What factors affect catalyst performance in catalytic reforming?

Reformer catalyst factors: Feedstock quality - sulfur poisons Pt (must be <0.5 ppm), nitrogen and metals also harmful, naphthenes content determines hydrogen and aromatics yield. Operating conditions - temperature (activity vs. selectivity), pressure (lower favors aromatics but increases coking), H2/HC ratio (suppresses coking). Catalyst type - Pt on acidic alumina, promoted with Re or Sn for stability, chloride for acidity. Deactivation mechanisms: coking (reversible by regeneration), metal sintering (irreversible at high temperature), poisoning (permanent). Regeneration: semi-regenerative (shutdown every 6-24 months), cyclic (swing reactors), CCR (continuous catalyst movement and regeneration). Catalyst life: 3-7 years for CCR, shorter for fixed bed. Performance monitoring: octane, hydrogen purity, and coke make.