Adsorption Behavior Studies of Picric Acid on Mesoporous MCM-41

Abstract

The presence of nitrophenols in wastewater is of great environmental concern. In this paper, mesoporous silicate MCM-41 has been prepared by the hydrothermal method and characterized by XRD, the nitrogen adsorption isotherm, and elemental analysis. Adsorption behaviors of 2,4,6-trinitrophenol (picric acid) on the calcined and uncalcined mesoporous MCM-41 adsorbents were studied. The experimental adsorption isotherm was successfully described by the Langmuir model. The pH effect, adsorption kinetics, and breakthrough curves were studied by batch and column methods. The adsorption capacity of picric acid varied significantly with the pH of the solution. It was found that the adsorption capacity is very high in the pH range of 1.4−4.0 and adsorption decreases with increasing pH value.