Ethylene Oxide Control Technology Development for Hospital Sterilizers

摘要

The report discusses the development of ethylene oxide (EO) control technology for hospital sterilizers. Hospitals sterilize heat-sensitive items in gas sterilizers that use a mixture of EO (12 wt %) and a chlorofluorocarbon (CFC) (88 wt %). The active sterilizing agent is EO. The CFC is added as a flameproofing diluent. Two potential sterilizer emission control systems were tested: catalytic oxidation and acid hydrolysis. In catalytic oxidation, relatively dilute mixtures of air and EO (12/88) are passed through a catalyst bed at 149-177 C. In acid hydrolysis, EO is hydrolyzed to ethylene glycol using H2SO4 (the CFC is unaffected). A full-scale system was tested under laboratory conditions, simulating a system that could be used for hospital sterilizers. The tests showed that the EO destruction efficiency was 99.9-99.999% of the EO reaching the device. However, 45-60% of the EO was absorbed by the ethylene glycol used in the closed-circuit liquid-ring vacuum pump. Each system has significant advantages and limitations.