Conjugated porous polymers for gaseous toluene adsorption in humid atmosphere

Abstract

Two triphenylamine-based conjugated porous polymers, 1,3,5-triformylbenzene-4,4′4″-triaminotriphenylamine (TFB-TPA) and 2,4,6-triformylphloroglucinol-4,4′4″-triaminotriphenylamine (TFP-TPA) fabricated via Schiff-base reaction with π-conjugated skeletons and hierarchical pore structures were explored as adsorbents for the removal of gaseous toluene under humid environment. The effects of humidity, initial toluene concentration, adsorption temperature and surface functional groups on the adsorption capacity were investigated. The equilibrium isotherms, adsorption kinetics and structure-activity relationship were further analyzed. Experiment results suggest that the as-prepared TFB-TPA exhibits acceptable adsorption performance for gaseous toluene in humid atmosphere owing to the aromatic backbone and the hierarchically micro-meso-macroporous structure and the Freundlich equation agrees very well with the isothermal data, the pseudo-second-order kinetic model is more suitable to describe the adsorption kinetics. This study may not only show the application potential of triphenylamine-based conjugated porous polymers in toluene adsorption, but also provide a detailed understanding of the adsorption process of toluene for practical application.