Abstract:
In this work, we synthesized and characterized the mesoporous adsorbent for VOCs adsorption bysol gel method using Tetraethoxysilane (TEOS) as a precursor and surfactants as templates. Factorsaffecting the adsorptive capacity were investigated: (1) Types of surfactants i.e., Cationic Type:Cetyl Trimethyl Ammonium Bromide (CTAB), Anionic Type: Sodium Dodecyl Sulfate (SDS) andNonionic Type: Polyoxyethylene Cetyl Ether (Brij56); (2) The molar ratio of H20 to TEOS;(3) Molar ratio of surfactant to TEOS; (4) The pH condition of precursor (Acidic and basicconditions). The adsorptive capacity of the mesoporous adsorbent was evaluated by the adsorptionof toluene and formaldehyde.The experimental results showed that pore volume and pore diameter of the adsorbent increasedwith precursor pH and with the molar ratio of surfactant to TEOS. As a result, the adsorptivecapacity for toluene and formaldehyde increased with the molar ratio of surfactant to TEOS.However, the molar ratio of Hp to TEOS had no effect on the VOCs adsorptive capacities. Theadsorbent using CTAB at the molar ratio to TEOS of 0.375 with basic condition yielded themaximum toluene and formaldehyde adsorption capacities, i.e., 1.2639 g-toluene!g-adsorbent and1.1297 g-formaldehyde!g-adsorbent. The xerogel with no templates yielded the toluene andformaldehyde adsorptive capacities much lower than those adsorbents with templates.