title: Harvesting of microalgae cell using oxidized dye wastewater.
abstract: In this study, oxidized dye wastewaters were tested for their potential to be used as a cheap coagulant for microalgae harvesting. Two dyes (methylene blue (MB) and methyl orange (MO)) were selected as model dyes, and the Fenton-like reaction under high temperature (90 °C, 1 min) employed as an oxidative treatment option. A maximum harvesting efficiency over 90% was obtained with both MB and MO at a dilution ratio of 5:1 (dye wastewater: cell culture), when the optimal oxidation condition was 20 mg/L of dye, 1 mM of FeCl3, and 0.5% of H2O2 concentration. This phenomenon could be explained by the possibility that amine groups are formed and exposed in oxidized dyes, which act as a kind of amine-based coagulant just like chitosan. This study clearly showed that dye wastewater, when properly oxidized, could serve as a potent coagulant for microalgae harvesting, potentially rendering the harvesting cost reduced to a substantial degree.
authors.affiliation: Department of Civil and Environmental Engineering, KAIST, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Yeong Hwan
authors.initials: YH
authors.lastname: Seo
authors.affiliation: Department of Civil and Environmental Engineering, KAIST, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Doyoung
authors.initials: D
authors.lastname: Park
authors.affiliation: Clean Fuel Department, Korea Institute of Energy Research, 152 Gajeong-ro, Yuseong-gu, Daejeon 305-343, Republic of Korea.
authors.forename: You-Kwan
authors.initials: YK
authors.lastname: Oh
authors.affiliation: Department of Civil and Environmental Engineering, KAIST, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea.
authors.forename: Sukhwan
authors.initials: S
authors.lastname: Yoon
authors.affiliation: Department of Civil and Environmental Engineering, KAIST, 373-1, Guseong-dong, Yuseong-gu, Daejeon 305-701, Republic of Korea. Electronic address: hanj2@kaist.ac.kr.
authors.forename: Jong-In
authors.initials: JI
authors.lastname: Han
mesh_terms: D001391:Azo Compounds / Q000737:chemistry*; D061249:Batch Cell Culture Techniques / Q000379:methods; D002469:Cell Separation / Q000379:methods*; D004396:Coloring Agents / Q000737:chemistry; D008751:Methylene Blue / Q000737:chemistry*; D058086:Microalgae / Q000737:chemistry* / Q000302:isolation & purification*; D010084:Oxidation-Reduction; D062065:Wastewater / Q000382:microbiology*
chemical_list: D001391:Azo Compounds; D004396:Coloring Agents; D008751:Methylene Blue; D062065:Wastewater; C100258:methyl orange
keywords: Dye wastewater; Fenton-like reaction; Harvesting; Microalgae