National School of Engineers of Sfax, Laboratory of Plant Improvement and Valorization of Agricultural Resources, P.O. Box 1173, 3038 Sfax, Tunisia E-mail:
Laboratory of Analysis, Treatments and valorization of Pollutants of the Environment and Products, Faculty of Pharmacy, Monastir, Tunisia.
Water Sci Technol. 2021 Mar;83(6):1384-1398. doi: 10.2166/wst.2021.075.
Adsorption of direct red 80 (DR 80) and methylene blue (MB) from aqueous solutions on potato peels (PP) has been compared. The use of peels in decontamination technology is very promising given the near zero-cost for the synthesis of those adsorbents. The selected potato peels were first analyzed by scanning using electron microscopy (SEM) and Fourier transforms infrared spectroscopy (FTIR). Then the adsorption behavior was studied in a batch system. The adsorption process is affected by various parameters such as the solution pH (2-11), the initial concentration of the dye (20, 50, 100, 150 and 200 mg L), the adsorbent dose (0.1-3%), the temperature (303.16 K, 313.16 K, and 323.16 K), agitation (up to 250 rpm), as well as the contact time. Adsorption isotherms of the studied dye on the adsorbent were determined and compared with the Langmiur, Freundlich and Temkin adsorption models. The results show that the data was most similar to the Freundlich isotherm (R = 0.99). The maximum adsorption capacities (Q) of MB and DR 80 by the PP at temperatures 303.16 K, 313.16 K and 323.16 K were found to be approximately 97.08 mg g; 45.87 mg g; 61.35 mg g and 27.778 mg g; 45.45 mg g; and 32.258 mg g. The kinetic data was compared to the pseudo-first-order, pseudo-second-order, and intraparticle diffusion models. This revealed that adsorption of methylene blue onto PP abided mostly to the pseudo-second-order kinetic model. Calculations of various thermodynamic parameters such as enthalpy change (ΔH), entropy change (ΔS), and free energy change (ΔG) display the endothermic and spontaneous nature of the adsorption process.
已比较了从水溶液中用马铃薯皮（PP）吸附直接红 80（DR 80）和亚甲蓝（MB）。鉴于这些吸附剂的合成成本几乎为零，因此在去污技术中使用果皮非常有前景。首先使用电子显微镜（SEM）和傅里叶变换红外光谱（FTIR）对所选的马铃薯皮进行了扫描分析。然后在批处理系统中研究了吸附行为。吸附过程受各种参数的影响，例如溶液 pH 值（2-11）、染料的初始浓度（20、50、100、150 和 200mg/L）、吸附剂剂量（0.1-3%）、温度（303.16K、313.16K 和 323.16K）、搅拌（最高 250rpm）以及接触时间。测定了研究用染料在吸附剂上的吸附等温线，并与朗缪尔、弗罗因德利希和腾肯吸附模型进行了比较。结果表明，数据与弗罗因德利希等温线最相似（R=0.99）。在 303.16K、313.16K 和 323.16K 温度下，PP 对 MB 和 DR 80 的最大吸附容量（Q）分别约为 97.08mg/g、45.87mg/g、61.35mg/g和 27.778mg/g、45.45mg/g、32.258mg/g。将动力学数据与准一级、准二级和内扩散模型进行了比较。这表明，亚甲蓝吸附到 PP 上主要符合准二级动力学模型。计算各种热力学参数，如焓变（ΔH）、熵变（ΔS）和自由能变（ΔG），显示了吸附过程的吸热和自发性质。
