Patent number: 6845651

Quick BET method and apparatus for determining surface area and pore distribution of a sample

Original Assignee: Porous Materials, Inc.

Field of technology: Industrial Machinery and Processes

Patent granted on: Tue, 25 Jan 2005

Patent drawing

Abstract

A pressurizable sample chamber of known volume holds a sample with unknown porosity characteristics. The sample chamber has a known pressure (or vacuum). A flow controller preferably controls the flow of the pure gas to be adsorbed by the sample in the sample chamber. A pressure monitor preferably monitors the pressure in the sample chamber. Once the pressure approaches a target pressure, the flow controller is closed. The pressure monitor continues to monitor the pressure until it stops changing when an equilibrium is attained. The amount of gas introduced into the system through the flow controller and the volume and final pressure of the sample chamber are used to calculate the amount of gas adsorbed. This calculation is subsequently used to determine the porosity characteristics of the sample. Some of these characteristics include, but are not limited to, pore distribution and surface area.