Towards the efficient reduction of perchlorate in water using rhenium-noble metal bimetallic catalysts supported on activated carbon.

Catalytic reduction in water is a potential alternative to replace current available techniques, such as adsorption or ion-exchange, for the efficient treatment of perchlorate contaminated waters. However, the development of an efficient catalytic system has been hindered by the perchlorate's very stable tetrahedral structure. This work aims to obtain an efficient catalytic system to degrade perchlorate in contaminated water at natural pH and mild operation conditions by optimizing the design of a supported catalyst. To this end, different metal combinations, using Pt, Pd, and Ru in combination with Re were tested. The most active metallic pairing (Re/Pt) was then used in a systematic study to optimize its composition. An optimal composition that promotes the formation of coordinated Re/Pt species was established. This facilitates the interaction of perchlorate with spilled-over hydrogen, consequently resulting in improved reaction rates above those reported elsewhere. The stability of the catalytic system was demonstrated in reutilization experiments under anoxic atmosphere. A systematic catalyst development study allows the rational design of a catalytic system to effectively remove perchlorate, a very stable water contaminant, from water. [Display omitted] • Bimetallic Re catalysts were prepared for the reduction of perchlorate in water. • A systematic study identified the most promising noble metal pairing for Re (Re/Pt). • Different metal weight contents were screened and an optimised ratio was found. • Catalytic activity trend was related to hydrogen uptake during pulse chemisorption. • Improved perchlorate removal was related with formation of Re/Pt surface species. [ABSTRACT FROM AUTHOR]