Nickel determination using automated photometric titration

Importance of the topic

Determining nickel concentrations accurately is critical in industrial quality control, environmental monitoring and the production of plating baths. Automated photometric titration streamlines analysis, reduces operator variability and improves throughput, making it well-suited for routine laboratory workflows.

Objectives and study overview

This application note describes a fully automated EDTA titration method for nickel in alkaline solutions. The key goals are to demonstrate endpoint detection via photometric measurement with murexide indicator at 574 nm, evaluate method precision and highlight automation benefits using specialized titration equipment.

Methodology

Sample: 5 mL of nickel solution (nominally 0.05 mol/L) diluted with 90 mL deionized water in a 200 mL beaker.
Reagents: 5 mL pH 10 ammonium buffer and 5 mL murexide indicator solution.
Titrant: 0.1 mol/L disodium EDTA solution.
Procedure: Automated addition of titrant in 0.05 mL increments under continuous stirring until a 15 mV photometric potential jump indicates the equivalence point.

Instrumentation used

• 907 Titrando system
• 815 Robotic USB Sample Processor XL
• 786 Swing head with swing arm
• Optrode photometric sensor (574 nm)
• Four dosage units (5, 10, 10 and 50 mL)
• Magnetic stirrer unit and disposable 200 mL PP beaker

Main results and discussion

Six replicate determinations yielded a mean nickel concentration of 2.95 g/L with a relative standard deviation of 0.36%. The sharp photometric endpoint facilitated by murexide and the Optrode detector ensures reliable equivalence-point recognition and minimal operator intervention.

Benefits and practical applications

• High precision and low reagent consumption through automated dosing.
• Improved reproducibility by minimizing manual handling.
• Fast turnaround suitable for high-throughput quality control.
• Adaptability to various sample matrices in industrial and environmental labs.

Future trends and potential applications

Integrating photometric titration with laboratory information management systems (LIMS) will further streamline data handling. Miniaturized sensor designs and new indicator dyes may extend the approach to trace-level metal analysis. Multi-element titration routines and hybrid techniques combining photometry with electrochemical detection represent promising developments.

Conclusion

The automated photometric titration method for nickel offers a robust, precise and efficient solution for routine analysis. Its ease of use and reliable endpoint detection make it an excellent choice for laboratories demanding high sample throughput and consistent quality.

Reference

Application Note T-150: Nickel determination using automated photometric titration