Inorganics-polyaniline composite as a high-performance adsorbent of NO^sub 2^ from flue gas

As absorbents of NO2 from flue gas with excellent thermal stability, adsorption properties and recyclability are required for practical applications, polyaniline (PANI) stands out as a highly desirable candidate. However, pure PANI is generally aggregated in clusters, thereby impeding its wide utilization. To date, many attempts have been made to disperse PANI with materials that have a highly specific surface area, leading to effectively reduced contact among the PANI particles, thus upgrading the denitrating. Herein, aniline was mixed with attapulgite, vermiculite, and diatomite to reinforce PANI composites using an in situ polymerization method. The results demonstrated that all composites exhibited a higher adsorption capacity towards NO2; especially the Attapulgite/PANI (ATP/PANI) composite, which displayed a high capacity of 4.90 mmol g−1, outperforming the 3.08 mmol g−1 capacity of pure PANI. In addition, a good recyclability of 99% of the original adsorption was observed after 10 cycles. This excellent performance results from the unchanged functionality, improved thermal stability, and modified morphology, which is due to the inorganics. Overall, this study is anticipated to offer the fossil-fuel-based industries an option to combine pollution reduction and waste reclamation.