Ethylene (C2H4) is oxidised with oxygen to produce ethylene oxide (C2HO) in a fluidised bed reactor...

  

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Ethylene (C2H4) is oxidised with oxygen to produce ethylene oxide (C2HO) in a fluidised bed reactor containing a silver catalyst. An excess of ethylene is used to keep the feed outside the flammability limit. The ethylene fresh feed contains 1.5 mole% of ethane (C2H6) with respect to the sum of the ethylene and ethane. The ethylene oxide is separated (assume 100%) and the unreacted ethylene plus ethane is recycled. Assume 100% of the oxygen is reacted. (a) Draw a process flow diagram and show all stream components. (b) Determine the limiting component. (c) For an ethylene oxide production of 2000 kg.h, a molar ratio of ethylene to oxygen at the reactor inlet equals to five and a purge of 10% of the separator outlet, calculate: (c.1) the rate of oxygen fed to the reactor. (c.2) the rate of ethylene in the separator outlet. the fresh feed and the purge streams. (c.3) All streams to be given in kmol.h to two decimal places. (d) In practice, a side reaction leads to CO2 and H-O. (d.1) Write the chemical equation of the side reaction. (d.2) Calculate the amounts of CO2 and H20 if 1% by mole of the oxygen undergoes the side reaction. What is the reduction in the ethylene oxide production? (d.3) Comment on the changes to the process if air (21% v/v Oz and 79% v/v (e) Na) is used instead of oxygen. Ethylene (C2H4) is oxidised with oxygen to produce ethylene oxide (C2HO) in a fluidised bed reactor containing a silver catalyst. An excess of ethylene is used to keep the feed outside the flammability limit. The ethylene fresh feed contains 1.5 mole% of ethane (C2H6) with respect to the sum of the ethylene and ethane. The ethylene oxide is separated (assume 100%) and the unreacted ethylene plus ethane is recycled. Assume 100% of the oxygen is reacted. (a) Draw a process flow diagram and show all stream components. (b) Determine the limiting component. (c) For an ethylene oxide production of 2000 kg.h, a molar ratio of ethylene to oxygen at the reactor inlet equals to five and a purge of 10% of the separator outlet, calculate: (c.1) the rate of oxygen fed to the reactor. (c.2) the rate of ethylene in the separator outlet. the fresh feed and the purge streams. (c.3) All streams to be given in kmol.h to two decimal places. (d) In practice, a side reaction leads to CO2 and H-O. (d.1) Write the chemical equation of the side reaction. (d.2) Calculate the amounts of CO2 and H20 if 1% by mole of the oxygen undergoes the side reaction. What is the reduction in the ethylene oxide production? (d.3) Comment on the changes to the process if air (21% v/v Oz and 79% v/v (e) Na) is used instead of oxygen.

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Recycle CR a H4 Fresh feed Cz HA Reacfor Sepirator GHA Prockect C ... View the full answer