Abstract

Physicochemical method was used to prepare lemongrass leaf activated carbon (LLAC) for removal of Remazol brilliant violet 5 R (RBV5R) dye from aqueous solutions. The surface area, mesopore surface area, total pore volume and average pore diameter of the LLAC are 836.04 m²/g, 598.6 04 m²/g, 0.472 04 cm³/g and 3.62 nm, respectively. The surface functional groups of LLAC before adsorption showed the existence of C–H, O–H, C-O, C = O, C = C, CH₃, N–O and C–N; they are significantly altered after adsorption. The equilibrium data were fitted into Freundlich, Langmuir, Dubinin Radushkevich, Temkin, Koble Corrigan, Vieth Sladek, Radke Prausnitz and Brouers Sotolongo isotherm models. The Koble Corrigan and Freundlich models gave the best fit judging from the correlation coefficient (R2). The monolayer adsorption capacities (qm) obtained for Langmuir and Koble Corrigan isotherm models are 125 and 342.9 mg/g respectively. Kinetic data were fitted using pseudo-first order, pseudo-second order, intraparticle diffusion, Elovich, Boyd and Avrami models respectively. Thermodynamic parameters (ΔS⁰, ΔH⁰and ΔG⁰) were estimated. The mean adsorption energy E_a was 2.811 kJ/mol signifying that the adsorption is physically controlled. This study revealed that lemongrass leaf is effective in removing RBV5R dye from aqueous systems.

摘要

采用物化法制备柠檬草叶活性炭 (LLAC)，用于去除水溶液中的 Remazol 亮紫 5 R (RBV5R) 染料。LLAC的比表面积、中孔比表面积、总孔容和平均孔径分别为836.04 m ² /g、598.6 04 m ² /g、0.472 04 cm ³ /g和3.62 nm。LLAC吸附前的表面官能团表明存在C-H、O-H、CO、C=O、C=C、CH ₃, N–O 和 C–N; 它们在吸附后发生了显着变化。将平衡数据拟合到 Freundlich、Langmuir、Dubinin Radushkevich、Temkin、Koble Corrigan、Vieth Sladek、Radke Prausnitz 和 Brouers Sotolongo 等温线模型中。从相关系数 (R2) 判断，Koble Corrigan 和 Freundlich 模型给出了最佳拟合。Langmuir 和 Koble Corrigan 等温线模型获得的单层吸附容量 (qm) 分别为 125 和 342.9 mg/g。动力学数据分别使用伪一级、伪二级、粒子内扩散、Elovich、Boyd 和 Avrami 模型进行拟合。估计了热力学参数（ΔS ⁰、ΔH ⁰和ΔG ^{0 ）。}平均吸附能 E _a为 2.811 kJ/mol，表明吸附是物理控制的。这项研究表明，柠檬草叶可有效去除水系统中的 RBV5R 染料。