A multi-functionalized montmorillonite for co-operative catalysis in one-pot Henry reaction and water pollution remediation

Abstract

The present work provides a simple approach for the surface modification of an acid activated montmorillonite clay with both acid and base (–SO₃H and –NH₂) functional groups. FTIR, ²⁹Si and ¹³C CP MAS NMR spectroscopy studies confirm the grafting of the organic functional moieties. These materials were also extensively characterized by various other characterization techniques like XRD, N₂ adsorption–desorption analysis, XPS, FE-SEM, TEM, etc. This multi-functionalized material was investigated as a heterogeneous catalyst for one-pot deacetalization–nitroaldol (Henry) reaction giving a 99.2% product yield in just 2 h. This material also showed outstanding adsorption capacity for the heavy metal cations and can be utilized as a potential candidate for the remediation of contaminated water. This material is potent enough to carry out the Henry reaction as well as adsorption for many runs without any significant loss of its activity.