ACTIVITY AND THERMORESISTANCE OF FUSED IRON CATALYSTS FOR AMMONIA-SYNTHESIS

The activity and thermoresistance of five industrial catalysts were examined. Kinetic measurements were carried out in an isothermal, flow differential reactor under 10.0 MPa in the 400-520°C temperature range. In thermoresistance tests, overheating of the catalysts was carried out at 650°C for 24 h, or at 620°C for 24 to 192 h. The relationships obtained during both experimental tests were similar, with 24-h operating at 650°C giving a similar activity decrease as ageing for 192 h at 620°C. The chemical composition of the catalysts (XRF) was determined. © 1990.