This research demonstrates that cerium is a highly efficient and sustainable alternative to traditional coagulants for phosphorus removal in wastewater, achieving up to 98.9% removal at lower dosages while remaining effective across a wide pH range.
Water pollution is a growing concern, and phosphorus is one of the main culprits behind harmful algal blooms and eutrophication in lakes and rivers. Traditional wastewater treatment methods use aluminum-based coagulants to remove phosphorus, but these methods come with limitations—high chemical demand, pH sensitivity, and excessive sludge production.
Enter cerium, a rare-earth element that’s proving to be a game-changer in wastewater treatment! 🌍✨
Phosphorus is essential for plant growth, but when too much of it enters water bodies, it leads to excessive algae growth. This process, called eutrophication, depletes oxygen in water, harming aquatic life and affecting water quality. That’s why removing phosphorus from wastewater is crucial before it reaches natural ecosystems.
Coagulation is a key step in wastewater treatment that helps remove suspended particles and dissolved nutrients. Traditional coagulants like aluminum sulfate (alum) work by binding to phosphorus, forming particles that settle out of the water. However, alum has some drawbacks:
❌ Requires high dosages 🔢
❌ Lowers pH, requiring extra chemical adjustments ⚖️
❌ Produces large amounts of sludge 🏭
Recent research highlights that cerium chloride is a more efficient and cost-effective coagulant for phosphorus removal. Compared to alum, cerium:
✔️ Removes up to 98.9% of phosphorus at lower dosages 🌱
✔️ Works across a wider pH range, reducing the need for pH adjustments ⚖️
✔️ Produces a more stable and crystalline phosphorus precipitate 🔬
✔️ Also removes up to 27.9% of organic matter (COD) for better water quality 🌊
When cerium is added to wastewater, it reacts with phosphorus to form cerium phosphate (CePO4), an insoluble, stable compound that can be easily removed. Unlike aluminum-based coagulants, cerium maintains its efficiency regardless of pH fluctuations, making it a more reliable option for wastewater treatment plants.
✅ Lower Dosages, Higher Efficiency: While alum requires 5 mg of Al per mg of phosphorus, cerium achieves better results with just 1.5 mg of Ce per mg of phosphorus.
✅ Works at Any pH: Cerium removes phosphorus efficiently across a pH range of 3 to 10, whereas alum’s efficiency declines at low pH levels.
✅ Reduces Organic Pollution: Cerium also helps reduce chemical oxygen demand (COD), improving overall water quality.
✅ Stable Precipitate Formation: The cerium phosphate formed is 94% pure, making it a potentially reusable byproduct for agricultural fertilizers! 🌾
The use of cerium in wastewater treatment presents a greener, more sustainable approach to phosphorus removal. Some exciting possibilities for the future include:
🔹 Recovering cerium phosphate for agricultural use as a phosphorus-rich fertilizer. 🌿
🔹 Reducing sludge production, making wastewater treatment plants more efficient. 🚰
🔹 Expanding applications beyond municipal wastewater treatment, such as industrial effluent treatment. 🏭
The research is clear—cerium offers a better, cleaner, and more efficient way to tackle phosphorus pollution in wastewater. As we seek innovative solutions for environmental challenges, rare-earth elements like cerium could play a vital role in creating a more sustainable future for water management. 🌊💙
🔹 Phosphorus (P) – A nutrient essential for plant growth, but too much of it in water leads to harmful algal blooms. 🌱💧 - This concept has also been explored in the article "Transforming Waste into Growth: How Deinking Paper Sludge Powers Sustainable Farming 🌱📜".
🔹 Eutrophication – When excess nutrients (like phosphorus) cause rapid algae growth, depleting oxygen and harming aquatic life. 🦠➡️🐟💀
🔹 Coagulation – A process in wastewater treatment where chemicals help clump tiny particles together so they can be removed. 🌀💦
🔹 Cerium (Ce) – A rare-earth element that binds with phosphorus to form a solid compound, making it easy to filter out. ✨🔬
🔹 Alum (Aluminum Sulfate, Al₂(SO₄)₃) – A traditional coagulant used for phosphorus removal, but it has downsides like high dosage needs and pH sensitivity. 🏭⚖️
🔹 Chemical Oxygen Demand (COD) – A measure of the organic pollutants in water; lower COD means cleaner water. 🌊✅ - This concept has also been explored in the article "🌺 From Waste to Wonderful: Ornamental Plants Clean Up Rural Wastewater".
Source: Osra, F.A. Cerium as an Efficient Coagulant for Phosphorus Removal from Wastewater. Sustainability 2025, 17, 1862. https://doi.org/10.3390/su17051862
From: Umm-Alqura University.
