Phosphorus removal from aqueous solution using iron coated natural and engineered sorbents
N Boujelben1, J Bouzid, Z Elouear
1Laboratoire Eau Energie et Environnement, département de génie géologique, Ecole Nationale d'Ingénieurs de Sfax, BP W 3038 Sfax, Tunisia. nesrine.boujelben@tunet.tn
Journal of Hazardous Materials
|July 6, 2007
Summary
Iron oxide-coated materials effectively remove phosphate ions from water. Iron-coated crushed brick shows the highest sorption capacity, offering a promising solution for industrial wastewater treatment.
Area of Science:
- Environmental Science
- Materials Science
- Water Treatment Technologies
Background:
- Industrial activities, particularly phosphate manufacturing in Sfax, Tunisia, cause significant water pollution.
- Phosphate pollution poses environmental risks, necessitating effective removal strategies.
- Metallic oxide-coated materials show potential as adsorbents for various pollutants.
Purpose of the Study:
- To evaluate the efficacy of three iron oxide-coated sorbent materials (synthetic coated sand, natural coated sand, and coated crushed brick) for phosphate ion removal from aqueous solutions.
- To characterize the surface properties and structure of the sorbent materials.
- To compare the phosphate sorption capacities of the different materials under varying conditions.
Main Methods:
- Sorbent materials (synthetic iron oxide coated sand (SCS), naturally iron oxide coated sand (NCS), and iron oxide coated crushed brick (CB)) were prepared and characterized using optical microscopy, scanning electron microscopy (SEM), infra-red spectroscopy, and X-ray diffraction.
- Batch experiments were conducted to investigate phosphate ion sorption from aqueous solutions.
- Sorption data were analyzed using Langmuir and Freundlich isotherms to determine adsorption capacities and mechanisms.
- The influence of pH and temperature on the sorption process was evaluated.
Main Results:
- Iron-coated crushed brick exhibited a higher surface area and more micropores due to its clay composition.
- The optimal pH for phosphate ion retention across all sorbents was determined to be 5.
- Phosphate sorption capacities at pH 5 were 1.5 mg/g for SCS, 1.8 mg/g for CB, and 0.88 mg/g for NCS.
- Adsorption was found to be an endothermic process for phosphate ion removal.
Conclusions:
- All tested iron oxide-coated materials, particularly iron-coated crushed brick, are effective for removing phosphate ions from water.
- These sorbents represent a viable emerging technology for industrial wastewater treatment with no adverse side effects.
- The study provides valuable data for developing sustainable water treatment solutions for phosphate-polluted environments.
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