Primary Products and Wall Effects on the Ethene Pyrolysis by a Quick Heating Method in the Presence of Heated Gaseous Diluent

Abstract

Prim4. ry products and reactions on the ethene pyrolysis in the range of 750 to 890°C under atmosAeric pressure in the presence of high temperature diluents (steam and nitrogen ) has been stUdied. The pyrolysis was carried out by a flow method in a spherical quartz reactor.The range of the residence time was 0.02∼0.65s, and the range of the partial pressure of ethene was 0.02∼0.8 atm.
The reaction product s obtained in the pyrolysis were hydrogen, 1, 3-butadiene, acetylene, propene, methane, ethane, butenes, polymer and/or tar, and carbon. Initial produc t formed was an equimolar mixture of hydrogen and 1, 3-butadiene. A major product at the lower partial pressure of: ethene was acetylene. The acetylene formation was not concerned with 1, 3-butadiene formation, and that recognized as ax effect of the reactor wall. Steam dilution was different in the rate of over-all reaction from nitrogen dilution. The rate in the steam dilution was first-order with respect to ethene, though changed to zero-order at the partial pressure lower than 0.1atm, While that in the nitrogen dilution was approaching to secondorder.