Sorption of uranium(6+) and neptunium(5+) by surfactant-modified natural zeolites
Abstract
Experiments were conducted to determine the ability of surfactant-modification to enhance the ability of natural zeolites to sorb U(6+) and Np(5+). Natural zeolite material, comprised mainly of clinoptilolite and treated with the cationic surfactant hexadecyltrimethylammonium-bromide (HDTMA), was reacted with U(6+) and Np(5+) solutions open to the atmosphere and having a range of radionuclide concentration, pH, and NaCl concentration. The results indicate surfactant-modification of the zeolite enhances its ability to sorb U(6+), particularly at pHs greater than six where U(6+) sorption on unmodified zeolite is typically low due to formation of anionic U(6+) aqueous carbonate complexes. In contrast, there is little enhancement of Np(5+) sorption onto surfactant-modified zeolite. The presence of chloride anions in solution makes surfactant-modification less effective. The enhanced sorption of U(6+) is interpreted to be due to anion exchange with counterions on the external portion of a surfactant bilayer or admicelles.
- Authors:
- Publication Date:
- Research Org.:
- Southwest Research Inst., San Antonio, TX (US)
- OSTI Identifier:
- 20015861
- Resource Type:
- Conference
- Resource Relation:
- Conference: 1998 Materials Research Society Fall Meeting, Boston, MA (US), 11/30/1998--12/04/1998; Other Information: Single article reprints are available from University Microfilms Inc., 300 North Zeeb Road, Ann Arbor, Michigan 48106; PBD: 1999; Related Information: In: Scientific basis for nuclear waste management XXII. Materials Research Society symposium proceedings: Volume 556, by Wronkiewicz, D.J.; Lee, J.H. [eds.], 1355 pages.
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; 54 ENVIRONMENTAL SCIENCES; URANIUM COMPOUNDS; NEPTUNIUM COMPOUNDS; SORPTION; ZEOLITES; SORPTIVE PROPERTIES; SURFACTANTS; SURFACE TREATMENTS; REMEDIAL ACTION; GROUND WATER; IN-SITU PROCESSING
Citation Formats
Prikryl, J D, and Pabalan, R T. Sorption of uranium(6+) and neptunium(5+) by surfactant-modified natural zeolites. United States: N. p., 1999.
Web.
Prikryl, J D, & Pabalan, R T. Sorption of uranium(6+) and neptunium(5+) by surfactant-modified natural zeolites. United States.
Prikryl, J D, and Pabalan, R T. 1999.
"Sorption of uranium(6+) and neptunium(5+) by surfactant-modified natural zeolites". United States.
@article{osti_20015861,
title = {Sorption of uranium(6+) and neptunium(5+) by surfactant-modified natural zeolites},
author = {Prikryl, J D and Pabalan, R T},
abstractNote = {Experiments were conducted to determine the ability of surfactant-modification to enhance the ability of natural zeolites to sorb U(6+) and Np(5+). Natural zeolite material, comprised mainly of clinoptilolite and treated with the cationic surfactant hexadecyltrimethylammonium-bromide (HDTMA), was reacted with U(6+) and Np(5+) solutions open to the atmosphere and having a range of radionuclide concentration, pH, and NaCl concentration. The results indicate surfactant-modification of the zeolite enhances its ability to sorb U(6+), particularly at pHs greater than six where U(6+) sorption on unmodified zeolite is typically low due to formation of anionic U(6+) aqueous carbonate complexes. In contrast, there is little enhancement of Np(5+) sorption onto surfactant-modified zeolite. The presence of chloride anions in solution makes surfactant-modification less effective. The enhanced sorption of U(6+) is interpreted to be due to anion exchange with counterions on the external portion of a surfactant bilayer or admicelles.},
doi = {},
url = {https://www.osti.gov/biblio/20015861},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jul 01 00:00:00 EDT 1999},
month = {Thu Jul 01 00:00:00 EDT 1999}
}