Selective Removal of Acid Fuchsin from Aqueous Solutions by Rapid Adsorption onto Polypyrrole Crosslinked Cellulose/Gelatin Hydrogels

摘要

The dispersion and macroization of nanomaterials have great potential in the development of high-efficiency adsorbents. To address organic dye pollution, two inexpensive and renewable biological resources, gelatin (Gel) and carboxymethyl cellulose (CMC), were crosslinked by nanostructured polypyrrole (PPy) to achieve a novel PPy-hydrogel. The morphology and composition of the CMC/Gel/PPy hydrogels were characterized. The result shows that the CMC/Gel solution can provide an excellent condition for the dispersion of polypyrrole (PPy). Based on the combination of PPy and the biomass matrix, specific adsorption sites can be formed by the synergistic effect of the functional groups derived from CMC, Gel and PPy. The CMC/Gel/PPy hydrogel has an exclusive adsorption of acid fuchsin (AF). Furthermore, the adsorption process of AF on the CMC/Gel/PPy hydrogel was investigated, and influencing factors, such as adsorbent dosage, temperature, initial dye concentration and adsorbent recyclability, were discussed in detail. Under optimal conditions, the CMC/Gel/PPy hydrogel can reach an adsorption equilibrium within 50 minutes in a 60 mg/L AF solution at 24 degrees C, and the AF removal efficiency was approximately 94%. It was also observed that the AF removal efficiencies of CMC/Gel/PPy remained almost unchanged after at least seven consecutive adsorption-desorption cycles.