Effective Removal of Dyes from Aqueous Solutions by a Gelatin Hydrogel

Adsorptive removal of dyes from industrial wastewater has attracted intensive interests in recent years. Hydrogels is a kind of promising adsorbent in dyes removal owing to the simple synthesis and convenient application. A biodegradable and recyclable gelatin hydrogel (GH) was synthesized by a convenient approach in this work. The as-prepared GH was used to remove dyes in aqueous solution. The results indicated that the GH had excellent adsorption capacity for various dyes and the maximum adsorption capacities of crystalline violet (CV), methyl orange (MO), acid fuchsin (AF), congo red (CR), malachite green (MG), and methylene blue (MB) were 138.89 mg/g, 72.63 mg/g, 66.29 mg/g, 64.84 mg/g, 64.64 mg/g, and 60.32 mg/g, respectively. Moreover, the dye removal efficiency was still more than 60% after five consecutive adsorption–desorption cycles and the shape of the GH kept well. Therefore, GH can be used as an environmentally friendly and effective adsorbent to remove virous dyes from printing and dyeing wastewater.