Incremental method for surface area and pore size determination
Abstract
Abstract AN APPARATUS FOR PRECISELY MEASURING THE SURFACE OF SOLIDS, PARTICULARLY THOSE IN PARTICULATE FORM. IN ESSENCE, THE MEASURING TECHNIQUE INVOLVES THE FLOWING OF TWO GASES WHICH ARE MIXED IN KNOWN PROPORTIONS AND ARE ALLOWED TO FLOW THROUGH A COOLED SAMPLE CELL CONTAINING A POWDER SAMPLE (ADSORBENT). ONE OF THE GASES (ADSORBATE) IS ADSORBED ON THE POWDER AND THE RESULTING CHANGE IN CONCENTRATION IS DETECTED. THE IMPROVEMENT IS CHARACTERIZED IN THAT THE RELATIVE PRESSURE OF THE ADSORBATE IS VARIED IN SLIGHT INCREMENTS WHEREBY THE ENTIRE ISOTHERM CAN BE OBTAINED, BUT THE VARIATION IS ACHIEVED BY VARYING THE FLOW RATES OF THE INDIVIDUAL GASES WHILE HOLDING THE TOTAL PRESSURE ALWAYS SUBSTANTIALLY AT ATMOSPHERIC.
Inventors
- 👤 Seymour Lowell
Bibliographic Details
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