LimsPulse
Titration & electrochemistry

Potentiometric Titrator (Autotitrator)

Adds a titrant from a motorised burette while an electrode measures the potential of the solution, and finds the equivalence point from the change in potential. Used for assays, standardisation and many limit tests.

  • Pharmaceutical
  • Chemicals
  • Food & beverage
  • Environmental
  • Metal finishing
Photo of a Potentiometric Titrator (Autotitrator)
Photo: User:FA2010, Public domain (cropped), via Wikimedia Commons
Follow your site SOP
This is a typical operating sequence for learning. Your instrument model and approved SOP take precedence.
STAGE 1

Before you start

  1. 1Check the titrator and burette are within their calibration due dates.
  2. 2Check the titrant label for its standardised molarity and expiry date of the titre.
  3. 3Inspect the electrode: electrolyte level, diaphragm not blocked, glass membrane clean and not dry.
  4. 4Run the electrode check (for pH titrations) as per SOP.
  • Never let a glass electrode dry out; store it in the recommended storage solution.
STAGE 2

Preparing the burette

  1. 1Rinse the burette with fresh titrant (prepare or flush cycles) to remove air bubbles and old titrant.
  2. 2Check there are no bubbles in the cylinder or tubing.
STAGE 3

Titration

  1. 1Accurately weigh the sample into a clean beaker and dissolve it in the solvent specified in the method.
  2. 2Immerse the electrode and burette tip below the liquid surface, without touching the stirrer bar.
  3. 3Enter the sample mass and start the method.
  4. 4Run a blank titration if the method requires one.
  5. 5Review the titration curve: there should be a single clear inflection at the expected volume.
  • Check that the software found the correct equivalence point; a noisy or flat curve can give a false one.
STAGE 4

Shutdown

  1. 1Rinse the electrode with the appropriate solvent and water and place it in storage solution.
  2. 2Close the titrant bottle; protect NaOH from carbon dioxide with a soda-lime tube.
  3. 3Complete the usage log.
In LimsPulse · Calibration Management

Keep every Potentiometric titrator in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.

See how