A green hydrogel from biochar and chitosan (BC) was synthesized as an adsorbent to remove ciprofloxacin (CIP) and enrofloxacin (ENR) from aqueous solution. BC hydrogel was prepared through an eco-friendly and inexpensive approach, using chitosan extracted from shrimp shells and biochar produced from rice husk. The physicochemical characteristics of BC were determined by SEM, FTIR, and pH${}_{\mathrm{PZC}}$. A Taguchi method was employed to determine the optimal conditions for adsorption of CIP and ENR, and these were found to be 1.0 and 1.5 g/L of BC adsorbent for 300 and 450 min at pH=7, respectively. Adsorption kinetics of CIP and ENR were found to follow a pseudo-second-order model. Langmuir, Freundlich, and Temkin adsorption isotherms were applied to illustrate the adsorption equilibrium of veterinary antibiotics. The results indicate that CIP and ENR fit the Langmuir isotherm well with maximum adsorption capacities of 106.038 and 100.433 mg/g, respectively. Also, the BC hydrogel adsorption mechanism were combined with electrostatic $\pi$–$\pi$ interactions and hydrogen bonds. Furthermore, a toxicity survey of microalgae Chlorella sp. for 72 h confirmed that the BC hydrogel is non-toxic for the environment.

合成了生物炭和壳聚糖（BC）的绿色水凝胶作为吸附剂，以从水溶液中去除环丙沙星（CIP）和恩诺沙星（ENR）。BC水凝胶是通过生态友好且廉价的方法制备的，使用的是从虾壳中提取的壳聚糖和稻壳制成的生物炭。通过SEM，FTIR和pH值测定BC的理化特性${}_{\mathrm{PZC}}$。采用Taguchi方法确定CIP和ENR的最佳吸附条件，在pH = 7的条件下，分别在300和450 min时分别为1.0 g / L和1.5 g / L的BC吸附剂。发现CIP和ENR的吸附动力学遵循伪二级模型。Langmuir，Freundlich和Temkin吸附等温线用于说明兽用抗生素的吸附平衡。结果表明，CIP和ENR非常适合Langmuir等温线，最大吸附容量分别为106.038和100.433 mg / g。此外，BC水凝胶的吸附机理与静电相结合$\pi$–$\pi$相互作用和氢键。此外，对微藻小球藻的毒性调查。持续72小时证实BC水凝胶对环境无毒。