Spectrophotometric determination of phosphate in natural waters by microwave catalytic chromogenic reaction

Study on microwave catalytic effect on chromogenic reaction of phosphomolybdic blue using ascorbic acid as a reducing reagent in spectrophotometric determination of phosphous was performed and proper conditions were evaluated as well. The experimental results showed that the chromogenic reaction was completed in 3 min and kept stable up to 48 h. Beers law was obeyed in the range of 01.0 mg/L. The molar absorptivity was _(700 nm)=1.710~4 Lmol~(-1)cm~(-1). The ralative standard deviation was no more than 2.5% and the recoveries were in the range of 98.6%103% by the determination of water samples(n=7). There was no significant difference between the proposed method and the national standard method.