Automated flow-injection pseudotitration of boric acid

Area of Science:

• Analytical Chemistry
• Chemical Analysis

Background:

• Accurate determination of boric acid is crucial in various fields, including environmental monitoring and quality control of commercial products.
• Traditional titrimetric methods can be time-consuming and labor-intensive.

Purpose of the Study:

• To develop and validate an automated flow-injection pseudotitrimetric method for boric acid determination.
• To establish the analytical range, precision, and accuracy of the new method.

Main Methods:

• Utilized a flow-injection photometric analyzer controlled by a microcomputer.
• Employed a pseudotitrimetric approach involving the injection of samples into a flowing stream of mannitol-bromothymol blue.
• Measured peak width in time units for quantification.

Main Results:

• Achieved a wide analytical range for boric acid from 1.5-309 mg/100 mL.
• Demonstrated high precision with coefficients of variation (CV) between 0.1-0.4% (n=5).
• Recovery studies in mixtures yielded a mean of 99.8%, indicating excellent accuracy.

Conclusions:

• The automated flow-injection method provides a rapid, precise, and accurate alternative for boric acid determination.
• The method is suitable for analyzing commercial preparations and can be compared to classical titrimetric techniques.