HNO3 MANUFACTURING WITH PROCESS FLOW DIAGRAM

HNO3 MANUFACTURING WITH PROCESS FLOW DIAGRAM

1. Production of N itric acid (HNO 3 )

2. From Chile saltpeter NaNO 3 and H 2 SO 4 react to produce NaHSO 4 and HNO 3 Electric oxidation of air N 2 and O 2 react (in the presence of electricity) to form NO and more O 2 Produces NO 2 and then this is mixed with water to produce HNO 3 Manufacturing methods

3. By catalytic oxidation of ammonia (Ostwald’s Process) Manufacturing methods….. Cont

4. Fuming Nitric Acid A red liquid made by bubbling NO 2 gas through concentrated HNO 3 Concentrated Nitric Acid It is of the density of 1.5, containing 98% HNO 3 Strong Nitric Acid It is of the density of 1.4, containing 65% HNO 3 Nitric acid types

5. Raw Materials Ammonia Water Air Catalyst (Platinum-rhodium gauze)

6. Oxidation of ammonia Oxidation of nitric oxide Absorption of NO 2 Steps involved in the production

7. Mixture of air & ammonia heated to 220˚C passed through a metal gauze made of platinum (90%) & Rhodium (10 %). 3X10 -4 sec Reaction produces a lot of heat energy. Energy is used to keep reaction vessel temp at 975-1225 K, typically 1200K Oxidation of ammonia

8. Side reaction: favored by high pressure and over heated catalyst Chemical Reactions involved

9. Colourless nitrogen monoxide gas produced from 1 st stage is then reacted with oxygen from the air to form brown nitrogen dioxide gas (NO2 ). Oxidation of nitric oxide

10. The nitrogen dioxide is then dissolved in water to produce nitric acid NO 2 +H 2 0 HNO 3 +HNO 2 HNO 2 + NO 2 HNO 3 + NO Thus overall reaction 2NO 2 +H 2 0 2HNO 3 + NO Absorption of NO 2

11. Prepare a flow chart to show the sequence of processes used to convert ammonia to concentrated nitric acid. Write equations for significant chemical reactions beside the appropriate section of the flow chart. Q-1

12. During the Ostwald process, nitrogen monoxide is made from ammonia at about 900°C and then cooled to 30°C before being reacted with air to make nitrogen dioxide . Both these reactions are exothermic. Why are the temperatures used for these reactions so different? Q-2

13. As the gas passes through the catalyst bed in the converter during nitric acid manufacture , its temperature increases. The gas must be cooled before it is mixed with air. Why does the temperature of the gas rise? Why is it necessary to cool the gas? What side benefit is obtained from the need to cool gases? Q-3

14. Describe two ways that expenses are minimized in the Ostwald process. Q-4

15. Gate Valve

16. Globe valve

17. Ball Valve

18. Butterfly valve

19. Check valve