Removal of carcinogens in environment: Adsorption and degradation of N′-nitrosonornicotine (NNN) in zeolites

Adsorption of N′-nitrosonornicotine (NNN), one of the tobacco-specific nitrosamines (TSNA), in various zeolites with different pore size and acid-basicity were studied in this paper by in situ infrared technique for the first time. The bulky NNN can be trapped by zeolite KA through the manner inserting the N–NO group into the narrow channel resulting from the strong adsorbate–adsorbent interaction. Thermogravimetric-mass spectrometry (TG-MS) analysis was carried out to recognize the products of NNN degraded in zeolite. NNN cannot desorb from zeolite once to be trapped in the channel of adsorbent, but only degraded to less carcinogenic fragments, which is profitable for removal of this carcinogen in environment and protection of public health.