The present work describes the production of carboxymethylcellulose (CMC) -hydroxyethyl cellulose (HEC) hydrogel films using citric acid as a non-toxic crosslinking agent, for a potential application in wastewater treatment. After their synthesis, all films were then characterized through Fourier-transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), UV-Visible spectroscopy (UV-Vis) and swelling study. During these measurements, the successful crosslinking of the hydrogel film was validated; films also possess good thermal stability, a high transmittance under the visible light region, confirming their transparency, and excellent swelling ability in neutral and in acidic media. Therefore, the as-produced films were then used as a potential adsorbent for the removal of cadmium (Cd) and methylene blue (MB) from concentrated aqueous solutions. The adsorption ability of each film was evaluated thanks to thermodynamic and kinetic studies showing that the adsorption equilibrium was reached within 1h for Cd and 3h for MB. Furthermore, the analysis of the adsorption kinetics highlights that all the data could be fitted by a pseudo-second order model, and the adsorption isotherms could be sufficiently described by Langmuir isotherm model for the two studied pollutants. From this analysis, the maximum adsorption capacities, determined by Langmuir model, are close to 126.58 and 769.23 mg/g for Cd and MB, respectively. Moreover, the sorption capacities of Cd and MB in films both increase with the temperature. According to the thermodynamic parameters, cadmium and methylene blue adsorption processes using tested films are favorable, spontaneous, and endothermic.

本工作描述了使用柠檬酸作为无毒交联剂生产羧甲基纤维素（CMC）-羟乙基纤维素（HEC）水凝胶薄膜的潜在应用。合成后，然后通过傅立叶变换红外光谱（FTIR），热重分析（TGA），紫外可见光谱（UV-Vis）和溶胀研究对所有薄膜进行表征。在这些测量过程中，验证了水凝胶薄膜的成功交联。薄膜还具有良好的热稳定性，在可见光区域下的高透射率，确认其透明性以及在中性和酸性介质中的优异溶胀能力。所以，然后将所生产的薄膜用作潜在的吸附剂，用于从浓水溶液中去除镉（Cd）和亚甲基蓝（MB）。通过热力学和动力学研究评估了每种膜的吸附能力，结果表明，镉在1h内达到吸附平衡，而MB则在3h内达到吸附平衡。此外，对吸附动力学的分析表明，所有数据都可以通过拟二阶模型拟合，并且吸附等温线可以通过Langmuir等温线模型充分描述两种被研究的污染物。根据该分析，由Langmuir模型确定的最大吸附容量分别接近Cd和MB的126.58和769.23 mg / g。此外，薄膜中Cd和MB的吸附容量均随温度而增加。