Facile preparation of sodium alginate gel beads enhanced by polyamino-modified 3D carbon for efficient remediation of organic dyes in wastewater

The existence of organic dyes wastewater had caused serious harm to the environment and human beings. Herein, in this study, a simple and efficient method was selected to synthesize sodium alginate gel beads adsorbent (CPS-Bead) with porous structure and high adsorption performance. Interestingly, the addition of polyamino-modified 3D carbon materials (GO-CNT) enhanced the related properties of gel beads. Moreover, the well-designed adsorbent was used to remove methylene blue (MB), malachite green (MG), crystal violet (CV), and congo red (CR) from dyes wastewater. The results showed that the adsorption capacity of CPS-Bead on MB, MG, CV and CR could reach the highest of 2191.39 mg/g, 2201.69 mg/g, 1669.11 mg/g and 2096.04 mg/g at 318 K, respectively. The kinetic behavior and the isotherm behavior of CPS-Bead was more consistent with the nonlinear model of pseudo-second-order dynamics and the Langmuir isotherm model, and the thermodynamic data showed that the adsorption process of the four dyes was automatic. In addition, CPS-Bead also demonstrated excellent adsorption performance in cyclic experiments, selectivity experiments and adsorption column experiments, which could selectively and continuously adsorb different dyes. Overall, the prepared gel beads not only showed outstanding adsorption capacity, but also the had an excellent reusability, besides, CPS-Bead had great potential industrial applications.