Alternative method for qualitative analysis of specific non-volatile organic compounds present in South African water systems

Abstract

Currently, water quality assessment has become a necessity in order to maintain healthy living. Point and non-point sources of water pollutants are either organic or inorganic in nature. Non-volatile organic compounds (nVOCs) mostly exist as solids at room temperature and are used on a large scale in most chemical industries. Since these nVOCs are toxic to both animals and humans and some of these non-volatile organic compounds are carcinogenic, it is important to analyze the water in order to ascertain its quality by identifying which types of compounds are present in these systems and quantifying them. This work reports on the use of a new and alternative method for qualitative analysis of nVOCs in water systems. Analysis was done for 13 sampling sites (seven from wastewater and six from surface water found in Gauteng and KwaZulu-Natal provinces, respectively). Vacuum evaporation followed by methanol extraction of the residues was performed. Fourier Transform Infrared (FTIR) was conducted using NaCl disc and KBr pellets and their results compared. High Performance Liquid Chromatography (HPLC) was chosen as a technique for comparison and to prove that the simple infrared (IR) can be used instead. In addition, HPLC is an ideal analytical technique for non-volatile substances.

Untitled

“…Determination of the functional group in the samples were analyzed through Fourier Transform -Infrared spectro photometer (FT-IR).For liquid samples about 0.1 ml of the solution was spared over sodium chloride plates to form a thin film and observed under FT-IR spectrophotometer the spectrum was recorded between 400 -4000 cm -1 and matched with the library data for functional group conformation 9 .…”