Carreira Ana R F, Veloso Telma, Macário Inês P E, Pereira Joana L, Ventura Sónia P M, Passos Helena, Coutinho João A P
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal.
CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193, Aveiro, Portugal; Department of Biology & CESAM, University of Aveiro, Aveiro, Portugal.
Chemosphere. 2023 Feb;314:137675. doi: 10.1016/j.chemosphere.2022.137675. Epub 2022 Dec 29.
The use of macroalgae, microalgae and cyanobacteria for metal sorption has been widely reported. Still, there are no studies allowing a direct comparison of the performance of these biomasses, especially while evaluating metal competition. The simultaneous sorption of Co, Cu, Ni and Zn present in a multi-elemental solution by six macroalgae, two microalgae and three cyanobacteria was evaluated. Brown macroalgae were shown to be the most promising biosorbent, with Undaria pinnatifida having a total metal sorption capacity of 0.6 mmol g. Overall, macroalgae performed better than microalgae, followed by cyanobacteria. Carboxyl groups were identified as being the main functional groups involved in metal sorption, and all biomass samples were found to be selective to Cu. This was linked not only to its higher complexation constant value with relevant functional groups when compared to the remaining metals, but also the Irving-Williams series. The release of K and Ca to the aqueous solution during the metal sorption was followed. The obtained results suggest they are readily exchanged with metals in the solution, indicating the occurrence of an ion-exchange mechanism in metal sorption by most biomass. Red macroalgae are an exception to the reported trends, suggesting that their metal sorption mechanism may differ from the other biomass types.
利用大型藻类、微藻和蓝细菌进行金属吸附的研究已有广泛报道。然而，尚无研究能够直接比较这些生物质的性能，尤其是在评估金属竞争时。本研究评估了六种大型藻类、两种微藻和三种蓝细菌对多元素溶液中钴、铜、镍和锌的同时吸附情况。结果表明，褐藻是最具潜力的生物吸附剂，其中裙带菜的总金属吸附量为0.6 mmol/g。总体而言，大型藻类的吸附性能优于微藻，其次是蓝细菌。羧基被确定为参与金属吸附的主要官能团，并且发现所有生物质样品对铜具有选择性。这不仅与其与相关官能团的络合常数高于其他金属有关，还与欧文-威廉姆斯序列有关。研究了金属吸附过程中钾和钙向水溶液中的释放情况。所得结果表明，它们很容易与溶液中的金属发生交换，这表明大多数生物质在金属吸附过程中存在离子交换机制。红藻是所报道趋势的一个例外，这表明它们的金属吸附机制可能与其他生物质类型不同。
