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An integrated solution for NO x ‐reduction and ‐control under lean‐burn conditions
Author(s) -
Saruhan B.,
Stranzenbach M.,
Mondragón Rodríguez G. C.
Publication year - 2007
Publication title -
materialwissenschaft und werkstofftechnik
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.285
H-Index - 38
eISSN - 1521-4052
pISSN - 0933-5137
DOI - 10.1002/mawe.200700186
Subject(s) - nox , lean burn , non blocking i/o , catalysis , selectivity , electrolyte , materials science , reduction (mathematics) , selective catalytic reduction , perovskite (structure) , chemical engineering , process engineering , chemistry , combustion , electrode , engineering , organic chemistry , geometry , mathematics
Upcoming emission regulations order highly effective NO x ‐reduction systems in lean‐burn engines requiring new catalytic materials and integrated control of the reduction process. Thus, new approaches for NO x ‐reduction and its monitoring over an On‐Board‐Diagnostic (OBD) system are suggested throughout the globe. A promising attempt is the development of a catalytic system having an integrated NO x ‐sensor, based on selective catalytic reduction process and impedance sensors. The study displays the results achieved both with a perovskite type of self‐regenerative catalyst functioning by H 2 ‐reductant and with impedance NO x ‐sensors. The catalysts were tested at the temperature range of 150 °C to 360 °C yielding NO x conversion rates of 92 % with high selectivity to N 2 . Impedance sensors having NiCr 2 O 4 ‐ and NiO‐SE and PYSZ‐ and FYSZ‐electrolytes are developed and tested at 600 °C under lean atmosphere (5 vol. % O 2 ). Better sensing behaviour towards NO and lower cross‐selectivity towards O 2 , CO, CO 2 and CH 4 have been observed with sensors having NiO‐SE.