http://nopr.niscair.res.in/handle/123456789/9006 Search the Channel search http://nopr.niscair.res.in/simple-search http://nopr.niscair.res.in/handle/123456789/9520 Title: CO oxidation over Pd/<img src='/image/spc_char/gamma.gif' border=0>-FeMnO₃ catalyst <br/> <br/>Authors: Kulshreshtha, S K; Sharma, S; Vijayalakshmi, R; Sasikala, R <br/> <br/>Abstract: <img src='/image/spc_char/gamma.gif' border=0>-FeMnO₃ samples with and without Pd metal impregnation have been prepared by co-precipitation method and investigated by powder X-ray diffraction and ⁵⁷Fe Mossbauer spectroscopy techniques, for its bulk characteristics. Catalytic activity of these samples has been studied for CO oxidation reaction by injecting CO or (CO+O₂) pulses over their surface, with a view to delineate the role of Pd metal and reducible cations during this reaction. Pd metal impregnation over the surface of <img src='/image/spc_char/gamma.gif' border=0>-FeMnO₃, leads to significant improvement in its catalytic activity, particularly at lower temperatures. Based on these experiments, clear evidence for the low temperature (T~350 K) disproportionation of CO over the surface of Pd metal particles and lattice oxygen incorporation during CO oxidation reaction, have been presented. From the comparative study of Fe₂O₃, Mn₂O₃ and FeMnO₃, the existence of any synergistic effects between Fe³⁺ and Mn³⁺ cations, is ruled out for FeMnO₃, mixed oxide system. <br/> <br/>Page(s): 427-433 http://nopr.niscair.res.in/handle/123456789/9519 Title: Low temperature oxidation of ethanol <br/> <br/>Authors: Verma, S S <br/> <br/>Abstract: Oxidation characteristics of ethanol in the temperature range 200 to 1000 ^oC suitable to its use in automobiles are studied to highlight the role and optimum values of different combustion controlling parameters for its clean combustion. Sensitivity evaluation of different reaction paths has concluded some important reactions responsible for the ethanol oxidation. It is observed that clean combustion of ethanol can be obtained with a proper combination of combustion parameters <i>viz.</i>, temperature, C₂H₅OH/O₂ mole ratio and residence time <br/> <br/>Page(s): 410-422 http://nopr.niscair.res.in/handle/123456789/9518 Title: Vapour phase transesterification over solid acids for the synthesis of isoamyl salicylate <br/> <br/>Authors: Souza, Joyce D; Nagaraju, N <br/> <br/>Abstract: The transesterification of methyl salicylate with isoamyl alcohol has been studied in vapour phase over solid acid catalysts for the synthesis of isoamyl salicylate. The catalysts used include simple oxides — Al₂O₃, SiO₂, ZrO₂ and mixed oxides ZrO₂-Al₂O₃ and ZrO₂-SiO₂. The effect of sulphation on the catalytic activity of the oxides and mixed oxides has also been investigated for this reaction. Catalytic activity studies have been conducted at 200^oC for two different flow rates, 5 and 10 mL/h to check the effect of the contact time of the reactants with the catalyst. All the catalysts used in the reaction have been found to be active for the formation of isoamyl salicylate via transesterification of methyl salicylate with isoamyl alcohol. SO₄²/ZrO₂-SiO₂ (2:8) has been found to be the most active catalyst with 63% conversion of methyl salicylate to isoamyl salicylate. SO₄^2-/ZrO₂, which exhibited good selectivity was chosen as the catalyst for optimisation of the reaction conditions to obtain better yield and higher selectivity of isoamyl salicylate. Optimum yield of isoamyl salicylate was obtained with the following reaction conditions: amount of catalyst = 0.5 g, calcination temperature = 550^oC, reaction temperature = 200 ^oC, preheater temperature = 250 ^oC, molar ratio of methyl salicylate to isoamyl alcohol = 1:1. <br/> <br/>Page(s): 401-409 http://nopr.niscair.res.in/handle/123456789/9517 Title: Inhibition of mild steel corrosion in formic and acetic acid solutions <br/> <br/>Authors: Quraishi, M A; Sharma, H K <br/> <br/>Abstract: Four organic inhibitors namely, 4-amino-3-methyl-5-mercapto-1,2,4-triazole (AMMT), 4-amino-3-ethyl-5-mercapto-1,2,4-triazole (AEMT), 4-amino-3-propyl-5-mercapto-1,2,4-triazole (APMT) and 4-amino-3-butyl-5-mercapto-1,2,4-triazole (ABMT) were synthesized to investigate their inhibiting actions on corrosion of mild steel (MS) in aqueous solutions containing 20% formic acid and 20% acetic acid by weight loss and potentiodynamic polarization methods. All of these compounds have shown good inhibition efficiency (<i>IE</i>) in the formic acid and acetic acid solutions. <i>IE </i>of these compounds has been found to vary with the concentration of the compounds, temperature, immersion time and concentration of acid solutions. The adsorption of these compounds on the mild steel surface from both the acids has been found to obey Langmuir adsorption isotherm. The values of activation energy (<i>E</i>_a) and free energy of adsorption (<img src='/image/spc_char/delta.gif' border=0><i>G</i>_ads) indicated physical adsorption of these compounds on the steel surface. The potentiodynamic polarization experiments revealed that all the compounds are mixed type inhibitors. <br/> <br/>Page(s): 331-336