The Kinetics of Ethylene Decomposition on Iron Catalyst

Abstract

The effect of ethylene partial pressure and temperature on the hydrocarbon decomposition rate was studied. As a catalyst, a triply promoted iron catalyst (with addition of small amounts of potassium, calcium and alumina oxides) was used. The mean crystallites size was ca. 17 nm. The processes were performed using pure ethylene or ethylene-nitrogen mixture under atmospheric pressure at the temperature range from 400 to 460 • C. The growth of carbon mass as a function of reaction time was measured using a thermobalance. The phase composition of the samples after ethylene decomposition was determined using X-ray diffraction technique. The reaction rate was independent of ethylene partial pressure in the range from 0.25 to 1 bar. The maximal carbon yield for given experimental conditions was estimated.

Response of cold briquetted iron (CBI) to high temperatures treatment

“…5) strongly suggests that the cementite in CBI completely dissociates into alpha iron and carbon at this temperature through equation (7). Fe 3 C = 3a-Fe + C DH = 5.77 KJ (7) This finding also supports an earlier report that cementite decomposes at a temperature of 738°C [22,23]. What actually happens at 930°C is not very certain.…”