Synthesis and characterization of carboxymethyl cellulose/organic montmorillonite nanocomposites and its adsorption behavior for Congo Red dye

Abstract

A series of carboxymethyl cellulose/organic montmorillonite (CMC/OMMT) nanocomposites with different weight ratios of carboxymethyl cellulose (CMC) to organic montmorillonite (OMMT) were synthesized under different conditions. The nanocomposites were characterized by the Fourier transform infrared (FT-IR) spectrophotometer, X-ray diffraction (XRD) method, transmission electron microscope (TEM), scanning electron microscope (SEM), and thermal gravimetric (TG) analysis. The results showed that the introduction of CMC may have different influences on the physico-chemical properties of OMMT and intercalated-exfoliated nanostructures were formed in the nanocomposites. The effects of different reaction conditions on the adsorption capacity of samples for Congo Red (CR) dye were investigated by controlling the amount of hexadecyl trimethyl ammonium bromide (CTAB), the weight ratio of CMC to OMMT, the reaction time, and the reaction temperature. Results from the adsorption experiment showed that the adsorption capacity of the nanocomposites can reach 171.37 mg/g, with the amount of CTAB being 1.0 cation exchange capacity (CEC) of MMT, the weight ratio of CMC to OMMT being 1:1, the reaction time being 6 h, and the reaction temperature being 60°C. The CMC/OMMT nanocomposite can be used as a potential adsorbent to remove CR dye from an aqueous solution.