Clay mineral weathering and contaminant dynamics in a caustic aqueous system

Details Clay mineral weathering and contaminant dynamics in a caustic aqueous system Clay mineral weathering and contaminant dynamics in a caustic aqueous system

Sep 2005

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2005gecoa..69.4437c&link_type=abstract

Geochimica et Cosmochimica Acta, Volume 69, Issue 18, p. 4437-4451.

Computer Science

1

Scientific paper

Microscopic and spectroscopic studies were conducted to assess mineral transformation processes in aqueous suspensions of illite (Il), vermiculite (Vm) and montmorillonite (Mt) that were subjected to weathering in a simulated high-level radioactive tank waste leachate (0.05 m AlT, 2 m Na+, 1 m NO3-, pH ˜14, Cs+ and Sr2+ present as co-contaminants). Time series (0 to 369 d) experiments were conducted at 298 K, with initial [Cs]0 and [Sr]0 concentrations from 10-5 to 10- mol kg-. Incongruent clay dissolution resulted in an accumulation of secondary aluminosilicate precipitates identified as nitrate-sodalite, nitrate-cancrinite and zeolite X, by molecular spectroscopy and electron microscopy (XRD, IR, NMR, SEM-EDS and TEM-EDS). Contaminant fate was dependent on competing uptake to parent clays and weathering products. TEM-EDS results indicated that high Il affinity for Cs was due to adsorption at frayed edge sites. The Il system also comprised Sr-rich aluminous precipitates after 369 d reaction time. In Mt systems, Cs and Sr were co-precipitated into increasingly recalcitrant spheroidal precipitates over the course of the experiment, whereas contaminant association with montmorillonite platelets was less prevalent. In contrast, Cs and Sr were found in association with weathered Vm particles despite the formation of spheroidal aluminosilicate precipitates that were comparable to those formed from Mt dissolution.

Affiliated with

Also associated with

No associations

Rating

Clay mineral weathering and contaminant dynamics in a caustic aqueous system does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Clay mineral weathering and contaminant dynamics in a caustic aqueous system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Clay mineral weathering and contaminant dynamics in a caustic aqueous system will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1286400