REFEX Technology overview
Major pH measurement problems such as drift, sluggish response and measurement error are often associated with the porous reference junction or conductive salt bridge of conventional electrodes. Being porous, the reference junction is very sensitive to fouling, poisoning, temperature/pressure changes, and diffusion/dilution of the electrolyte within the reference half-cell and all these factors can have a significant impact on the measurement performance. Short operating life of conventional electrodes in aggressive applications is often experienced and besides the cost of replacement electrodes, many man hours are expended in maintenance activities. The cost of using conventional electrodes, even so called “long-life” and “rugged application” designs, is high and an area o great opportunity for cost reduction.
REFEX electrodes still rely upon an Ag/AgCl element in a 3 mol/l KCl electrolyte (just like conventional technology probes, so they work with many standard pH transmitters) but in addition use a patented conductive polymeric material as a barrier between the process and the reference electrode. Unlike conventional electrodes that use open channels, diaphragms or other means to connect the reference electrode to the process, this solid barrier is non-porous, so the problems caused by to fouling, poisoning, temperature/pressure changes, and diffusion/dilution of the electrolyte are essentially mitigated.
Simply put, REFEX reference electrodes improve on conventional designs by eliminating the need to have a porous liquid junction in a pH (or ORP) measurement circuit.
The non-porous nature of REFEX: