Strukturna i morfološka karakterizacija alginatnih gelova umreženih ionima Ca²⁺ i Fe³⁺ te njihovih čvrstih pirolitičkih produkata

master's thesis

• Title (english): Structural and morphological characterization of alginate gels crosslinked with Ca²⁺ and Fe³⁺ ions and their solid pyrolytic products
• Author: Ana Čoklica
• Mentor: Damir Iveković (mentor)
• Mentor: Egon Rešetar (pomoć pri izradi, neposredni voditelj)
• Committee member: Ivone Jakaša (predsjednik povjerenstva)
• Committee member: Tomislava Vukušić Pavičić (član povjerenstva)
• Committee member: Antonela Ninčević Grassino (član povjerenstva)
• Granter: University of Zagreb; Faculty of Food Technology and Biotechnology; (Department of Chemistry and Biochemistry); (Laboratory for General and Inorganic Chemistry and Electroanalysis); Zagreb
• Defense date and country: 2024-12-19, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Food Technology

Abstract

Alginat i alginatni hidrogelovi dobiveni umrežavanjem alginata s dvovalentnim kationima (najčešće Ca²⁺) već se desetljećima široko primjenjuju u prehrambenoj i farmaceutskoj industriji. U novije vrijeme intenzivno se istražuju alginatni hidrogelovi dobiveni ionotropnim geliranjem alginata viševalentnim kationima metala te njihovi pirolitički produkti, koji su se pokazali kao obećavajući materijali za primjenu u katalizi, adsorpciji, spremnicima energije te remedijaciji okoliša. U ovom radu istraženo je geliranje alginata u otopinama koje sadrže acetatne i citratne komplekse željeza(III), kako bi se utvrdilo može li se zakiseljavanjem otopine utjecati na koordinacijsku ravnotežu između iona Fe³⁺, karboksilatnog liganda i alginata na način da se kontroliranom promjenom pH postigne umrežavanje alginata. Također, istražene su strukturne i morfološke razlike između alginatnih gelova umreženih ionima Ca²⁺ i Fe³⁺ te čvrstih produkata njihove visokotemperaturne pirolize, s ciljem dobivanja informacija o morfološkim specifičnostima pirolitičkih ugljika dobivenih iz željezova(III) alginata.

Abstract (english)

Alginate and alginate hydrogels obtained by cross-linking of alginate with divalent cations (typically Ca²⁺) have been widely used in the food and pharmaceutical industry for decades. Recently, alginate hydrogels obtained by ionotropic gelation of alginate with multivalent metal cations and biochars derived from them have been intensively investigated due to their potential use as catalysts, adsorbents or in energy storage and environmental remediation. In this work, the gelation of alginate in solutions containing acetate and citrate complexes of iron(III) was investigated, in order to determine whether the acidity of the solution can affect the coordination equilibrium between the Fe³⁺ ions, carboxylate ligand and alginate in such a way that the cross-linking of alginate can be achieved by a controlled change of solution pH. Structural and morphological differences between alginate gels crosslinked with Ca²⁺ and Fe³⁺ ions, as well as their pyrolytic products, were also investigated, with the aim of gaining insight into the specific morphological characteristics of pyrolytic carbons prepared from iron(III) alginate.

• Keywords: alginat; ionotropno geliranje; željezo(III); acetato kompleks
• Keywords (english): alginate; ionotropic gelation; iron(III); acetato complex
• Language: croatian
• URN:NBN: urn:nbn:hr:159:637725
• Study programme: Title: Food Engineering; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka prehrambenog inženjerstva (magistar/magistra inženjer/inženjerka prehrambenog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2025-01-28 12:14:51