Due to their good anti-corrosion properties, the use of benzotriazoles has been extensive in recent decades. As they are chemically stable, soluble in water and resistant to biodegradation, their environmental impact is also being increasingly explored. Like any introduced substance, benzotriazoles are not exactly beneficial to the natural environment. In particular, high concentrations are expected to be found around airports and on agricultural land using sewage sludge.
The purpose of the thesis was to develop an extraction method for the determination of six benzotriazoles in soil. I first extracted the benzotriazoles from the soil sample using ultrasonic solvent extraction followed by solid phase extraction (SPE). Then, the compounds were determined by high-performance liquid chromatography (HPLC). Finally, I tried the developed method on two real soil samples.
For ultrasonic extraction, I determined a mixture containing 10% MQ water and 90% acetone as the optimal solvent. I then determined the optimal ultrasonic extraction time. It turned out that 40 min on the ultrasound bath was the most optimal, since most of benzotriazoles were extracted in the highest proportion at this time. The final determination was whether the ultrasonic bath needed to be heated. The results showed that heating is not necessary, since there was no significant difference in the extraction efficiency by heating and at room temperature, and for some benzotriazoles, the efficiency while heating was even lower.
Real soil samples were taken from the vicinity of the Jože Pučnik Airport and from the vicinity of the white goods landfill at Vič. The results showed no content of benzotriazoles. They may not actually be present in the ground or their concentrations may be so low that they cannot be detected.
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