Tailor-structured skeletal Pt catalysts employed in a monolithic electropromoted reactor

Abstract

The performance of a monolithic electropromoted reactor was investigated under high gas flow rates, for the oxidation of ethylene utilizing thin (40 nm) tailorstructured highly porous skeletal Pt catalyst-electrodes coated on Y 2 O 3 -stabilized-ZrO 2 (YSZ). Electrochemical enhancement was observed at gas flow rates as high as 25 L min -1 and mean gas residence times as low as 0.15 s. This is a promising step for the practical utilization of the electrochemical promotion of catalysis. An interesting feature of the skeletal Pt catalyst-electrodes is the appearance of a sharp rate maximum upon anodic current interruption which appears to be related to their dendritic structure and enhanced capacity for promoter storage.

Ionically Conducting Ceramics as Active Catalyst Supports

“…Moreover, the MEPR was successfully operated and EPOC of ethylene oxidation was induced on active skeletal-Pt-catalysts at flow rates as high as 56 L min –1 (Λ = 30), mean gas residence times of 0.34 s, and reactor space velocities up to 2.7 × 10 4 h –1 , showing the strong potential of this reactor for practical applications …”

“…The electropromoted reactor has already been evaluated successfully for hydrocarbon oxidation and NO reduction by C 2 H 4 or C 3 H 6 in the presence of O 2 using both conventional thick films and thin sputtered noble metal electrodes. ,− Specifically, the MEPR with 22 Rh/YSZ/Pt parallel plate elements was found to promote selective catalytic reduction (SCR) of NO by 450% with near 100% selectivity to N 2 , even in high excess of O 2 (10%) at temperatures 200–300 °C (Figure ) . The corresponding Λ NO and Λ CO2 values were up to 2.4 and 350, respectively, and the rate enhancement ratio of complete C 2 H 4 oxidation was up to 900% .…”

“…366 MEPR units with up to 22 thin Rh/YSZ/Pt or Cu/TiO 2 /YSZ/ Au plate cells were used to investigate the hydrogenation of CO 2 at atmospheric pressure and temperatures 220−380°C. The Rh/ YSZ/Pt cells led to CO and CH 4 formation, and the open-circuit selectivity to CH 4 was less than 5%.…”

“…Moreover, the MEPR was successfully operated and EPOC of ethylene oxidation was induced on active skeletal-Pt-catalysts at flow rates as high as 56 L min −1 (Λ = 30), mean gas residence times of 0.34 s, and reactor space velocities up to 2.7 × 10 4 h −1 , showing the strong potential of this reactor for practical applications. 366 MEPR units with up to 22 thin Rh/YSZ/Pt or Cu/TiO 2 /YSZ/ Au plate cells were used to investigate the hydrogenation of CO 2 at atmospheric pressure and temperatures 220−380 °C. The Rh/ YSZ/Pt cells led to CO and CH 4 formation, and the open-circuit selectivity to CH 4 was less than 5%.…”

A Discussion on the Unique Features of Electrochemical Promotion of Catalysis (EPOC): Are We in the Right Path Towards Commercial Implementation?

“…The reactor is equipped of two external connecting wires for polarization purposes. This reactor has been used, for instance, for the oxidation of ethylene [33,34] and SO 2 [35] on Pt electrodes and reduction of CO 2 on Rh and Cu/TiO 2 electrodes [36]. Also, a MEPR with 22 Rh/YSZ/Pt plates was successfully tested under real conditions for the treatment of an automotive exhaust gas of a diesel engine [37,38].…”