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Published on: February 20, 2020
Bromine number determination by coulometric flow-injection titration.
R H Taylor1, C Winbo, G D Christian
1Center for Process Analytical Chemistry, Department of Chemistry, BG-10, University of Washington, Seattle, WA 98195, U.S.A.
Talanta
|July 1, 1992
Summary
A new coulometric flow-injection titration (CFIT) method accurately determines bromine numbers in petroleum products. This technique offers advantages over traditional methods, including automation and reduced waste.
Area of Science:
- Analytical Chemistry
- Industrial Chemistry
Background:
- Bromine number is a critical parameter in the chemical and petroleum industries.
- Conventional methods for bromine number determination can be cumbersome and require significant reagent volumes.
Purpose of the Study:
- To describe a novel method for bromine number determination using coulometric flow-injection titration (CFIT).
- To evaluate the accuracy and reliability of the CFIT method compared to conventional titrations.
Main Methods:
- Utilized sequential injection with sinusoidal flow and single zone techniques for coulometric flow-injection titration.
- Performed titrations on olefins, interfering compounds, and petroleum distillates.
- Compared CFIT results with those from conventional bromine number titrations.
Main Results:
- Achieved a relative standard deviation of 2% in analyses.
- CFIT results favorably compared with conventional methods for olefins and petroleum distillates.
- The method demonstrated insensitivity to interference from nitrogen compounds.
Conclusions:
- Coulometric flow-injection titration (CFIT) provides an accurate and reliable method for bromine number determination.
- CFIT combines the benefits of coulometric titrations (controlled reagent generation) with flow-injection analysis (small volumes, automation).
- This technique offers advantages in terms of cost, waste reduction, and safety for industrial applications.
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