Mechanism of calcium hydroxide-reinforced magnesium-loaded clinoptilolite/phosphoric acid-modified biochar for NH₃-N removal from rare earth element tailing wastewater

An efficient composite for NH 3 -N removal from REE wastewater was developed, removing NH 3 -N primarily by forming calcium magnesium ammonium phosphate precipitation along with volatilization, adsorption, and struvite precipitation.