Which method is commonly used to analyze metals in wastewater?

Atomic Absorption Spectroscopy is widely used for analyzing metals in wastewater due to its capability to detect trace levels of metal ions with high sensitivity and selectivity. This method involves the absorption of light by free atoms in the gaseous state. It utilizes a light source specific to the metal being analyzed, typically a hollow cathode lamp, which emits light at wavelengths characteristic of the element. When a sample is atomized and the light beam passes through it, the amount of light absorbed by the metal ions in the sample gives a direct correlation to the concentration of those metals.

This method is especially advantageous for wastewater analysis because it can handle complex matrices and provide quick results, making it suitable for routine monitoring. Additionally, the selectivity of Atomic Absorption Spectroscopy allows for the direct measurement of many metals without extensive sample preparation, which is often a requirement for other analytical methods.

It is important to note that while other techniques like Mass Spectrometry can also analyze metals, they are typically used in conjunction with other processes or for different applications. Gas Chromatography and Ultraviolet Spectroscopy are not suitable for direct metal analysis in wastewater as they focus on different types of compounds, such as organic chemicals and UV-absorbing substances, respectively.