Low-cost Free Chlorine Sensor

About

Background Water disinfection is directly responsible for a rapid drop in human illness caused by microorganisms. Chlorine is widely used as a disinfectant in water treatment, where the dosage is dependent on the characteristics of the influent water and the desired residual levels within the municipal piping to ensure safe, clean drinking water arrives at the tap. Unfortunately, high concentrations of free chlorine can be toxic to humans, cause irritation, or have an unpleasant taste. As a result, there is a desire in many sectors to ensure that the free chlorine levels are within acceptable ranges. Current methods for the detection of free chlorine use exotic and expensive materials or have the undesirable characteristic of leaching hazardous materials into the water supply. The golden standard for measuring free chlorine is based on colorimetry, however, that method does not allow for real time sensing. Technology Overview This technology employs a method of detecting free chlorine using a graphite-based electrode that can be modified from inexpensive and readily available sources. As it is a chronoamperometric measurement system, fully electronic, and allows for dynamic real-time sensing. It has a low hysteresis and fast response time providing a significant improvement over the existing methods. Stage of Development: • Prototype constructed and tested • Data is available upon request • Optimization continuing • Manufacturable prototype being developed