Synthesis of macroporous beads based on ion-charged monomers using multiple-emulsion-templating and their use as adsorbents for the heavy metals removal

V magistrski nalogi smo sintetizirali visokoporozne polielektrolitne polimere v obliki monolitov in kroglic, imenovane poliHIPE materiali. PoliHIPE monolite smo pripravili z emulzijsko polimerizacijo, medtem ko smo kroglice pripravili s sedimentacijsko polimerizacijo multiplih emulzij. Oba tipa polielektrolitnih adsorbentov sta bila na osnovi 2-akrilamido-2-metilpropansulfonske kisline (AMPS) in akrilamida (AAM). Prisotnost porozne morfologije smo analizirali z elektronsko vrstično mikroskopijo (SEM), kemijsko in elementno sestavo pa z infra-rdečo (FTIR) spektroskopijo in elementno analizo. V nadaljevanju smo raziskali adsorpcijske lastnosti in kinetiko adsorpcije PAMPS poliHIPE materialov. Preučevali smo, kako oblika (monolit v primerjavi s kroglicam), količina ionskih skupin (PAMPS 100 in PAMPS 50) ter poroznost vplivajo na adsorpcijske procese. Za primerjavo vpliva poroznosti, smo uporabili ne-porozne, komercialno dostopne kroglice na osnovi sulfoniranega polistirena. Pripravili smo modelne raztopine cinkovih (Zn(NO3)2), železovih (Fe(NO3)3) in aluminijevih (Al(NO3)3) ionov, ter spremljali proces adsorpcije kot funkcijo časa. Za ta namen smo uporabili emisijsko atomsko spektrometrijo (FAAS). Izkazalo se je, da spremenjeno število ionskih skupin ni tako zelo vplivalo na hitrost adsorpcije, saj je bila le-ta zelo podobna pri obeh tipih monolita (PAMPS 100M in PAMPS 50M) kot tudi kroglic (PAMPS 100K in PAMPS 50K). Rezultati so pokazali, da sta oblika in poroznost vplivala na hitrost adsorpcije. Adsorpcija v primeru kroglic je potekla hitreje kot pri uporabi monolita (vpliv oblike), prav tako pa je bila adsropcija hitrejša v primeru poroznih kroglic kot pri neporoznih komercialnih kroglicah (vpliv poroznosti). S pomočjo enačb za linearizirana modela psevdo-prvega reda in psevdo-drugega reda, smo določili po katerem modelu je potekala adsorpcija vsakega adsorbenta v vseh treh raztopinah kovin. Adsorpcijske lastnosti in kinetiko adsorpcije smo spremljali tudi pri višjih temperaturah, 35 °C in 50 °C ter izračunali kateremu kinetičnemu modelu sledijo.In the master thesis, we synthesized highly porous polyelectrolyte polymers in the form of monoliths and beads, also called polyHIPE materials. PolyHIPE monoliths were prepared through high internal phase emulsion polymerization. Both types of polyelectrolyte adsorbents were based on 2-acrylamido-2-methylpropane sulfonic acid (AMPS) and acrylamide (AAM). The morphology of the adsorbent thus obtained was analysed by scanning electron microscopy (SEM), while the chemical and elemental composition was studied by FTIR and elemental analysis. Next, we investigated the adsorption properties and adsorption kinetics of the adsorbents thus prepared. We checked how the shape (monolith vs. beads), the number of ionic groups (PAMPS 100 and PAMPS 50) and the porosity affected the adsorption processes at room temperature. To compare the effect of porosity on adsorption, the nonporous commercial beads based on sulfonated polystyrene were also used and analysed. We prepared model solutions of zinc (Zn(NO3)2), iron (Fe(NO3)3), and aluminium (Al(NO3)3) metal ions and then observed the adsorption process as a function of time. It turned out that the number of ionic groups did not affect the adsorption rate, as it was very similar for both types of monoliths (PAMPS 100M and PAMPS 50M) and beads (PAMPS 100K and PAMPS 50K). But the results showed that shape and porosity influenced the adsorption rate, i.e. adsorption was faster for beads than for monoliths (shape effect) and compared to commercial nonporous beads (porosity effect). Equations for linearized models, pseudo-first order and pseudo-second order were used to determine which model the adsorption kinetics follows for each adsorbent in all three metal solutions. Finally, the adsorption properties and adsorption kinetics were also monitored at higher temperatures, 35 °C and 50 °C, and it was calculated which kinetic model they follow