Ethanolamines are widely used in power industry cooling waters as carbon dioxide scrubbers. It is also used for the production of emulsifying agents, for gas purifications (for the removal of acidic components), and as corrosion inhibitors. Carryover of amines from scrubber units into waste streams can cause severe problems in refinery waste-treating pools. Different amines are sometimes used in different production areas to make it easier for plant operators to locate sources of amine contamination. It is now possible to easily and rapidly analyse amines by non suppressed Ion exchange chromatography without gradient.

Suppressed conductivity detection is a well-developed method for detecting charged species. Reversed-phase high-performance liquid chromatography (RP-HPLC) is a well developed method of separating substances on the basis of hydrophobicity. There are some situations where it is advantageous to use these two methods together. Perfluoro-acids (PFOAs) are one class of compounds that are ionic, hydrophobic and have low UV absorbance and are, therefore, suited to this combination.

Phthalates, a class of esters of 1,2-benzenedicarboxylic acid, are used for improving the pliability of plastics, plus have uses in the cosmetics industry. Their manufacture has increased rapidly, reaching an estimated half a billion kilograms per year, but with rising concerns of low level environmental contamination. In particular, recent analyses have shown that male reproductive development is sensitive to low levels of some phthalates.

According to US EPA 300.1 methodology, Part A requires analysis of seven common anions (fluoride, chloride, nitrite-N, bromide, nitrate-N, phosphate-P and sulphate) and Part B requires analysis of disinfectant by-products (chlorite, chlorate, bromide and bromate). Bromide analysis is included in both the parts of the method because of its critical role as a disinfectant by-product precursor. A surrogate standard dichloroacetic acid (DCA) is used for analytical procedure verification. Currently as per method (rev 1.0, 1999) 40 μL (Part A) and 200 μL (Part B) of sample is analysed on two separate columns. For high throughput laboratories, it is two separate methods and double the workload. This application note demonstrates combining of two separate applications into one single isocratic analysis.

Recent years have seen an increase in the monitoring of pharmaceutical residues in environmental water samples. A significant number of contaminants from common drug classes with analytes at very low concentrations have been reported to be present in rivers, streams and drinking water in both Europe and the US. Common classes including cholesterol-lowering drugs, antibiotics, analgesics, antiseptics and beta-blockers have been detected.