Polyaniline : an innovative sampling support/adsorbent for VOCs in air matrices

Polyaniline (PANI)-based materials for removal of volatile organic compounds (VOCs) from air and their monitoring by rapid absorption/desorption processes have been developed and the results are here presented. Different PANIs were synthesized as emeraldine salt and base by different synthetic approaches1-3 and their VOCs’ absorption/desorption efficiency were evaluated by GC/MS technique and compared with the performances of activated carbon. However, in contrast to activated carbon, VOCs’ extraction from PANI-based sorbents was carried out with an organic solvent less toxic than CS2, typically used in official methods, and a complete regeneration of the polymers was realized by rapid washing with methanol. The recycle of these polymers was evaluated up to five tests. Moreover, the dependence of the PANIs’ activity from their surface area, porosity and morphology was investigated. The results showed that the performances of PANIs are strictly related to their surface area. In fact, it was observed that the higher the surface area the greater the performances. These results open the way to innovative applications of PANI-based materials in environmental field where the possibility to use green protocols and reusable materials represents a crucial goal. 1. Stejskal J., Gilbert R.G., Pure Appl. Chem. 74:857-862, 2002. 2. Chen Z., Della Pina C. et al., J. Catal. 267:93-96, 2009. 3. Castagna R., Tunesi M. et al., J. Appl. Polym. Sci. 43885(1-10), 2016.