Catalyst Deactivation Field Audit Checklist

Catalyst deactivation is a critical performance-limiting phenomenon in heterogeneous catalytic processes—such as ammonia synthesis, hydrocracking, Fischer–Tropsch synthesis, and automotive exhaust treatment—where loss of activity, selectivity, or stability compromises safety, economics, and environmental compliance. Deactivation mechanisms fall broadly into three categories: sintering (thermal agglomeration of active metal particles), fouling (physical blockage by coke, dust, or salts), and poisoning (chemical adsorption of inhibitors like sulfur, arsenic, or chlorine on active sites). The Field Audit Checklist operationalizes this mechanistic understanding by guiding auditors through structured inspection protocols—including visual reactor internals assessment, thermocouple array analysis, pressure drop profiling, and feed/product assay correlation—to distinguish between reversible (e.g., coke burn-off candidates) and irreversible (e.g., permanent structural collapse) deactivation modes. Beyond diagnostics, the checklist supports predictive maintenance scheduling, catalyst replacement justification, and root cause analysis for regulatory reporting (e.g., EPA Process Safety Management or ISO 55001 asset management standards). Its design emphasizes traceability: each audit item links observed symptoms (e.g., rising ΔP across bed, declining conversion at fixed T/P) to probable mechanisms, enabling cross-functional alignment between operations, reliability engineering, and catalyst vendors.