1990 Volume 6 Issue 5 Pages 711-714
The concentration of sulfate ions in rain water was determined by a flow-injection method using a reaction column packed with barium chloranilate powder. Aqueous ammonium chloride (0.5%) containing 50% ethanol was used as a carrier at a flow rate of 1.9ml/ min. The chloranilate ion concentration, which corresponds to the sulfate ion concentration, in the carrier from the reaction column was monitored by a photometric detector at 530nm. Interferences by multivalent cations were eliminated with the use of a cation-exchange column inserted in the upper stream of the reaction column. The concentrations of sulfate ions in rain water (4-100ppm) were quickly determined (one sample per minute) with high reproducibility. The results agreed well with those obtained by the standard manual method.
