No abstract

Aniline is a toxic organic pollutant that is abundantly present in the environment. One of approaches to remove the aniline is by adsorption process. In this study, mesoporous carbon nitride (MCN) was proposed for the first time to be a potential adsorbent for aniline. The adsorption studies were carried out at room temperature on the aniline solution with various initial concentrations for both bulk carbon nitride (BCN) and MCN. Owing to its larger surface area, the MCN showed much higher adsorption capacity towards aniline compared to the BCN. This result indicated that adsorbent with large surface area is very crucial in the adsorption of aniline. Comparison study was also carried out using mesoporous silica, MCM-41, which was reported to act as a good adsorbent for aniline. The adsorption capability of MCN was found to be higher than that of MCM-41. It was suggested that the MCN with larger pore diameter might have more suitable and favourable adsorption sites for aniline compared to MCM-41. This study obviously showed that MCN would be a new potential adsorbent for removal of aniline.

Mesoporous carbon nitride (MCN) was used for the first time as a thermal catalyst for the removal of aniline. While bulk carbon nitride (BCN) and mesoporous silica (MCM-41) did not show any catalytic activities, the MCN showed aniline removal (33%) at 398 K. It was revealed that the much higher activity of the MCN originated from the presence of mesoporosity and suitable adsorption sites for the reaction to occur.The nature of aniline adsorption on MCN was found to fit well to the Freundlich adsorption model. The evidence on the interactions between aniline and MCN was supported by fluorescence and FTIR spectroscopies. It was suggested that the interactions between MCN and aniline involved both weak p to p stacking and strong hydrogen bonding, which were important to initiate the catalytic removal of aniline.