DETERMINATION OF SULFATE AND PHOSPHATE BY FLOW-INJECTION ANALYSIS USING A BARIUM CHLORANILATE PACKED-COLUMN

A flow-injection analysis Of sulphate using a reaction column packed w ith barium chloranilate (BaCh) is described. The chloranilate ion rele ased by the reaction is monitored at the isosbestic point (310 nm) of chloranilate. An aqueous solution of 2-propanol (60%) is used as the c arrier solution at a flow-rate of 1 ml . min-1. The linear dynamic ran ge of the detection system is approximately 2.5 x 10(-6) approximately 1.0 X 10(-3) mol/l per 10 mul sample injection. The time required for a determination is only 20 s per sample injection. The method has als o been applied to the amplified determination of phosphate by reaction with molybdate resulting from the decomposition of molybdophosphate ( H3PO4 . MoO3) extracted.