Ionic liquid based nanoporous organosilica supported propylamine as highly efficient adsorbent for removal of congo red from aqueous solution

Abstract

A novel ionic liquid based nanoporous organosilica supported propylamine (ILNO-NH2) has been prepared and characterized and its efficiency in the removal of congo red dye from aqueous solutions has been investigated. The ILNO-NH2 was synthesized via chemical attachment of 3-aminopropyl-trimethoxysilane on an ionic liquid based ordered nanoporous organosilica in toluene at reflux. The ILNO-NH2 was then successfully applied in the removal of congo red (CR) under acidic conditions. The effect of initial dye concentration, isotherm studies and the enforceability of pseudo-first and second order as well as Elovich kinetic models were investigated. The optimum conditions were achieved by using 0.025 g/50 mL of adsorbent, 40 mg/L of congo red at 30 min of contact time and pH 4.0. The study showed that the adsorbent is very efficient with the maximum adsorption capacity of 43.10 (mg/g) under applied conditions and could be recovered without significant decrease in its stability and structural order. Keywords: Nanoporous organosilica, Congo red (CR), Ionic liquid, Isotherm, Kinetic, Adsorption