The impact of various cations on the sorption of manganese in the thallus of freshwater algae spirogyra sp. and sea algae palmaria palmata

Abstract

Due to their occurrence in very different conditions and high resistance to physical and chemical factors, algae are pioneers colonising new environments and their sorption properties are used in biomonitoring and water remediation. The efficiency of the process of heavy metal sorption in algae used for in situ tests depends on abiotic factors, such as the chemical composition of water. Freshwater algae Spirogyra sp. were used in tests. Algae were exposed in the laboratory in manganese chloride solutions with various contents of other cations, including heavy metals and macronutrients. It has been shown that some heavy metals may desorb manganese bound to the surface of algae as a result of ion exchange in the following sequence: Cd 2+ < Mn 2+ ≈ Zn 2+ < Cu 2+ . It has been also found that the competitiveness of sorption of cations naturally present in the alga environment versus Mn 2+ cations changes in the sequence Na + < Ca 2+ < H + , defined for the concentrations referring to the cation unit charge. The results of tests were compared to the results of dried sea algae Palmaria palmata analyses.

Algae-Based Approach for Desalination: An Emerging Energy-Passive and Environmentally Friendly Desalination Technology

“…For the first step, salts in the bulk solution diffuse to the microalgae cell wall surface, and in the subsequent step, salts are deposited on the algae surface by different mechanisms, including ion exchange, microprecipitation, and complexation (coordination). , Ion exchange is considered an important mechanism for salt biosorption, as Na + can replace other cations bound to different functional groups on the algae surface. Rajfur and co-workers investigated the competitiveness of biosorption (adsorption) of different cations on the algae surface and suggested that Na + can replace Mn 2+ to be bound on the algae surface . It is worthwhile mentioning that the function of ion exchange is more related to the change of the ionic species rather than salt removal, except Na + and Cl – are replaced by H + and OH – , respectively.…”

“…Rajfur and co-workers investigated the competitiveness of biosorption (adsorption) of different cations on the algae surface and suggested that Na + can replace Mn 2+ to be bound on the algae surface. 58 It is worthwhile mentioning that the function of ion exchange is more related to the change of the ionic species rather than salt removal, except Na + and Cl − are replaced by H + and OH − , respectively. Microprecipitation occurs if the Na + solubility limit is reached.…”