[Study of nitrate removal from water resources using magnesium powder]

ABSTRACT

Nowadays nitrate concentrations in surface water and especially in groundwater have increased in many locations in the world. Since nitrates cause many health and environmental concerns, increased nitrate concentrations in groundwater have led to rendered aquifers unusable as water sources. So, as the water demand is still increasing the throughout the world, decreasing the nitrate concentration in drinking water is imperative. Magnesium powder has been determined to be potentially useful for the removal of nitrate in the water environment. This research is aimed at subjecting the kinetics of nitrate chemical reduction by Mg[0] to an analysis of some factors affecting the chemical denitrification. Nitrate concentrations determined in 220 nm using a spectrophotometer. To determine the performance of nitrate removal by Mg[0] powder, double distilled water was used for preparation of reagents and simulation of contaminated water with nitrate.All experiments were triplicate and the averaged results were reported. Kinetics analysis from batch studies revealed that the denitrification reaction with Mg[0] powder appeared to be a first-order with respect to substrate and the observed reaction rate constant [k[obs]]. The effects of mixing intensity on the denitrification rate suggest that the denitrification appears to be coupled with oxidative dissolution of magnesium through a largely mass transportlimited surface reaction. Also in the denitrification by Mg[0] determined that Mg[0] dose related with kobs[R[2]>0/99]S In this research was determined that denitrification effectively by Mg[0] powder can achieved in a wide range of concentrations under atmospheric conditions and without pH controlling within short reaction time. Denitrification rate was related to some parameters such as contact time, Mg[0] dosage, mixing rate and initial nitrate concentration