School of Resources Environmental and Chemical Engineering, Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, Nanchang University, Nanchang 330031, China E-mail:
School of Life Sciences, State Ministry of Education Key Laboratory of Poyang Lake Environment and Resource Utilization, Nanchang University, Nanchang 330031, China; † These authors contribute equally to this work.
Water Sci Technol. 2021 Mar;83(5):1183-1197. doi: 10.2166/wst.2021.041.
In this study, the polyethyleneimine (PEI) modified waste bamboo powder (WBP-Na-PEI) was successfully prepared and applied to adsorbing Congo red (CR) dye from aqueous solution. The obtained materials were characterized by field emission scanning electron microscope, X-ray diffraction, Fourier transform-infrared, and thermogravimetric analysis. The results showed that WBP-Na-PEI(1.8 K-5) was synthesized successfully and PEI uniformly covered the WBP-Na-PEI(1.8 K-5) surface. In the process of adsorption, four kinds of influencing factors were discussed, and the adsorption mechanisms such as kinetics, isotherm, thermodynamics were explored. The maximum adsorption capacity of WBP-Na-PEI(1.8 K-5) was 992.94 mg·g at 298 ± 1 K, and the removal efficiency was over 98%. Pseudo-first-order, pseudo-second-order and intra-particle diffusion models were studied, the results showed that the adsorption process conformed to the pseudo-second-order model, and the rate of this process was controlled by many steps. Furthermore, the removal efficiency of the adsorption kinetics reached 85% within 10 minutes. The results of the isotherm model and thermodynamics showed that the adsorption process was consistent with the Langmuir model and was mainly a spontaneous chemical endothermic process of monolayer. And the removal efficiency of the adsorbent reached 93% at the concentration of 400 mg/L, which can be expected to have a broad prospect in the treatment of CR industrial wastewater.
在这项研究中，成功制备了聚乙烯亚胺（PEI）改性废竹粉（WBP-Na-PEI），并将其应用于从水溶液中吸附刚果红（CR）染料。通过场发射扫描电子显微镜、X 射线衍射、傅里叶变换红外和热重分析对所得材料进行了表征。结果表明，成功合成了 WBP-Na-PEI（1.8 K-5），PEI 均匀覆盖在 WBP-Na-PEI（1.8 K-5）表面。在吸附过程中，讨论了四种影响因素，并探讨了动力学、等温线和热力学等吸附机制。在 298±1 K 下，WBP-Na-PEI（1.8 K-5）的最大吸附容量为 992.94mg·g-1，去除效率超过 98%。研究了伪一级、伪二级和内扩散模型，结果表明，吸附过程符合伪二级模型，该过程的速率受多个步骤控制。此外，吸附动力学的去除效率在 10 分钟内达到 85%。等温线和热力学模型的结果表明，吸附过程与 Langmuir 模型一致，主要是单层自发的化学吸热过程。吸附剂在 400mg/L 浓度下的去除效率达到 93%，有望在处理 CR 工业废水中具有广阔的前景。
