The GeoPyc® 1360 measures the envelope density (sometimes called bulk density) of rigid and semirigid, porous materials. Unlike absolute density, which excludes the volume of pores and small crevices, envelope density is the mass of an object divided by its volume including the pore volume. When the sample’s absolute density (sometimes called skeletal, true, or real density) is supplied, the GeoPyc automatically calculates the sample’s percentage total porosity and specific pore volume. (Absolute density can be obtained using Micromeritics’ AccuPycTM 1330.)
The GeoPyc uses a dry-fluid medium — called DryFlo® — to measure the sample’s volumetric displacement. Because DryFlo conforms to sample surfaces without entering pores, irregularly-shaped samples and even samples comprised of multiple objects can be analyzed.
Unlike other methods, such as mercury intrusion and hot-wax dipping, the GeoPyc 1360 method is generally non-destructive of the sample, rapid, easy to perform and involves no handling or disposal of hazardous materials.
The GeoPyc completes density analysis and automatically prints a report in 5 to 20 minutes, depending on user-selected parameters. This rapid sample turnaround makes the GeoPyc an ideal quality control tool for many industries. Reducing analysis time and/or analyzing a larger percentage of samples means that production can respond more effectively to quality standards, whether the goal is to maximize the porosity of catalyst substrate or to minimize the porosity of powdered metal objects.
The GeoPyc could be most useful, however, when a constant level of product porosity must be maintained within narrow specifications. The GeoPyc’s method facilitates quick identification and correction of changes in product porosity. The simple technique and fully-automated process are designed to minimize human error.
The GeoPyc is also convenient for most labs because it is quiet and compact, and requires only an electrical supply (no gases or liquids).
A variety of materials ranging from highly porous to nonporous can be analyzed. A sampling of materials with typical results is shown in Table 1.
The tests giving these results were performed on prototype instruments to demonstrate the GeoPyc’s capability. The tabulated information is believed to fairly represent the great range of applicability and utility of the GeoPyc 1360.
GeoPyc, AccuPyc, and DryFlo are trademarks of Micromeritics Instrument Corporation.
