Treatment of humic acids with ferric, aluminum, and chromium ions in water

Combined effects of pH, hardness and dissolved organic carbon on acute metal toxicity to Daphnia magna

“…Contrary to Cu(II) toxicity, Cr(VI) toxicity was not influenced by DOC concentration. Kaczynski and Kieber [7] reported that organic matter complexation with chromium was insignificant, and Kislenko and Oliynyk [8] also showed that chromium was hardly bound with humic acid at pH values higher than 4.…”

“…To account for their risks to human and the environment, many researchers have evaluated biological toxicity of copper and chromium in both synthetic and industrial wastewaters [5][6][7][8][9]. Although it is well known that metal toxicity is affected by water quality parameters, such as pH, dissolved organic carbon (DOC) and hardness, studies on their combined effects are limited [10].…”

Effects of surfactants on the adsorptive removal of basic dyes from water using an organomineral sorbent—iron humate

“…HAs are insoluble in neutral and acidic media and can be used as sorbents for wastewater treatment (typically for removing heavy metals) [19,20]. More advantageous, however, seems to be an application of the salts of HAs with polyvalent metal cations (metal humates) that are markedly less soluble in aqueous solutions due to "crosslinking" and aggregation [21][22][23][24].…”

Humic Acids Affect the Detection of Metal Ions by Cyanobacteria Carbon Quantum Dots Differently

“…When CQDs are applied to detect metal ions in natural environments, coexisting dissolved organic matter provides one of the main interferences since it can combine with metal ions or CQDs [ 23 , 24 ]. For example, humic acids (HAs), one of the main components of dissolved organic matter, could combine with Fe 3+ via strong chemical bonds [ 25 ]. A large number of groups such as –OH and –C=O contained in the HAs facilitate their complex physicochemical interactions with other coexisted ions [ 25 , 26 ].…”

“…For example, humic acids (HAs), one of the main components of dissolved organic matter, could combine with Fe 3+ via strong chemical bonds [ 25 ]. A large number of groups such as –OH and –C=O contained in the HAs facilitate their complex physicochemical interactions with other coexisted ions [ 25 , 26 ]. Moreover, HAs can also produce FL under specific excitation conditions [ 27 ], which may overlap with that of CQDs or metal ions in a wide spectral range.…”