Premium
Influence of Operating Conditions on Electrochemical Reduction of Nitrate in Groundwater
Author(s) -
Huang Wenli,
Li Miao,
Zhang Baogang,
Feng Chuanping,
Lei Xiaohui,
Xu Bin
Publication year - 2013
Publication title -
water environment research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.356
H-Index - 73
eISSN - 1554-7531
pISSN - 1061-4303
DOI - 10.2175/106143012x13418552642047
Subject(s) - nitrate , groundwater , environmental science , groundwater pollution , reduction (mathematics) , electrochemistry , environmental engineering , water pollution , chemistry , environmental chemistry , aquifer , engineering , mathematics , geotechnical engineering , electrode , organic chemistry , geometry
The influences of current density, initial pH, cation and anion concentrations, and the coexistence of Ca 2+ and HCO 3 − on the efficiency of electrochemical nitrate reduction by a copper cathode and Ti/IrO 2 anode in an undivided cell were studied. In the presence of 5 mM of sodium chloride (NaCl), the nitrate‐nitrogen concentration decreased from 3.57 to 0.69 mM in 120 minutes, and no ammonia or nitrite byproducts were detected. The nitrate reduction rate increased as the current density increased. The electrochemical method performed well at an initial pH range of 3.0 to 11.0. The rate of nitrate reduction increased as concentrations of Na + , K + , and Ca 2+ increased. The anion of the supporting electrolyte decreased the rate of reduction in the order Cl − > HCO 3 2‐ = CO 3 2‐ > SO 4 2‐ at both 5 mM and 10 mM of anion. The coexistence of Ca 2+ and HCO 3 − ions could inhibit nitrate reduction. The concentration of nitrate‐nitrogen in polluted groundwater decreased from 2.80 to 0.31 mM after electrolysis for 120 minutes.