Valorization and Evaluation of Terminalia Ivorensis Fibrous Waste for Its Environmental Sequestration Potential for Industrial Anionic Dyes in Aqua System

ABSTRACT

This research depicts the pragmatic sequestration capacity of ubiquitous Terminalia ivorensis tree bark (TITB) on toxic anionic dyes (congo red (CR), methyl orange (MO), chlorophenol red (CPR), and Eosin Y (EY)) from aqua system. Surface characterization of TITB by bulk density, Boehm titration, pH of point of zero charge (pH_PZC), field emission-scanning electron microscopy (FE-SEM) and Fourier transform infrared (FTIR) spectroscopy revealed that TITB comprise rough intertwined texture with some functional moieties which adsorbed the industrial dyes. The adsorption capacities ($q_e$) of MO, CR, and EY were maximum at pH 2.0 ($q_e$= 84.59, 92.67 and 92 mg.g⁻¹ respectively) while that of CPR was maximum at pH 6.0 ($q_e$= 99.05 mg.g⁻¹). Langmuir monolayer coverage capacity ($q_{max}$) of TITB was obtained for the adsorption of EY, which was 142.45 mg.g⁻¹. Adsorption kinetics conformed to pseudo-second order kinetic model with a rate constant, $k_2$ ≤ 0.9702 min⁻¹. The change in Gibbs free energy (ΔG°) for the adsorption process was found to be negative showing that the maximum adsorption was spontaneous at operational temperatures for all dyes. Enthalpy and entropy change (∆H° and ∆S°) were positive for CR, MB, and EY describing endothermic form and increased disorderliness between the adsorbent-dye interface.

摘要

本研究描述了无处不在的紫罗兰树皮（TITB）对水中有毒阴离子染料刚果红（CR）、甲基橙（MO）、氯酚红（CPR）和曙红Y（EY）的实际吸附能力. 通过堆积密度、Boehm滴定、零电荷点pH值（pHPZC）、场发射扫描电子显微镜（FE-SEM）和傅立叶变换红外光谱（FTIR）等方法对其进行了表面表征，结果表明，TITB具有粗糙的缠结结构，其中一些官能团吸附了工业染料. MO、CR和EY的吸附容量（）在pH 2.0时最大（分别为84.59、92.67和92mg.g-1），CPR在pH 6.0时最大（99.05mg.g-1）. 用Langmuir单分子膜覆盖容量（）法测定了TITB对EY的吸附量，为142.45mg.g-1. 吸附动力学符合准二级动力学模型，具有速率常数，≤ 0.9702分钟-1. 吉布斯自由能的变化(ΔG°) 因为吸附过程是负的，表明所有染料在工作温度下的吸附都是自发的. 焓和熵变(∆H° 以及∆S°) CR、MB和EY呈阳性，说明吸附剂-染料界面的吸热形式和无序性增加.

KEYWORDS:

• 关键词
• 铁线蕨树皮
• 吸附
• 阴离子染料
• 紫茎泽兰
• 动力学
• 平衡

KEYWORDS:

• Teminalia ivorensis tree bark
• adsorption
• anionic dyes
• terminalia ivorensis
• kinetics
• equilibrium

Acknowledgments

Not applicable

Conflicts of interest

The authors declare that there is no conflict of interest in this research work.

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