Catalytic decomposition of ammonia in the gas feed to the turbine is a
potential method for reducing NO, emissions in coal gasification powe
r plants. Since the decomposition reaction is equilibrium limited at g
asification conditions, a membrane reactor is necessary to achieve a h
igh conversion of ammonia to nitrogen and hydrogen. The objective of t
his study was to experimentally demonstrate the use of a membrane reac
tor for ammonia decomposition at temperatures, pressures, and ammonia,
nitrogen, and hydrogen concentrations within the range of conditions
found at coal gasification plants. A composite palladium-ceramic membr
ane was used in the membrane reactor. Ammonia conversions from the pac
ked bed membrane reactor are compared to experimental conversions from
a conventional packed bed reactor operated under identical conditions
to show the advantage of using the membrane reactor. An ammonia conve
rsion of over 94% was achieved in the membrane reactor compared to a c
onversion of 53% in the conventional reactor at a temperature of 873 K
and pressure of 1618 kPa. The advantage of the membrane reactor is ev
en more pronounced at lower temperatures. The ammonia conversion at 82
3 K was 79% in the membrane reactor compared to a conversion of only 1
7% in the conventional reactor. Experimental results are also compared
to those predicted by a membrane reactor model. The experimental conv
ersions and conversions predicted by the model generally showed good a
greement. The percent difference between predicted and experimental co
nversions was generally less than 10%.