Research on preparation of modified bentonite and its removal of ammonia nitrogen and phosphorus from Wastewater

The experiment was orthogonal test by Na-bentonite as raw material, C₁₂ alkyl carbon chain length of the alkyl glucoside quaternary ammonium compound and AlCI₃ ·6H₂O as modifier, the index of ammonia and phosphorus removal rate. It is studied on main factors such as solvent / sodium bentonite ratio of L/s, the amount of aluminum modifier Al, the amount of organical modification Me and the modified temperature T. And removal of nitrogen and phosphorus from wastewater. The experimental study showed that (1) The removal of ammonia nitrogen and phosphorus is affected by dosage of Aluminum montmorillonite mostly, modification of temperature T secondly, solvent / sodium bentonite ratio of L/S and the dosage of organic modifier in the test of modified bentonite. (2)Modified bentonite is maintaining unchanged basic framework of Silicates, whose the layer spacing and cation exchange volume is bigger than sodium bentonite surface area is decreasing. Its characteristic absorption peak group is appeared in cationic surfactants. That proved modification of sodium bentonite is effective, the surface properties changed obviously and channels and gap structure improved. (3)The adsorption of nitrogen and phosphorus is a fast process by Modified bentonite , the equilibrium time was almost 60 min. The adsorption effect is influenced by modified bentonite dosage, reaction time, pH and other factors. The Freundlich model and the Langmuir model were both described the adsorption isotherm well.