Površinska svojstva i otapanje fluorita

master's thesis

• Title (english): Surface properties and dissolution of fluorite
• Author: Ana Jurković
• Mentor: Tajana Begović (mentor)
• Committee member: Tajana Begović (predsjednik povjerenstva)
• Committee member: Adriana Kenđel (član povjerenstva)
• Committee member: Željka Soldin (član povjerenstva)
• Committee member: Davor Kovačević (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2023-02-24, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Kinetika otapanja (100), (110) i (111) plohe fluorita u vodi praćena je potenciometrijski mjerenjem koncentracije Ca2+, F– i H+ iona u otopini ion-selektivnim elektrodama tijekom 84 dana otapanja. Tenziometrijom i mikroskopom atomskih sila praćen je utjecaj otapanja na promjenu močivosti površine i topografiju (100), (110) i (111) ploha fluorita mjerenjem kontaktnog kuta i faktora hrapavosti prije i nakon otapanja. Površinski potencijal (100), (110) i (111) plohe monokristala fluorita tijekom 24 sata otapanja mjeren je fluoritnim monokristalnim elektrodama, a elektrokinetički potencijal nanočestica fluorita tijekom 37 dana otapanja određen je mjerenjem elektroforetske pokretljivosti nanočestica fluorita. Istražen je i utjecaj H+, OH–, F– i Ca2+ iona na elektrokinetički potencijal nanočestica fluorita. Metodama statičkog i dinamičkog raspršenja svjetlosti određen je hidrodinamički promjer i promjer giracije nanočestica fluorita. Određeni su koeficijenti brzine difuzije iona u otopinu za (100), (110) i (111) plohu te iznose: 0,005 s–1
; 0,045 s–1 i 0,03 s–1.

Abstract (english)

Ion selective electrodes were used to study dissolution kinetics of (100), (110) and (111) fluorite crystallographic planes by measuring Ca2+, F– and H+ ion concentration in the solution. Tensiometry and atomic force microscopy were employed for measuring dissolution impact on contact angle and surface roughness of specified fluorite crystallographic planes. Surface potential change of mentioned fluorite crystallographic planes during 24 hours of dissolution was investigated using a single crystal electrode. The electrokinetic potential of fluorite nanoparticles during dissolution was determined by measuring electrophoretic mobility. The influence of H+, OH–, F– i Ca2+ ions on the electrokinetic potential of fluorite nanoparticles was also investigated. The hydrodynamic diameter and diameter of gyration of fluorite nanoparticles were determined using static and dynamic light scattering methods. The ion diffusion rate coefficients in the solution for (100), (110) and (111) planes were obtained: 0.005 s–1, 0.045 s–1 and 0.03 s–1 respectively.

• Keywords: elektrokinetički potencijal; fluorit; hrapavost; kontaktni kut; monokristalne elektrode; otapanje; površinski potencijal
• Keywords (english): contact angle; dissolution; elektrokinetic potential; fluorite; roughness; surface potential; single crystal electrode
• Language: croatian
• URN:NBN: urn:nbn:hr:217:402022
• Project: Number: IP-2020-02-9571; Title: Fizikalna kemija procesa na međupovršini mineral/otopina (poli)elektrolita; Title: Physical chemistry of processes at mineral/(poly)electrolyte solution interface; Acronym: POLYMIN2; Leader: Tajana Begović; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Embargoed access; Embargo expiration date: 2024-08-24
• Created on: 2023-03-30 11:43:46