Dual-Membrane pH Electrode
Mettler Toledo Process Analytics has announced the launch of a pH electrode designed specifically for the requirements of the chlor-alkali industry. The InPro 4850i incorporates a sodium-sensitive glass membrane, which uses the brine present in chlorine production as a reference, and additionally features:
- Hermetically sealed design, providing a barrier against oxidizing agents that poison other sensors — this feature, combined with digital transmission of the measurement signal, makes the electrode ideally suited to chlorine production.
- Unlike almost all other pH electrodes, this electrode does not have a diaphragm, so poisoning of the electrode's sodium reference system is impossible (this design ensures stable measurement and eliminates sensor drift).
- The electrode’s high-quality pH-sensitive glass membrane is extremely resistant to chlor-alkali process conditions, ensuring precise pH measurement.
- The sodium-sensitive glass has a very high impedance, which, when combined with the impedance of the cable between sensor and transmitter, means that the signal from the sensor is highly sensitive to interference from surrounding equipment —even touching or simply approaching the measurement system can create a change in the output.