Patent ID: 8017090

Claim:
An apparatus for generating phosphine gas comprising: a reaction pot, an air compressor, and a dilution air blower; the reaction pot comprising an agitation air input, a dilution air input, a fumigant gas outlet, and a bottom; the bottom being conical in shape; the reaction pot being configured for producing 56 g to 10,000 g of phosphine gas at a concentration of 100 to 5000 ppm in less than two hours from a reaction mixture comprising predetermined amount of a granular metal phosphide in a predetermined amount of water; the dilution air input and the dilution air blower being configured to provide dilution air to the reaction pot in an amount effective to maintain concentration of phosphine gas in the reaction pot at less than 1.8% as phosphine gas is produced; the air compressor configured to provide agitation air to the reaction mixture at a turbulating pressure of 0.5 to 2.0 kg/cm 2 ; the dilution air input, the dilution air blower, the air compressor, and the agitation air input being configured to provide dilution air and agitation air in an amount effective to maintain the temperature of the reaction pot and phosphine gas at or below 55° C. as phosphine gas is produced; the fumigant gas outlet being configured for direct delivery of diluted phosphine gas from the reaction pot to the commodity.