en |
Simultaneous application of iron and aluminum anodes for nitrate removal: a comprehensive parametric study
Ghanbari, F.; Moradi, M.; Mohseni-Bandpei, A.; Gohari, F.; Mirtaleb Abkenar, T. & Aghayani, E.
Abstract
Exposure to high concentration of nitrate
through drinking water poses a threat to human health and
environment. Electrocoagulation (EC) is an alternative
water treatment process that involves electrogeneration of
coagulant agents. In the present study, EC was exerted for
the nitrate removal in a batch reactor using aluminum and
iron anodes simultaneously. The effects of the main
parameters including electrical current, initial pH, NaCl
dosage, initial nitrate concentration and presence of turbidity
on NO3
- removal were investigated. NO2
- as a byproduct
was monitored during electrolysis, and nitrate–
nitrite index was calculated. The results indicated that
optimum condition was pH of 5, 300 mA electrical current,
100 mg/L NaCl and electrolysis time of 40 min, under
which removal efficiency was 81.5 %. Nitrite anion was
generated during electrolysis of nitrate solution which
increases nitrate–nitrite index at the first reaction time, and
it was eliminated after 20-min electrolysis time. Reaction
kinetic of nitrate removal in the absence and presence of
turbidity was first-order and zero-order, respectively.
Keywords
Electrocoagulation; Nitrite; Turbidity effect; Al–Fe anodes
|