Li Cui, You EnDe, Ci Jia Xiang, Huang Qin, Zhao Yong Sheng, Li Wen Zhong, Yan Yu Cheng, Zuo Zhuo
The Engineering and Technical College of Chengdu University of Technology, Leshan614000, China.
Southwestern Institute of Physics, Chengdu610225, China.
ACS Omega. 2024 May 22;9(22):23688-23702. doi: 10.1021/acsomega.4c01417. eCollection 2024 Jun 4.
In China, both vanadium(V) and chromium(VI) are present in wastewater resulting from vanadate precipitation (AVP wastewater) and from leaching vanadium-chromium reduction slag. Addressing environmental preservation and the comprehensive utilization of metal resources necessitates the extraction and separation of V(V) and Cr(VI) from these mixed solutions. However, their separation is complicated by very similar physicochemical properties. This study establishes a method for the dynamic selective adsorption of V(V) from such mixtures. It evaluates the impact of various operating conditions in columns on dynamic adsorption behavior. This study examines the migration patterns of the mass transfer zone (MTZ) and forecasts its effective adsorption capacity through multivariate polynomial regression and a neural network (NN) model. The NN model's outcomes are notably more precise. Its analysis reveals that is the most critical factor, with Q and H following in importance. Furthermore, the dynamic properties were analyzed using two established models, Thomas and Klinkenberg, revealing that both intraparticle and liquid film diffusion influence the rates of exchange adsorption, with intraparticle diffusion being the more significant factor. Using 3 wt % sodium hydroxide as the eluent to elute V(V)-loaded resin at a flow rate of 4 mL/min resulted in a chromium concentration of less than 3 mg/L in the V(V) eluate, indicating high vanadium-chromium separation efficiency in this method. These findings offer theoretical insights and economic analysis data that are crucial for optimizing column operation processes.
在中国，钒（V）和铬（VI）都存在于钒酸盐沉淀产生的废水（AVP废水）以及钒铬还原渣浸出液中。为了保护环境和综合利用金属资源，必须从这些混合溶液中提取和分离V（V）和Cr（VI）。然而，它们非常相似的物理化学性质使分离变得复杂。本研究建立了一种从此类混合物中动态选择性吸附V（V）的方法。评估了柱中各种操作条件对动态吸附行为的影响。本研究考察了传质区（MTZ）的迁移模式，并通过多元多项式回归和神经网络（NN）模型预测其有效吸附容量。NN模型的结果明显更精确。分析表明，[此处原文缺失相关内容]是最关键的因素，其次是Q和H。此外，使用托马斯和克林肯伯格这两个已建立的模型对动态特性进行分析，结果表明颗粒内扩散和液膜扩散都影响交换吸附速率，其中颗粒内扩散是更重要的因素。以3 wt%的氢氧化钠为洗脱剂，以4 mL/min的流速洗脱负载V（V）的树脂，V（V）洗脱液中的铬浓度低于3 mg/L，表明该方法具有较高的钒铬分离效率。这些发现为优化柱操作工艺提供了至关重要的理论见解和经济分析数据。
