Department of Civil Engineering, College of Engineering, King Saud University, P.O. Box 800, Riyadh, 11421, Saudi Arabia.
Department of Mechanical Engineering, College of Engineering, King Khalid University, Abha, 61421, Saudi Arabia.
Environ Sci Pollut Res Int. 2023 Feb;30(7):18419-18437. doi: 10.1007/s11356-022-22821-3. Epub 2022 Oct 10.
In this study, hydroxyapatite@Mn-Fe composite was used as a novel adsorbent to eliminate Nile blue (NB) dye and hexavalent chromium ion (Cr(VI)) from aqueous media. Different analyses such as FTIR, Map, SEM, EDX, BET, and XRD were used to study the characteristics of the composite. The highest sorption efficiencies of Cr(VI) and NB at pH 2 and 10 were 97.63% and 98.83%, respectively, which are significant values. Equilibrium and kinetic studies of the sorption process showed that the Freundlich isotherm model and pseudo-second-order kinetic model can better describe the equilibrium and kinetic behavior of the sorption process. According to the Langmuir model, the maximum sorption capacities of NB dye and Cr(VI) ion using the hydroxyapatite@Mn-Fe composite were 0.259 and 0.938 mmol/g, respectively. Also, the results of the thermodynamic study showed that the sorption process is favorable (ΔS° = - 34.2 kJ/mol·K for Cr(VI) and - 144.6 kJ/mol·K for NB), spontaneous (ΔG° < 0), and exothermic (ΔH° = - 27.99 kJ/mol for Cr(VI) and - 64.2 kJ/mol for NB). Moreover, the desorption process of both contaminants using the hydroxyapatite@Mn-Fe composite showed that the HSO solution with a concentration of 3 mol/L can remove both contaminants separately with the highest efficiency. Furthermore, the reusability study indicated that the composite can be used in five reuse cycles without significant decrease in its efficiency. Besides, the composite was able to eliminate color, turbidity, COD, and BOD from the textile wastewater with removal efficiencies of 93.06, 81.61, 76.05, and 71.88%, respectively. To the best of our knowledge, hydroxyapatite@Mn-Fe composite was synthesized and used for the first time to remove Cr(VI) ions and NB dye. In general, the aforementioned composite is recommended for industrial wastewater treatment.
在这项研究中，羟基磷灰石@Mn-Fe 复合材料被用作一种新型吸附剂，用于从水介质中去除尼罗蓝（NB）染料和六价铬离子（Cr(VI)）。使用不同的分析方法，如 FTIR、Map、SEM、EDX、BET 和 XRD 来研究复合材料的特性。在 pH 值为 2 和 10 时，Cr(VI)和 NB 的最高吸附效率分别为 97.63%和 98.83%，这是显著的值。吸附过程的平衡和动力学研究表明，Freundlich 等温线模型和拟二级动力学模型可以更好地描述吸附过程的平衡和动力学行为。根据 Langmuir 模型，使用羟基磷灰石@Mn-Fe 复合材料的 NB 染料和 Cr(VI)离子的最大吸附容量分别为 0.259 和 0.938 mmol/g。此外，热力学研究结果表明，吸附过程是有利的（ΔS°=-34.2 kJ/mol·K 用于 Cr(VI)和-144.6 kJ/mol·K 用于 NB），自发的（ΔG°<0）和放热的（ΔH°=-27.99 kJ/mol 用于 Cr(VI)和-64.2 kJ/mol 用于 NB）。此外，使用羟基磷灰石@Mn-Fe 复合材料对两种污染物的解吸过程表明，浓度为 3 mol/L 的 HSO 溶液可以以最高效率分别去除这两种污染物。此外，重复使用研究表明，该复合材料可以在五个重复使用周期内使用，而不会显著降低其效率。此外，该复合材料能够去除纺织废水中的颜色、浊度、COD 和 BOD，去除效率分别为 93.06%、81.61%、76.05%和 71.88%。据我们所知，羟基磷灰石@Mn-Fe 复合材料是首次被合成并用于去除 Cr(VI)离子和 NB 染料。总的来说，建议将上述复合材料用于工业废水处理。
