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An easy spectrophotometric acid-base titration protocol for dissolved organic matter
Marawit Tesfa1, Aline Dia1, Malou Ollivier1
1University of Rennes, CNRS, Géosciences Rennes - UMR 6118, Rennes, France.
Methodsx
|May 20, 2022
Summary
A new buffer method for UV-vis spectrophotometric acid-base titration speeds up dissolved organic matter (DOM) characterization. This rapid and reliable approach minimizes pH adjustment time and laboratory workload.
Area of Science:
- Environmental Chemistry
- Analytical Chemistry
Background:
- UV-vis spectrophotometry is used to determine dissolved organic matter (DOM) acid-base properties.
- Traditional methods require slow, incremental pH adjustments, leading to time consumption and dilution effects.
Purpose of the Study:
- To introduce a novel "buffer method" for rapid pH adjustment in DOM acid-base titration.
- To validate the efficiency and reliability of the buffer method.
Main Methods:
- Utilizing carefully selected pH-buffers for rapid pH adjustments during acid-base titration.
- Statistical validation of the buffer method against traditional approaches.
Main Results:
- The buffer method significantly reduces pH adjustment time.
- The method is statistically validated, ensuring reliability.
- Laboratory workload is lightened compared to conventional techniques.
Conclusions:
- The buffer method offers a faster, more efficient alternative for DOM acid-base property characterization.
- This approach streamlines laboratory procedures.
- While chemical costs are slightly higher, the benefits in time and workload outweigh the increase.
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