Almojil Sattam Fahad, Almohana Abdulaziz Ibrahim
Department of Civil Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh, 11421, Saudi Arabia.
Department of Civil Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh, 11421, Saudi Arabia.
Environ Res. 2025 Feb 15;267:120542. doi: 10.1016/j.envres.2024.120542. Epub 2024 Dec 18.
This study develops a magnetic composite from pistachio shell biochar (PSBC/CoFe₂O₄) modified with MOF-808 for removing methylene blue (MB) dye and diazinon (DA) pesticide from water. The composite, with a surface area of 151.53 m/g and magnetic saturation of 19.653 emu/g, allowed easy separation from solutions. Key adsorption factors such as pH, temperature, contact time, adsorbent dosage, and initial pollutant concentration were optimized. Maximum removal efficiencies of 99.32% for MB and 99.14% for DA were achieved at adsorbent dosages of 1 g/L for MB and 1.5 g/L for DA, initial concentrations of 5 mg/L, temperatures of 55 °C, contact times of 60 min for MB and 80 min for DA, and pH levels of 9 for MB and 6 for DA. Thermodynamic analysis confirmed that the adsorption process is spontaneous and endothermic, with enthalpy values of 55.091 kJ/mol for MB and 42.028 kJ/mol for DA, while entropy values indicated increased randomness during adsorption. Kinetic studies revealed that adsorption involved both physical and chemical interactions, with intraparticle diffusion not being the rate-limiting step. The Freundlich isotherm model provided the best fit (R = 0.971 for MB and 0.988 for DA), highlighting heterogeneous surface interactions. The composite showed higher adsorption capacities for MB (31.44 mg/g) than for DA (21.49 mg/g) and exhibited excellent regeneration potential, performing better in deionized water due to the inhibitory effects of salts in non-deionized water.
本研究开发了一种用MOF - 808改性的开心果壳生物炭磁性复合材料（PSBC/CoFe₂O₄），用于去除水中的亚甲基蓝（MB）染料和二嗪农（DA）农药。该复合材料的表面积为151.53 m/g，磁饱和度为19.653 emu/g，便于从溶液中分离。对pH、温度、接触时间、吸附剂用量和初始污染物浓度等关键吸附因素进行了优化。在MB吸附剂用量为1 g/L、DA吸附剂用量为1.5 g/L、初始浓度为5 mg/L、温度为55℃、MB接触时间为60 min、DA接触时间为80 min、MB的pH值为9、DA的pH值为6的条件下，MB和DA的最大去除效率分别达到99.32%和99.14%。热力学分析证实，吸附过程是自发的且吸热的，MB的焓值为55.091 kJ/mol，DA的焓值为42.028 kJ/mol，而熵值表明吸附过程中随机性增加。动力学研究表明，吸附涉及物理和化学相互作用，颗粒内扩散不是限速步骤。Freundlich等温线模型拟合效果最佳（MB的R = 0.971，DA的R = 0.988），突出了非均相表面相互作用。该复合材料对MB的吸附容量（31.44 mg/g）高于对DA的吸附容量（21.49 mg/g），并表现出优异的再生潜力，由于非去离子水中盐的抑制作用，在去离子水中表现更好。
