## Degradation Phenomenon Catalyst bed degradation was observed during extended thruster operation. After 50+ seconds of continuous HTP flow, decomposition efficiency declined from 80% to below 60%. The catalyst bed was losing activity progressively during extended burns, while short test pulses performed normally. ## Root Cause Analysis Testing with ultra-pure HTP from specialty suppliers revealed the cause: stabilizer poisoning from commercial-grade HTP. Technical-grade HTP (49.5%) contains organic stabilizers designed to prevent decomposition during storage and transport. These stabilizers accumulated on the catalyst surface, progressively blocking active sites and destroying catalytic activity. Ultra-pure HTP without stabilizers showed virtually no degradation over extended burns, proving the problem was stabilizer contamination rather than catalyst material or thermal effects. ## Practical Implications The thruster could not operate reliably with technical-grade HTP containing stabilizers, regardless of catalyst material. Short pulses with minimal stabilizer accumulation performed well; extended burns showed unacceptable performance loss. Catalyst regeneration or frequent replacement were impractical for development. ## Solution Path The solution was clear: purify HTP in-house using vacuum distillation to remove stabilizers and raise concentration. This would eliminate stabilizer poisoning and provide clean, high-concentration propellant for reliable thruster operation. Investment in vacuum distillation capability was required.