Chemical Engineering Department, Federal University of Santa Maria-UFSM, 1000, Roraima Avenue, Santa Maria, RS, 97105-900, Brazil.
Sanitary and Environmental Engineering Department, Federal University of Santa Maria, Santa Maria, 97105-900, Brazil.
Environ Sci Pollut Res Int. 2020 Jul;27(20):25727-25739. doi: 10.1007/s11356-020-08854-6. Epub 2020 Apr 30.
The Ocotea puberula bark powder (OPBP) was evaluated as an effective adsorbent for the removal of crystal violet (CV) from colored effluents. OPBP was characterized and presented a surface with large cavities, organized as a honeycomb. The main functional groups of OPBP were O-H, N-H, C=O, and C-O-C. The adsorption of CV on OPBP was favorable at pH 9 with a dosage of 0.75 g L. The Avrami model was the most suitable to represent the adsorption kinetic profile, being the estimated equilibrium concentration value of 3.37 mg L for an initial concentration of 50 mg L (CV removal of 93.3%). The equilibrium was reached within 90 min. The data were better described by the Langmuir isotherm, reaching a maximum adsorption capacity of 444.34 mg g at 328 K. The Gibbs free energy ranged from - 26.3554 to - 27.8055 kJ mol, and the enthalpy variation was - 11.1519 kJ mol. The external mass transfer was the rate-limiting step, with Biot numbers ranging from 0.0011 to 0.25. Lastly, OPBP application for the treatment of two different simulated effluents was effective, achieving a removal percentage of 90%.
奥克泰阿蒲桃树皮粉（OPBP）被评估为一种从有色废水中去除结晶紫（CV）的有效吸附剂。OPBP 进行了特征描述，其表面具有大空腔，呈蜂窝状组织。OPBP 的主要官能团为 O-H、N-H、C=O 和 C-O-C。在 pH 9 时，OPBP 对 CV 的吸附效果较好，投加量为 0.75 g·L。Avrami 模型最适合表示吸附动力学曲线，在初始浓度为 50 mg·L 时，估计的平衡浓度值为 3.37 mg·L（CV 去除率为 93.3%）。90 min 内达到平衡。数据更符合 Langmuir 等温线，在 328 K 时达到最大吸附容量 444.34 mg·g。吉布斯自由能范围为-26.3554 至-27.8055 kJ·mol，焓变值为-11.1519 kJ·mol。外部传质是限速步骤，Biot 数范围为 0.0011 至 0.25。最后，OPBP 应用于两种不同模拟废水的处理均有效，去除率达到 90%。
