Adsorption of acid fuchsin onto the chitosan-montmorillonite composite

The chitosan-montmorillonite composites (CTS-MMT) were prepared by CTS in combination with Na-type montmorillonite (Na-MMT). The composites were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The effects of initial pH value of the solution, adsorbent dose, the mass ratio of CTS to Na-MMT, the adsorption temperature, and contact time on acid fuchsin (AF) removal efficiency were investigated. The results indicated that the CTS could be successfully intercalated into the interlayers of Na-MMT. With the increase in content of CTS, some of them may be distributed on the surfaces of the clay and the AF removal efficiency can reach 80.2% using CTS-MMT as adsorbent to treatment AF wastewater (the AF concentration 20mg/L) under the condition of pH, 5; adsorbent dose, 5g/L; the mass ratio of CTS to Na-MMT, 0.25:1; adsorption temperature, 40 degrees C; and contact time, 90min. Meanwhile, it was shown that the adsorption processes were better fitted by pseudo-second-order model and the Freundlich model.