1 / 8

INDUSTRIAL APPLICATIONS

INDUSTRIAL APPLICATIONS. Haber process And Contact process. Haber process. Manufacture of ammonia N 2 (g) +3H 2 (g)  2NH 3 (g), H= - 92kJmol -1 ( exothermic ) a.Uses of ammonia : manufacture fertilisers , dyes and explosives

hadleym
Télécharger la présentation

INDUSTRIAL APPLICATIONS

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. INDUSTRIAL APPLICATIONS Haber process And Contact process

  2. Haber process • Manufacture of ammonia • N2(g) +3H2(g)  2NH3(g), • H= -92kJmol-1 ( exothermic ) • a.Uses of ammonia : manufacture fertilisers , dyes and explosives • b.LCP suggest that high pressure and low temperature will shift equilibrium to the right and produce more ammonia

  3. c. However ,other economic factors (time and cost factors) must also be considered such as: • i) Low temperature not used – rate is slow • Note : high temperature also not used because • Equilibrium shifts left , lower yield • Therefore use a moderate temperature

  4. ii) pressure not too high • Reason : High pressure incurs higher cost of maintenance and also more expensive to build

  5. d. Optimum conditions : • 450 – 5500 C • 100 – 250 atm • Catalyst Fe • Note : • % yield of NH3 = less than 20 % • Pressure used reasonably high due to : • Forward reaction favored , more NH3 • Higher collision frequency , faster reaction

  6. Contact process • Manufacture of sulphuric acid • (1) S(g) + O2(g)  SO2(g) • (2) 2SO2(g) + O2(g)  2SO3(g) • H= -192kJ mol-1 ( exothermic ) • (3) SO3 (g) + H2SO4 (l) H2S2O7 (l) • oleum • H2S2O7 (l) + H2O (l)  2H2SO4 (aq)

  7. a. LCP suggest that high yield of SO3 (equilibrium shifts right) is favored by high pressure and low temperature • b. Optimum conditions : • 400 – 4500C • 1 – 2 atm ( % yield = 95 % hence high pressure not used ) • Catalyst (vanadium pentoxide ,V2O5 )

  8. High yield achieved under the following conditions: • (1) Air used to burn sulphur must be clean • Reason : Catalyst easily poisoned/damaged • (2) Catalyst needs to be cooled • Reason : Exothermic rxn hence catalyst gets hot • Or low temp favors forward reaction

More Related