S. Thiemann-Handler

Publications (5)0 Total impact

• Article: Monolithic Electrochemically Promoted Reactors: A step for the practical utilization of Electrochemical Promotion

  S.P. Balomenou, D. Tsiplakides, A. Katsaounis, S. Brosda, A. Hammad, G. Foti, Ch. Comninellis, S. Thiemann-Handler, B. Cramer, C.G. Vayenas
  Solid State Ionics. 01/2006; 177:2199-2202.
• Chapter: Multilayer Ceramic Amperometric (MCA) NOx-Sensors Using Titration Principle

  B. Cramer, B. Schumann, H. Schichlein, S. Thiemann-Handler, T. Ochs
  [show abstract] [hide abstract]
  ABSTRACT: The removal of nitrogen oxides from exhaust emissions of combustion processes containing substantial levels of oxygen is a challenging venture, especially in lean burn spark ignition and diesel engines for automobiles, trains and ships, and coal/oil-fired power stations. We have developed multilayer ceramic amperometric (MCA) NOxsensors made of an oxygen ion conducting ceramic like yttrium stabilised zirconia using a new operation mode, the titration mode, which measures the consumption of hydrogen reducing NOx. The operation temperature is around 800°C which is controlled by an online impedance measurement. The integrated platinum heater is driven by a pulse width modulation. MCA NOx-sensors performed well under static and dynamic conditions. The titration mode was compared to a standard reduction mode where the nitrogen oxides are directly reduced electrochemically. Both operation modes show O2-cross sensitivity.
  12/2004: pages 311-319;
• Article: Novel monolithic electrochemically promoted catalytic reactor for environmentally important reactions

  S. Balomenou, D. Tsiplakides, A. Katsaounis, S. Thiemann-Handler, B. Cramer, G. Foti, Ch Comninellis, C. G. Vayenas
  [show abstract] [hide abstract]
  ABSTRACT: A novel dismantlable monolithic-type electrochem. promoted catalytic reactor and \"smart\" sensor-catalytic reactor unit has been constructed and tested for hydrocarbon oxidn. and NO redn. by C2H4 in presence of O2. In this novel reactor, thin (.apprx.20-40 nm) porous catalyst films made of two different materials are sputter-deposited on opposing surfaces of thin (0.25 mm) parallel solid electrolyte plates supported in the grooves of a ceramic monolithic holder and serve as sensor or electropromoted catalyst elements. Using Rh/YSZ/Pt-type catalyst elements, the 22-plate reactor operated with apparent Faradaic efficiency exceeding 25 achieving near complete fuel and NO conversion at 300 DegC in presence of up to 1.1% O2 in the feed at gas flow rates exceeding 1.3 l/min. The metal catalyst dispersion was of the order of at least 15%. The novel reactor design requires only two external elec. connections and permits easy practical utilization of the electrochem. promotion of catalysis. [on SciFinder (R)]
• Article: Novel monolithic electrochemically promoted catalytic reactor for environmentally important reactions

  S. Balomenou, D. Tsiplakides, A. Katsaounis, S. Thiemann-Handler, B. Cramer, G. Foti, Ch. Comninellis, C.G. Vayenas
  [show abstract] [hide abstract]
  ABSTRACT: A novel dismantlable monolithic-type electrochemically promoted catalytic reactor and “smart” sensor-catalytic reactor unit has been constructed and tested for hydrocarbon oxidation and NO reduction by C2H4 in presence of O2. In this novel reactor, thin (∼20–40 nm) porous catalyst films made of two different materials are sputter-deposited on opposing surfaces of thin (0.25 mm) parallel solid electrolyte plates supported in the grooves of a ceramic monolithic holder and serve as sensor or electropromoted catalyst elements. Using Rh/YSZ/Pt-type catalyst elements, the 22-plate reactor operated with apparent Faradaic efficiency exceeding 25 achieving near complete fuel and NO conversion at 300 °C in presence of up to 1.1% O2 in the feed at gas flow rates exceeding 1.3 l/min. The metal catalyst dispersion was of the order of at least 15%. The novel reactor design requires only two external electrical connections and permits easy practical utilization of the electrochemical promotion of catalysis.
  Applied Catalysis B: Environmental.
• Article: Monolithic electrochemically promoted reactors: A step for the practial utiliszation of electrochemical promotion

  S P Balomenou, D. Tsiplakides, A. Katsaounis, S. Brosda, A. Hammad, G. Foti, Ch Comninellis, S. Thiemann-Handler, B. Cramer, C. G. Vayenas