Investigation of the Para-Orthro Shift of Hydrogen

Abstract

An investigation of means of promoting the low temperature para-orthohydrogen reaction was conducted. The principal means studied was the synthesis of active heterogeneous catalysts; this approach succeeded in producing a catalyst that was 29 times more active, on a weight basis, than the standard ferric oxide gel material. Studies were conducted to establish a logical engineering model describing the observed kinetic behaviour of this catalyst. It was found that by adjusting the kinetic data to account for temperature gradients within the catalytic reactor and concentration gradients within the catalyst particles that the data closely fit a first order-reversible rate law based on gas phase composition. Means of packaging this catalyst into an efficient catalytic reactor were also studied. As a result of the high catalyst activity, a reactor concept allowing both high flow area, and low bed thickness in the flow direction is required. To satisfy this need a reactor was built in which the catalyst was supported in the form of a thin cylindrical shell, with hydrogen entering the inside of the cylinder and flowing radially through the catalyst shell. The pressure drop obtained with the two units tested was of the order of 10% of that obtained when the catalyst is packaged in an axial flow packed bed reactor of typical length to diameter ratio. The activity of the catalyst in this unit compared with the activity achieved in the typical axial flow unit is of the order of 70%; it is expected that optimization of the design parameters would increase this factor significantly. A study was made of the effect of hydrogen ion-hydrogen molecule collisions on the para-orthohydrogen reaction rate. The results indicate that this is not a suitable means for promoting the reaction.

Document Details

Document Type
Technical Report
Publication Date
Sep 01, 1966
Accession Number
AD0805143

Entities

People

  • A. H. Singleton
  • A. Lapin
  • J. F. Kucirka

Tags

DTIC Thesaurus Topics

  • Air Force
  • Air Force Facilities
  • Axial Flow
  • Catalytic Reactors
  • Contracts
  • Engineering
  • Flow Rate
  • Geometry
  • Heat Transfer
  • High Pressure
  • Ionizing Radiation
  • Low Temperature
  • Mass Transfer
  • Mathematical Models
  • Measurement
  • Physical Properties
  • Radial Flow
  • Standards
  • Temperature Gradients
  • Thermal Conductivity

Readers

  • Molecular Photonics/Laser Physics
  • Plasma Physics / Magnetohydrodynamics
  • Rocket Propulsion.