Ganesan Janet Joshiba, Chien Chia-Shang Chang, Kumar P Senthil, Sundaram Hemavathi, Thangappan Hariharan, Achuthan Aravindan, Rajamanickam Sivarethinamohan, Rangasamy Gayathri
Railway Technical Centre, National Kaohsiung University of Science and Technology, No 1, University Road, Yanchao District, Kaohsiung City, 82445, Taiwan (ROC).
Department of Construction Engineering, National Kaohsiung University of Science and Technology, No 1, University Road, Yanchao District, Kaohsiung City, 82445, Taiwan (ROC).
Environ Geochem Health. 2024 Jul 13;46(9):308. doi: 10.1007/s10653-024-02093-1.
This study introduces a new biosorbent derived from Delonix regia bark-activated carbon to efficiently remove Chromium Cr(VI) metal ions from aqueous systems. The biosorbent was synthesized from the bark powder of the plant species and chemically activated with phosphoric acid. The biosorbent was characterized using FTIR, SEM, and BET to determine its functional properties and structural morphology. The batch adsorption experiments examined the optimal conditions for Cr(VI) metal ion adsorption, identifying that the highest removal efficiency occurred at pH levels of 2. The ideal adsorbent dosage was determined to be 2.5 g/L, with equilibrium achieved at a contact time of 60 min at the optimal temperature of about 303 K for a Cr(VI) metal ion concentration of 20 mg/L. Various isotherm models were applied to the adsorption equilibrium values, revealing that the adsorbent had a maximum removal capacity of approximately 224.8 mg/g for Cr(VI) metal ions. The adsorption process of Cr(VI) on the DAC biosorbent was best described by the Freundlich isotherm, indicating multilayer adsorption. The kinetic data fit well with the pseudo-second-order model. Thermodynamic parameters suggested that the adsorption process was spontaneous, exothermic, and feasible across different temperatures. Furthermore, the desorption studies showed that the DAC biosorbent can easily be rejuvenated and utilized several cycles with high adsorption capacity. These findings indicate that the developed adsorbent is environmentally friendly and effective for removing Cr(VI) from water systems.
本研究介绍了一种源自凤凰木树皮活性炭的新型生物吸附剂，用于从水体系中高效去除铬（Cr(VI)）金属离子。该生物吸附剂由该植物物种的树皮粉末合成，并用磷酸进行化学活化。使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和比表面积分析仪（BET）对生物吸附剂进行表征，以确定其功能特性和结构形态。批量吸附实验考察了Cr(VI)金属离子吸附的最佳条件，确定在pH值为2时去除效率最高。理想的吸附剂用量确定为2.5 g/L，对于20 mg/L的Cr(VI)金属离子浓度，在约303 K的最佳温度下接触60分钟达到平衡。将各种等温线模型应用于吸附平衡值，结果表明该吸附剂对Cr(VI)金属离子的最大去除容量约为224.8 mg/g。Cr(VI)在DAC生物吸附剂上的吸附过程最符合弗伦德利希等温线，表明为多层吸附。动力学数据与伪二级模型拟合良好。热力学参数表明吸附过程是自发的、放热的，并且在不同温度下都是可行的。此外，解吸研究表明，DAC生物吸附剂可以很容易地再生，并能以高吸附容量使用多个循环。这些发现表明，所开发的吸附剂对从水体系中去除Cr(VI)具有环境友好性且有效。
