Modification of magnetic properties of siderite by thermal treatment

Download

index.pdf

Date

2007

Author

Alkaç, Dilek

Metadata

Show full item record

Item Usage Stats

209
views

142
downloads

Obtaining high magnetic susceptibility phases from HekimhanDeveci siderite orevia preliminary thermal treatment has been the basic target of the thesis study.Thermal decomposition characteristics of samples, determined bythermogravimetric analysis (TGA), differential thermal analysis (DTA), and differential scanning calorimetry (DSC), were referenced in advancement of thestudy. Heat treatment experiments, particularly roasting, were carried out byconventional heating and microwave heating. Results showed that roasting of HekimhanDeveci siderite samples could not be achieved by microwave energywhilst conventional heating experiments recorded success. Subsequentlowintensity magnetic separation of roasted samples gave recovery above 90%, where lowintensity magnetic separation of runofmine sample had failed. Formation of high magnetic susceptibility phases was verified by magneticsusceptibility balance and xray diffraction analysis (XRD), on roasted samples. Statistical modeling was applied to determine the optimum conditions of roastingin conventional heating system; based on heating temperature, time of heating, particle size as factors.It was concluded that roasting at T= 560 ºC, for t= 45 minutes was adequate toobtain desired results. Particle size was noted to be not much effective on the process as other factors at the studied size range. Kinetics (E, n) and reaction mechanism for the thermal decomposition in conventional heating system were evaluated with different solidstate reaction models by interpretation of the model graphs.Threedimensional diffusion reaction models reported to characterize the thermal decomposition well, with values of activation energy (E), E= 85.53 kJ/mol (Jander); E= 85.49 kJ/mol, (GinstlingBrounshtein).

Subject Keywords

Mining Engineering., Metallurgy.

URI

http://etd.lib.metu.edu.tr/upload/12608729/index.pdf
https://hdl.handle.net/11511/16749

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Hydrometallurgical processing of lateritic nickel ores Köse, Caner Hakkı; Topkaya, Yavuz Ali; Department of Metallurgical and Materials Engineering (2010) The objective of this thesis study is to recover nickel and cobalt at maximum efficiency from column leach liquor of lateritic nickel ores existing in Gördes region of Manisa by performing various hydrometallurgical methods under the optimum conditions. This column leach solution of nontronite type lateritic nickel ore was initially neutralized and purified from its basic impurities by a two stage iron removal process under the optimum conditions determined experimentally. Then, nickel and cobalt were preci...
Synthesis and characterization of bulk glass-forming iron-boron based alloy systems Gürbüz, Selen Nimet; Akdeniz, Mahmut Vedat; Department of Metallurgical and Materials Engineering (2004) The aim of this study, which was carried out in two main parts, is to investigate the glass forming ability of Fe-based systems. The first part involves the theoretical modeling to cover the requirement of a predictive model to identify the Fe-based alloy families that have high glass forming ability in the frame of atomistic and thermodynamic approach. The second part involves the experimental investigations to prove the results of the conducted theoretical modeling studies. For this purpose, in the first ...
Design and implementation of a current source converter based active power filter for medium voltage applications Terciyanlı, Alper; Ermiş, Muammer; Department of Electrical and Electronics Engineering (2010) This research work is devoted to the design, development and implementation of a Current Source Converter (CSC) based Active Power Filter (APF) for Medium Voltage (MV) applications. A new approach has been proposed to the design of the CSC based APF for reducing the converter kVA rating considerably. This design approach is called the Selective Harmonic Amplification Method (SHAM), and is based on the amplification of some selected harmoniccurrent components of the CSC by the input filter, and the CSC contr...
Synthesis of rare-earth doped lithium triborate Ardıçoğlu, Burcu; Özbayoğlu, Gülhan; Department of Mining Engineering (2005) Research in the field of non-linear optical (NLO) devices lead to an increasing interest in new borate compounds, capable of expanding the frequency range provided by common laser sources. Lithium triborate (LBO) is a newly developed ideal non-linear optical crystal used in laser weapon, welder, radar, tracker, surgery, communication, etc. Borates containing rare-earth elements are of great interest since they are found to be superior in non-linear optical applications. In this study, synthesis and identifi...
Optimization of conditions to produce manganese and iron carbides from Denizli-Tavas manganese ore by solid state reduction Akıl, Cem; Geveci, Ahmet; Department of Metallurgical and Materials Engineering (2007) Main purpose of this study was to find the optimum conditions to produce a charge material for ferromanganese production or steelmaking with high content of iron and manganese carbides from Denizli-Tavas manganese ore by carbothermic reduction and investigate the effects of temperature, time, amount of active carbon addition and CaO addition on this reduction. The ore was calcined and then mixed with active carbon and CaO. Experiments were performed in a horizontal tube furnace that can be heated up to 1700...

Citation Formats

D. Alkaç, “Modification of magnetic properties of siderite by thermal treatment,” M.S. - Master of Science, Middle East Technical University, 2007.