Extremely Rapid Uptake of Perchlorate with Release of an Environmentally Benign Anion: Silver Bipyridine Acetate

Abstract

We report the selective removal of perchlorate from water by a cationic coordination polymer in the highest observed capacity and rate to date. Silver bipyridine acetate [Ag(4,4′-bipy)+][CH3CO2–]·6H2O (bipy = bipyridine) is easily synthesized in water under ambient conditions (60 min with 99.1% yield). The material releases its environmentally benign acetate anions upon perchlorate uptake to 99.9% mol/mol completion in Millipore water. Actual contaminated industrial water from an underground plume (53 ppm initial perchlorate concentration) was treated to 96% mol/mol in 60 min. The uptake capacity is near-record high at 310 mg/g and is 94% complete within 30 min. Perchlorate exchange was also conducted at 1–30 ppm perchlorate typical of underground contaminated source sites, with up to 99.7% mol/mol completion.