Gas supply vessel
A gas supply vessel for storing and dispensing a reagent gas including a filter such that the vessel is capable of delivering the reagent gas, after it is filtered, at a high level of purity. The filter includes a porous sintered body and is effective to provide a desired level of purity of a supplied reagent gas by flowing the reagent gas through the filter during delivery from the vessel at a low pressure, at a relatively low flow rate, and with a relatively low pressure drop across the filter.
1. A gas supply vessel for storing and dispensing a reagent gas, the vessel comprising:
vessel walls defining an interior volume having an interior pressure that is sub-atmospheric;
adsorbent within the interior volume defined by the vessel walls;
reagent gas contained within the interior volume, the reagent gas comprising a portion that is adsorbed on the adsorbent, and a portion that is present as gaseous reagent gas in equilibrium with the adsorbed reagent gas;
at least one valve in communication with the interior volume having an valve inlet and a valve outlet;
an outlet in communication with the interior volume; and
a filter secured to the valve inlet, the filter comprising a porous sintered body, the porous sintered body having a porosity ranging from 55 to 70 percent and a thickness in a direction of fluid flow of less than 3 millimeters, wherein the filter has a log reduction value of at least 4 at a particular MPPS, at a flow rate of 20 standard cubic centimeters per minute, and provides a pressure differential of less than 100 torr.
2. The vessel of claim 1 , wherein the filter has a log reduction value of at least 7 at a particular MPPS at a flow rate of 10 standard cubic centimeters per minute.
3. The vessel of claim 1 wherein the porous sintered body has a thickness in a range from 0.8 to 1.2 millimeters.
4. The vessel of claim 1 wherein the porous sintered body has a surface area (BET) in a range from 0.15 to 0.30 meters per square gram.
5. The vessel of claim 1 wherein the adsorbent is selected from a metal organic framework, porous organic polymer, and activated carbon.
6. A method of supplying a reagent gas from a vessel as recited by claim 1 , the method comprising delivering the reagent gas from the vessel.