title: Application of ordered nanoporous silica for removal of uranium ions from aqueous solutions.
abstract: Ordered nanoporous silica (MSU-H) with high surface area has been utilized as a solid substrate of a surface-modified hybrid sorbent for the application to the removal of U(VI). Carboxymethylated polyethyleneimine (CMPEI) with a strong complexing property has been introduced to the pore surface of MSU-H substrate. CMPEI-modified MSU-H (CMPEI/MSU-H) has been characterized by scanning electron microscopy and nitrogen sorption. In a kinetic experiment for 12.5 ppm U(VI) solution at pH 4.0, 99% U(VI) was removed from solution by the hybrid sorbent within less than 10 min, indicating that the sorption of U(VI) on the CMPEI/MSU-H proceeds very rapidly. It was evident that a U(VI) sorption capacity increased with pH in the range of 2.0 to 4.0. The CMPEI/MSU-H showed a high sorption capacity of 153 mg/g-sorbent at pH 4.0. In particular, the CMPEI/MSU-H showed a significantly high uranium loading stability. Only about 1% U(VI) was released out of CMPEI/MSU-H during 4 months, when the CMPEI/MSU-H was treated with polyacrylic acid.
authors.affiliation: Department of Chemistry, BK21 School of Chemical Materials Science, Sungkyunkwan University, Suwon, 440-746, Korea.
authors.forename: Hyung Ik
authors.initials: HI
authors.lastname: Lee
authors.forename: Jin Hoe
authors.initials: JH
authors.lastname: Kim
authors.forename: Ji Man
authors.initials: JM
authors.lastname: Kim
authors.forename: Seok
authors.initials: S
authors.lastname: Kim
authors.forename: Jung-Nam
authors.initials: JN
authors.lastname: Park
authors.forename: Jae Sik
authors.initials: JS
authors.lastname: Hwang
authors.forename: Jei-Won
authors.initials: JW
authors.lastname: Yeon
authors.forename: Yongju
authors.initials: Y
authors.lastname: Jung
mesh_terms: D000327:Adsorption; D010316:Particle Size; D011094:Polyethyleneimine / Q000737:chemistry; D016062:Porosity; D011312:Pressure; D012044:Regression Analysis; D012822:Silicon Dioxide / Q000737:chemistry*; D014501:Uranium / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*
chemical_list: D014501:Uranium; D012822:Silicon Dioxide; D011094:Polyethyleneimine