Removal of selected heterocyclic organic compounds from water and possibilities of system optimization

Benzotriazoles (BTs) harm the life of organisms due to their chemical, physical and biological properties. It is essential to remove them from the natural environment without introducing additional chemical compounds into it. Benzotriazoles are difficult to remove from water because they are resistant to classic technological processes used for water treatment, for example, chlorination, biodegradation, or ozonation. To extend the methods of removing benzotriazoles from water, a membrane process was used - nanofiltration. The research was carried out at a small nanofiltration station with a spiral aromatic polyamide membrane. Four compounds were selected for the study: 1H-benzotriazole (BT), 4-methyl-1H-benzotriazole (4MBT), 5-methyl-1H-benzotriazole (5MBT), and 5-chlorobenzotriazole (5ClBT). The tests were carried out using surface water enriched with a standard solution of the tested compounds. As a result of the research carried out at this stage, data were obtained which indicate the dependence of the treatment efficiency on the transmembrane pressure.