- Type of paper
: Paper in journal
Title: Obtaining of the Active form of Magnesium Oxide from
Serpentinite
- Authors:
- Ćosić, Milomir (74254)
- Žuljević-Šipalo, Josip (47030)
- Milković, Marina (71506)
Journal: Kemija u industriji
Number: 4
ISSN: 0022-9830
Volume: 40
Year: 1991
Pages: from 133 to 138
Number of references: 12
Language: hrvatski
Summary: The active MgO form is prepared from serpentinite. By
thermal treatment in the fluidized bed reactor, the main constituent
mineral: serpentine-antigorite, decomposes to give simple oxides. Applying
CO2 pressure leaching of thermally treated serpentinite suspension, MgO is
converted into soluble Mg(HCO3)2. Different magnesium carbonate forms are
precipitated by aeration and heating of such a Mg(HCO3)2 solution. By
heating up to 40 C, the crystalline MgCO3*3H2O is precipitated, and above
this temperature the voluminous basic carbonate 4MgCO3*Mg(OH)2*4H2O.
Thermal decompositon of both mentioned carbonates gives the high purity MgO
active form (MgO fraction over 99%).
Keywords: Serpentinite, Obtaining, Magnesium Oxide, Active Form, Leaching
- Type of paper
: Paper in journal
Title: Chemical Procedures in Obtaining Magnesium Oxide
- Authors:
- Ćosić, Milomir (74254)
Journal: Kemija u industriji
Number: 8
ISSN: 0022-9830
Volume: 40
Year: 1991
Pages: from 305 to 308
Number of references: 35
Language: hrvatski
Summary: The review presents a literature survey of chemical
procedures used for MgO extraction from low grade magnesites, dolomites,
sea-water, waste magnesium salts and from magnesium silicate -serpentinite.
The application of the given procedures makes it possible to produce a high
purity MgO, having properties that depend on the procedure in question.
Keywords: Magnesium Oxide, Chemical Procedures, Obtaining
- Type of paper
: Paper in journal
Title: Corrosion Products Analysis of Aluminosilicate Bricks from
the Blast Furnace Air Preheater
- Authors:
- Navala, Dragica (33212)
- Ćosić, Milomir (74254)
- Ribarić, Dagmara
Journal: Metalurgija
Number: 3
ISSN: 0543-5846
Volume: 30
Year: 1991
Pages: from 109 to 115
Number of references: 9
Language: hrvatski
Summary: Corrosion products of aluminosilicate bricks have been
investigated after nine years use in the blast furnace air preheater in the
Metallurgical Works " Željezara Sisak". Corrosion reaction of heat and dust
contained in the blast furnace gas resulted in forming reaction products of
three layers on the brick surface of different thickness. It was concluded
that the obtained corrosion layers had different chemical-, phase- and
morphological composition. Chemical compounds, as result of brick corrosion
in the high temperature zone of the blast furnace air preheater, affect
termomechanical properties of the brick what may cause checkworkers
deformation and the disturbance of the complete air preheater operation.
Keywords: Bricks, Aluminosilicate, Corrosion
- Type of paper
: Paper in journal
Title: Obtaining of Iron, Cobalt and Nickel Concentrates from
Serpentinite by Leaching with Hydrochloric Acid
- Authors:
- Ćosić, Milomir (74254)
- Milković, Marina (71506)
- Dmitrović, Radana (57786)
Journal: Kemija u industriji
Number: 9
ISSN: 0022-9830
Volume: 41
Year: 1992
Pages: from 361 to 367
Number of references: 15
Language: hrvatski
Summary: By leaching of serpentinite with HCl; Mg, Fe, Ni and Co
formed a solution together with other soluble elements present in
serpentinite as admixtures. Amorphous SiO2 and insoluble admixtures were
separated by filtration, whereas Mg, Fe, Al, Ni, Ca, Cr, Mn, Co, Zn, Cu, V
and Ti remained as chlorides in the solution having pH of about 0.5. The
results of increasing the solution pH is the precipitation of insoluble
hydroxides and oxyhydroxides. Selective precipitation took place due to the
difference in solubility products of the hydroxides - the cations
precipitated in respective pH value range. In this way, the high-grade
concentrates of iron, cobalt and nickel were obtained.
Keywords: Concentrates, Iron, Cobalt, Nickel, Leaching, From Serpentinite
- Type of paper
: Paper in journal
Title: Obtaining Nickel Powder from Oxide Ores by the Ammoniacal
Leaching Process and Reduction by Hydrogen
- Authors:
- Milković, Marina (71506)
- Žuljević-Šipalo, Josip (47030)
- Ćosić, Milomir (74254)
Journal: Kemija u industriji
Number: 11
ISSN: 0022-9830
Volume: 42
Year: 1993
Pages: from 391 to 398
Number of references: 54
Language: hrvatski
Summary: A literature rivew of the development and teoretical basis
of ammoniacal leaching process for obtaining of nickel from oxide ores are
presented. It is one of hydrometallurgical processes which had appared as
potential possibility at the beginin of this century, and later it was
industrially applicated, e.g. Carons process.
The possibility adequate application of ammoniacal leaching process for
treating of nickel and cobalt concentrates, obtained from serpentinite by
leaching with HCl, is emphasized.
The reduction of nickel from leach solution by hydrogen is also presented
in this paper.
Keywords: Oxide Nickel Ores, Ammoniacal Leaching, Reduction by Hydrogen, Nickel Powder.
- Type of paper
: Paper in journal
Title: Application of Mossbauer's Spectroscopy to Metallurgy
- Authors:
- Ivanušić, Vera (63094)
Journal: Metalurgija
Number: 3
ISSN: 0543-5846
Volume: 32
Year: 1993
Pages: from 101 to 104
Number of references: 18
Language: hrvatski
Summary: This paper gives a survey of some possibilities for
application of Mossbauer's spectroscopy to metallurgy. It considers
metallurgical systems as well as those systems which are more and more
important for the manufacture of new materials.
Keywords: Mossbauer Spectroscopy, Application, Metallurgy.
- Type of paper
: Paper in journal
Title: Influence of Chemical and Petrographical Characteristics
of Coking Coal on the Coke Quality
- Authors:
- Legin-Kolar, Mira
- Rađenović, Ankica
- Barać, Gordana (79320)
Journal: Metalurgija
Number: 4
ISSN: 0543-5846
Volume: 32
Year: 1993
Pages: from 141 to 144
Number of references: 14
Language: hrvatski
Summary: The chemical and petrographical characteristics of the
coking coal blend (65% Russian and 35% Australian) were examined. The
petrographical characteristics are basic parameters for the predictioning
of the coking coal capability. Moisture, volatile matter and ash contents,
qualitative composition, types of metals and nonmetals compounds in the
coal blend and coke produced from the same blend were investigated.
Keywords: Coking Coal Blend, Coke, Chemical Analysis, Petrographical Analysis, Sulphur, Trace Elements in Coal and Coke
- Type of paper
: Paper in journal
Title: Hydrated magnesium carbonates, their transformations and
thermal decomposition to give magnesium oxide
- Authors:
- Ćosić, Milomir (74254)
- Burevski, Dončo
- Milković, Marina (71506)
Journal: Kemija u industriji
Number: 2
ISSN: 0022-9830
Volume: 43
Year: 1994
Pages: from 41 to 48
Number of references: 17
Language: hrvatski
Summary: In the article the various species of the hydrated
magnesium carbonates, as well as their transformations and thermal
decomposition, were considered. The various species of magnesium
carbonates, obtained by the magnesium leaching with CO2 from the aqueous
suspension of the thermaly treated sepentinite, were analysed. Depending on
reaction conditions the following compounds are prepared: MgCO3*3H2O,
MgCO3*Mg(OH)2*2H2O, MgCO3*Mg(OH)2*H2O and 4MgCO3*Mg(OH)2*4H2O. From this
compounds only MgCO3*3H2O and 4MgCO3*Mg(OH)2*4H2O were investigated in more
detail, it was measured their: apparent density, specific surface area and
the size and morphology of the powder particles. Differential thermal
analysis (DTA) and thermogravimetric analysis (TGA) were adopted to trace
their thermal decomposition. The dependence of the particular specific
surface area on the heating temperature for the 4MgCO3*Mg(OH)2*4H2O
samples, was also found. The one hour long calcination of the MgCO3*3H2O
and 4MgCO3*Mg(OH)2*4H2O specimens at 700 C yields the well dispersed and
active MgO solids; their apparent density, specific surface area and powder
particle morphology is also included in this article.
Keywords: Hydrated Magnesium Carbonates, Thermal Decomposition, Magnesium Oxide
- Type of paper
: Paper in journal
Title: Composition and Component Structure in the Nickel and
Cobalt Concentrate Prepared by Leaching Serpentinite
- Authors:
- Ćosić, Milomir (74254)
- Milković, Marina (71506)
- Žuljević-Šipalo, Josip (47030)
Journal: Kemija u industriji
Number: 6
ISSN: 0022-9830
Volume: 43
Year: 1994
Pages: from 277 to 282
Number of references: 28
Language: hrvatski
Summary: In the article the concentrate of Ni and Co obtained from
serpentinite by leaching with HCl was studied. The portion of the
contributing metals and the forms of thier occuring compounds in the
concentrate were measured and investigated. Ni and Co contents in the
concentrate are 16.03% and 0.70%, respectively. Along with Ni and Co, the
concentrate also containes Al and Mn as well as small amount of the other
elements. The concentrate is coprecipitate of hydroxides and oxyhydroxides
of metals, which cations existing as admixtures in the serpentinite. During
Ni and Co precipitation on and in the gel, made of the already precipitated
admixed components, the part of Ni and Co is subject to the surface
oxidation with oxigen from the air forming crystallinic compounds:
4Ni(OH)2-NiOOH and 4Co(OH)2-CoOOH, the contents of which, in the
concentrate, are 25.26% and 1.10%, respectively.
Keywords: Serpentinite Admixtures, Coprecipitation of Hydroxides, Nickel and Cobalt Concentrate, Composition, Component Structures
- Type of paper
: Summary in proceedings
Title: Solvent Extraction of Cobalt (II) and Nickel (II) with
Ester of Phosphonic Acid (MOOP)
- Authors:
- Lenhard, Zdenka
- Maljković, Darko
- Hršak, Damir (900667)
Proceedings title: Sinopsisi/Abstracts
Language: hrvatski
Place: Zagreb
Year: 1995
Pages: from 295 to 295
Meeting: XIV. skup hrvatskih kemičara i IV. hrvatski simpozij o kemiji i tehnologiji makromolekula
Held: from 02/06/95 to 02/08/95
Summary: As a part of the studies of extraction of metals from the
leaching products obtained by means of acidic leaching away of laterite
minerals and discarded hard metals, conducted for the purpose of enhancing
the separation procedures, we investigated the extraction of Co and Ni with
organophosphoric extractant under the name of MOOP produced by Bayer.
The researchar were conducted on synthetic samples with aquaeous -
organic phase ratio A/O 1 and 2. The choice of other experimental
conditions in this phase of the investigation provided us with the
opportunity of comparison of the effectiveness of MOOP with the already
investigated organophosphoric reagent of phosphine type Cyanex 272 produced
by Cyanamid.
We investigated the influences of the original pH - pHi, on the
extraction of Co and Ni, separated and in the mixture. We calculated the
distribution ratios, Dc, and the separation factors, A. The highest ratios
were Dc Ni=3,6 (pHi=8, V/O=2) and Dc Co=29,3 (pHi=8, V/O=1), while the best
separation factors were found to be A Co/Ni=53,3 (pHi=6, V/O=2).
Under certain experimental conditions we observed the emergence of the
third liquified phase, as well as the mutual influence of the metals. In
the end, the extraction powers of MOOP and Cyanex 272 were compared.
Keywords: Cobalt (II), Nickel (II), Extraction, Separation.
Other: Nije naznačen urednik zbornika radova, stoga taj podatak
nedostaje.
- Type of paper
: Prototype
Title:
- Type of paper
: Ph.D.
Title: The Preparation of Mulitte in Al2O3-SiO2
Faculty: Fakultet kemijskog inženjerstva i tehnologije Zagreb
Date of defense: 12/23/91
Language: hrvatski
Number of pages: 122
Summary: Mullite, 3Al2O3*2SiO2, was synthesized by reaction
sintering a mixture of kaolinite and Al2O3. The influence of mineralizers
(NaF, TiO2, MnO and Cr2O3), has been investigated. Among the examined
mineralizers, TiO2 shows efficient influence on the mullitization process.
Efficiency of TiO2 dependence upon its quantity and the reaction
temperature. The microstructure and microanalyses of the samples were
defined by using SEM and AEM analyses. Two morphologically and
compositionally different mullites have been found out (the large prismatic
mullites and the small needle-shaped ones, embedded into the glassy matrix)
but also rutile in the form of needle-shaped crystals embedded in the
glassy matrix.
Keywords: Mineralizers, Mullite, Reaction Sintering
- Type of paper
: M.A.
Title: The Effect of the Petrographical and Granulometrical
Composition of the Coking Coal Blends to the Prognosed Quality of Coke
Faculty: Fakultet kemijskog inženjerstva i tehnologije Zagreb
Author: BARAĆ GORDANA
Date of defense: 05/24/91
Language: hrvatski
Number of pages: 128
Summary: Researches in this work included coking coal blends
investigations with a view to predict coke quality on the coking coal
quality base and by using petrographical methods. The samples investigated
were coking coal blends from the east market (the former USSR) and from the
west market (the USA and Canada). The investigations have been carried out
on the average samples and on the samples classified to the classes
according to the grain sizes (<0.5mm, 0.5-3.15mm, >3.15mm). The same
methodology research has been used on the all samples, which included
chemical, rheological and petrographical testings. In the development of
the researching methodology, special contribution represent the defining
and a way of petrographical indexes receiving on the base of which coke
quality has been predicted. The results obtained represent a contribution
to the development of the researching methodology which refers to the
defining of the petrographical contents and petrographical indexes as
basical parameters for the predictioning of the coking coal blends
capability.
Keywords: Coking Coal Blens, Petrographical Analyses, Granulometrical Composition, Quality of Coke
