A novel permeation method to measure volumes

A new method to measure volume capacities of vessels has been developed and tested. The method uses a simple apparatus consisting of a calibrated membrane, pressure gauges, thermocouples and a chronometer. The apparatus is connected to a vessel of unknown volume: the vessel filled with a test gas is then pressurized (or depressurized). The knowledge of the mass transfer mechanism of the test gas through the membrane allows evaluating in an original way the volume of the vessel by means of pressure measurements vs. time. Potential applications concern the determination of the volume of vessels with irregular shapes both in laboratory (i.e., metrology, experimental chambers) and industry (i.e., fine and pharmaceutical chemistry). The main advantages with respect to the alternative gravimetric methods used for volume measurements are the avoided contamination with liquids, the reduced costs, the ease of use, and a good accuracy.