Residual antibiotics in water are often persistent organic pollutants. The purpose of this study was to prepare a cellulose nanocrystals/graphene oxide composite (CNCs-GO) with a three-dimensional structure for the removal of the antibiotic levofloxacin hydrochloride (Levo-HCl) in water by adsorption. The scanning electron microscope, Fourier transform infrared (FT-IR), energy-dispersive spectroscopy, X-ray photoelectron spectroscopy and other characterization methods were used to study the physical structure and chemical properties of the CNCs-GO. The three-dimensional structure of the composite material rendered a high surface area and electrostatic attraction, resulting in increased adsorption capacity of the CNCs-GO for Levo-HCl. Based on the Box–Behnken design, the effects of different factors on the removal of Levo-HCl by the CNCs-GO were explored. The composite material exhibited good antibiotic adsorption capacity, with a removal percentage exceeding 80.1% at an optimal pH of 4, the adsorbent dosage of 1.0 g l⁻¹, initial pollutant concentration of 10.0 mg l⁻¹ and contact time of 4 h. The adsorption isotherm was well fitted by the Sips model, and kinetics studies demonstrated that the adsorption process conformed to a quasi-second-order kinetics model. Consequently, the as-synthesized CNCs-GO demonstrates good potential for the effective removal of antibiotics such as levofloxacin hydrochloride from aqueous media.

水中残留的抗生素通常是持久性有机污染物。这项研究的目的是制备具有三维结构的纤维素纳米晶体/氧化石墨烯复合物（CNCs-GO），用于通过吸附去除水中的抗生素左氧氟沙星盐酸盐（Levo-HCl）。用扫描电子显微镜，傅立叶红外光谱仪，能谱仪，X射线光电子能谱仪和其他表征方法研究了CNCs-GO的物理结构和化学性质。复合材料的三维结构具有较高的表面积和静电引力，从而提高了CNCs-GO对Levo-HCl的吸附能力。基于Box–Behnken设计，探索了不同因素对CNCs-GO去除Levo-HCl的影响。该复合材料表现出良好的抗生素吸附能力，在最佳pH值为4时，去除率超过80.1％，吸附剂量为1.0 gl^-1，初始污染物浓度为10.0 mg l ^-1，接触时间为4 h。Sips模型很好地拟合了吸附等温线，动力学研究表明吸附过程符合准二级动力学模型。因此，合成后的CNCs-GO展示了从水性介质中有效去除抗生素（如盐酸左氧氟沙星）的良好潜力。