Papers by Keyword: Water Gas Shift Reaction

Abstract: Montmorillonite pillared by mixing Fe, Fe-Cr, Al-Fe and Cu-Al complexes was investigated for their catalytic activities for Water Gas Shift Reaction (WGSR). Element chemical analysis showed that the content of Fe, Fe-Cr, Al-Fe catalysts were 26.93%, 31.03%, 28.20%, respectively. Compared with the traditional shift catalyst, in the same shift condition, we can use the PILC catalysts to substitute. Using PILC catalysts can accurately control the constitution of synthesis gas over changing shift rate.

Abstract: This paper reports the effect of alkali precipitating agents, i.e. KOH and NaOH, on activity and stability of Cu-Mn based catalysts for the water gas shift (WGS) reaction. Structural and texture characteristics of the catalysts were characterized by low temperature N2 adsorption, X-Ray Diffraction (XRD) and TPR techniques. The XRD and low temperature N2 adsorption results showed the two types of precipitators produced different Cu-Mn phases during precipitation and drying. The KOH precipitator resulted in partial precipitation of copper ion and formation of hydrate basic copper sulfate, Cu₄SO₄(OH)₆•H₂O after drying; while the NaOH precipitator led to a completed precipitation of Cu ion and formation of relatively stable Cu₂₊₁O and Mn₃O₄ crystals after drying. These phases formed after precipitation by the KOH and NaOH, however, experienced the same phase change during calcination and activation, namely, they first changed to Cu_1.5Mn_1.5O₄ in calcination followed by the formation of microcrystalline Cu and MnO phases during activation. The Cu-Mn WGS catalysts prepared by the NaOH was found to have larger surface area and more content of Cu and MnO phases after activation, which might be the reasons of higher activity and better stability of the Cu-Mn catalyst.

Abstract: The effects of Cu/Mn ratio on the activity and stability of Cu-Mn catalysts for the water-gas shift reaction (WGSR) were investigated. Activity tests showed that the Cu-Mn catalyst while the ration of Cu to Mn is 1:1 displayed higher activity and better stability than that of others catalysts. The BET , XRD and TPR results revealed that the Cu-Mn catalyst while the ration of Cu to Mn is 1:1 led to higher surface area, a more stable catalyst structure and suitable reduction performance, in turn leading to better catalytic behavior for the Cu-Mn catalyst.

Abstract: The effects of alkali charge on the activity and stability of copper-based mixed oxides catalyst for the water-gas shift reaction (WGSR) were investigated. Activity tests showed that the copper-based mixed oxides catalyst while the 2[NaOH]/[Cu²⁺+Mn²⁺] is above 1.2 displayed higher activity and better stability than that of others catalysts. The BET , XRD and TPR results revealed that the Cu-Mn catalyst while the 2[NaOH]/[Cu²⁺+Mn²⁺] is above 1.2 led to higher surface area, a more stable catalyst structure and suitable reduction performance, in turn leading to better catalytic behavior for the Cu-Mn catalyst.

Abstract: This paper aims to synthesize and characterize nanosized nickel and zinc ferrites (NiFe₂O₄ and ZnFe₂O₄) samples by a combustion reaction method, using glycine as fuel. The performance in HT-WGRS reaction the samples was investigated. The results showed that the combustion reaction was effective in the production of major phases of the spinel ferrite (crystallite sizes of 44 and 27 nm) and presence of the secondary phases, such as Ni and ZnO, with surface area 3 and 115 m²/g for NiFe₂O₄ and ZnFe₂O₄, respectively. HT-WGSR activity was achieved (80%) to NiFe₂O₄ ferrite in the temperature range of 300 - 500°C.

Abstract: Water-gas shift reaction is an important industrial reaction, used for producing synthesis gas and ammonia as well as pure hydrogen for supplying at PEM fuel cells. In this work, an overview on water gas shift reaction performed in Pd-based membrane reactors is shown, paying particular attention to the influence on the performances of some operating variables such as reaction temperature, reaction pressure, H2O/CO molar ratio and sweep gas.