Impact of Modified Coal with Alkyl or Mixed Alkyl-Aryl Layer on the Performance of Heterogeneous Cellulose Acetate Membranes.

Abstract

Heterogeneous cellulose acetate asymmetric reverse osmosis membranes were prepared using coal particles modified with alkyl and mixed alkyl/aryl groups. Aryldiazonium salts and alkyl halides were used as sources of organic radicals that interact with the coal surface to form functional layers. Attenuated Total Reflectance Fourier-Transform Infrared (ATR-FTIR) was employed to confirm the presence of functional layers on the coal surface, while the morphology of membranes was characterized by Scanning Electron Microscopy, SEM. Functionalized coal particles with alkyl and/ or aryl moieties containing different substituents (-COOH, -NO2, -NH2) that have been used to prepare heterogeneous membranes, have shown a noticeable impact in reverse osmosis parameters: permeability and rejection, which were significantly improved in most tested membranes.