ABOUT

• History and activity
• Structure
• Scientific employees
• Employees who worked
• Projects
• International projects
• Developments
• Gender Equality Plan
• Academic сouncil
• Specialized academic council
• Council of young scientists
• Ukrainian Mineralogical Society
• Committee on meteorites
• Postgraduate studies, doctoral studies
• Center for collective use
• Mineralogical Museum named after Academician V.I. Vernadsky
• Contacts

PERIODICALS

• Геохімія та рудоутворення
• Мінералогічний журнал
• Записки Українського мінералогічного товариства

INFORMATIONAL
MESSAGES

• Exhibition
• Defense of dissertation
• Conference
• Scientific readings
• Director elections
• Vacancies
• Solemn meeting of the Academic Council
• Popularization in mass media
• Lecture, seminar

Regulations of transformation of the structure and magnetic characteristics of iron oxides and oxyhydroxides as a basis for solution of mineralogical, material science and technological problems

ABSTRACT

 

Report on the SRW: 1 book, 48 pages, 46 illustrations, 5 tables, 15 references.

 

Purpose of the work: The purpose of the project is the experimental study and theoretical analysis of patterns and mechanisms of transformation of the crystal structure and magnetic properties of iron oxides and oxyhydroxides under the influence of external factors.

Research methods and equipment: magnetometry method (magnetometer with a Hall sensor), magnetic resonance method (EPR spectrometers RE-1306 (Russia), PS100X (Belarus)), X-ray diffraction method (DRON-4M), NGR spectroscopy, scanning electron microscopy , thermomagnetic studies.

Results and their novelty: Collections of samples of oxides and hydroxides from deposits of the Kryvorizky mining district and the Urals were created. The phase composition, magnetic characteristics, and chemical composition of samples from the created collections were studied. The influence of temperature, acid-alkaline and redox conditions, and magnetic fields on the processes of transformation of the crystal structure and properties of goethite and hematite into magnetite and maghemite was studied. Relatively simple and cost-effective new approaches to the transformation of weakly magnetic minerals (goethite, hematite) into strongly magnetic minerals (maghemite, magnetite) have been developed. Procedures for the transformation of goethite and hematite into magnetite under the influence of temperature in the presence of reducing agents were carried out. The X-ray diffraction method shows that after special treatment, hematite and goethite phases disappear and a new magnetite phase appears. It is shown that the saturation magnetization after special treatment increases by 10-50 times compared to the original sample. The novelty of the developed technique is that the magnetization procedure does not require high temperatures.

Recommendations for the use of the results of the work: the obtained results can be used to solve the problems of processing oxidized iron ores, as well as to solve the environmental problems associated with the disposal of dumps and tailings in Kryvyi Rih.

Authors:

Ponomarenko Oleksandr Mykolaiovych

Other authors:

Bryk O.B., Yushyn O.O., Dudchenko N.O.

Keywords:

crystal structure, magnetic properties, phase transformations, iron oxides and hydroxides, magnetite, maghemite, hematite, goethite

Head of the research:

Ponomarenko Oleksandr Mykolaiovych

Registration Card (RC):

0112U003586

Execution period of the research:

2012 - 2013