title: Metal type and natural organic matter source for direct filtration electrocoagulation of drinking water.
abstract: Electrocoagulation (EC) was combined with immediate microfiltration as direct filtration electrocoagulation (DFEC) for dissolved organic carbon (DOC) removal in drinking water from synthetic and natural highly natural organic matter (NOM) impacted waters from three different sources: Suwannee River (Georgia, USA DOC(0)=13.79 mg/L), Nordic Reservoir (Vallsjøen, Norway DOC(0)=9.03 mg/L), and a natural source (Lost Lagoon, Vancouver, Canada DOC(0)=13.31 mg/L). Three anode materials were investigated: iron, aluminum, and zinc, in a batch EC process without rapid mixing, flocculation, or settling. Fifteen seconds of process time with the iron electrode (36 mg Fe/L) led to DOC removal of 44%. After 1 min of process time, DOC reduction was 65% (zinc)-73 (iron)%, with ~ 85% reduction (all metals) in UV-abs-254 (UV-abs-254 final=0.06 cm(-1)) for Suwannee NOM. Specific UV absorbance (SUVA-L/mgm) values decreased from 3.1 to 4.2 to under 2.0, indicating removal of high MW fractions of NOM. High performance size exclusion chromatography (HPSEC) fractionation supported SUVA results, showing reductions from 76% of DOC>1450 Da to approximately 40% after EC for all metals and Suwannee NOM. EC performed equally well for two different initial DOC concentrations of 13.79 and 21.59 mg/L DOC, showing 75% DOC and 89% UV-abs-254 reductions.
authors.affiliation: Department of Chemical & Biological Engineering, University of British Columbia 2360 East Mall, Vancouver, BC V6T 1Z3, Canada.
authors.forename: Kristian L
authors.initials: KL
authors.lastname: Dubrawski
authors.forename: Milena
authors.initials: M
authors.lastname: Fauvel
authors.forename: Madjid
authors.initials: M
authors.lastname: Mohseni
mesh_terms: D002254:Carbonates / Q000737:chemistry; D002712:Chlorides / Q000737:chemistry; D060766:Drinking Water; D004563:Electrochemistry; D005427:Flocculation; D006812:Humic Substances; D008670:Metals / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
chemical_list: D002254:Carbonates; D002712:Chlorides; D060766:Drinking Water; D006812:Humic Substances; D008670:Metals; D010710:Phosphates; D014874:Water Pollutants, Chemical