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SBA-15 was modified by incoporating acidic zeolite fragments or plugging, and showed a significantly enhanced efficiency for the removal of nitrosamines in mild conditions. The impact of pore structure and acidicity of mesoporous materials on their adsorptive feature is examined, in comparison with those coated with copper oxide, in order to prepare new functional materials for environment protection.

The function of zeolites as the capturer of nitrosamines is depicted in this paper. N -nitrosodimethylamine (NDMA) and N -nitrosopyrrolidine (NPYR) can be selectively adsorbed by zeolite NaY or NaZSM-5 in solution or gaseous phase. The adsorption capacity of zeolite is discussed in terms of adsorbate-adsorbent interaction, involving their pore structure and electrostatic attraction along with the impact of adsorption temperature. In addition, one of the tobacco specific nitrosamines, N′ -nitrosonornicotine (NNN), is also employed as a probe to explore how the bulky nitrosamines are adsorbed by zeolites. The especial function of adsorption enables zeolites to be utilized for removal of nitrosamines in environment.

Micro-control of activated carbon surface by metal oxides was performed, in order to eliminate nitrosamines in environment, especially in cigarette smoke for the first time. Coating alumina and zinc oxide can promote the adsorption of nitrosamines in activated carbon, opening new avenues to generating selective adsorption sites on amorphous material through the modification on the polarity of surface.

Adsorption of bulky nitrosamines like N -nitrosohexamethyleneimine (NHMI) and N ′-nitrosonornicotine (NNN) on the zeolite with small pore size was firstly studied by use of TPSR (temperature programmed surface reaction), selective adsorption and FTIR methods, and the adsorption manner was discussed combined with simulation of the structure of nitrosamines. Both NNN and NHMI could be adsorbed on zeolite KA and NaA, furthermore they can be degraded in the process of TPSR, though the pore size of adsorbent was much smaller than the molecular diameter of the adsorbate.