Direct generation of poly(ionic liquids) on mesoporous carbon via Diels–Alder and multicomponent reactions for ultrafast adsorptive removal anionic organic dye with high efficiency

Abstract

The porous materials have been extensively explored for various applications especially for the environmental treatment. In this work, we reported a novel strategy for the surface modification of mesoporous carbon (MC) that relied on an efficient and green Diels–Alder [4 + 2] cycloaddition and the multicomponent Radziszewski reactions for the first time to in-situ generate poly (ionic liquids) (PIL) on the surface of MC. The resulting MC@PIL composites have been characterized using a series of instrumental techniques to elucidate their morphology, chemical compositions and other properties. Batch experiments towards adsorbing Congo red (CR) with contact time, initial concentration, variable pH and reaction system temperature were conducted to evaluate the adsorption behaviors. Furthermore, thermodynamic analysis of adsorption process is also discussed. The results demonstrated that CR could be rapidly adsorbed on MC-PIL composites within 10 min and displayed obvious enhancement adsorption capacity (331.49 mg/g) towards CR as compared with pristine MC. In addition, the adsorption/desorption cycle of the MC@PIL composites was also tested. The results show that the adsorption capacity of the third adsorption-desorption cycle can reach 199.0223 mg/g and desorption yield above 80%. Considered the good designability of molecules involved in Radziszewski reaction, many functionalized MC could thus be fabricated and these PIL functionalized composites should be efficient and promising candidates for removal of different pollutants from wastewater.