title: Preparation of modified-biochar from Laminaria japonica: Simultaneous optimization of aluminum electrode-based electro-modification and pyrolysis processes and its application for phosphate removal.
abstract: The preparation conditions of electro-modification (current density) and pyrolysis (pyrolysis temperature and heating rate) processes were simultaneously optimized using response surface methodology with the quadratic regression model associated with Box-Behnken design. By numerical optimization, the phosphate adsorption capacity of 245.06mg/g was achieved, corresponding to 99.9% of the predicted values under statistically optimized conditions (current density: 38.78mA/cm(2), pyrolysis temperature: 584.1°C, heating rate: 6.91°C/min). By considering R(2) and three error functions values, the experimental results of adsorption kinetics, and the equilibrium isotherms at different temperatures (10-30°C) showed that predictive pseudo-second-order and Sips isotherm models could adequately interpret the phosphate adsorption process for 'statistically optimized electrically modified'-biochar (SOEM-biochar). The maximum phosphate adsorption capacities of SOEM-biochar were found to be 273.9, 345.1, and 460.3mg/g at 10, 20, and 30°C, respectively, which are higher than that of other adsorbents reported in the literature.
authors.affiliation: Center for Water Resources Cycle Research, Korea Institute of Science and Technology, 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, South Korea.
authors.forename: Kyung-Won
authors.initials: KW
authors.lastname: Jung
authors.affiliation: Center for Water Resources Cycle Research, Korea Institute of Science and Technology, 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, South Korea.
authors.forename: Tae-Un
authors.initials: TU
authors.lastname: Jeong
authors.affiliation: Civil and Environmental Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 03722, South Korea.
authors.forename: Ho-Jeong
authors.initials: HJ
authors.lastname: Kang
authors.affiliation: Department of Environmental Engineering, Korea maritime and Ocean University, 727 Taejong-ro, Yeongdo-gu, Busan 49112, South Korea.
authors.forename: Jae-Soo
authors.initials: JS
authors.lastname: Chang
authors.affiliation: Center for Water Resources Cycle Research, Korea Institute of Science and Technology, 5 Hwarang-ro 14-gil, Seongbuk-gu, Seoul 02792, South Korea. Electronic address: khahn@kist.re.kr.
authors.forename: Kyu-Hong
authors.initials: KH
authors.lastname: Ahn
mesh_terms: D000327:Adsorption; D000535:Aluminum / Q000737:chemistry*; D001709:Biotechnology / Q000379:methods*; D002606:Charcoal / Q000737:chemistry*; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007795:Laminaria / Q000737:chemistry*; D010710:Phosphates / Q000302:isolation & purification*; D012996:Solutions; D013696:Temperature; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*
chemical_list: D010710:Phosphates; D012996:Solutions; D014874:Water Pollutants, Chemical; C540010:biochar; D002606:Charcoal; D000535:Aluminum
keywords: Biochar; Electro-modification; Equilibrium isotherms; Kinetics; Phosphate; Response surface methodology