02322nas a2200313   4500008004100000022001400041245010700055210006900162260011000231300001400341490000700355520118000362653002901542653001401571653002301585653002001608653001801628653002201646653001601668653002801684653003001712653002301742653001101765100002301776700001801799700002701817700003301844856013101877       2012                        eng d  a0376-471000aCarbon dioxide reforming of methane over ruthenium substituted strontium titanate perovskite catalysts0 aCarbon dioxide reforming of methane over ruthenium substituted s  aDR K S KRISHNAN MARG, PUSA CAMPUS, NEW DELHI 110 012, INDIAbNATL INST SCIENCE COMMUNICATION-NISCAIRcSEP  a1339-13470 v513 a<p>Strontium titanate (SrTiO3) doped with varying amounts of ruthenium (7.9, 15.6 and 31 wt%) have been prepared by the citrate gel synthesis method. Structural and textural characterizations reveal that at lower concentrations, a major part of Ru is incorporated in the lattice of SiTiO3. The content of surface Ru (outside lattice) increases with increasing amounts of the doped Ru. The surface Ru reduced at lower temperatures compared to Ru incorporated into the lattice. The reduction of the lattice substituted Ru occurs only at temperatures above the collapse of the perovskite structure. The catalyst sample with 7.9 wt% of Ru shows good conversions in the dry reforming of methane with CO2. The conversion of CO2 is in excess compared to methane under the studied reaction conditions. As a result, H-2/CO ratio of the product gases which should have been equivalent to unity is lower than the stoichiometric value. This ratio is particularly low when lower reaction temperatures (873-973 K) were used. Similar was the case when high space velocities were used. Low methane conversion and reverse water gas shift reaction are the causes for the low H-2/CO ratios.</p>10aCarbon dioxide reforming10aCatalysts10aCitrate gel method10aDoped catalysts10aDry reforming10aMethane reforming10aPerovskites10aReverse water gas shift10aRuthenium doped catalysts10aStrontium titanate10aSyngas1 aGurav, Hanmant, R.1 aBobade, Richa1 aDas, Vineetha, Lakshmi1 aChilukuri, Satyanarayana, V.  uhttps://library.ncl.res.in/content/carbon-dioxide-reforming-methane-over-ruthenium-substituted-strontium-titanate-perovskite-002611nas a2200181   4500008004100000245010600041210006900147260000800216300001200224490000800236520194800244100001902192700002202211700001802233700002302251700002902274856012602303       2018                        eng d00aActive and durable alkaline earth metal substituted perovskite catalysts for dry reforming of methane0 aActive and durable alkaline earth metal substituted perovskite c  cMAY  a146-1580 v2243 aDry reforming of methane is an important process for the utilization of CO2 and to get valuable synthesis gas. Alkaline earth metal substituted MZr1-xNixO3-delta perovskites were synthesized by citrate gel method, characterized and evaluated for dry reforming methane. Characterization results show that the type of alkaline earth substituted at the A site of the perovskite oxide plays an important role in terms of structure, basicity, oxygen deficiency and Ni dispersion. Calcium substituted CaZr0.8Ni0.2O3-delta catalyst shows superior activity in terms of high CH4 and CO2 conversion, while maintaining the activity even after 500 h of reaction. Mechanistic investigations were carried out using transient pulse experiments and insitu FTIR-diffuse reflectance spectroscopy. These experiments reveal that redox property and basicity play important role in activation and sustaining the reforming reaction. Insitu FTIR measurements show that surface hydroxyl groups of the support are vital for high activity and durability of CaZr0.8Ni0.2O3-delta catalyst. XRD and TGA analysis of catalysts after reaction show the structures are retained, but peaks pertaining to coke were observed on SrZr0.8Ni0.2O3-delta and BaZr0.8Ni0.2O3-delta catalysts. On the otherhand, CaZr0.8Ni0.2O3-delta catalyst had only amorphous carbon even after 500 h of reaction. HRTEM studies revealed that SrZr0.8Ni0.2O3-delta and BaZr0.8Ni0.2O3-delta catalysts deactivated mostly due to the formation of carbon nanotubes with Ni embedded in them. Raman and XPS analysis helped in identifying types of coke precursors present on the catalysts. The investigation also illustrate that type of carbon formed depends on the basicity of perovskite oxide, metal to support interaction, Ni crystallite size, surface hydroxyl groups and oxygen defects. This study clearly demonstrated that CaZr0.8Ni0.2O3-delta is an excellent catalyst for dry reforming reaction with long life.1 aDama, Srikanth1 aGhodke, Seema, R.1 aBobade, Richa1 aGurav, Hanmant, R.1 aChilukuri, Satyanarayana  uhttps://library.ncl.res.in/content/active-and-durable-alkaline-earth-metal-substituted-perovskite-catalysts-dry-reforming02139nas a2200241   4500008004100000022001100041245012700052210007100179260000900250300001000259490000800269520128500277653001801562653001701580653003901597653002001636100001901656700001801675700001801693700001901711700003301730856013401763       2018                        eng d  a21951700aTuning the dimensionality of layered Srn+1Tin−xNixO3n+1 perovskite structures for improved activity in syngas generation0 aTuning the dimensionality of layered Srn1Tin−xNixO3n1 perovskite  cAPR   a27-390 v3603 a<p>Interest in perovskite type oxides is growing due to their versatile catalytic applications. A series of Ruddlesden-Popper (RP) type layered perovskite oxides Srn+1Tin−xNixO3n+1 were prepared and evaluated for their catalytic activity in steam reforming, CO2 reforming and bi-reforming of methane. These materials, prepared through citrate gel method were characterized to understand their structure and Ni reducibility. Substitution of Ni in RP phases was established through refinement of XRD powder pattern. During methane reforming, the catalytic activity increased with the order of RP phase of SrTi1−xNixO3−δ (n = ∞). TPR results show variation in Ni reducibility with the order of RP phase, while TPD-O2 study helped to estimate oxygen vacancies. These vacancies seem to influence catalytic activity during methane reforming. Transient pulse experiments show that CO2 dissociates over oxygen vacancies to give CO and oxygen, with later replenishing lattice oxygen in SrTi0.8Ni0.2O3−δ (n = ∞) phases. Highly labile oxygen vacancies generated in the bulk of SrTi0.8Ni0.2O3−δ must be migrating to the surface, helping in the removal of coke formed. Characterization of catalysts after reaction helped in better understanding of coke precursors.</p>10aDry reforming10aNickelSyngas10aRuddlesden-Popper (RP) perovskites10aSteam reforming1 aDama, Srikanth1 aGhodke, Seema1 aBobade, Richa1 aGurav, Hanmant1 aChilukuri, Satyanarayana, V.  uhttps://library.ncl.res.in/content/tuning-dimensionality-layered-srn1tin%E2%88%92xnixo3n1-perovskite-structures-improved-activity