TOC and TN Evaluation of Hydrogen Peroxide Solution

Significance of the Topic

Hydrogen peroxide is a key oxidant and disinfectant that decomposes into water and oxygen, making it an eco-friendly choice for diverse industries. In high-purity fields such as semiconductor cleaning, controlling organic carbon and nitrogen impurities is critical. A robust analytical approach for simultaneous quantification of TOC and TN in concentrated hydrogen peroxide enhances quality assurance and process safety.

Objectives and Overview

This study demonstrates a rapid, simultaneous method for determining total organic carbon (TOC) and total nitrogen (TN) in 30% hydrogen peroxide solutions without sample dilution. Incorporation of an automatic sampler streamlines the analysis of multiple samples, supporting stringent purity requirements in industrial settings.

Methodology and Instrumentation

• Analyzer Setup: Shimadzu TOC-L Total Organic Carbon Analyzer coupled with TNM-L Total Nitrogen Unit.
• Sample Introduction: ASI-L auto-sampler for automated handling of multiple samples.
• TOC Measurement: Non purgeable organic carbon (NPOC) method, removing inorganic carbon via sparging and direct measurement of total carbon.
• TN Measurement: Catalytic conversion of nitrogen species to nitric oxide followed by detection.
• Calibration: Two-point curves using 0 and 20 mgC/L potassium hydrogen phthalate for TOC and 0 and 20 mgN/L potassium nitrate for TN, with origin shift correction.
• Sample Preparation: Spiking 30% hydrogen peroxide with 1, 5, and 10 mg/L of carbon (via potassium hydrogen phthalate) and nitrogen (via potassium nitrate).

Key Results and Discussion

The method achieved recovery rates above 96% for both TOC and TN across all spiked concentrations. Linear correlations between added and measured values yielded a correlation coefficient of 1.000, confirming method accuracy. Detailed peak profiles validated the precision of both TOC and TN determinations at low concentration levels (approximately 1 mg/L).

Benefits and Practical Applications

• Simultaneous TOC and TN analysis without dilution of high-strength hydrogen peroxide preserves sample integrity and reduces preparation time.
• High-speed measurement increases laboratory throughput, especially when combined with an automatic sampler.
• Application in semiconductor manufacturing and other industries requiring ultra pure reagents for contamination monitoring.

Future Trends and Applications

Advancements may include integration of inline monitoring for real-time quality control, coupling with mass spectrometry for speciation studies, and further sensitivity enhancements to detect sub mg/L impurities. Automation and data connectivity will support Industry 4.0 efforts in continuous process analytics.

Conclusion

The combined TOC-L and TNM-L system facilitates accurate, efficient, and simultaneous quantification of organic carbon and nitrogen in concentrated hydrogen peroxide. This approach meets rigorous quality control demands and aids in maintaining chemical purity across various industrial sectors.