Novel covalent organic polymer-supported Ag nanoparticles as a catalyst for nitroaromatics reduction

Abstract

Herein, we propose a Schiff-base covalent organic polymer (COP) prepared by a condensation reaction between 2,4,6-tris-(2-methoxy-4-formyl-phenoxy)-1,3,5-triazine and p-phenylenediamine. The different amounts of silver nanoparticles were trapped by O and N atoms in the COP and synthesized Ag-COP was used as the catalyst for nitroaromatics reduction. The catalyst structure was confirmed using FTIR, XRD, BET, FESEM, ICP, and TGA analysis. The results show that Ag nanoparticles were evenly distributed on the external part or embedded in the interlayer slots of the COP. Ag-COP catalysts were selected as an efficient nanocatalyst for the reduction of nitroaromatics. The apparent rate kinetic constant (Kapp) and the activity parameter (k') were calculated to be 0.0122 s−1 and 4.06 s−1 g−1, respectively. The catalyst showed a 96.5% conversion after seven successive runs without losing its catalytic activity. The superiority of the COP nanoparticles as an effectual pattern for the elimination of industrial contaminants was confirmed by the results of this experimental research.