Mettulurgy Flashcards
what is used in hall haroult process as an electrolyte and why?
Al2O3 + Na3AlF6(Cryolite) is used
because cryolite has low melting point
Mg has which method for extraction
Fused Salt Electrolysis
iron is removed from Chalcopyrite as
partial roasting of chalcopyrite produces
FeSiO3
Feo+Cu2O
Copper Pyrite formula and what is its common name
CuFeS2
Also Known as chalcopyrite
Pb from cheif ore has _______ reduction
Self Reduction
Sn(Tin) From Chief ore is done by ______reduction
Carbon reduction
cassiterite formula and what impurities does is contains
SnO2
impurities= Fe,Cu
Boron is extracted by Decomposition of its ____
Iodide
Why are nitrate ores not found!?
Nitrate ores are not found because all nitrate are water soluble.
Why do d-block generally form sulphide ore?
Heavy d-block metals generally form sulphide ore because polarising power of heavy d-block metals is high and polarisability of sulphide is high.
Limestone
CaCO3
haematite
Fe2O3
bauxite
Al2O3.2H2O
magnetite
Fe3O4
cassiterite
SnO2
siderite
FeCO3
calamine
ZnCO3
dolomite
CaCO3.MgCO3
Epsom
MgSO4.7H2O
azurite
2CuCO3.Cu(OH)2
malachite
CuCO3.Cu(OH)2
gypsum
CaSO4.2H2O
zinc blend/sphalarite
ZnS
cinnabar
HgS
horn silver
AgCl
cryolite
Na3AlF6
copper pyrite
CuFeS2
fluorspar
CaF2
carnallite
KCl.MgCl2.6H2O
iron pyrite
FeS2
galena
PbS
pyrolusite
MnO2
What happens in hydrometallurgy and what elements are reduced by this method?!
It involves reduction of metal in aqueous medium by more electropositive metal.
Ag, Au, Pt and also low grade ore of Cu are reduced by this method
Whats pyromettulurgy and the metals here are?
If heating effect is involved in extraction of metal from its oxide in presence of suitable reducing agent then it is named as pyrometallurgy.
Zn, Cr, Fe, Mn, Sn, Pb, Cu, Hg are the metals
Generally which elements are extracted via electrometullurgy
Highly reactives-s block metal and Aluminium
Whats the principle of gravity separation/levigation
This method is based on the difference in densities of the ore gangue particles.
Lighter impurity washed off with water and heavier ore particles settle down at the bottom.
Which ore has a magnetic impurity and what is the impurity called
Sn(Tin Stone) has a magnetic impurity and its called ⟶ wolfmarite (FeWO4 + MnWO4)
What are froth floatations primarily for?
It is employed for sulphide ores.
What’s the principal behind froth floatation
It is based on the differential wetting characteristics of the ore and gangue particles with water and oil and adsorption.
Ore particles are wetted by oil while gangue particles are wetted by water.
Eg of frothing agents
Reagents used as frothing agents (pine oil)
eg of collectors?
collectors used are (sodium ethyl xanthate and potassium ethyl xanthate)
eg of activators
Activators used are copper sulphate
eg of depressants and why are they used!?
When a sulphide ore contains impurity of other metal
sulphide to separate the depressant is used.
eg: PbS contains impurity of ZnS. To depress ZnS. NaCN is used.
Who invented froth floatation method?
a washer woman
ellingham diagram is a graph between!?
delta G and T
zone refining method is used for what type of stuff
its used for purifying the semiconductor metals
eg of metals which are purified by zone refining mtehod
Si (Silicon) Ge (Germanium) B (Boron) Ga (Gallium) In (Indium)
whats baeyers process
what happens to the aluminate obtained in the baeyer’s process
write the mac Arthur Forrest cyanide process reaction
and what’s the process type?
its a leaching process
generally whats used as a reducing agent in pyrometallurgy
carbon
how is ZnS treated in pyrometallurgy ( with no Oxygen involvement)
and why is it not so favorable!?
ZnS is treated with C to form Zn and CS2
but C-S bond isnt so strong and hence the reaction is not spotaneous
how is ZnS treated with the presence of O2?
ZnS is treated with O2 to form ZnO and SO2
then ZnO is treated with C to form Zn and CO2
CO2 is highly stable hence the reaction is spontaneous
what happens in calcination
- Ore is heated in the absence of air to remove water or CO2 from hydrated oxides or carbonates respectively.
- Process temperature is below the melting points of treated ores.
- During calcination moisture, volatile impurities are removed thereby ore becomes porous.
what are the reactions of calcination?!
what happens in roasting?
what happens in partial raosting?
give an eg of partial roasting?
whats copper matte
what does CuFeS2 contain?
whats flux and slag, explain with an eg
whats the trick of ellingham diagram
explanation of Ellingham diagram?
I. Ellingham diagram normally consists of plots of ΔGo vs T for the
formation of oxides of elements
II. The graphs for metal oxide have slope upwards because the change in
Gibbs’s energy becomes less negative with an increase in temperature.
III.Each plot follows a straight line unless there is some change in phase.
IV. When the temperature is increased, a point will be reached when
the line crosses ΔG = 0 line. Below this temperature the ΔGo of oxide
is negative and hence the oxide is stable. Above this temperature
ΔGo of the oxide is positive and hence the oxide becomes unstable
and decomposes on its own into metal and oxygen.
What’s introduced in the blast furnace?
Fe2O3 ore + limestone + coke is introduced into the blast furnace
what happens in combustion zone?
what happens reduction zone?
what happpens in slag formation zzone?
What’s blister copper?
Impure copper obtained in self-reduction has blister appearances and is therefore called Blister copper.
whats goldschmidt thermite process?
what is the principle of distillation and what are the metals employed in this??
This is based on the difference in boiling points of metals and impurities.
Impurities have a HIGH BOILING POINT than pure metal.
Employed for low boiling point metals like Zn, Cd, Hg, etc.
what is the principle of liquation and what are the metals employed in this??
This is based on the principle of difference in melting points of metal and impurity.
Employed for purification of low melting point metals like Pb, Bi, Sn, etc.
what is the principle of zone refining and what are the metals employed in this??
This method is based on the principle that the impurities are more soluble
in the melt than in the state of the metal. This process depends on the phase
rule and fractional crystallization.
This method is very useful for producing semiconductors and other
metals of very high purity.
Example - Germanium, Silicon, Boron, Gallium, and Indium.
what happens in vapor phase refining?!
In this method, the metal is converted into a volatile unstable compound (e.g. iodide), and impurities are not affected during compound formation.
The compound thus obtained is decomposed to get the pure metal.
what is the van Arkel process and what are metals employed in this?
Employed for purification of metals like Titanium, Zirconium, Hf
and Boron.
What’s Monds Process and what is the metal for which its used?
nickel is the metal
what are the types of iron and what are they composed of?
how are wrought iron and steel formed?