Improvements in or relating to the manufacture of ammonia

摘要

1,148,513. Synthesis of ammonia. CHIMKOMBINAT. 2 Nov., 1966, No. 49227/66. Heading C1A. [Also in Division B1] Ammonia is synthesized by reacting nitrogen and hydrogen in a reaction zone in the presence of a particulate catalyst wherein the catalyst is magnetic and in a fluidized state and wherein the catalyst is under the effect of an applied magnetic field, preferably created by an electromagnet, of which the field strength is such that the particulate catalyst is not carried out of the reaction zone by the flow of gas maintaining the catalyst in a fluidized state. Preferably the reaction is carried out above atmospheric pressure, with a volume hourly space velocity of the nitrogen-hydrogen mixture of over 10,000h-1, using a catalyst whose particle diameter does not exceed 4 mm. The reaction temperature may be from 50‹ to 125‹ C. lower than the optimum temperature for a stationary layer catalyst. The reaction may be carried out in the apparatus shown in Fig. 1 wherein the gas-synthesis mixture enters the upper part of the apparatus, passes down between the cylinder 1 and heat exchanger 2 and enters the lower part of the heat exchanger 8. The heated gas then passes upwardly through the heater 6, downwardly through the tubes 3, thus entering the lower portion of the catalyst zone wherein reaction takes place. The flow of gas mixture and the applied magnetic field fluidize the catalyst but the catalyst is contained with the reaction zone by the applied magnetic field generated by the magnets 4.