title: Removal of trace Cd2+ using continuous multistage ion foam fractionation: part I--The effect of feed SDS/Cd molar ratio.
abstract: In this research, a continuous multistage ion foam fractionation column with bubble-cap trays was employed to remove cadmium ions from simulated wastewater having cadmium ions at a low level (10 mg/L). In this study, sodium dodecyl sulfate (SDS) was used to generate the foam. An increase in feed SDS/Cd molar ratio enhanced the removal of Cd. However, the SDS concentration above a certain level resulted in wetter foams, leading to having a high volume of generated foam that lowered both the enrichment ratio and separation factor of the Cd. The SDS recovery tended to increase with increasing feed SDS/Cd molar ratio. The molar ratio of SDS/Cd in foamate was found to be close to the theoretical adsorption molar ratio of 2/1 on the air-water interface of foam when the system was operated at a feed SDS/Cd molar ratio in the range of 2/1-7/1. Ion foam fractionation has been demonstrated in this study to be a promising technique for high heavy metal removal (more than 99%) for a feed having a low heavy metal concentration in the ppm (mg/L) level.
authors.affiliation: The Petroleum and Petrochemical College, Chulalongkorn University, Soi Chula 12, Phyathai Road, Pathumwan, Bangkok 10330, Thailand.
authors.forename: Visarut
authors.initials: V
authors.lastname: Rujirawanich
authors.forename: Sumaeth
authors.initials: S
authors.lastname: Chavadej
authors.forename: John H
authors.initials: JH
authors.lastname: O'Haver
authors.forename: Ratana
authors.initials: R
authors.lastname: Rujiravanit
mesh_terms: D002104:Cadmium / Q000302:isolation & purification*; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry*
chemical_list: D002104:Cadmium; D012967:Sodium Dodecyl Sulfate