Category - Mercury-testing
Mercury Analysis in Water – Cleaning your containers
For trace element analysis in order to clean your containers, a common practice is to soak the containers in nitric acid. Acid bath is very commonly used in many labs however this is not suitable for mercury analysis at pg/g level. The mercury level in the acid bath can be a few thousand times higher than in the sample. By soaking your containers in the acid bath, the labels, the pen marks, the entire exterior will contaminate the bath and further contaminate other containers. The acidic vapour generated by the acid bath will also pollute the air or corrode the instruments in the lab. An easy way to clean the containers is to top up the container with deionized water to almost full, then add small amount of hydrochloric acid and bromide/bromate solution. Bear in mind that this procedure should be done in the fume cupboard. After adding the chemicals, fill the container up to the neck with deionized water then cap it tightly. Let it soak overnight. In the next morning, or before you need to use it, use weak reductant to decolorize the solution inside the containers, then wash the container with clean deionized water. Your container is now clean and ready for use.
Atomic Fluorescence Spectroscopy
The energy stored in atoms can be released in a variety of ways. When it is released as light, this is known as fluorescence. Atomic fluorescence spectroscopy (AFS) measures this emitted light. The wavelength of the emitted light tells you the identity of the atoms. The intensity of the fluoresced light is directly proportional to the concentration of atoms and the intensity of the excitation source. Atomic fluorescence is generally much more sensitive than atomic absorption. Read More