Open AccessExperimental determination of contaminant metal mobility as a function of temperature time and solution. 1998 annual progress report
Author(s) -
S Carroll,
C.J. Bruton,
P O'Day,
Nita Sahai
Publication year - 1998
Language(s) - English
Resource type - Reports
DOI - 10.2172/13543
Subject(s) - goethite , gibbsite , sorption , dissolution , kaolinite , aluminosilicate , desorption , chemistry , analytical chemistry (journal) , absorption (acoustics) , inorganic chemistry , mineralogy , materials science , environmental chemistry , adsorption , biochemistry , composite material , catalysis
'The objective of this work is to determine the fundamental data needed to predict the behavior of {sup 90}Sr at temperature and time scales appropriate to thermal remediation. The authors approach combines macroscopic sorption/precipitation and desorption/dissolution kinetic experiments which track changes in solution composition with direct molecular characterization of Sr in the solid phase using x-ray absorption spectroscopy. These experiments will be used to identify mechanistic geochemical reactions and their thermochemical properties that will be incorporated into geochemical computer codes. As of May 1998, the authors have completed most of the static sorption experiments as a function of temperature (25, 60, and 80 C), solution pH (4 to 10), initial Sr concentrations (10{sup -7} to 10{sup -3} M), and partial pressure of CO 2 (100% N 2 or atmospheric CO 2 ). They chose to study goethite, kaolinite, gibbsite, and amorphous silica because iron and aluminum (oxy)hydroxides, aluminosilicate clays, and quartz are key components in soils, sediments, and aquifers. The authors have completed x-ray absorption analysis of Sr sorption to kaolinite and goethite at 25{sup -}C, initial Sr of 10{sup -}3 M, and pH 9.