The elimination of diclofenac traces from aqueous environments is important. In this research, the effect of alkaline (NaOH) pretreatment on clinoptilolite before its modification with a surfactant (HDTMA) for diclofenac adsorption under the speculation of the sole presence of diclofenac in the aqueous solution is investigated. The results are compared through isotherm, kinetic, and thermodynamic studies and supplemented by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), Brunauer–Emmett–Teller (BET), and the zeta potential analyses. The contact time was investigated in a 0–180-min range. The pH effect was studied in a range of 5–10 because of diclofenac dissociation below pH = 5. The effect of the temperature on diclofenac adsorption was also considered by establishing the experiments at 25, 35, and 45 °C. For HDTMA-modified clinoptilolite, Temkin, and for NaOH-HDTMA-modified clinoptilolite, Dubinin–Radushkevich, and Freundlich isotherm models and in both cases, the pseudo-second-order kinetic model fitted the experimental data best. All the enthalpy and the entropy changes were negative, suggesting exothermic adsorption with a decrease in the degree of freedom of diclofenac anions after the adsorption. Furthermore, diclofenac physisorption was confirmed through isotherm and kinetic studies.

从水性环境中消除双氯芬酸痕迹很重要。在这项研究中，研究了碱（NaOH）预处理对斜发沸石的影响，然后推测在水溶液中仅存在双氯芬酸，然后用表面活性剂（HDTMA）对其进行改性以吸附双氯芬酸。通过等温，动力学和热力学研究对结果进行比较，并辅以傅立叶变换红外光谱（FTIR），扫描电子显微镜（SEM），Brunauer–Emmett–Teller（BET）和zeta电位分析。在0-180分钟的范围内研究了接触时间。由于双氯芬酸在pH = 5以下解离，因此在5-10范围内研究了pH效应。通过在25、35和45°C下建立实验，还考虑了温度对双氯芬酸吸附的影响。对于HDTMA修饰的斜发沸石，Temkin，对于NaOH-HDTMA修饰的斜发沸石，Dubinin–Radushkevich和Freundlich等温线模型，在这两种情况下，伪二级动力学模型最适合实验数据。所有的焓和熵变化均为负，表明放热吸附，并且吸附后双氯芬酸阴离子的自由度降低。此外，通过等温线和动力学研究证实了双氯芬酸的物理吸附。提示放热吸附，吸附后双氯芬酸阴离子的自由度降低。此外，通过等温线和动力学研究证实了双氯芬酸的物理吸附。提示放热吸附，吸附后双氯芬酸阴离子的自由度降低。此外，通过等温线和动力学研究证实了双氯芬酸的物理吸附。