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The synthesis of syngas (H 2 : CO = 2) via catalytic partial oxidation of methane (CPOM) is studied over noble metal doped NiÀ CeO 2 bimetallic catalysts for CPOM reaction. The catalysts were synthesized via a controlled deposition approach and were characterized using XRD, BET-surface area analysis, H 2 -TPR, TEM, Raman and TGA analysis. The catalysts were experimentally and computationally studied for their activity, selectivity, and long-term stability. Although the pure 5Ni/CeO2 catalyst showed high initial activity (~90%) of CH 4 conversion, it rapidly deactivates around 20% of its initial activity within 140 hours of TOS. Doping of Ni/CeO 2 catalyst with noble metal was found to be coke resistant with the best-performing NiÀ Pt/CeO 2 catalyst showed ~95% methane conversion with > 90% selectivity at a temperature of 800 °C, having exceptional stability for about 300 hours of time-on-stream (TOS). DFT studies were performed to calculate the activation barrier for the CÀ H activation of methane over the Ni, Ni 3 Pt, Ni 3 Pd, and Ni 3 Ru (111) surfaces showed nearly equal activation energy over all the studied surfaces. DFT studies showed high coke formation tendency of the pure Ni (111) having a very small CÀ C coupling activation barrier (14.2 kJ/ mol). In contrast, the Ni 3 Pt, Ni 3 Pd, and Ni 3 Ru (111) surfaces show appreciably higher CÀ C coupling activation barrier (7 0 kJ/mol) and hence are more resistant against coke formation as observed in the experiments. The combined experimental and DFT study showed NiÀ Pt/CeO 2 as a promising CPOM catalyst for producing syngas with high conversion, selectivity and long-term stability suited for future industrial applications.

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In the present study, use of marble dust an inert filler produced by the marble cutting industries in the development of light weight block (LWB) of density 800 kg/m3 by non-auto clave method has been studied. Various mechanical and thermo-physical properties have been evaluated. It has been possible to replace cement by up to 20% when no additive is used. With the use of activator and super plasticizer at 50% replacement of cement by marble dust, compressive strength and water absorption are well within the Indian standard code 2185. With the use of accelerator and super plasticizer it is possible to reduce the de moulding time from 48 hrs to 6 hrs. Thermal conductivity of blocks varies from 1.16 to 2.30 [W/mK]. The variation in thermal conductivity depends upon its density which varies from 800 kg/m3 to 2400 kg/m3.