Powell Fabrication & Manufacturing, Inc.

ORP Electrode




Powell has been involved in the sodium hypochlorite (NaOCl) and chlorine (Cl2) industry since 1964 and is a leading innovator and provider of equipment to safely and efficiently produce, filter, dilute, store, monitor, load, and unload chlorine, sodium hypochlorite, sodium hydroxide, sulfur dioxide, methanol, ammonia, phosgene, hydrochloric acid, phosphoric acid, and a variety of other chemicals.


Powell offers customized solutions for the safe handling and containment of hazardous gases.

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Control the Reaction of Chlorine and Caustic Soda When Manufacturing Sodium Hypochlorite with ORP Electrodes

The reaction of chlorine and caustic soda that results in the manufacture of sodium hypochlorite must be controlled to ensure that the end product - bleach  - is of the desired excess caustic level. The batch end point is critical because a finished bleach that contains high excess caustic may result in slower bleaching speed and inefficient use of raw materials. Conversely, an over-chlorinated product may be seriously unstable and may result in a hazardous release.

ORP The preferred way to monitor the reaction is by Oxidation Reduction Potential - commonly referred to as ORP. The use of ORP is a simple and accurate way to maximize the use of raw materials to produce a product with maximum stability and improved bleaching speed.

The standard Powell Hypo Batch Controller uses the principle of ORP to monitor the caustic remaining in the batch system. ORP electrodes, when placed in a bleach solution, produce a voltage inversely proportional to the amount of excess caustic in the solution. Given the same amount of excess caustic, the electrodes will consistently produce the same voltage. This allows the bleach producer to establish a given set point on the controller that yields bleach with a consistent excess caustic end point.

Oxidation-Reduction Potential Electrodes - Years of Proven Service

  • Kynar® electrode holder designed to fit between companion flanges.
  • Kynar® electrode body.
  • PVC moisture-resistant dust caps.
  • No electrolyte solution.
  • Direct in-line usage.
  • Optional electrode holders for other applications