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Showing papers by "Preeti Aghalayam published in 2011"


Journal ArticleDOI
01 Mar 2011-Energy
TL;DR: In this article, the feasibility of in situ gasification of coal in a similar laboratory scale reactor set-up, under conditions relevant for field practice of underground coal gasification, using an oxygen-steam mixture as the feed gas.

66 citations


Journal ArticleDOI
TL;DR: In this paper, the authors compared the performance of a single step reaction and a multiple reaction model for predicting hydrogen-oxygen reaction over a platinum surface and found that the diffusion controlled model over-predict the data.

35 citations


Journal ArticleDOI
TL;DR: In this paper, the authors simplify the modeling approach for relatively quick but reliable predictions for application in process design and optimization, and the primary objective of this work is to simplify the modelling approach for a relatively quick and reliable prediction.
Abstract: During underground coal gasification (UCG), a cavity is formed in the coal seam when coal is converted to gaseous products This cavity grows three dimensionally in a nonlinear fashion as gasification proceeds The cavity shape is determined by the flow field, which is a strong function of various parameters such as the position and orientation of the inlet nozzle and the temperature distribution and coal properties such as thermal conductivity In addition to the complex flow patterns in the UCG cavity, several phenomena occur simultaneously They include chemical reactions (both homogeneous and heterogeneous), water influx, thermomechanical failure of the coal, heat and mass transfer, and so on Thus, enormous computational efforts are required to simulate the performance of UCG through a mathematical model It is therefore necessary to simplify the modeling approach for relatively quick but reliable predictions for application in process design and optimization The primary objective of this work is to

33 citations


Journal ArticleDOI
TL;DR: In this paper, the effect of Si/Pd molar ratio, particle size and reusability with respect to reactor temperature on the catalytic activity of PdMCM-41 catalyst was examined.
Abstract: Palladium supported MCM-41 molecular sieves with Si/Pd (molar) ratios of 400, 200, 100 and 50 were synthesized by hydrothermal method. All catalysts characterized by various analytical and spectroscopic techniques, viz, XRD, N2 sorption, TEM, DRUV-VIS, Raman. XRD at low angle and high angle studies suggest that the substitution of palladium and presence of palladium oxide phase in the silicate tetrahedral framework structure of MCM-41. TEM investigations confirm the highly ordered cubic structure with irregular distribution of palladium nanoparticles on surface PdMCM-41. DRUV-VIS and Raman spectra studies indicate the presence of palladium oxide moieties in all PdMCM-41 catalysts. The effect of Si/Pd molar ratio, particle size and reusability with respect to reactor temperature on the catalytic activity of PdMCM-41 catalyst was examined. Comparative study of all these palladium substituted catalysts shows that PdMCM-41(50) catalyst having higher palladium contents shows higher activity at lower temperatures as compared with other PdMCM-41(Si/Pd = 100, 200, 400) catalysts.