OPTIMIZATIO OF ELECTROCHEMICAL PROCESS FOR REMOVING NITRATE FROM DRINKING WATER BY TAGUCHI MODEL

Contamination of water resources with nitrate as the primary contaminant is the most serious environmental problem in several rural regions worldwide. Consumption of undergrounddrinking water with nitrate concentration of 100-200 mg/l is considered as a general hygienic potentialrisk, especially in children, resulting in diseases such as blue baby syndrome. The aim of this appliedanalyticalstudy is to investigate nitrate removal from urban drinking water using batch reactorelectrochemical. Various operating variables were tested for their effects on nitrate removal; theseincluded current density, electrodes material, pH, and time. Nitrate removal efficiency is examined in different operating cases of the variables current density (1 to 8 mA/cm2), electrodes material(aluminium, copper, iron, steel, and zinc), pH (6 to 8), and time (5 to 40 min). Nitrate is determinedaccording to procedure detailed in standard methods. AS-AS as anode-cathode electrodes produce the mean of the lowest nitrate removal (0.1%), while Zn-Cu as anode-cathode electrodes produce themean of the highest nitrate removal (100%) at similar experimental conditions. Batch experimentsshowed that the maximum nitrate removal was obtained using zinc-copper as the anode-cathode electrode arrangement. The increase in current density from 1 to 8 mA / cm2 in at optimum electrode and pH increased nitrate removal from 62 to 100% (figure 2). The increase in time from 5 to 40 min atoptimum electrode and pH increased nitrate removal from 33 to 100%. The findings indicated that nitrate removal efficiency was increased with increasing current density, electrolysis time, and pH. The results of nitrate removal efficiency by Taguchi model showed that reaction time (42.6%) was themost important variable. Thus, batch experiments indicated that the electrochemical reactor could beefficient in removing nitrate from drinking water and may be considered as a promising technology for treating nitrate-polluted drinking water.

Keywords:

Drinking water , Electrochemical , Electrolysis , Nitrate , Taguchi