Acid chrome blue K catalytic spectrophotometric determination of fluoride inwater

In sulphuric acid medium,Free Fluorion can catalyze discoloration reaction of acidic chrome blue K with KBrO3 Based on this point,a novel catalytic spectrophotometric method to determine trace F-was proposed.The results show that the maximum absorption wavelength of the color solution is 523 nm,the linear range of the determination is 0.2~6.0μg/mL,and the detection limit is 0.1031μg/mL.The method was used to determine fluoride in the water with the relative standard deviations(RSD)of 0.65%~0.76%and the recovery of 99.5%~105%.