The Research of Phosphoric Acid Content Detection by Ammonium Molybdate Spectrophotometry

Based on ammonium molybdate spectrophotometric method, a detection method was established to determine industrial phosphoric acid content. Recovery of sample was between 100%~109%; the relative standard deviation of test results precision was less than 4.0%; the concentration of sample phosphorus had a preferable linear correlation in the range of 0.02~0.72 mg/L, method for synthesis uncertainty was about 1.8041%; specificity experiments showed that phosphoric acid with impurity did not affect the accuracy of measurement. The average to determine two industrial phosphoric acid with 85% concentration were 84.738% and 83.152%, and the average recovery were 100.20% and 104.09%. Ammonium molybdate spectrophotometric method can apply to the determination of phosphate content in sugar mill industry.