Abstract The adsorption study of acid dye-eosin yellow (EY) on date palm (Phoenix dactylifera) seed, goethite and their composite was conducted using batch technique. The effects of initial concentration, pH, adsorbent dosage, agitation time and temperature were evaluated, and found to have remarkable influence on the adsorption processes with adsorbents performance in the order; composite (COM)>goethite (GT)>thermally activated carbon (TAC)>chemically activated carbon (CAC)>raw date palm seeds (RDS). The data fitted well into all tested isotherms (Langmuir, Freundlich and Temkin) except RDS which fitted only Langmuir model. The overall maximum adsorption capacity (qm) of 30.30mg/g was reported for the COM. The data fitted perfectly pseudo-second order and film diffusion models. The obtained thermodynamic parameters revealed that the reactions were exothermic (- ΔH), feasible, and spontaneous (- ΔG except RDS). There was decrease in the degree of randomness at the solid-liquid interface (ΔS ranges from -0.02 to -0.27 kJ/mol) excluding COM.

中文翻译：

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酸性染料伊红黄对椰枣种子、针铁矿及其复合物的吸附研究

摘要 酸性染料伊红黄(EY)对枣椰树种子、针铁矿及其复合物的吸附研究采用分批技术进行。考察了初始浓度、pH、吸附剂用量、搅拌时间和温度的影响，发现对吸附过程影响显着，依次为吸附剂性能；复合材料（COM）>针铁矿（GT）>热活性炭（TAC）>化学活性炭（CAC）>生椰枣种子（RDS）。数据与所有测试的等温线（Langmuir、Freundlich 和 Temkin）拟合良好，除了 RDS 仅拟合 Langmuir 模型。据报道，COM 的总体最大吸附容量 (qm) 为 30.30 毫克/克。数据完全符合伪二阶和薄膜扩散模型。获得的热力学参数表明反应是放热的（-ΔH）、可行的和自发的（-ΔG，RDS 除外）。除 COM 外，固-液界面的随机度降低（ΔS 范围为 -0.02 至 -0.27 kJ/mol）。