The colored effluents causing environmental pollution pose a threat to the world. This study aims to assess the effectiveness of nickel oxide/zinc oxide/kaolin nanocomposite (NiO/ZnO/Ka) in removing methylene blue (MB) from water. Furthermore, it aims to examine the impact of synergetic adsorption/photocatalytic degradation (APCD) on the MB adsorption capacity as well as the suitability of the nonlinear adsorption isotherm and kinetic modeling in analyzing the process. The composites ZnO/Ka and NiO/ZnO/Ka were synthesized by the sol–gel method and were characterized by X-ray diffraction, Fourier transform infra-red, field emission scanning electron microscopy, and Brunauer–Emmett–Teller. The impacts of various parameters, such as pH, initial concentration of MB, dose, ionic strength, and temperature, on MB removal were studied using adsorption and APCD. The results showed that ZnO/Ka had the maximum adsorption capacity of MB (39.31 mg/g) and the maximum removal (78.61%) under optimal conditions of pH 10, clay dosage of 0.1 g/25 mL, initial concentration of MB 200 mg/L, contact time of 15 min, and 298 K, while NiO/ZnO/Ka showed the maximum adsorption capacity of MB (40.88 mg/g) and maximum removal (83.74%) at pH 7. It was also noticed that Temkin and Fritz–Schlunder models are the best isotherm models, with the highest R² (1 and 0.842) for ZnO/Ka and NiO/ZnO/Ka, respectively. Moreover, the data of adsorption and photodegradation of MB onto ZnO/Ka and NiO/ZnO/Ka were revealed to follow pseudo-first-order and Avrami kinetic models with R² (0.897) for ZnO/Ka and (0.986) for NiO/ZnO/Ka. Overall, NiO/ZnO/Ka showed better removal of MB than ZnO/Ka, and the hybrid process (photodegradation process after adsorption) enhanced the overall efficiency of MB removal than adsorption alone.

造成环境污染的有色污水对世界构成威胁。本研究旨在评估氧化镍/氧化锌/高岭土纳米复合材料 （NiO/ZnO/Ka） 从水中去除亚甲蓝 （MB） 的有效性。此外，它旨在检查协同吸附/光催化降解 （APCD） 对 MB 吸附能力的影响，以及非线性吸附等温线和动力学模型在分析过程中的适用性。采用溶胶-凝胶法合成了复合材料 ZnO/Ka 和 NiO/ZnO/Ka，并通过 X 射线衍射、傅里叶变换红外、场发射扫描电子显微镜和 Brunauer-Emmett-Teller 进行了表征。使用吸附和 APCD 研究了各种参数（如 pH 值、MB 的初始浓度、剂量、离子强度和温度）对 MB 去除的影响。结果表明，在 pH 10、粘土用量 0.1 g/25 mL、初始浓度 MB 200 mg/L、接触时间 15 min、K 298 K的最佳条件下，ZnO/Ka 具有最大吸附量 MB （39.31 mg/g） 和最大去除量 （78.61%），而 NiO/ZnO/Ka 在 pH 值为 7 时表现出最大吸附量 MB （40.88 mg/g） 和最大去除量 （83.74%）。还注意到 Temkin 和 Fritz-Schlunder 模型是最好的等温线模型，ZnO/Ka 和 NiO/ZnO/Ka 的 R² （1 和 0.842） 最高。此外，MB 在 ZnO/Ka 和 NiO/ZnO/Ka 上的吸附和光降解数据显示遵循准一级和 Avrami 动力学模型，ZnO/Ka 为 R² （0.897），NiO/ZnO/Ka 为 （0.986）。 总体而言，NiO/ZnO/Ka 对 MB 的去除效果优于 ZnO/Ka，并且混合过程（吸附后的光降解过程）比单独吸附提高了 MB 去除的整体效率。