magistrsko delo
Urška Ostroško (Avtor), Matjaž Kristl (Mentor), Irena Ban (Komentor)

Povzetek

V okviru magistrskega dela smo sintetizirali magnetne nanodelce kot potencialno gonilno raztopino za proces direktne osmoze (FO). S postopkom soobarjanja smo sintetizirali nanodelce magnetita (Fe3O4) in jih stabilizirali s (3-aminopropil) trietoksisilanom (APTES). APTES se na delce veže preko silanolnih skupin, amino skupine pa ostanejo proste za nadaljnjo funkcionalizacijo. Preko tvorbe amidne vezi smo nanje vezali različne količine citronske kisline (CA) ter poliakrilne kisline (PAA), da bi dosegli čim višji osmotski tlak. Da je reakcija vezave potekla, smo dodali zamreževalec 1-etil-3-(3-dimetilaminopropil) karbodiimid hidroklorid (EDC), pri poliakrilni kislini pa tudi N-hidroksisukcinimid (NHS), ki stabilizira intermediat. Nanodelce Fe3O4/APTES, Fe3O4/APTES/CA in Fe3O4/APTES/PAA smo karakterizirali z različnimi metodami. S termogravimetrično analizo (TGA) smo določili količino organskih snovi (APTES, CA, PAA) na površini nanodelcev, z dinamičnim sipanjem svetlobe (DLS) smo določili izoelektrično točko, zeta potencial in velikost delcev v suspenziji, dejansko velikost nanodelcev pa nam je dala analiza s presevnim elektronskim mikroskopom (TEM). Karakteristični vrhovi pri infrardeči spektroskopiji s Fourierjevo transformacijo (FTIR) so nam potrdili vezavo APTES, CA in PAA. Določali smo osmotski tlak, s konduktometrično titracijo pa smo želeli določit količino prostih -COOH skupin. Najvišji osmotski tlak smo določili pri vzorcu z 0,8 g dodane citronske kisline (28,01 bar) ter vzorcu, kjer smo poliakrilno kislino dodali v razmerju 1:1 (27,12 bar). Sintezni postopek slednjega vzorca smo zato ponovili ter vzorec uporabili kot gonilno raztopino (DS) za poskusni proces direktne osmoze z deionizirano vodo kot vhodno raztopino (FS).

Ključne besede

magnetni nanodelci;magnetit;citronska kislina;poliakrilna kislina;direktna osmoza (FO);magistrske naloge;

Podatki

Jezik: Slovenski jezik
Leto izida:
Tipologija: 2.09 - Magistrsko delo
Organizacija: UM FKKT - Fakulteta za kemijo in kemijsko tehnologijo
Založnik: [U. Ostroško]
UDK: 620.3:66.081.63(043.2)
COBISS: 77461763 Povezava se bo odprla v novem oknu
Št. ogledov: 332
Št. prenosov: 58
Ocena: 0 (0 glasov)
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Ostali podatki

Sekundarni jezik: Angleški jezik
Sekundarni naslov: Synthesis and characterization of Fe3O4/APTES/CA and Fe3O4/APTES/PAA functionalized nanoparticles
Sekundarni povzetek: In the master's thesis, we synthesized magnetic nanoparticles as a potential draw solution for forward osmosis (FO). Magnetite (Fe3O4) nanoparticles were synthesized by the co precipitation process and stabilized using (3-aminopropyl) triethoxysilane (APTES). APTES binds to the particles via silanol groups, while amino groups can be further functionalized. In order to achieve the highest possible osmotic pressure, various amonuts of citric acid (CA) and polyacrylic acid (PAA) were added to form amide bond with amino groups. For the coupling reaction, crosslinker 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) was added. N hydroxysuccinimide (NHS) was used in the case of PAA to stabilize the intermediate. Fe3O4/APTES, Fe3O4/APTES/CA and Fe3O4/APTES/PAA nanoparticles were characterized by different methods. The amount of organic matter (APTES, CA, PAA) on the surface of nanoparticles was determined by thermogravimetric analysis (TGA); the isoelectric point, zeta potential and particle size in suspension were determined by dynamic light scattering (DLS); and the actual size of nanoparticles was given by transmission electron microscope (TEM) analysis. Characteristic peaks of Fourier transform infrared spectroscopy (FTIR) confirmed the binding of APTES, CA and PAA. Osmotic pressure was measured and the amount of free -COOH groups was determined by conductometric titration. The highest osmotic pressure showed sample with 0,8 g citric acid added (28.01 bar) and sample where polyacrylic acid was added in 1:1 ratio (27.12 bar). Synthesis of the latter sample was therefore repeated and the sample was used as draw solution (DS) in experimental forward osmosis with deionized water as feed solution (FS).
Sekundarne ključne besede: magnetic nanoparticles;magnetite;(3-aminopropyl)triethoxysilane (APTES);citric acid;polyacrylic acid;forward osmosis (FO);
Vrsta dela (COBISS): Magistrsko delo/naloga
Komentar na gradivo: Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Strani: XII, 56 str.
ID: 13280108