Process Optimization of Electrochemical Oxidation of Ammonia to Nitrogen for Actual Dyeing Wastewater Treatment.
Int J Environ Res Public Health
; 16(16)2019 08 15.
Article
em En
| MEDLINE
| ID: mdl-31443230
ABSTRACT
To mitigate the potential environmental risks caused by nitrogen compounds from industrial wastewater, residual ammonia after conventional wastewater treatment should be further eliminated. In this work, an electrochemical oxidation process for converting ammonia to nitrogen in actual dyeing wastewater was investigated. The effects of the main operating parameters, including initial pH value, applied current density, NaCl concentration, and flow, were investigated on ammonia removal and products distribution. Experimental results indicated that, under optimal conditions of an initial pH value of 8.3, applied current density of 20 mA cm-2, NaCl concentration of 1.0 g L-1, and flow of 300 mL min-1, the ammonia could be completely removed with N2 selectivity of 88.3% in 60 min electrolysis. A kinetics investigation using a pseudo-first-order model provided a precise description of ammonia removal during the electro-oxidation process. Experimental functions for describing the relationships between kinetic constants of ammonia removal and main operating parameters were also discussed. Additionally, the mechanisms and economic evaluation of ammonia oxidation were conducted. All these results clearly proved that this electro-oxidation process could efficiently remove ammonia and achieve high N2 selectivity.
Palavras-chave
Texto completo:
1
Temas:
ECOS
/
Avaliacao_economica
Bases de dados:
MEDLINE
Assunto principal:
Poluentes Químicos da Água
/
Eliminação de Resíduos Líquidos
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Corantes
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Eletrólise
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Águas Residuárias
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Amônia
/
Nitrogênio
Idioma:
En
Revista:
Int J Environ Res Public Health
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
China