Application of polyisobutylene in the treatment of water

A new procedure for (1) the extraction and (2) the quantitative measurement of aromatic hydrocarbons from contaminated water is described. Solutions of polyisobutylene in isooctane (PIB/ISO) were prepared in three different concentrations at room temperature. The substrates: benzene, toluene, ethylbenzene, and xylene were extracted by the prepared polyisobutylene solutions. An aqueous stock solution of toluene, benzene, ethylbenzene and xylene, containing 150 ppm of each compound was prepared. Additionally, a toluene aqueous stock solution containing 500 ppm was made. In order to develop Beer-Lambert curves of the infrared (IR) absorption of each hydrocarbon these stock solutions were used to prepare standard solutions by dilution with pure water. Twenty five ml of hydrocarbon solution were transferred to a separatory funnel and 25 ml of PIB/ISO were poured into the funnel. The funnel was shaken gently for five minutes. The two layers, water and PIB/ISO, were separated immediately after the extraction. The aqueous sample was collected in a graduated cylinder. Two ml of sample were transferred from the graduated cylinder to a 1 cm quartz cuvette. The quartz cuvette was placed in an air remover apparatus for one minute to remove bubbles from the solution. In order to create the standards curves, the IR absorption of the hydrocarbons in the aqueous solutions was measured in a Bio-Rad SF7 Fourier Transform Infrared (FTIR) spectrometer and the data was stored on the hard disc. The quantitation was carried out using the Bio-Rad 2.21 software program. The single-pass extraction process was very efficient and the new analytical procedure was more sensitive than EPA Method 413.2 but does not require the use of Freon.