Department of Bioengineering, West Pomeranian University of Technology Szczecin, ul. J.Słowackiego 17, 71-434 Szczecin, Poland.
Molecules. 2020 Aug 31;25(17):3962. doi: 10.3390/molecules25173962.
Wastewater is characterized by a high content of phosphate and toxic metals. Many studies have confirmed the sorption affinity of alginate adsorbents for these ions. In this study, the adsorption of phosphate from effluent of sewage sludge on biodegradable alginate matrices cross-linked with Fe ions (Fe_Alg) was investigated. Kinetics and adsorption isotherms were tested in laboratory conditions in deionized water (DW_P) and in the effluent (SW_P), and in the same solutions enriched in toxic metals ions-Cu, Cd, Pb, and Zn (DW_PM and SW_PM). Batch experiments were performed by changing the concentration of phosphate at constant metal concentration. Kinetics experiments indicated that the pseudo-second-order model displayed the best correlation with adsorption kinetics data for both metals and phosphate. The Freundlich equation provided the best fit with the experimental results of phosphate adsorption from DW_P and DW_PM, while the adsorption from SD_P and SD_PM was better described by the Langmuir equation. For tested systems, the affinity of the Fe_Alg for metal ions was in the following decreasing order: Pb > Cu > Cd > Zn in DW_PM, and Pb > Cu > Cd > Zn in SW_PM. The metals' enrichment of the DW_P solution increased the affinity of Fe_Alg beads relating to phosphate, while the addition of the metals of the SW_P solution decreased this affinity.
污水具有高含量的磷酸盐和有毒金属。许多研究证实了海藻酸盐吸附剂对这些离子的吸附亲和力。在这项研究中，研究了可生物降解的海藻酸盐基质与 Fe 离子交联（Fe_Alg）对污水污泥废水中磷酸盐的吸附作用。在去离子水（DW_P）和废水中（SW_P）以及含有毒金属离子（Cu、Cd、Pb 和 Zn）的相同溶液中（DW_PM 和 SW_PM），在实验室条件下测试了动力学和吸附等温线。通过在恒定金属浓度下改变磷酸盐浓度进行批量实验。动力学实验表明，准二级模型与金属和磷酸盐的吸附动力学数据具有最佳相关性。对于从 DW_P 和 DW_PM 吸附磷酸盐的实验结果，Freundlich 方程提供了最佳拟合，而对于从 SD_P 和 SD_PM 吸附磷酸盐的实验结果，Langmuir 方程的拟合效果更好。对于测试的系统，Fe_Alg 对金属离子的亲和力顺序如下：在 DW_PM 中为 Pb>Cu>Cd>Zn，在 SW_PM 中为 Pb>Cu>Cd>Zn。DW_P 溶液中金属的富集增加了 Fe_Alg 珠与磷酸盐的亲和力，而 SW_P 溶液中金属的添加则降低了这种亲和力。
