Karakterizacija vzorcev kalijevega bis(oksalato)kuprata(II) dihidrata, sušenih pri različnih temperaturah

Gliha, Hana (author), Čelan Korošin, Nataša (mentor)

V diplomskem delu sem preučevala, kako temperatura sušenja (50 °C ali 70 °C) vpliva na strukturo in sestavo kalijevega bis(oksalato)kuprata(II) dihidrata, ki sem ga sintetizirala iz raztopin bakrovega sulfata in kalijevega oksalata. Produkte sem analizirala s pomočjo rentgenske praškovne difrakcije (XRD), infrardeče spektroskopije (IR), termogravimetrične analize (TGA), diferenčne dinamične kalorimetrije (DSC) in z optičnim mikroskopom (OM). S pridobljenimi rezultati sem ugotovila, da se ne glede na temperaturo sušenja sestava produkta ne spremeni. Iz uklonskih vrhov na difraktogramih XRD, ki se pojavijo pri istih uklonskih kotih, sklepam na tvorbo enake kristalinične faze. Pri analizi FTIR se pojavijo značilna absorpcijska nihanja za sintetizirano spojino. Rezultati TGA in DSC do 400 °C potrdijo glavne komponente produktov, 2 molekuli vode ter oksalatne ione. Z rezultati termične analize produkta, sintetiziranega pri 90 °C, ugotovim, da se razlika pojavi zgolj pri načinu odcepa vode, kar lahko nakazuje na drugačno vezavo 2 molekul vode. Slike optičnega mikroskopa prikazujejo enake modre kristalčke, ki so se tvorili kot skupki oziroma posamezni kristalčki. Posamezne kristalčke sem lahko definirala kot oglata telesa, povprečno velikost kristalčkov pa sem ocenila na 100 µm.

• Language: Slovenian
• Keywords: kristaliničnost, infrardeča spektroskopija, diferenčna dinamična kalorimetrija, termična analiza, rentgenska praškovna analiza
• Work type: Bachelor thesis/paper
• Organization: FKKT - Faculty of Chemistry and Chemical Technology
• Year: 2024
• PID: 20.500.12556/RUL-164010
• Publication date in RUL: 15.10.2024

Secondary language

• Language: English
• Title: /

Abstract

In my diploma thesis, I investigated how the drying temperature (50 °C or 70 °C) affects the structure and composition of potassium bis(oxalato)cuprate(II) dihydrate synthesised from hot solutions of copper sulphate and potassium oxalate. The products were analysed by X-ray powder diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and optical microscopy (OM). The results obtained show that the composition of the product does not change regardless of the drying temperature. From the diffraction peaks in the XRD diffractograms, which appear at the same diffraction angles, I conclude that the same crystalline phase is formed. The FTIR analysis shows characteristic absorption peaks for the synthesised compound. The TGA and DSC results up to 400 °C confirm the main components of the products, 2 water molecules and oxalate ions. Based on the results of the thermal analysis of the product synthesised at 90 °C, I find that the difference is only in the thermal degradation of the water, which could indicate a different bonding of the 2 water molecules. The optical microscope images show identical blue crystals formed as clusters or single crystals. I was able to define the individual crystals as angular bodies and the average size of the crystals was estimated to be 100 µm.

• Keywords: crystallinity, infrared spectroscopy, differential dynamic calorimetry, thermal analysis, X-ray powder analysis