Alum, also known as potassium aluminum sulfate, can be used to purify water. According to the Environmental Science Activities for the 21st Century Project, water purification is an essential sanitation measure taken to ensure drinking water is clean and safe. Novak and Watts point out that phosphorous is a common contaminant found in water supplies located near livestock shelter and grazing facilities. Alum in its powdered form can be added to water to bind with phosphorous particles to aid the water purification process.
How to Use Powdered Alum to Purify WaterBy Damien Thryn
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