The quantitative kinetic and equilibrium adsorption parameters for chlorure de méthylrosaniline (gentian violet, crystal violet) removed by commercial activated carbon were studied by UV–visible spectroscopy.Activated carbon with a high specific surface area 1250 m2/g was characterized by the Brunauer, Emmett et Teller (BET) method and the zero charge point pH (pzc). The adsorption properties of both activated carbon with gentian violet were conducted at variable stirring speed 100–700 trs/min, adsorbent dose 1–8 g/l, solution pH 1–14, initial gentian violet concentration 5–15 mg/l, contact time 0–50 min, and temperature 299–323 K using batch mode operation to find the optimal conditions for a maximum adsorption. The adsorption mechanism of gentian violet was studied using the pseudo-first-order, pseudo-second-order, and Elovich kinetic models. The adsorption kinetics was found to follow a pseudo-second-order kinetic model with a determination coefficient (R2) of 0.999. The Weber–Morris diffusion model was applied for the adsorption mechanism. The equilibrium adsorption data of gentian violet were analyzed by the Langmuir, Freundlich, Elovich, and Temkin models. The results indicate that the Langmuir model provides the best correlation (qmax = 22.727, 32.258 mg/g at 26 and 40°C, respectively). The adsorption isotherms at different temperatures have been used for the determination of thermodynamic parameters, i.e. free energy (ΔG° = − 2.30 to −5.34 kJ/mol), enthalpy (ΔH° = 36.966 kJ/mol), entropy (ΔS° = 0.131 kJ/mol K), and activation energy (Ea) 40.208 kJ/mol of gentian violet adsorption. The negative ΔG° and positive ΔH° indicate that the overall adsorption is spontaneous and endothermic in nature.

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通过活性炭平衡、动力学和热力学研究去除水溶液中的龙胆紫

通过紫外-可见光谱研究了商业活性炭去除甲基玫瑰苯胺（龙胆紫、结晶紫）的定量动力学和平衡吸附参数。 比表面积为 1250 m2/g 的活性炭由 Brunauer, Emmett 表征et Teller (BET) 方法和零电荷点 pH (pzc)。两种活性炭对龙胆紫的吸附性能在可变搅拌速度 100–700 trs/min、吸附剂量 1–8 g/l、溶液 pH 1–14、初始龙胆紫浓度 5–15 mg/l、接触时间 0–50 分钟，温度 299–323 K，使用批处理模式操作找到最大吸附的最佳条件。使用拟一级、拟二级和Elovich动力学模型研究了龙胆紫的吸附机理。发现吸附动力学遵循准二级动力学模型，决定系数 (R2) 为 0.999。Weber-Morris 扩散模型适用于吸附机制。通过Langmuir、Freundlich、Elovich和Temkin模型分析了龙胆紫的平衡吸附数据。结果表明，Langmuir 模型提供了最佳相关性（在 26°C 和 40°C 下，qmax 分别为 22.727、32.258 mg/g）。不同温度下的吸附等温线已用于测定热力学参数，即自由能 (ΔG° = − 2.30 至 -5.34 kJ/mol)、焓 (ΔH° = 36.966 kJ/mol)、熵 (ΔS° = 0.131 kJ/mol K)，以及龙胆紫吸附的活化能(Ea) 40.208 kJ/mol。