Peroxymonosulfate-Co(II) oxidation system for the removal of the non-ionic surfactant Brij 35 from aqueous solution.
The non-ionic surfactant Brij 35 was effectively removed from concentrated aqueous solution by the peroxymonosulfate/Co(II) system, using oxone (2KHSO(5)·KHSO(4)·K(2)SO(4)) as a source of peroxymonosulfate. At pH=2.3 and initial Brij 35 concentration in the range 680-2410 mg L(-1), 86-94% removal was achieved after 24 h, using Co(II)=15 μM and oxone=5.9 mM. The effectiveness of removal did not change when initial pH was in the range 2.3-8.2. After five subsequent additions of Co(II) and oxone to the solution, COD and TOC removals increased up to 64% and 33%, respectively. Radical quenching tests confirmed that sulfate radical was the dominant radical species in the system. The main identified by-products from surfactant degradation were: (a) low molecular weight organic acids; (b) aldehydes and formates with shorter ethoxy chain than Brij 35; (c) alcohol ethoxylates carrying hydroxyl groups bonded to ethoxy chain. By-products identification allowed to hypothesize the pathways of Brij 35 degradation.
Consiglio Nazionale delle Ricerche, Istituto di Ricerca Sulle Acque, Sezione di Bari, Via Francesco De Blasio, 5, 70132 Bari, Italy.
Michele
M
Pagano
Angela
A
Volpe
Giuseppe
G
Mascolo
Antonio
A
Lopez
Vito
V
Locaputo
Ruggiero
R
Ciannarella
D003035:Cobalt / Q000737:chemistry*; D010084:Oxidation-Reduction; D010545:Peroxides / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000032:analysis / Q000737:chemistry*; D014865:Waste Disposal, Fluid / Q000379:methods; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D018508:Water Purification / Q000379:methods
D010545:Peroxides; D014874:Water Pollutants, Chemical; C038288:peroxymonosulfate; D003035:Cobalt; D011092:Polyethylene Glycols; C515901:Brij 35