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Composites of clay and poly(vinyl alcohol) (PVA) were synthesized using different PVA loadings (10 wt.% and 20 wt.%). Glassy carbon electrode (GCE) was modified with the obtained samples using Nafion. Modified electrodes were used for the analytical detection of antimony. The influence of PVA on electrode sensitivity toward antimony was determined by comparison with the behavior of GCE modified with pure clay. The contribution of Nafion was assessed by testing GCE covered only with Nafion. The sensitivity of PVA/clay modified GCE for antimony was further enhanced by formation of poly(pyrogallol) film on electrode surface by electropolymerization. Electrode showed good repeatability and detection limit of 0.2 µM. The presence of Cu(II) in concentrations higher than 1 µM in Sb(III) solution interfered with electrode response towards Sb(III).

Predmet rada ove doktorske disertacije bio je sinteza i karakterizacija aminofunkcionalizovanog makroporoznog nanokompozita polimera i gline, koji je u laboratorijskim uslovima ispitan kao sorbens za uklanjanje derivata fenola iz vodenih rastvora. Nanokompozit poli(glicidilmetakrilata-ko-etilenglikoldimetakrilata) i kiselomodifikovanog bentonita dobijen je postupkom suspenzione kopolimerizacije preko slobodnih radikala. Zatim je nanokompozit funkcionalizovan reakcijom sa dietilentriaminom (deta). Funkcionalizacija je od ključnog značaja za sorpcionu sposobnost i selektivnost kompozita. Ispitivani kompozit je upoređen sa kopolimerom poli(glicidilmetakrilata-koetilenglikoldimetakrilatom). Urađena je karakterizacija nefunkcionalizovanih i funkcionalizovanih uzoraka (kopolimera i kompozita) hemijskom analizom, infracrvenom spektroskopijom, skenirajućom elektronskom mikroskopijom (SEM), transmisionom elektronskom mikroskopijom (TEM) i određivanjem teksturalnih svojstava. TEM analizom potvrđeno je da sintetisani kompozit ima nanokompozitnu strukturu i da se najbolje može opisati kao disperzija interkalisanih i razlistanih agregata u polimernoj matrici. Pored prisustva funkcionalnih grupa i teksturalna svojstva uzoraka su značajna za sorpcionu efikasnost. Uočeno je da se kod nanokompozita, za razliku od kopolimera, koji je dominantno makroporozan (sa prečnikom pora > 50 nm), javlja i značajan udeo mezopora (sa prečnikom pora od 2 do 50 nm). Prisustvo mezopora uslovljava da nanokompozit ima veću specifičnu površinu i ukupnu zapreminu pora. Određivanjem sadržaja amino grupa funkcionalizovanih uzoraka dobijena je nešto niža vrednost za kompozit u odnosu na kopolimer što može biti posledica manje dostupnosti epoksidnih grupa kod nanokompozita... Amino-functionalized macroporous polymer-clay nanocomposite was synthesized and fully characterized. This material was investigated under laboratory conditions as a sorbent for removal of phenol derivatives from water solutions. Nanocomposite of poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) and acid modified bentonite was prepared by radical suspension copolymerization and functionalized with diethylenetriamine (deta). The purpose of functionalization was to enable sorption and selectivity of the composite. Investigated composite was compared with copolymer poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate). Nonfunctionalized and functionalized samples (copolymer and composite) were characterized by chemical analysis, Infrared Spectroscopy, Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and their textural properties were determined. TEM analysis confirmed that the synthesized composite had nanocomposite structure which can be best described as a dispersion of intercalated and exfoliated aggregates in polymeric matrix. Besides functional groups, textural properties of samples are also important for sorption efficiency. It was observed that besides macropores (pore diameter: > 50 nm) which are characteristics of copolymers, nanocomposite contained a significant amount of mesopores (pore diameter: 2-50 nm). The presence of mesopores led to higher specific surface area and total pore volume of nanocomposite. The content of amino groups in the functionalized composite (CP-SA-deta) was slightly lower than in the functionalized copolymer (CP-deta). This could be the consequence of the lower accessibility of epoxy groups in CP-SA-deta...

Predmet rada ove doktorske disertacije bio je sinteza i karakterizacija aluminijumom pilarenih glina impregnisanih kobaltom i ispitivanje dobijenih materijala kao katalizatora u procesu katalitičke oksidativne degradacije model zagađujuće materije vode u prisustvu oksona kao izvora sulfatnih radikala. Azo boja tartrazin je izabrana kao model zagađujuće materije u vodi, čija je katalitička degradacija ispitivana... The main objective of this doctoral dissertation was to synthesise and characterize cobalt impregnated aluminium pillared clays and to test them as catalysts in catalytic oxidative degradation of a model water pollutant in the presence of oxone as a source of sulfate radicals. Azo-dye tartazine was chosen as the model pollutant in wastewaters to be investigated in the catalytic oxidative degradation...