In CaO-AI 203-and CaF2-CaO-AI,03-slags the soluted water vapour was quantitatively determined with Fourier-Transform-Infrared-(FT-IR-)spectroscopy. The slags were equilibrated at 1500 and 1600°C with definite H 20-and H 20/HF-partial pressures, respectively. The liquid slags were quenched in liquid 0 20. They solidified glassily. Water vapour exists in the slags soluted as OH--ion. For all slags investigated a linear dependence of the integral extinction upon the square root of the H 20-partial pressure, respectively upon HF-partial pressure, was determined. The values of the integral extinction (CaF 2-CaO-AI203-slags) are calibrated by a H 20-doping-technique. The solution enthalpy of H 20 in CaO-AI 203-slags was estimated: endothermal reactions. Interpretation of the vibrational range yielded in a mainly tetrahedral coordination of A13+ with 0 2-and F--ions in the glassy state. By heating the glassily solidified CaO-AI 203-slags were transformed into their crystalline products: shifting of IR-peaks. The CaO-AI 203-and CaF.-CaO-slags were compared with a CaO-Si0 2-AI203-slag.The FT-IR-method is quick. The water content can be estimated with an uncertainty of less than ± 5% and is, therefore, suitable for process control of metallurgical procedures. Wasserdampfloslichkeit in geschmolzenen ESU-Schlacken der SystemeCaO-AI.0 3 und CaF.-CaO-AI.0 3 unter Anwendung der Fourier-Transform-Infrarot-Spektroskopie. In CaD-AI 203-und CaF 2-CaO-AI203-Schlacken wurde geloster Wasserdampf mit der Fourier-Transform-Infrarot-(FT-IR-)Spektroskopie quantitativ bestimmt. Die Schlacken wurden bei 1500 und 1600°C mit definierten H 20-bzw. H 20/HF-PartialdrOcken ins Gleichgewicht gesetzt. Die f10ssigen Schlacken wurden in schwerem Wasser abgeschreckt. Sie erstarrten glasig. Der Wasserdampf lost sich in den Schlacken als OH--Ion auf. FOr aile untersuchten Schlacken wurde lineare Abhanqiqkeit zwischen integraler Extinktion und der Quadratwurzel des H 20-Partialdruckes bzw. HF-Partialdruckes bestimmt. Die integrale Extinktion (CaF 2-CaO-AI203-Schlacken) wurde durch eine H,o-Dotierungstechnik geeicht. Die Losunqsenthalple des Wassers in CaO-AI 203-Schlacken wurde bestimmt: endotherme Reaktionen. Die Auswertung des Schwingungsbereiches der Schlackenkomponenten ergab, daB AI'+ bevorzugt mit 0 2-bzw. F--Ionen tetraedrisch koordiniert ist. Umkristallisation der glasig erstarrten CaO-AI 203-Schlacken wurde durch Tempern erreicht: Verschiebung von IR-Peaks. Die CaO-AI,03-und CaF 2-CaO-AI203-Schlacken wurden mit einer CaO-Si0 2-AI203-Schlacke verglichen. Die FT-IR-Methode ist schnell. Der Wassergehalt kann mit einem Fehler unter ± 5 % bestimmt werden. Sie ist deshalb zur ProzeBkontrolle bei metallurgischen Ablauten geeignet.
The IR emission of liquid CaO‐Al2O3 slags is caused by IR active molecule vibrations of and ‐complexes. In the liquid CaO‐Al2O3 slags the equilibrium dominates. At lower temperatures (1000°C) the formation of condensed ‐complexes was observed (glassy state). By the addition of B2O3 to CaO‐Al2O3 slags B‐O‐Al associations were formed. Since the emission bands of the aluminate complexes overlap, a curve fitting with Gaussian functions was carried out to separate the bands. Furthermore, this quantitative evaluation leads to statements concerning the ratios between the different molecules. With the increase in temperature these associations are dissociated. In CaF2‐CaO‐Al2O3 slags with higher contents of CaF2, Al‐O‐F complexes with the coordination number 4 are present. Water vapour is dissoluted in liquid CaO‐Al2O3 as hydroxide‐ions (diffuse IR‐emission‐spectrum of −O‐H−…O2−‐molecule units).
The IR‐emission of CaO ‐ Al2O3‐melts (1873 K) is caused by IR‐active molecular vibrations of AlO 2−‐ and AlO 33‐‐complexes. In the CaO ‐ Al2O3‐melts the equilibrium AlO 2− + O2‐ ⟺ AlO 33‐ dominates. At lower temperatures (1000°C) the formation of condensed AlO 45‐‐complexes was observed (solid phases).
Structural information of liquid oxide melts including statements concerning their basicity are important not only for the metallurgy of steelmaking but also for the refractory industry, for ceramic productions and for glass manufacturing. After the introduction of infrared emission spectroscopy of liquid melts up to 1600°C it is now possible to receive UV/VIS‐spectra of these melts in different atmospheres. The comparison to already published spectra is possible by recording spectra of quenched samples at room temperature with the same optical system as the high temperature ones. The suitability of the Fe‐ and Cr‐Ions as test‐ions for the indications of the features of liquid aluminate melts is discussed. A new spectroscopical method for the investigation of melts above 1450°C was developed. Octahedral‐coordinated Fe3+ causes intensive charge‐transfer (CT) absorptions in the melts. These CT‐bands shift towards higher wavelengths and get broader and more intensive at higher temperatures; the results are discussed by the use of the Urbach‐approximation. The CT‐bands of Cr(VI) are attached to various chromate species. The properties of liquid silicates will be the subject of a later investigation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.