Removal of pharmaceuticals with RO/NF membranes from MilliQ water in alkali conditions

Lijekovi imaju važnu ulogu u liječenju i prevenciji bolesti u ljudi i životinja, zbog čega njihova prisutnost u okolišu svakodnevno raste. Većina farmaceutika ispušta se kontinuirano putem kanalizacijskog sustava, te ih je zbog njihovog negativnog utjecaja na okoliš neophodno učinkovito ukloniti. Ovaj rad ispitivao je učinkovitost i mehanizam uklanjanja farmaceutika (sulfagvanidin, trimetoprim, hidrokortizon i albendazol) reverzno osmotskim (RO) i nanofiltracijskim (NF) membranama (XLE, NF i NF270) iz ultra čiste vode u lužnatim uvjetima. Najveću učinkovitost uklanjanja pokazala je RO XLE membrana. Dominantan mehanizam uklanjanja farmaceutika bio je isključenje veličinom, no utjecaj na učinkovitost uklanjanja imale su i elektrostatske interakcije, te fizikalno-kemijske karakteristike membrana i farmaceutika. Rezultati FTIR analize pokazali su postojanje interakcija između membrane i farmaceutika, osim kod sulfagvanidina. Uočeno je da povećanjem hidrofobnosti organske komponente interakcije postaju izraženije. Utjecaj farmaceutika na membranski poliamidni sloj uočen je i u promjenama vrijednosti kontaktnog kuta i zeta potencijala.The drugs have an important role in the treatment and prevention of diseases in humans and animals, which means that their presence in the environment is increasing everyday. Most pharmaceuticals released continuously through the sewer system and because of their negative impact on the environment it is necessary to remove them effectively. This study examined the retention and removal mechanism of pharmaceuticals (sulfaguanidine, trimethoprim, hydrocortisone and albendazole) with reverse osmosis (RO) and nanofiltration (NF) membranes (XLE, NF and NF270) from MilliQ water in alkali conditions. The highest removal efficiency showed XLE RO membrane. Dominant rejection mechanism of the examined pharmaceuticals was the size exclusion, but electrostatic interactions and physico-chemical characteristics of the membrane and pharmaceuticals also had an impact. Results of FTIR analysis proved the existence of interaction between the membrane and pharmaceuticals, except for sulfaguanidine. It has been observed that interactions become more pronounced by increasing the hydrophobicity of the organic compounds. The impact of pharmaceuticals on the membrane polyamide layer also has been noticed in changes of the contact angle and zeta potential