Orano Demantelement

Institut Francais Des Sciences Et Technologies Des Transports, De L'amenagement Et Des Reseaux

UniversitÉ Gustave Eiffel

Lavinia Stefan

Thierry Chaussadent

Hela Bessaies-Bey

Nadia Dominique

Mathieu Le Rouzic

Hela Bessaies-bey

A use of a thiosulfate as a retarder for a cement paste comprising a magnesium phosphate cement.

Thiosulfates for use as retarders for magnesium phosphate cement pastes

A process for immobilizing a mercury-containing waste, which comprises: &#x2014;stabilizing the mercury of the waste by precipitating the mercury as mercury (II) sulfide; then &#x2014;encapsulating the waste by cementation, the cementation comprising coating the waste in a cement paste obtained by mixing a composition comprising a powder of at least one binder chosen from hydraulic cements, alkali-activated cements and acid-activated cements, with an aqueous mixing solution, then hardening the cement paste; and which is characterized in that the precipitation of the mercury as mercury (II) sulfide is obtained by reacting the mercury with a thiosulfate in a basic aqueous medium, while stirring and in the presence of a sulfide of an alkali metal, the molar ratio of the thiosulfate to the mercury being at least equal to 1.

Method for immobilizing a mercury-containing waste

Growing community of inventors

Saint Germain-en-Laye, France

Lavinia Stefan