Additive for reducing chromium (VI) to chromium (III) ions
AssigneeChryso
InventorsPierre-Antoine Andreani, Bruno Pellerin, Karen Ayme
Life of this patent
Estimating the term…
Abstract
The invention relates to an additive for reducing Cr(VI) ions to Cr(III) ions, comprising a complex of tin(II) and a carboxylic acid or a salt thereof, and to the process for the preparation thereof. It also relates to a process for preparing a material having a low chromium(VI) content. Finally, it relates to the use of said additive for reducing chromium(VI) ions to chromium(III) ions.
Claims11
A process for decreasing the chromium (VI) content of a hydraulic binder, the process including the step of contacting the hydraulic binder with an effective amount of an additive comprising an aqueous solution of a tin(II) complex formed between tin(II) ions and a carboxylic acid or a salt thereof to reduce Cr(VI) ions to Cr(III) ions.
Dependencies are inferred from the claim text.