Catalytic Behavior of Supported KNiCa Catalyst and Mechanistic Consideration for Carbon Dioxide Reforming of Methane

Abstract Carbon dioxide reforming of methane to synthesis gas has been investigated using a KNiCa catalyst loaded on a highly siliceous NaZSM-5 zeolite support which was promoted with alumina. The catalytic behavior of the supported KNiCa catalyst has also been compared to that of the supported Ni catalyst. Long-time catalytic measurements at 800°C show that the supported KNiCa catalyst has excellent catalyst stability for 140 h due to the promotional effect of surface carbonate species leading to surface enrichment of carbon dioxide, while the supported Ni catalyst is subjected to severe catalyst deactivation due to extensive coke deposition less than 40 h on stream. Pulse reaction, thermogravimetric analysis, isotope experiment, and X-ray absorption spectroscopy have been performed for understanding the detailed chemistry and the mechanistic aspects of the CO 2 reforming. Pulse reaction and thermogravimetric analysis on the supported KNiCa catalyst indicate that methane is activated on the surface Ni species and carbon dioxide interacts with alkaline promoters to form surface carbonates which hinder the formation of inactive coke or scavenge carbon from the surface Ni species. A study of deuterium isotope effects for the reforming reaction shows that there is almost no isotope effect on the supported KNiCa catalyst, suggesting that a CH 4 dissociation step is not rate determining. In this work, mechanistic investgations reveal that reaction between the adsorbed carbon species and the dissociated oxygen atoms on Ni sites of catalyst surface leads to the production of carbon monoxide and the regeneration of metallic nickel species as a consequence, which is assumed to be a rate-determining step in the CO 2 reforming. It is also proposed that the oxidation step of surface carbon with surface oxygen or adsorbed CO 2 as surface carbonate species on the catalyst is important for maintaining catalyst stability of the supported KNiCa by the efficient removal of surface carbon species.

[1]  C. Au,et al.  Methane Dissociation and Syngas Formation on Ru, Os, Rh, Ir, Pd, Pt, Cu, Ag, and Au: A Theoretical Study , 1999 .

[2]  M. Bradford,et al.  CO2 Reforming of CH4 , 1999 .

[3]  T. Horiuchi,et al.  Isotope effect and rate-determining step of the CO2-Reforming of methane over supported Ni catalyst , 1998 .

[4]  A. C. van Veen,et al.  Kinetic study of the water–gas shift reaction and its role in the conversion of methane to syngas over a Pt/MgO catalyst , 1998 .

[5]  Seung-Bin Park,et al.  Investigation of Pt/γ-Al2O3Catalysts Prepared by Sol–Gel Method: XAFS and Ethane Hydrogenolysis , 1998 .

[6]  G. Millar,et al.  Characterisation of SiO2-supported nickel catalysts for carbon dioxide reforming of methane , 1998 .

[7]  Sang-Eon Park,et al.  CO2 behavior on supported KNiCa catalyst in the carbon dioxide reforming of methane , 1998 .

[8]  J. Lercher,et al.  Mono and bifunctional pathways of CO2/CH4 reforming over Pt and Rh based catalysts , 1998 .

[9]  X. Verykios,et al.  Specific Features Concerning the Mechanism of Methane Reforming by Carbon Dioxide over Ni/La2O3Catalyst , 1997 .

[10]  J. Bitter,et al.  The state of Zirconia Suported Platinum Catalysts for CO2/CH4 Reforming , 1997 .

[11]  E. Ruckenstein,et al.  Transient Response Analysis via a Broadened Pulse Combined with a Step Change or an Isotopic Pulse. Application to CO2 Reforming of Methane over NiO/SiO2 , 1997 .

[12]  R. T. Yang,et al.  Unified Mechanism of Alkali and Alkaline Earth Catalyzed Gasification Reactions of Carbon by CO2 and H2O , 1997 .

[13]  D. Acosta,et al.  Characterization of Alkali-Doped Ni/SiO2 Catalysts , 1997 .

[14]  Julian R.H. Ross,et al.  TAP Investigations of the CO2 Reforming of CH4 over Pt/ZrO2 , 1997 .

[15]  T. Horiuchi,et al.  CH4/CD4 isotope effect on the reaction of adsorbed hydrocarbon species in CO2-reforming over Ni/Al2O3 catalyst , 1997 .

[16]  L. M. Aparicio.  Transient Isotopic Studies and Microkinetic Modeling of Methane Reforming over Nickel Catalysts , 1997 .

[17]  C. Mirodatos,et al.  Methane Reforming Reaction with Carbon Dioxide over Ni/SiO2Catalyst: II. A Mechanistic Study , 1996 .

[18]  Zhaolong Zhang,et al.  Mechanistic aspects of carbon dioxide reforming of methane to synthesis gas over Ni catalysts , 1996 .

[19]  M. Bradford,et al.  Catalytic reforming of methane with carbon dioxide over nickel catalysts II. Reaction kinetics , 1996 .

[20]  M. Matsukata,et al.  A novel hydrogen/syngas production process : Catalytic activity and stability of Ni/SiO2 , 1996 .

[21]  C. Mirodatos,et al.  Methane reforming reaction with carbon dioxide over Ni/SiO2 Catalyst. I. Deactivation studies , 1996 .

[22]  W. Hally,et al.  The role of the oxidic support on the deactivation of Pt catalysts during the CO2 reforming of methane , 1996 .

[23]  C. Au,et al.  CH4/CD4 isotope effects in the carbon dioxide reforming of methane to syngas over SiO2-supported nickel catalysts , 1996 .

[24]  Tsunehiro Tanaka,et al.  Study on the Dispersion of Nickel Ions in the NiO−MgO System by X-ray Absorption Fine Structure , 1996 .

[25]  X. Verykios,et al.  Comparative Study of Carbon Dioxide Reforming of Methane to Synthesis Gas over Ni/La2O3 and Conventional Nickel-Based Catalysts , 1996 .

[26]  E. Ruckenstein,et al.  Pulse-MS study of the partial oxidation of methane over Ni/La2O3 catalyst , 1995 .

[27]  O. Krylov,et al.  Catalytic oxidation of hydrocarbons and alcohols by carbon dioxide on oxide catalysts , 1995 .

[28]  Jong‐Ho Kim,et al.  The reaction of CO2 with CH4 to synthesize H2 and CO over nickel-loaded Y-zeolites , 1994 .

[29]  K. Seshan,et al.  Carbon dioxide reforming of methane in the presence of nickel and platinum catalysts supported on ZrO2 , 1994 .

[30]  Sang-Eon Park,et al.  Catalytic reforming of methane with carbon dioxide over pentasil zeolite-supported nickel catalyst , 1994 .

[31]  J. R. Rostrup-Nielsen,et al.  Aspects of CO2-reforming of Methane , 1994 .

[32]  Jens R. Rostrup-Nielsen,et al.  CO2-Reforming of Methane over Transition Metals , 1993 .

[33]  Stern,et al.  Multiple-scattering x-ray-absorption fine-structure analysis and thermal expansion of alkali halides. , 1993, Physical review. B, Condensed matter.

[34]  E. Stern,et al.  Number of relevant independent points in x-ray-absorption fine-structure spectra. , 1993, Physical review. B, Condensed matter.

[35]  J. Rehr,et al.  Near-edge x-ray-absorption fine structure of Pb: A comparison of theory and experiment. , 1993, Physical review. B, Condensed matter.

[36]  L. Bonneviot,et al.  Nickel(II) ion-support interactions as a function of preparation method of silica-supported nickel materials , 1992 .

[37]  G. Somorjai,et al.  Catalytic low-temperature oxydehydrogenation of methane to higher hydrocarbons with very high selectivity at 8-12 % conversion , 1992 .

[38]  Y. Nishiyama,et al.  Role of MgO and CaO promoters in Ni-catalyzed hydrogenation reactions of CO and carbon , 1992 .

[39]  A. Lizzio,et al.  Transient kinetics study of catalytic char gasification in carbon dioxide , 1991 .

[40]  F. Solymosi.  The bonding, structure and reactions of CO2 adsorbed on clean and promoted metal surfaces , 1991 .

[41]  F. Solymosi,et al.  Catalytic reaction of CH4 with CO2 over alumina-supported Pt metals , 1991 .

[42]  J. Richardson,et al.  Carbon dioxide reforming of methane with supported rhodium , 1990 .

[43]  A. Gadalla,et al.  The role of catalyst support on the activity of nickel for reforming methane with CO2 , 1988 .

[44]  W. Mross.  Alkali Doping in Heterogeneous Catalysis , 1983 .

[45]  R. Baker,et al.  Catalysis: Science and Technology , 1982 .

[46]  C. P. Huang,et al.  Alkali promotion of nickel catalysts for carbon monoxide methanation , 1978 .