Determination of Iron Concentration in Drinking Water Using Visible Spectrophotometry

Abstract

This research investigates the quantitative determination of iron concentrations in drinking water samples using visible spectrophotometry, specifically employing the 1,10-phenanthroline method. Iron is an essential micronutrient; however, elevated levels in drinking water led to aesthetic issues, such as metallic taste and reddish-brown staining, and may pose long-term health risks or indicate infrastructure corrosion. The primary objective of this study was to assess the accuracy of spectrophotometric analysis in detecting iron within the limits prescribed by the World Health Organization (WHO) and local environmental standards. The methodology involved the formation of a stable, orange-red complex between ferrous iron (Fe2+) and 1,10-phenanthroline, measured at an absorption maximum of 510 nm. A comprehensive calibration curve was established, demonstrating high linearity (R2>0.99), which allowed for the precise quantification of iron in various water sources, including tap water and groundwater. The results indicated that while most samples remained within the recommended limit of 0.3 mg/L, certain groundwater sources exhibited higher concentrations, necessitating the implementation of sequestration or filtration techniques. The discussion evaluates the chemical interferences, such as the presence of phosphates or other heavy metals, and suggests protocols for sample pre-treatment to ensure analytical integrity. This paper concludes that visible spectrophotometry remains a robust, cost-effective, and highly reliable technique for routine water quality monitoring. It provides a foundation for developing sustainable water management strategies and emphasizes the importance of continuous chemical surveillance to safeguard public health and ensure the delivery of high-quality potable water.