Phosphoric acid modified montmorillonite clay: A new heterogeneous catalyst for nitration of arenes

The easily available montmorillonite clay is treated with phosphoric acid and 10 wt.% is found to be the optimum concentration of phosphoric acid that can be adsorbed chemically on the surface of the clay. Acidity of this phosphoric acid treated montmorillonite clay (PAM) is determined by volumetric as well as potentiometric titration and characterized. Catalytic efficacy of PAM in nitration of various aromatic compounds is reported. (C) 2014 Elsevier B.V. All rights reserved.