Determination of trace phosphate ion with 3,3',5,5'-tetramethylbenzidine using a flotation-extraction
Talanta
|October 31, 2008
Summary
This study introduces a new flotation-extraction method to improve spectrophotometry sensitivity for phosphate determination. The technique enhances sensitivity for analyzing phosphate in wastewater samples.
Area of Science:
- Analytical Chemistry
- Environmental Chemistry
Background:
- Spectrophotometry is a common analytical technique.
- Enhancing sensitivity is crucial for accurate trace element analysis, especially in environmental samples.
Purpose of the Study:
- To develop a novel flotation-extraction method for enhanced sensitivity in spectrophotometry.
- To determine phosphate concentrations in wastewater samples.
Main Methods:
- A flotation-extraction technique was developed.
- The method utilizes the reaction of molybdate, phosphate, and 3,3',5,5'-tetramethylbenzidine (TMB) in an acidic medium.
- The resulting charge transfer complex ion is extracted using DMSO-formic acid and analyzed via spectrophotometry.
Main Results:
- The apparent molar absorptivity achieved was 4.03x10(5) L mol(-1) cm(-1) at 458 nm.
- The method demonstrated high sensitivity for phosphate detection.
- The method was successfully applied to wastewater samples, yielding satisfactory results.
Conclusions:
- The proposed flotation-extraction method offers a simple and convenient approach for enhancing spectrophotometric sensitivity.
- This technique is effective for the accurate determination of phosphate in wastewater.
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