Electrocatalytic reduction of nitrate in water

Peel, JW; Reddy, KJ; Sullivan, BP; Bowen, JM

HERO ID

1654642

Reference Type

Journal Article

Year

2003

Language

English

PMID

12727264

HERO ID 1654642
In Press No
Year 2003
Title Electrocatalytic reduction of nitrate in water
Authors Peel, JW; Reddy, KJ; Sullivan, BP; Bowen, JM
Journal Water Research
Volume 37
Issue 10
Page Numbers 2512-2519
Abstract Nitrate (NO(3)(-)) contamination of groundwater is a common problem throughout intensive agricultural areas (nonpoint source pollution). Current processes (e.g., ion exchange, membrane separation) for NO(3)(-) removal have various disadvantages. The objective of this study was to evaluate an electrocatalytic reduction process to selectively remove NO(3)(-) from groundwater associated with small agricultural communities. A commercially available ELAT (E-Tek Inc., Natick, MA) carbon cloth with a 30% surface coated Rh (rhodium) (1microg x cm(-1)) was tested at an applied potential of -1.5 V versus standard calomel electrode (SCE) with a Pt auxiliary electrode. Electrocatalytic reduction process (electrolysis) of NO(3)(-) was tested with cyclic voltammetry (CV) in samples containing NO(3)(-) and 0.1M NaClO(4)(-). Nitrate and NO(2)(-) concentrations in test solutions and groundwater samples were analyzed by ion chromatography (IC). The presence of Rh on the carbon cloth surface resulted in current increase of 36% over uncoated carbon cloths. The electrocatalysis experiments using Rh coated carbon cloth resulted in reduction of NO(3)(-) and NO(2)(-) on a timescale of minutes. Nitrite is produced as a product, but is rapidly consumed upon further electrolysis. Field groundwater samples subjected to electrocatalysis experiments, without the addition of NaClO(4)(-) electrolyte, also exhibited removal of NO(3)(-) on a timescale of minutes. Overall, results suggest that at an applied potential of -1.5 V with respect to SCE, Rh coated carbon cloth can reduce NO(3)(-) concentrations in field groundwater samples from 73 to 39 mg/L (16.58 to 8.82 mg/L as N) on a timescale range of 40-60 min. The electrocatalytic reduction process described in this study may prove useful for removing NO(3)(-) and NO(2)(-) from groundwater associated with nonpoint source pollution.
Doi 10.1016/S0043-1354(03)00008-3
Pmid 12727264
Wosid WOS:000182940100031
Is Certified Translation No
Dupe Override No
Comments Source: Web of Science WOS:000182940100031
Is Public Yes
Language Text English
Keyword drinking water; chemical denitrification; rural communities; water quality; agriculture industry