01931nas a2200169 4500008004100000022001400041245007500055210006900130260007100199300001400270490000700284520129100291100002601582700002401608700002601632856010301658 2006 eng d a0887-062400aOxy-CO2 reforming of methane to syngas over CoOx/CeO2/SA-5205 catalyst0 aOxyCO2 reforming of methane to syngas over CoOxCeO2SA5205 cataly a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcSEP a1753-17560 v203 a

The oxy-CO2 methane reforming (OCRM) process has been investigated over the CoOx/CeO2/SA-5205 catalyst at varying reaction temperatures (750-900 degrees C), O-2/CH4 ratios (0.3- 0.45), and space velocities (20 000 - 100 000 cm(3)/g/h). With an increasing OCRM reaction temperature, the contribution from the CO2 methane reforming reaction increased while that from methane combustion reactions decreased. Correspondingly, there was an increase in the H-2/CO ratio and a sharp decrease in reaction exothermicity. At 900 C (gas hourly space velocity = 46 000 cm(3)/g/h and O-2/CH4 = 0.4), the OCRM reaction over the CoOx/CeO2/SA-5205 catalyst was mildly endothermic with > 90% CH4 conversion, > 95% H-2 selectivity, and a H-2/CO ratio of 1.63. CH4 conversion was relatively unaffected by the O-2/CH4 ratio used in the OCRM reaction; however, CO2 conversion decreased on increasing the O-2/CH4 ratio. While H-2 selectivity was not significantly affected by the O-2/CH4 ratio, the H-2/CO ratio increased linearly with an increasing O-2/CH4 ratio. The endothermicity of the reaction was found to decrease with an increasing CH4/O-2 ratio, which can be explained on the basis of increased contribution from the methane partial oxidation reaction with an increasing O-2/CH4 ratio.

1 aChoudhary, Vasant, R.1 aMondal, Kartick, C.1 aChoudhary, Tushar, V. uhttp://library.ncl.res.in/content/oxy-co2-reforming-methane-syngas-over-cooxceo2sa-5205-catalyst-002231nas a2200205 4500008004100000022001400041245007400055210006900129260009900198300001400297490000700311520148400318653001201802653002201814653001101836100002601847700002401873700002601897856010201923 2006 eng d a0016-236100aOxy-CO2 reforming of methane to syngas over CoOx/MgO/SA-5205 catalyst0 aOxyCO2 reforming of methane to syngas over CoOxMgOSA5205 catalys aTHE BOULEVARD, LANGFORD LANE, KIDLINGTON, OXFORD OX5 1GB, OXON, ENGLANDbELSEVIER SCI LTDcDEC a2484-24880 v853 a

The OXY-CO2 methane reforming reaction (OCRM) has been investigated over CoOx supported on a MgO precoated highly macroporous silica-alumina catalyst carrier (SA-5205) at different reaction temperatures (700-900 degrees C), O-2/CH4 ratios (0.3-0.45) and space velocites (20,000-100,000cc/g/h). The reaction temperature had a profound influence on the OCRM performance over the CoO/MgO/SA-5205 catalyst; the methane conversion, CO2 conversion and H-2 selectivity increased while the H-2/CO ratio decreased markedly with increasing reaction temperature. While the O-2/CH4 ratio did not strongly affect the CH4 and CO2 conversion and H-2 selectivity, it had an intense influence on the H-2/CO ratio. The CH4 and CO2 conversion and the H-2 selectivity decreased while the H-2/CO increased with increasing space velocity. The O-2/CH4 ratio and the reaction temperature could be used to manipulate the heat of the reaction for the OCRM process. Depending on the O-2/CH4 ratio and temperature the OCRM process could be operated in a mildly exothermic, thermal neutral or mildly endothermic mode. The OCRM reaction became almost thermoneutral at an OCRM reaction temperature of 850 degrees C, O-2/CH4 ratio of 0.45 and space velocity of 46,000 cc/g/h. The CH4 conversion and H-2 selectivity over the CoO/MgO/SA-5205 catalyst corresponding to thermoneutral conditions were excellent: 95% and 97%, respectively with a H-2/CO ratio of 1.8. (c) 2006 Elsevier Ltd. All rights reserved.

10amethane10aoxy-CO2 reforming10aSyngas1 aChoudhary, Vasant, R.1 aMondal, Kartick, C.1 aChoudhary, Tushar, V. uhttp://library.ncl.res.in/content/oxy-co2-reforming-methane-syngas-over-cooxmgosa-5205-catalyst-002179nas a2200241 4500008004100000022001400041245016900055210006900224260007300293300001200366490000600378520124700384653001701631653002801648653001201676653002201688653001701710653001101727100002601738700002401764700002601788856012301814 2007 eng d a1566-736700aOxy-methane reforming over high temperature stable NiCoMgCeOx and NiCoMgOx supported on zirconia-haffnia catalysts: accelerated sulfur deactivation and regeneration0 aOxymethane reforming over high temperature stable NiCoMgCeOx and aPO BOX 211, 1000 AE AMSTERDAM, NETHERLANDSbELSEVIER SCIENCE BVcMAR a561-5640 v83 a

NiCoMgOx and NiCoMgCeOx on commercial low surface area zirconia-haffnia catalysts have unusually high thermal stability (>= 2000 degrees C) for syngas generation via the methane partial oxidation process (J. Catal., 233, 36, 2005). Herein we report the results on accelerated sulfur deactivation (0.74 mol% sulfur in feed) and corresponding regeneration (at 800 degrees C in 1:1 O-2 + N-2 flow) over these catalysts. The NiCoMgCeOx catalyst, due to a larger mobility of lattice oxygen, showed a considerably higher resistance to sulfur poisoning; the higher mobility of the lattice oxygen in case of the NiCoMgCeOx catalyst may be related to the presence of CeO2. During the deactivation process, the selectivity for H-2 was decreased to a much greater extent than that for CO. Regeneration studies showed that even after complete deactivation of the catalysts, the original activity/selectivity of both the catalysts could be completely restored after a simple regeneration process. Based on their exceptionally high thermal stability, high activity/selectivity and easily regenerability, the NiCoMOx, and NiCoMgCeOx catalysts appear to be very promising candidates for the CPOM process. (c) 2006 Elsevier B.V. All rights reserved.

10aDeactivation10ahigh temperature stable10amethane10aPartial oxidation10aRegeneration10aSulfur1 aChoudhary, Vasant, R.1 aMondal, Kartick, C.1 aChoudhary, Tushar, V. uhttp://library.ncl.res.in/content/oxy-methane-reforming-over-high-temperature-stable-nicomgceox-and-nicomgox-supported