Nitrogen removal from groundwater using scoria: Kinetics, equilibria and microstructure.

In this study the novel use of scoria to remove ammonia nitrogen, nitrite nitrogen, and nitrate nitrogen from groundwater. The experiments were conducted on connect time, kinetics studies, adsorption isotherms, effect of pH and microstructure, so that the characteristics of removal were studied. The kinetics followed the pseudo-second order model. The rate of ammonia nitrogen adsorption was mainly controlled by intramolecular proliferation. The adsorption process for nitrite nitrogen and nitrate nitrogen was divided into the boundary layer diffusion and intramolecular proliferation. The isotherm data closely fitted the Langmuir isotherm models. Scoria is a mesoporous material whose cylindrical-shaped pores are dominating in microstructure. Overall, scoria was found to be an effective material for nitrogen purification of groundwater.