Education of the republic of uzbekistan tashkent state technical university named after islam karimov

Figure 1. Diagram of the change in the value 
of the free energy of the reaction 
CaCO
3
= CaO + CO
2
 
Figure 2. Diagram of the change in the 
value of the free energy of the reaction 
FeS
2
 = FeS + S 
Formed by reaction (2), carbon dioxide CO
2
interacts with elemental sulfur formed by 
replies (4) with the formation of carbon monoxide (CO). 
3S + 2CO
2
+2О
2
= 3SO
2
+ 2CO (4) 
The resulting carbon monoxide reduces ferrites and zinc silicates to iron and silicon 
oxides by the following reactions 
ZnО∙Fe
2
O
3
+ CO = ZnO + 2FeO + CO
2
(5) 
2ZnО∙SiO
2
+ 2CO + O
2
= 2ZnO + SiO
2 
+ 2CO
2
(6) 
The results of thermodynamic calculation of the change in the value of free energy for 
reactions (4), (5), and (6) are shown in Figures 3,4 and 5. 
Formed during the reaction (5) and (6), oxides of iron and silicon interact with calcium 
oxide formed during the response (2), with the formation of ferrites and calcium silicates. 

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Geological Engineering
133 
Figure 3. Diagram of the change in the value 
of the free energy of the reaction 
3S + 2CO
2
 + 2O
2 
= 3SO
2
 + 2CO 
Figure 4. Diagram of the change in the 
value of the free energy of the reaction 
Zn
О∙
Fe
2
O
3
 + CO = ZnO + 2FeO + CO
2
Figure 5. Diagram of the change in the value 
of the free energy of the reaction