PURELAB® Chorus 1 The Efficient Use of Ultraviolet (UV) Light

Importance of the Topic

Ultrapure water is essential for many analytical and life science applications due to its sensitivity to organic and biological contaminants.
Shortwave UV treatment at 185 nm and 254 nm wavelengths offers effective bacterial control and total organic carbon (TOC) reduction, which are critical for ensuring reliable experimental results and protecting instrumentation.

Study Objectives and Overview

The technology note introduces the use of dual-wavelength UV lamps in the PURELAB Chorus 1 system, focusing on minimizing TOC and microbial load in water purification.
It reviews the principles of UV action, monitoring strategies for impurities, and operational guidelines to maintain lamp performance.

Methodology and Monitoring Parameters

The note emphasizes the selection of parameters that can:

• Respond to a broad range of impurities
• Be measured rapidly and continuously
• Offer sufficient sensitivity and stability

Electrical resistivity is used to monitor ionic contaminants, while in-line TOC measurement addresses organic levels.
Other impurities such as particles, bacteria, endotoxins, bioactive species, and dissolved gases are controlled through filtration, UV photo-oxidation, ultrafiltration, and vacuum degassing.

Used Instrumentation

The PURELAB Chorus 1 system integrates a dual 185 nm/254 nm UV lamp.
The 254 nm emission disrupts nucleic acids to control microbes, while the 185 nm output oxidizes organic compounds to lower TOC.
Built-in resistivity and TOC sensors provide continuous real-time monitoring of ions and organics.

Main Results and Discussion

Dual-wavelength UV treatment demonstrates high germicidal efficiency and effective organic oxidation.
Maintaining lamp output above 80 % efficiency is crucial, as degradation affects both microbial control and TOC reduction.
Monitoring lamp transmissivity and replacing lamps annually ensures consistent performance.

Benefits and Practical Applications

• Continuous in-line monitoring allows immediate detection of contamination spikes.
• Dual UV wavelengths provide comprehensive treatment for both organics and microorganisms.
• Integrated sensors reduce the need for off-line testing and enhance laboratory workflow efficiency.

Future Trends and Opportunities

Advances in UV lamp materials and real-time sensor technologies are expected to further improve lamp lifespan and monitoring accuracy.
Integration of predictive maintenance algorithms and IoT connectivity may enable smarter purification systems with automated alerts and performance optimization.

Conclusion

Dual-wavelength UV purification combined with continuous resistivity and TOC monitoring offers a robust solution for maintaining ultrapure water quality.
Regular lamp maintenance and targeted control methods for non-organic impurities are essential to guarantee consistent water purity for sensitive analytical and research applications.