Automatic colorimetric titration - using light emitting diodes of different wavelengths with receptor cell to detect colour change w.r.t. reagent addition

摘要

Automatic colorimetric titrator uses >=1 light source to irradiate the liquid being titrated. Behing the vessel contg. the sample is a light sensitive cell which emits a signal to control the input of reagent proportional to the light being transmitted by the liquid. Light emitting diodes are used emitting light in the wavelength bands 150 - 3500 (500 - 1500) nm. These are actuated by impulses in a frequency range between 0.1-100 (1-5)K esp. 1 to 5 kHz, and alternately transmit a beam through the sample. The frequencies selected correspond to the colours of the sample before and after the colour change. The detector cell generates an a.c. potential signal on the colour change. Laser diodes can be used. Used for carrying out the automatic titration of solns. and permits the use of any convenient vessel with the need for additional manipulation.