Catalyst surface characterisations have been carried out to investigate the role of dispersion on catalyst activity and to probe the occurrence of oscillations in coking levels with cycle number generally observed during multiple deactivation and regeneration schemes. The titrations were done, cycle by cycle, at 430 degrees C after oxidation and at the same temperature (430 degrees C) after reduction at 500 degrees C. Results show the usually observed trend - that the dispersions after oxidation are higher than those after reduction. The average decline in dispersion from oxidation to reduction was calculated to be 39.25%. It was observed that the cycles with high toxic coke removal were characterised by high deactivation times. The deactivation times were still high even for cycles subsequent to those with low dispersion. At high dispersions the catalyst had short deactivation times, that is the small crystallites deactivate faster than large ones. The nature of reduceable coke and the efficiency of its removal is a much more determinant factor of catalyst activity than the level of metal dispersion. Thus prolonged toxic coke reduction at the high temperature of 500 degrees C, though resulting in an apparent lowering of dispersion, does not affect the quality of the catalyst. The dispersion before reduction could be reattained on oxidation. Hence reduction at 500 degrees C did not introduce sintering.