PHOSPHORUS REMOVAL FROM WASTEWATER IN THE PRESENCE OF MESOPOROUS MATERIALS
Violeta Niculescu1*, Mihaela Iordache1, Marius Miricioiu1, Laurentiu Asimopolos2
1National Research and Development Institute for Cryogenics and Isotopic Technologies - ICSI Rm. Valcea, Uzinei Street no. 4, P.O. Box Râureni 7, 240050, Râmnicu Vâlcea, Romania 2Geological Institute of Romania, Caransebes Street, 1, Bucharest, 012271, Romania
ABSTRACT
Phosphorus constitutes an important element widely used in agriculture as a fertilizer and in industry as a detergent. The agricultural activities generate effluents rich in phosphorous compounds, which constitute a major concern due to their direct involvement in the eutrophication of the aquatic environments. Various Environmental Protection Agencies have identified eutrophication, resulting from excess phosphorus input, as the greatest threat to fresh water supply and leading to fish deaths and the degradation of habitat.
The elimination of phosphorus compounds from waste effluents are conventionally carried out by biological or physicochemical treatments which are long and complex to be operated, their efficiency in removing phosphate being influenced by several factors (pH, temperature, dissolved oxygen concentration, or the balance of the nutrients in water). A promising alternative for phosphorus compounds removal can be the adsorption process. Various adsorbents were developed and tested for phosphorous compounds removal, but their adsorption capacity is still low and the time to reach the equilibrium is relatively high.
Ordered mesoporous silica has proven to be good adsorbents for metal ions and amino acids, due to their high specific surface area, controlled pore diameters and controlled morphology. They are mechanically robust, non-toxic and environmentally friendly. Mesoporous materials have significant potential for use as adsorbents for removal of phosphate from water. In view of the above facts and in a continuous quest for high capacity, selective, effective and regenerable adsorbents, the present work is aimed to highlight the use of mesoporous materials for the removal of phosphorus compounds from wastewater. This paper reviews recent activities in the development of mesoporous materials as phosphate adsorbents. In particular, it mainly focuses on the synthesis, properties and phosphate removal efficiency of various materials with meso-porosity.
Keywords: Environment, mesoporous materials, phosphorus, wastewater.
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