SOME INFLUENCE FACTORS FOR NH4+ ADSORPTION ON WATER HYACINTH BIOCHAR (Eichhornia crassipes)

Abstract

The aim of this study is to evaluate the influence factors for the ammonium adsorption capacity on water hyacinth biochar such as solution pH, adsorbent dosage, reaction time and initial NH₄⁺ concentration. Water hyacinth biochar was produced by pyrolysis method (700 ^oC) by a kiln - VMF 165 with the nitrogen gas was pumped into the furnace at a rate of 3 L/min to remove air from the inside of the furnace. The oven temperature was then increased from room temperature to 700 °C at a heating rate of 10 °C/min. The treatments were randomly assigned and 3 replicates for each treatments. Research results were showed that pH_pzc of water hyacinth biochar was 10.1. Optimal adsorption pH value was 7; the optimal adsorbent dosage was 1g/50mL; the optimal reaction time was 120 minutes and the initial concentration of NH₄⁺ was 80 mg L^-1.