Microcontroller (MCS-51) based optoelectronic system for the determination of metal and non metal ions

Abstract

An optoelectronic system using Microcontroller 89C51 for measurement of concentration, absorption and transmission of inorganic phosphate phosphorous is described. Phosphorous reacts with potassium antimony tartrate and ammonium molybdate solution to form phosphoantimonyl molybdate complex, which on reduction with ascorbic acid forms blue colour. This blue coloured complex shows absorption maxima at 695 nm and obeys Lambert-Beer’s law in the concentration range of 0.05-1.00 ppm. Tungsten lamp is used as a light source with a grating (600 lines/mm) to obtain a linear spectrum. A sine drive is used along with the stepper motor that can adjust the grating to achieve the desired wavelength (695 nm). Silicon photodiode is used as a detector having peak spectral response at 800 nm.