻮر ﻴ ﺰور ﯼ ﻣﻮﻟ ﻧﺴﺒﺖ ﺑﺎ ﯽ[Co]/[Mn]=1/6 ﻣﺪت ﺑﻪ ﮐﻪ ﻧﻴﻢ ﻋﻤﺮده ﺳﺎﻋﺖ ﯽﺎﻟѧ ﮐﺎﺗﻮانѧ ﻋﻨﻪѧ ﺑ ﺷﺪﻩ ﻴ ﺰور ﺑﻬ ﻴ ﮔﺮد اﻧﺘﺨﺎب ﻨﻪ ﻳ ﺪ. ﻣﺸﺨﺼﺎت ﺑﻠﻮره ﺗﻤﺎم ﺎ ﯼ ﮐﺎﺗﺎﻟ ﻴ ﺴﺘﻬﺎ ﯼ ﺗﻬ ﻴ ﺗﮑﻨ ﮐﻤﮏ ﺑﻪ ﺷﺪﻩ ﻪ ﻴ ﮑﻬﺎ ﯼﺘﮕﺎهѧ دﺳ ﯽ ﻧﻈѧ ﻴﺮاشѧ ﭘ ﺮ ﭘﺮﺗﻮهﺎ ﯼ ا ﻳ ﮑﺲ) XRD ( ﻣ، ﻴ اﻟﮑﺘﺮوﻧ ﮑﺮوﺳﮑﻮپ ﯽ) (SEM), ، ﺁﻧﻠ ﻴ ﺣﺮارﺗ ﺰ ﯽ ﻧﻈѧ ﻴ ﺮTGA وDSC ﺪازﻩѧ اﻧ و ﮔ ﻴ ﺮ ﻳ ﻬﺎ ﯼﻄﺢѧ ﺳﺪѧ ﻣﺎﻧﻨBET ﺗﻌﻴѧ ﻴﺖѧ اﺳﺪﻩѧ ﺷ ﻦﯽѧ ﻣﺸﺎنѧ ﻧﻪѧ ﮐ درﻮﺛﺮѧ ﻣﯽѧ دهﻮبѧ رﺳﺎنѧ زﻣ وﻮﻟﯽѧ ﻣﺴﺒﺖѧ ﻧﺪѧ دهﻨ ﺑﻠﻮ ﻣﻮرﻓﻮﻟﻮزﯼ و ﺳﺎﺧﺘﻤﺎن هﺴﺘﻨﺪ ر. ﮐﻠﻴﺪﯼ واژﮔﺎن: هﻤﺮﺳﻮﺑﯽ، ﺑﻠﻮرﻳﻦ، ﺳﺎﭘﻮرت ﻣﺸﺨﺼﺎت،، اﮐﺴﻴﺪﮐﺒﺎﻟﺖ- ﻣﻨﮕﻨﺰ Introduction: Fischer–Tropsch synthesis is of great industrial importance due to the great variety of products obtained such as paraffins, olefins and alcohols. Fe–Mn, Fe-Co and Co–Mn catalysts favors C 2 –C 4 olefins [1,4]. High C 2 –C 4 selectivity for the iron-rich Fe–Mn solid has been correlated with the (Fe1- xMnx) 3 O 4 spinel phase and two carbide phases, while the manganese-rich solid has been correlated with two spinel phases and different carbide phases [5]. The Co–Mn catalysts are mainly composed of metallic cobalt particles dispersed in MnO [6], but Fe–Co catalyst favour intermetallic alloy formation [7-10]. In this work, a series of iron nickel molar with different molar ratios are analyzed by XRD, SEM, TGA, DSC and BET methods to elucidate the solid phases possibly involved in the high catalytic activity and C 2 –C 4 olefin selectivity.