Using Recycled Concrete as an Adsorbent to Remove Phosphate from Polluted Water
Journal of Environmental Quality
|October 8, 2019
Summary
Seawater-modified waste concrete efficiently removes phosphate pollution. This sustainable method repurposes construction waste, offering a cost-effective solution for cleaner water. Calcium is key to phosphate adsorption.
Area of Science:
- Environmental Science
- Materials Science
- Water Treatment
Background:
- Phosphate pollution poses significant risks to aquatic and terrestrial ecosystems.
- Effective and economical methods for phosphate removal are crucial for environmental protection.
Purpose of the Study:
- To develop an economical and efficient method for phosphate adsorption using waste construction concrete modified with seawater.
- To investigate the phosphate adsorption capacity and removal efficiency of the modified material.
Main Methods:
- Waste construction concrete was modified using seawater.
- Phosphate adsorption experiments were conducted to evaluate the material's performance.
- Chemical and physical analyses were performed to understand the adsorption mechanism.
Main Results:
- Seawater-modified waste concrete exhibited highly efficient phosphate adsorption, particularly at low concentrations.
- Phosphate removal exceeded 90% across a broad pH range (3-11).
- Calcium (Ca) was identified as the primary element controlling phosphate uptake, with Ca and Magnesium (Mg) uniformly sequestered on the surface.
Conclusions:
- Seawater modification enhances the phosphate adsorption capacity of waste concrete.
- The modified material offers an efficient and sustainable solution for removing phosphate from polluted water.
- This approach effectively repurposes waste construction concrete, contributing to a circular economy.
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