A ph electrode with fast response to temperature

Abstract

The invention discloses a pH electrode capable of quickly responding to temperature. The solution of liquid redox couple containing triiodide ions is taken as the reference system solution in the pH electrode. The mole ratio of triiodide ions to iodine in the reference system solution is 0.005-0.02; the reference system solution in the pH electrode further comprises potassium hydroxide or boric acid solution and the concentration is zero-temperature coefficient; the pH value of the reference system solution is 7.10. A pH electrode shell of the pH electrode is communicated with a sensitive ball bulb; a measuring electrode stretches into the internal reference solution in the sensitive ball bulb from the electrode shell; the measuring electrode is arranged in the middle of the sensitive ball bulb; a temperature compensating electrode is inserted into the sensitive ball bulb or is arranged on the exterior of the sensitive ball bulb and on the interior of the electrode shell; a reference electrode is inserted into the external reference solution. The pH electrode provided by the invention is sensitive to the change response of temperature; the stabilizing time is prolonged; the liquid interface is difficult to block; the service life is prolonged.

Description

technical field [0001] The invention relates to the technical field of material analysis, in particular to a pH electrode that responds quickly to temperature. Background technique [0002] A pH electrode, also known as a pH probe or a pH sensor, is a device used to measure the electrode potential on the part of the pH meter that is in contact with the substance to be measured. When measuring pH, the ability to respond quickly to temperature is critical to the accuracy of the measurement. At present, the domestic electrodes are silver / silver chloride to lead the potential of the measuring electrode and the potential of the reference electrode, which have the disadvantages of slow influence and easy blockage of the liquid junction, especially in the case of temperature changes, due to the influence of silver / silver chloride Due to the influence of its own slow dissolution characteristics, it takes half an hour to measure a potential to be stable, which cannot meet the requir...

AI Technical Summary

Problems solved by technology

At present, the domestic electrodes are silver / silver chloride to lead the potential of the measuring electrode and the potential of the reference electrode, which have the disadvantages of slow influence and easy blockage of the liquid junction, especially in the case of temperature changes, due to the influence of silver / silver chloride Due to the influence of its own slow dissolution characteristics, it takes half an hour to measure a potential to be stable, which cannot meet the requirements of rapid temperature changes at all.

[0003] There are usually two structures of the existing temperature compensation electrode: one is that the temperature compensation electrode is placed outside. This structure is to place the temperature compensation electrode probe in an open container. Since the solution surface contacts the air, the heat is dissipated quickly, thus forming a The temperature gradient from top to bottom causes the measured temperature value to not be the actual temperature value of the measuring electrode, which affects the temperature compensation and cannot obtain the correct measured value

One is to place the temperature compensation electrode in the reference solution. Due to the heat dissipation effect of the heating hole, or the heat insulation effect of the reference solution and the inner tube, the temperature measured at high temperature is not the actual temperature of the solution. The increase will cause the actual temperature to differ by up to about 5°C, and the impact on the pH value will reach about 0.05PH, which greatly affects the accuracy of the measurement

Images