Air pollution control: The evaluation of TerphApm@MWCNTs as a novel heterogeneous sorbent for benzene removal from air by solid phase gas extraction

Abstract

Benzene is one of the most harmful VOCs pollutions which its control emission is a vital purpose in industries and environment. A new and efficient method based on solid phase gas extraction (SPGE) with Schiff base immobilized on MWCNTs (TerphApm@MWCNTs) as a novel sorbent was used for benzene removal from artificial air after loaded in Robson quartz tubes (RGT). The TerphApm@MWCNTs were synthesized and purified via heat treatment at 60 °C as a new heterogeneous sorbent. In bench scale set up, a system was designed and developed for standard gas generation of benzene in air with difference concentrations, and then was passed through RGT by SKC pump at optimized flow rate. Benzene volatile was absorbed on the TerphApm@MWCNTs and desorbed from it at 80 °C before determined by GC/FID. The important factors such as, temperature, humidity, benzene concentration, amount of adsorbent and flow rate were optimized. The recovery and capacity of benzene capture with 20 mg of TerphApm@MWCNTs were obtained 98% and 492 mg g−1 (25 °C). The flow rate and temperature had highly impact on the removal efficiency and adsorption capacity. According to results, the unique characterization of TerphApm@MWCNTs can be considered as a best adsorbent for benzene removal from air as compare to MWCNTs, SWCNTs, and NAC. Keywords: Benzene, Adsorption, Air pollutant, Schiff base immobilized on MWCNTs, Solid phase gas extraction