ADSORPTION VOLTAMMETRIC DETERMINATION OF TRACE ORTHOPHOSPHATE IN SAMPLES OF TAP WATER AND NUTRITION

摘要

The voltammetric behavior of orthophosphate complex in a 0.4 mol/liter HCl-1.0 x 10(-4) mol/liter V(V)-3.0 x 10(-3) mol/liter ammonium molybdate medium is described. The complex can be adsorbed on a hanging mercury drop electrode and given a reduction peak whose peak potential is at -0.50 V (vs. standard calomel electrode). The derivative peak current is linearly proportional to the concentration for orthophosphate in the range from 1.0 x 10(-2) to 2.0 x 10(-6) mol/liter. The detection limit is 5.0 x 10(-9) mol/liter. The presence of acetone made the complex wave more stable. This sensitive and accurate method can be used to determine trace PO43- in tap water and nutritional samples. (C) 1996 Academic Press, Inc. [References: 5]