PRINCIPLE

 

The automated procedure for the determination of Sulfate is based on the turbidimetric measurement of barium sulfate. Barium chloride reagent reacts with sulfate in the sample to form an insoluble barium sulfate suspension. The barium chloride reagent is acidified to prevent precipitation of carbonate and phosphate.  Carboxymethyl cellulose is used to hold the barium sulfate in suspension. The chemisty is non-linear. Wash with EDTA prevents the accumulation of barium sulfate in the reactor.

The color intensity is measured at 520 nm