• G S Ramesh

      Articles written in Journal of Chemical Sciences

    • Design and fabrication of an automated thermal desorption gas-solid reaction system: Oxidation of ammonia and methanol over YBa2Cu3O7−δ(123) oxide systems

      M S Hegde S Ramesh G S Ramesh

      More Details Abstract Fulltext PDF

      A fully automated, versatile Temperature Programmed Desorption (TDP), Temperature Programmed Reaction (TPR) and Evolved Gas Analysis (EGA) system has been designed and fabricated. The system consists of a micro-reactor which can be evacuated to 10−6 torr and can be heated from 30 to 750°C at a rate of 5 to 30°C per minute. The gas evolved from the reactor is analysed by a quadrupole mass spectrometer (1–300 amu). Data on each of the mass scans and the temperature at a given time are acquired by a PC/AT system to generate thermograms. The functioning of the system is exemplified by the temperature programmed desorption (TPD) of oxygen from YBa2Cu3−xCoxO7 ± δ, catalytic ammonia oxidation to NO over YBa2Cu3O7−δ and anaerobic oxidation of methanol to CO2, CO and H2O over YBa2Cu3O7−δ (Y123) and PrBa2Cu3O7−δ (Pr123) systems.

    • Design and fabrication of an automated temperature programmed reaction system to evaluate 3-way catalysts Ce1−x−y,(La/Y)xPtyO2−δ

      Arup Gayen Tinku Baidya G S Ramesh R Srihari M S Hegde

      More Details Abstract Fulltext PDF

      A completely automated temperature-programmed reaction (TPR) system for carrying out gas-solid catalytic reactions under atmospheric flow conditions is fabricated to study CO and hydrocarbon oxidation, and NO reduction. The system consists of an all-stainless steel UHV system, quadrupole mass spectrometer SX200 (VG Scientific), a tubular furnace and micro-reactor, a temperature controller, a versatile gas handling system, and a data acquisition and analysis system. The performance of the system has been tested under standard experimental conditions for CO oxidation over well-characterized Ce1−−x−y Ptx(La/Y)yO2-δ catalysts. Testing of 3-way catalysis with CO, NO and C2H2 to convert to CO2, N2 and H2O is done with this catalyst which shows complete removal of pollutants below 325°C. Fixed oxide-ion defects in Pt substituted Ce1−y(La/Y)yO2−y/2 show higher catalytic activity than Pt ion-substituted CeO2.

  • Journal of Chemical Sciences | News

© 2021-2022 Indian Academy of Sciences, Bengaluru.