Beitrag zur Kenntnis des Ablaufs der endothermen Umsetzung von Benzinkohlenwasserstoffen mit Wasserdampf im Röhrenreaktor

Abstract

In the steamreforming of naphta in externally heated tubes, gases with different compositions of carbon dioxide, carbonmonoxide, hydrogen, and methane are formed, depending on the naphta feed.

The following can be determined by measuring probes in a test reactor:

• The primary reformed products of naphta and steam are carbon dioxide and hydrogen due to the initial high steam surplus, referred to the gas formed at the onset.
• If naphta conversion velocity is known, semi empirical kinetic equilibrium curves for components H₂O, CO₂, CO, H₂, CH₄ can be calculated.
  Practical measurements of concentrations follow the tendency of these curves with larger or smaller deviations. With the catalyst on hand and the selected temperature gradient an accelerated steam conversion combined with increased hydrogen and carbon monoxide-carbon dioxide production can be observed at the beginning.
• Over the whole range of the reactor the equilibrium temperature for the Boudouard reaction equivalent to quotient P_CO/P_CO2 remains behind the effective temperature i. e. the formation of carbonblack is not possible.
• Under the described conditions the reaction heat requirement is always positive. Peaks in the heat requirement occur at the inlet and outlet of the reactor.