Historically, chemical analysis of water was achieved by titration methods. It is, practically, impossible to use these on water containing a pollutant at a low concentration due to the need to collect a very large volume of water that can be concentrated to permit a weighable amount of chemical to be obtained at the end of the procedure. Also, such procedures are very time-consuming and operator sensitive. Therefore, modern analysis is based on electrical, atomic and spectrographic techniques.
The most common analytical techniques suitable for determination of the presence of selected pollutants are synthesised in Table 7.3.
Table 7.3 Analytical techniques suitable for determination of the presence of selected pollutants
* = include sodium, potassium, calcium, barium and magnesium. X = include iron, copper, zinc, cadmium, lead, chromium, nickel, cobalt and vanadium. f = here include rhodium, palladium, iridium and platinum. PAH = polyaromatic hydrocarbons, HCB = hexachlorobenzene, PCB = polychlorinated biphenyls. ppm = parts per million (10-6). ppb = parts per billion (10-9). ppt = parts per trillion (10-12). |