High emission reduction performance of a novel organic-inorganic composite filters containing sepiolite mineral nanofibers

In this work, a new organic-inorganic composite filter was prepared. The thickness, pore size, air permeability, bursting strength and microstructure were characterized systematically, proving that coatings had regulatory effect on filters physical properties. Benefitting from the distinct coatings containing 5% sepiolite nanofibers after five times dilution, the physical properties of corresponding air filter exhibits the most favorable performance and meet the standard of air filter. When used as fuel filter, it satisfies the fuel filter standard and achieves the best performance after six times dilution. The contrast test on engine emission was taken based on auto filters coated with/without as prepared nanofibers. An obvious decrease in the emission of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO(x)) can be observed after installation of composite filter on vehicles. Under the high idle condition, gasoline engine emission decreased by 8.13%, 11.35% and 44.91% for CO, HC and NO(x), respectively. When tested in the low idle condition, engine emission reduced by 0.43%, 1.14% and 85.67% for CO, HC and NO(x), respectively. The diesel engine emissions of CO, NO(x) and total amount of HC and NO(x) decreased by 32.26%, 3.28% and 4.66%, respectively. The results illustrate the composite installation exhibits satisfactory emission reduction effect.