Effect of extraction methods on mobilizable colloids and associated phosphorus from reservoir sediment
| Autor: | Marion Rabiet, Diep N. Nguyen, Véronique Deluchat, Malgorzata Grybos |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Geologic Sediments
endocrine system Environmental Engineering Health Toxicology and Mutagenesis Sonication 0208 environmental biotechnology chemistry.chemical_element 02 engineering and technology 010501 environmental sciences complex mixtures 01 natural sciences chemistry.chemical_compound Colloid Environmental Chemistry Colloids Dissolution 0105 earth and related environmental sciences Minerals Chemistry Phosphorus digestive oral and skin physiology Extraction (chemistry) Public Health Environmental and Occupational Health Sediment Sorption General Medicine General Chemistry Eutrophication Pollution 020801 environmental engineering body regions Environmental chemistry Hydroxide France Water Pollutants Chemical |
| Zdroj: | Chemosphere. 284:131321 |
| ISSN: | 0045-6535 |
| Popis: | Mobilizable colloids from reservoir sediment contain nutrients and contaminants, thus may affect water quality once being released. A major obstacle to evaluate the quantity and quality of mobilizable colloids in natural system is the using of appropriate method for colloid extraction from sediment and their separation from dissolved and particulate phases. This work evaluates the role of different extraction methods (agitation, sonication at sediment pH, and sonication at alkaline pH) on the characteristics (mass, size, shape and composition) of water-mobilizable colloids from sediment of Champsanglard dam reservoir (France). Attention has been paid to phosphorus (P), an important element in controlling eutrophication. Recovered colloids were highly affected on both quantity and quality according to the different applied protocols. The less aggressive agitation liberated low-energy water-dispersible colloids without physical damage and with less modification in colloidal chemical composition and shape, whereas sonication released 10–20 times higher colloid quantity but in lower size, due to physically disruption of fragile sediment structure or aggregated/chained colloids. In contrast, alkaline pH intensified colloid release by fortified repulsive forces between colloids and dissolution of organic coat. Concerning phosphorus, competition with hydroxide ions for sorption site or dissolution of phosphate minerals in alkaline pH caused release of dissolved P to solution and decrease of P content in recovered colloids. A special care should be paid to method selection according to the aim of the study and when comparing data from experiments conducted with different colloid extraction methods. |
| Databáze: | OpenAIRE |
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