Skip to main content

Reaction of bentonites with pyrite concentrate after wetting and drying cycles at 80°C: relevance to radioactive waste (Radwaste) storage

Buy Article:

$13.61 plus tax (Refund Policy)

Abstract:

The mineral stability of two bentonites was studied in the presence of pyrite concentrate to simulate the possible reactions between the bentonite barrier used in a high-level nuclear waste (HLW) repository and host rock containing up to 5 wt.% of admixed pyrite. Smectite was the only bentonite mineral affected by pyrite treatment under the experimental conditions used. Bentonites reacted differently with pyrite due to the different nature of the smectites. The distinct crystal chemistry of the smectites controlled by the composition of the parent rocks influenced the smectite surface properties (cation exchange capacity and layer charge distribution) which resulted in a different response of the bentonites to pyrite treatment. A partial transformation of the original smectites into H-smectites represented the initial stage of smectite destabilization on acid attack. Rising non-equivalent isomorphous substitution in the octahedral sheets of the smectites enhanced smectite reactivity and thus the reaction between bentonite and pyrite, causing lower stability of the bentonite containing high-charge smectite.

Keywords: BENTONITE; HIGH-LEVEL NUCLEAR RADIOACTIVE WASTE STORAGE; HLW; LAYER CHARGE; NUCLEAR WASTE REPOSITORY; PYRITE OXIDATION; RADWASTE; SMECTITE; STABILITY; WETTING AND DRYING

Document Type: Research Article

DOI: http://dx.doi.org/10.1180/claymin.2012.047.4.06

Publication date: December 1, 2012

More about this publication?
minsoc/cm/2012/00000047/00000004/art00006
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
UA-1313315-23
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more