Lecture 8: Thermo chemistry applications in metal extraction
Problem 1 : Carbothermic reduction
Carbothermic reduction is commonly used to produce metals from oxides. Calculate the heat required (in Kcal/Kg of Zinc) to produce Zinc from reduction of with carbon.The reactants, and C, enter at 250oc , whereas Zinc vapor and gas leave at .use the following data:
Components
(Cal/g.mol)
Cp (Cal/g.mol. K)
ZnO(s)
-83800
11.71+(1.22 X 10-3 T) –(2.18 x 105 T -2)
C(s)
0
0.026+(9.307X10-3 T)- (0.354x105 T -2)
Zn(s)
0
5.35+(2.40x10 -3T)
CO(g)
-26420
6.79+(0.98x10-3T)-(0.11x105 T-2)
Zn(l)
----
7.50
Zn(g)
--------
5.00
Solution:
Reactants are at 298 K and products at 1300 K
(1)
Reactants are at 298K; hence sensible heat in reactants is zero
To calculate heat content in products, following scheme may be adopted
Sensible heat in CO at 1300K =
Heat of reaction at 298 K =
Performing calculations on sensible heat of products by using Cp value and putting these values in equation 1
with carbon.The reactants, 
gas leave at 
.use the following data:
(Cal/g.mol) 
