What are heterogenous catalysis? Give examples.

When the catalyst exists in a different phase than that of reactants, it is said to be heterogeneous catalyst, and the catalysis is called heterogeneous catalysis. For example, SO2 can be oxidized to SO3 using vanadium pentaoxide (V2O5or platinum (Pt) as catalyst.

1023_heterogeneous catalysis.png 

Here, V2O5 is solid, while the reaction reactants are gaseous. This reaction is employed during the manufacture of sulphuric acid by Contact Process.

In heterogeneous catalysis, the catalyst is generally solid while the reactants are gases and the reaction starts from the surface of the solid catalyst. That, is why heterogeneous catalysis is also is also called surface catalysis.

Some more examples of industrially important heterogeneous catalytic reactions are:
Manufacture of NH3 from N2 and H2 by Haber's process, using iron as catalyst.

794_heterogeneous catalysis1.png 
Manufacture of CH3OH from CO and H2 using (a mixture of Copper, ZnO and Cr2O3) as catalyst.

1590_heterogeneous catalysis2.png 
Oxidation of NH3 with O2 using Pt as catalyst in Ostwald process.

73_heterogeneous catalysis3.png 
Oxidation of polluting gases such as CO and NO into non-toxic gases by the catalytic converter in the car's exhaust system. The catalytic converter consists of a mixture of transition metals such as platinum, palladium and rhodium. These catalysts oxidize CO and unburnt hydrocarbons to CO2 and H2O and reduce oxides of nitrogen to N2.

618_heterogeneous catalysis4.png 
Hydrogenation of oils to form vegetable ghee using finely divided nickel as catalyst.

954_heterogeneous catalysis5.png

Polymerization of ethylene using TiCl3 and trialkyl aluminium (Ziegler-Natta method) as catalyst.

   Related Questions in Chemistry

  • Q : Number of mlecules in methane Can

    Can someone please help me in getting through this problem. The total number of molecules in 16 gm of methane will be: (i) 3.1 x 1023 (ii) 6.02 x 1023 (iii) 16/6.02 x 1023 (iv) 16/3.0 x 1023

  • Q : Preparation of ammonium sulphate Select

    Select the right answer of the question. Essential quantity of ammonium sulphate taken for preparation of 1 molar solution in 2 litres is: (a)132gm (b)264gm (c) 198gm (d) 212gm

  • Q : Real vapour pressure Choose the right

    Choose the right answer from following. The pressure under which liquid and vapour can coexist at equilibrium is called the : (a) Limiting vapour pressure (b) Real vapour pressure (c) Normal vapour pressure (d) Saturated vapour pressure

  • Q : Modern periodic table and Mendeleevs

    Differentiate between the modern periodic table and Mendeleevs table?

  • Q : Which is largest planet in our solar

    which is largest planet in our solar system

  • Q : Problem based on molarity Choose the

    Choose the right answer from following. The molarity of a solution of Na2CO3 having 10.6g/500ml of solution is : (a) 0.2M (b)2M (c)20M (d) 0.02M

  • Q : Extensive property Choose the right

    Choose the right answer from following. Which one of the following is an extensive property: (a) Molar volume (b) Molarity (c) Number of moles (d) Mole fraction

  • Q : Explain the molecular mass with respect

    During the formation of polymers, different macromolecules have different degree of polymerisation i.e. they have varied chain lengths. Thus, the molecular masses of the individual macromolecules in a particular sample of the polymer are different. Hence, an average value of the molecular mass is

  • Q : What are different mechanisms for

    Nucleophilic substitution reactions in halides containing  - X bond may take place through either of the two different mechanisms,S<

  • Q : Question based on strength of solution

    Help me to go through this problem. On dissolving 1 mole of each of the following acids in 1 litre water, the acid which does not give a solution of strength 1N is: (a) HCl (b) Perchloric acid (c) HNO3 (d) Phosphoric acid

©TutorsGlobe All rights reserved 2022-2023.