Carbon Monoxide Trend, Meteorology, and Three-Way Catalysts in Mexico City

Autor: Beatriz Silva, Pilar Ovalle, Héctor G. Riveros, Alfredo Alba, Ernesto Sandoval
Rok vydání: 1998
Předmět:
Zdroj: Journal of the Air & Waste Management Association. 48:459-462
ISSN: 2162-2906
1096-2247
Popis: From the analysis of data of the Inspection/Maintenance (I/M) program, and of the long-term trend of ambient CO concentrations in Mexico City, it is inferred that three-way catalysts (TWCs) have a 45% efficiency, well below the expected 90% value. The most probable causes are sulfur poisoning, lead contamination, and ceramic breakage due to bumps and potholes on the streets. Also, we have found a ratio between the average daily peak value of atmospheric CO and gasoline consumption: (11 +/- 1) ppbCO/MLm (million liters of gasoline per month) in 1988 decaying to (10 +/- 1) in 1991 for Mexico City before the introduction of TWCs. In addition, we found a correlation between the monthly averages of CO daily peak and meteorological variables, explaining most of the seasonal changes using only the intensity of the inversion layer and surface wind speed.
Databáze: OpenAIRE