AA2300 Atomic Absorption Spectrophotometer Accurately Determines Aluminum and Iron in Water Samples

Customer Background

A regional water quality monitoring laboratory is responsible for the routine testing of tap water, treated plant effluent and industrial utility water. With the implementation of China's Standards for Drinking Water Quality (GB 5749-2022), the laboratory must reliably verify aluminum at levels as low as 0.2 mg/L, while also monitoring iron as an indicator of taste complaints, staining and pipeline corrosion. The lab required a single, stable platform capable of delivering trace-level results in the low microgram-per-litre range, with excellent repeatability and full compliance documentation.

Why Aluminum and Iron Matter

• Aluminum is not an essential element for the human body. Excessive intake accumulates in the brain and bones and may raise the long-term risk of Alzheimer's disease, osteomalacia and anemia. Because water treatment plants widely use aluminum-salt coagulants, residual aluminum in finished water directly reflects whether coagulant dosing and pH control are correct.
• Iron is not itself toxic, but elevated iron produces a noticeable metallic taste, stains clothing and utensils, and can turn water brownish-red. In boiler and cooling water systems, iron ions typically originate from pipe corrosion; excess iron reduces heat-transfer efficiency, triggers localized corrosion and accelerates equipment wear.

Measuring both elements therefore serves two purposes: confirming drinking-water safety and evaluating corrosion risk for better overall water quality management.

Instrument Configuration

The laboratory selected the Wayeal AA2300 Atomic Absorption Spectrophotometer in a graphite furnace configuration, assembled as follows:

Aluminum and iron standard solutions of 1000 mg/L were used as stock standards, with the sample and calibration solvents kept matrix-matched throughout the sequence.

Calibration Performance

Both elements were calibrated with graphite furnace atomization over a working range of 10-50 µg/L. Every calibration point was injected in triplicate.

Absorbance increased linearly with concentration for both elements, and triplicate precision stayed comfortably below the 5% acceptance limit at every level, including the lowest 10 µg/L point.

Real Sample Results

The unknown water sample was analyzed without dilution and returned 10.7030 µg/L aluminum and 30.7031 µg/L iron - both far below the 0.2 mg/L regulatory limit for aluminum, yet quantified with four significant figures and no need for re-runs.

Results Summary

• Linear correlation coefficient r ≥ 0.999 for both aluminum and iron.
• Triplicate RSD < 5% across the entire working range.
• Trace levels of roughly 10 µg/L detected and quantified with confidence.
• Matrix-matched sample and standard solvents eliminated systematic bias.

Conclusion

The Wayeal AA2300 atomic absorption spectrophotometer, combined with the GF2310 graphite furnace, AS2310 autosampler and WY atom software, delivers an accurate, highly sensitive and repeatable method for aluminum and iron in water samples. The validated performance allows the laboratory to confirm compliance with GB 5749-2022, verify coagulant dosing and pH control at the treatment plant, and assess corrosion risk in boiler and cooling water circuits - all from a single, compact bench platform.

About Wayeal

Wayeal (Anhui Wayeal Technology) is based at No. 8 Wenqu Road, High-tech Zone, Hefei, Anhui, China, and supplies analytical instrumentation and application support for water, environmental, food and pharmaceutical laboratories. More application notes are available via www.wayeal.com.cn.