We use a pyrophoric catalyst in a polymerization reactor. The ZrCl₂ catalyst reacts violently with air and water. According to the catalyst manufacturer, the reactor, monomer feed tank and other tanks must be purged to 10 ppm-volume (ppmv) oxygen and 10 ppm-mass water. Monomer comes by railcar; the data sheet says the monomer meets a 10-ppmv oxygen standard; there's no measurable water present. The monomer goes through a molecular sieve dryer then it is fed to the reactor feed tank. After hydrotesting, air-drying and a nitrogen purge, we still can't get the feed tank oxygen down below 100 ppmv. However, we still can't get the monomer oxygen down to 100 ppmv in the feed tank. After 30 additional hours of purging, we can't get below 200 ppmv. The water in the tank is about 50 ppm. What can we do? What could be the source of additional oxygen and water?

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