Premium
A Hybrid Approach: Indirect Electro‐Oxidation Followed by In Situ Electrogeneration of H 2 O 2 in Real Textile Effluent
Author(s) -
Aravind Priyadharshini,
Selvaraj Rajeswari,
Sankarmahalingam Angappan,
Kandasamy Subramanian
Publication year - 2016
Publication title -
clean – soil, air, water
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.444
H-Index - 66
eISSN - 1863-0669
pISSN - 1863-0650
DOI - 10.1002/clen.201400673
Subject(s) - effluent , chemistry , sulfuric acid , electrochemistry , cyclic voltammetry , chlorine , nuclear chemistry , degradation (telecommunications) , chemical oxygen demand , fourier transform infrared spectroscopy , inorganic chemistry , cathode , electrode , waste management , chemical engineering , organic chemistry , sewage treatment , engineering , telecommunications , computer science
A two‐step treatment process has been investigated for effective textile effluent management. In step I, the effluent was decolorized via chlorine‐mediated indirect electrooxidation (InDEO), while H 2 O 2 was electrogenerated during step II in the decolorized textile effluent, by employing an H‐type divided electrochemical cell. The native salts present within the decolorized textile effluent (9.4 g/L Na 2 SO 4 and 0.8 g/L NaCl) were exploited as electrolytes for the catholyte, whereas 0.5 N sulfuric acid was used as the anolyte for the in situ electrochemical generation of H 2 O 2 . During the cyclic voltammetry tests, O 2 reduction at the activated carbon felt cathode was observed around –0.86 V versus saturated calomel electrode (SCE) at a scan rate of 100 mV/s. Under optimized conditions (cathode potential of –0.9 V vs. SCE and catholyte at pH 6) about 1.45 ± 0.01 mM H 2 O 2 have been generated. The effluent containing H 2 O 2 was subjected to Fenton reaction and the generation of OH • radicals was confirmed by electron paramagnetic resonance spectroscopy. The results indicated a 59% reduction of the chemical oxygen demand; significant modifications of the functional groups were observed by Fourier transform IR spectroscopy. High performance LC analysis confirmed the degradation of the organic compounds during the oxidative treatment process. These findings suggest the application of this method for degradation of highly colored textile effluents.