Facile ultrasound assisted assembly of urea linked organogelator for phase selective recovery of chlorinated solvents

Abstract

Due to rapid industrialization, there is an increased consumption of organic solvents especially chlorinated solvents and their accidental leakage is difficult to circumvent. Although several amide and imine linked organogelators have been developed, very few are suitable for efficient gelation of harmful chlorinated solvents. Herein, for the first time, we propose the synthesis of urea linked supramolecular Low Molecular Weight Organogelators (OG) for efficient phase selective recovery of aromatic chlorinated solvents. The gelation was induced rapidly by sonication, unlike the prolonged conventional heating cooling cycle. Gelator was characterised using CP-MAS, FTIR, TGA, FESEM and DSC. Under optimal conditions an effective self-assembling was observed in the presence of a variety of chlorinated solvents. CHCl3, CCl4, aromatic chlorinated solvents like chlorobenzene, 2-chlorotoluene, 3-chlorotoluene and chlorotoluene in preference to other organic solvents. The role of chlorinated solvent in self-assembling was proposed. Further, practical application for the recovery of the solvents is demonstrated by phase selective gelation studies. With high solvent recovery and retention rate of > 95 %. This work signifies the role of urea based supramolecular gelators in the potential recovery of leaked chlorinated solvents from water.