Facile synthesis of three-dimensional graphene-soy protein aerogel composites for tetracycline adsorption

A three-dimensional graphene-soy protein aerogel was prepared and characterized by scanning electron microscopy, Raman, and fourier transform infrared spectroscopy. Both the graphene aerogel (GS0) and the graphene-soy protein aerogel (GS6) were used as adsorbents for the removal of tetracycline from an aqueous solution. The kinetics model (pseudo-first-order, pseudo-second-order, and intraparticle diffusion model), isotherm model (Langmuir, Freundlich, Temkin, and Dubinin-Radushkevich), and pH influences were investigated to characterize the adsorption behaviors. The Langmuir and the pseudo-second-order were best fitted for both GS0 and GS6. Calculated from the Langmuir model, the maximum adsorption capacity of GS0 was 137.0mg/g, while GS6 was 164.0mg/g. Graphene was decorated by low-cost and nontoxic protein with enhanced adsorption performance and low biotoxictiy. Therefore, GS6 is a promising adsorbent material for the preconcentration and separation of antibiotics for environmental remediation.