A conductance sensor for dissolved sulphur dioxide using a series piezoelectric crystal device

Area of Science:

• Analytical Chemistry
• Materials Science

Background:

• Sulphur dioxide (SO2) is a common pollutant and its accurate determination is crucial.
• Existing methods for SO2 detection can be complex or lack sensitivity.

Purpose of the Study:

• To develop a new piezoelectric crystal impedance sensor for SO2 determination.
• To evaluate the sensor's performance characteristics and applicability to real-world samples.

Main Methods:

• A series piezoelectric crystal device was constructed with an AT-cut crystal and a probe.
• The probe incorporated an internal electrolyte separated by a gas-permeable membrane.
• Frequency response, detection limit, dynamic range, reproducibility, response time, and selectivity were investigated.

Main Results:

• The sensor demonstrated a favorable frequency response to sulphur dioxide concentrations from 1 x 10(-7) to 1 x 10(-3) M.
• A low detection limit of 1 x 10(-8) M was achieved.
• The sensor was successfully applied to determine sulphur in petroleum samples.

Conclusions:

• The developed piezoelectric crystal impedance sensor offers a sensitive and reliable method for SO2 determination in aqueous solutions.
• The sensor's successful application in petroleum analysis highlights its practical utility.