Carbon Nanotube Filters for Removal of Air Pollutants from Mobile Sources

摘要

The aim of this work was the assessment of the removal of air pollutants from mobile sources by commercial carbon nanotubes (CNTs). For this, the nanomaterial was characterized by different techniques: SEM, EDS, TEM, XRD, BET, and Raman. Subsequently, the CNTs were packed in a stainless steel filters which was designed from different prototypes that were developed during the investigation. Tests were performed in the TO-913 Verificenter Macrover Auto SAQ. Inc. de CV. The results revealed that particle type sand CNTs loading had greater effects on the efficiencies than the membrane type sand pore sizes tested. When collecting NOx, the efficiencies were observed relatively lower, below 20% for loadings of 0.3 - 1.5 mg/cm2. The studied CNTs were multi-walled: two layers, show a nonlinear growth and morphology varied since they are of different diameters and longitudes, it was observed that half of the nanotubes were coated with amorphous carbon. The composition is mainly carbon and oxygen, iron is also present. The adsorption capacity of CNTs was significantly influenced by the different aspects, like model, brand, fuel, year and the conditions of each car. The removal efficiencies of CNTs filters were shown to range from 10% to 95% in average for the CNTs loadings of 0.2 - 1.6 mg/cm2. When collecting CO, CO2, NOx, HC, the efficiencies were shown to range from 5% to 60% given similar CNTs loadings used.