Design and optimization of the native filling material supported passive samplers to be used in detection of micropollutants in water environment

In this study, a new passive sampling tool for waters was developed by using C18-Silica material produced with domestic facilities. As a result of the studies carried out by examining the passive sampler types in the literature, a completely native product has been developed as an alternative to these products. With this native product, it is aimed to sample and detect 16 polycyclic aromatic hydrocarbon (PAH) compounds, which are one of the organic micropollutant groups in waters and are on the priority pollutants list by the US Environmental Protection Agency (US-EPA). C18-silica, which is the adsorbent material to be used as the acceptor phase in the passive sampler, was synthesized from water glass using completely domestic sources. It has been determined that the native C18-silica material obtained is of suitable quality by comparing it with its equivalents in the market. It has been determined that the native C18-silica material is of similar quality by comparison with its counterparts in the market. A suitable design for the powder form has been created in order to the product whose synthesis phase has been completed can be used as a passive sampler. It was decided to use a two-phase design consisting of a low density polyethylene (LDPE) membrane, which will retain this material as well as the native adsorbent to be used as the acceptor phase and deliver the PAH compounds from the water environment to the adsorbent via semipermeability. The design of the native passive sampling system was completed by placing the two-phase sampler in a housing which was made from 316L stainless steel. The adsorption efficiency of the native sampler was determined in the experiments which carried out under certain and constant conditions in the laboratory environment. Dissolved PAH compounds in water with logKow between 4.5 and 6.8 were collected by the passive sampler at an efficiency of 78-89%. Laboratory experiments were continued with adsorption kinetic studies as a result of the high adsorption efficiency of the native passive sampler for the target analytes. The sampling rate (Rs) and the sampler-water partition coefficients (Ksw) for the native passive sampler were obtained for each analyte. Owing to the 2nd degree polynomial equation of this highly correlated curve, it has been obtained logKsw values for any compound which has a logKow value between 4.1 and 6.5 without the need for an experimental study specific to the native passive sampler. Theoretical half-time values (t1/2) to determine which regime (linear, curvilinear or equilibrium) the sampler is in, were calculated separately for each analyte by using the Rs and Ksw values obtained for the domestic passive sampler. In the studies, it was found out that the domestic passive sampler reached the equilibrium regime in approximately one week (average 8 days). In order to calculate time-weighted average concentration values in water from passive sampler results in field studies, the elapsed times in sampling were compared with the theoretical half-times, and the results were calculated using proper models for the selected regime. The native sampler results obtained at the Safiport station were compared with SPMD and spot sampling results. With this comparison, the both results of the native sampler and SPMD showed similar trends in general, and also it was seen that these results were close with the spot sampling results. It has been proven as a result of all laboratory and field studies that the native passive sampler can be used in the detection of PAHs. In addition, it has been shown once again that passive samplers can be used as supportive tools in pollution monitoring studies that will cover certain time periods.