Experimental Determination of contaminant Metal Mobility as a Function of Temperature, Time, and Solution Chemistry

Carroll, Susan A. ; O' ; Day, Peggy A.

Lawrence Livermore National Laboratory

关键词: Attenuation;    37 Inorganic, Organic, Physical And Analytical Chemistry;    Clays;    Wastes;    Sorption;   

DOI  :  10.2172/828097
RP-ID  :  EMSP-55249--2000
RP-ID  :  828097

美国|英语

来源: UNT Digital Library

【 摘 要 】

During the FY96-FY99 funding cycle we examined the uptake of aqueous strontium onto goethite, kaolinite, and amorphous silica surfaces as a function of pH, total strontium, and temperature. Our overall goal was to produce a mechanistic sorption model that can be used in reaction-transport calculations to predict the mobility and attenuation of radioactive strontium (90Sr) in the environment. Our approach was to combine structural information derived from EXAFS analysis together with macroscopic uptake data and surface complexation models to clarify the physical and chemical structure of sorbed complexes. We chose to study these solids because of the prevalence of clays and iron hydroxides in natural systems, and because silica colloids probably form beneath leaking tanks at Hanford as caustic waste is neutralized. We have published the spectroscopic work in two papers in the Journal of Colloid and Interface Science [1, 2], and will soon submit at third manuscript to Geochemical Transactions [3] combining the sorption and spectroscopic data with a mechanistic complexation model.