Detecting odorous materials in water using quartz crystal microbalance sensors

Area of Science:

• Environmental Science
• Analytical Chemistry
• Sensor Technology

Background:

• River water purification requires continuous monitoring for odorous contaminants, such as oil and organic solvents.
• Untimely or failed detection of these pollutants can lead to severe consequences for water safety.

Purpose of the Study:

• To develop a highly sensitive water-monitoring system for detecting odorous materials.
• To address the sensitivity of electronic noses to humidity and temperature.

Main Methods:

• Utilized a highly sensitive electronic nose composed of quartz crystal microbalance sensors.
• Developed a method for precise humidity and temperature control within the sensor cell.
• Tested the system's ability to detect petroleum hydrocarbons, gasoline, kerosene, and benzene.

Main Results:

• The electronic nose detected petroleum hydrocarbons at a low-ppb level, even without water vapor.
• The developed system effectively maintained stable humidity and temperature conditions.
• Quick detection of water contaminated with gasoline, kerosene, or benzene at several hundred ppb levels was achieved.

Conclusions:

• The developed water-monitoring system offers a sensitive and rapid method for detecting odorous contaminants.
• The system's ability to classify pollutants using pattern recognition of sensor response shows promise.
• Continuous, real-time water quality monitoring is feasible with this technology.