SU769424A1 - Device for measuring electrode potentials under non-standard conditions of electrolysis - Google Patents

Description

The wired input of which is connected to the output of a peak voltmeter, and the output to the third input of the recorder, and an additional peak voltmeter, the input of which is connected to the output of the first block of the subtraction, the control input to the output of the current pulse generator, and the output to the inverting input of the second block subtraction.

This gap is also achieved by the fact that the current pulse generator is designed as a modulated signal generator.

The drawing shows the functional electrical circuit of the device.

It consists of a current pulse generator 1, an electrochemical cell 2, a reference electrode. 5, a recorder 4, a peak voltmeter 5, a first subtraction unit 6, an additional volcmeter 7 and a second subtraction unit 8.

The current pulse generator / is connected to the working electrodes of the electrochemical cell 2 and the recorder 4, which in turn is connected to the outputs of the peak voltmeter 5 and the second subtraction unit 8. Comparison electrode 3 is connected to the input of the peak voltmeter 5 and the inverting input of the first subtraction unit 6, non-inverting The INPUT of which is connected to the output of the PI. Voltmeter 5, and the output to the input of the additional peak voltmeter 7. The control input of the voltmeter 7 is connected to the output of the generator /, and the output to the inverting input of the second unit ychita and 8, the non-inverting input of which is connected to the output of the voltmeter 5 faces.

The current pulse generator is a modulated signal generator, in which, depending on the mode selected, the operation changes over time in one of the polarizing pulse current parameters (amplitude, frequency, duty cycle) according to a certain law (linear, logarithmic, etc.). of the developable polarizing current parameter serves as a sweep signal of a two-channel two co-ordinator of a high-power repeater - caiMon Hicffl / a.

The electrochemical cell is designed to conduct electrochemical reandy on the working electrodes. The reference electrode serves to remove the potential of the electrode.

The recorder records the change in one parameter (frequency) depending on the change in another (for example, the amplitude of such a pulse, frequency or duty cycle). A peak voltmeter remembers the maximum value of a signal arriving at its input. The subtractor determines the difference between the input sigals.

The principle of the device is as follows. iC generator output. current pulses 1 polarizing current flows to the working electrodes of the electrochemical cell 2. As a result of the electrochemical reactions occurring in the cell, the potential of the electrode shifts relative to the equilibrium value. The potential difference between the working electrode and the reference electrode is fed to the input of the peak voltmeter 5 and the inverting input of the first subtraction unit 6. The peak voltmeter 5 (registers) remembers the maximum value of the input signal. From the output of the voltmeter 5, the voltage is applied to the recorder 4 and the inputs of the subtraction blocks 6 and 8. The output voltage of the first subtraction block 6 is equal to the difference between the maximum and current values of the electrode potential. The difference signal from the output of the first subtraction unit 6 is fed to the input of the voltmeter 7. Thus, the output voltage of the additional peak voltmeter 7 is equal to the maximum difference of the maximum and minimum values of the electrode potential. The signal from the output of the voltmeter 7 is fed to the inverting input of the second subtraction unit 8. The output voltage of the subtraction unit 8, equal to the minimum value of the electrode potential, also goes to the recorder 4. At the same time, the envelope from the current pulse generator enters the 4. The introduction of two blocks of subtraction, additional voltmeter voltmeter and the execution of a current pulse generator in the form of a generator modular-signal signal allows you to simultaneously record the dependence of the minimum and maximum

values of the electrode potentials from the parameters of the polarizing current. The use of the device allows the use of high-precision meters (peak voltmeter) to record both the maximum and

minimum values.

A sweep of one of the polarizing current parameters allows automatic detection of the electrode potential from this parameter.

Thus, the proposed device performs automatic measurement of the minimum and maximum values of the electrode potential; coKpaniaeT measuring time by -16 times due to reduction

preparatory and final time. Since in the prototype of the potential – current dependence (or another parameter), points are built, and time is spent on measuring at each point. In the proposed device, the sweep is continuous; It is possible to automatically record the dependences of the electrode potential both on the density of the pulsed current, and on its frequency and meaning. Increases

accuracy of measurement of the maximum and minimum values of the electrode potential. The measurement accuracy of + 1% is achieved in the device. However, this value is not the limit. High accuracy

Claims (3)

Measurements in the proposed device are achieved by using peak voltmeters for measuring, the accuracy of which is 1-2 times higher than the accuracy of the oscilloscope. Claims An apparatus for measuring electrode potentials under non-stationary electrolysis conditions, comprising a current pulse generator, an electrochemical cell, the working electrodes of which are connected to. a current pulse generator output, a reference electrode and a peak voltmeter connected in series, a recorder, one input of which is connected to the current pulse generator output and the other to a peak voltmeter output, characterized in that, for the simultaneous automatic measurement of the maximum and minimum electrode values potential and increase the accuracy of measurements, the first subtraction unit is inserted into the device, the 1 inverting input of which is connected to the reference electrode, the non-inverting input to the output of the peak voltmeter, the second subtraction unit, the non-inverting input of which is connected to the output of the peak voltmeter, and the output to the third input of the recorder, and an additional peak voltmeter, the input of which is connected to the output of the first subtraction unit, the control input to the output of the current pulse generator, and the output with the inverting input of the second | subtraction unit, the current pulse generator I1 being designed as a modulated signal generator. Sources of information, taken into account in the examination: 1. Podobaev N. I., Electrochemistry, M., “Enlightenment, 1977, p. 91-100. 2. Gutnikov V.S.. Application of operational amplifiers in measuring equipment. L., “Energie, 1975, p. 70-72. 3. Measurement methods in electrochemistry. Volume 1, M., “Peace, 1977, p. 227.