Description

Porous and powder materials are widely applied in various branches of industry—ceramics manufacture, wastes recuperation, catalysis, metallurgy, aerospace technologies, power engineering, medicine and many other areas. Creation, distribution and application nanoporous medias demands presence of reliable and simple diagnostics and control methods for porous structure parameters. Now abroad a number of devices is small-scale produced. But as a whole these measurements are not routine. So demand in high informative methods porous for unspecialized laboratories remains actual.

The device is designed for pores size distributions and other parameters of nanoporous structure investigation. Operational principle is based on the original method developed in the Scientific Association of High Temperatures of the Russian Academy of Sciences (SAHT RAS). Technique is used desorption isotherms data calculation. Data is received without measurement of pressure of adsorbats vapors. The method uses the kinetics of the sample drying in quasi-equilibrium conditions analysis, i.e. time dependence of a working liquid weight loss from sample. The developed software allows to obtain the exact data about the nanopores sizes on the basis of existing theoretical representations about sorption phenomena for the various materials.

The device includes standard analytical balance, the air thermostat and special measuring cells for the specimens (fig. 1, 2). The device can be used by unspecialized laboratories and for the materials express-control in the industry.

Fig. 1

Fig. 2

The main specific features of the device:

• non-destroying control technique;
• the only measured parameter is time dependence adsorbat weight loss from sample;
• wide choice of adsorbates;
• application possibility for samples of almost any chemical nature, the form (including thin membranes), dispersion and other samples with pores volume from 5 mkl;
• operation conditions: temperature close to room and atmospheric pressure;
• routine measurements are spent continuously without need in operator presence;
• device can be used by any unspecialized laboratory.

Now specimens with pores sizes in the range of 1–100 nanometer can be analyzed on existing experimental setup. Expansion of pores range to 0.5–1000 nanometers is the main aim of the profile research group activity in SAHT RAS. Thus it is necessary to underline that carrying out of measurements by the most widespread method low-temperature nitrogen adsorptions with pores radius less than 5 nanometers, and also more 50 nanometers represents now a serious scientific and technical problem. The existing device is widely applied to the analysis of ceramic-metal and polymeric membranes, catalysts, adsorbents and carriers, carbon-blacks, aluminum oxide and hydroxide (fig. 3), carbon-polymeric of the composites, the supersewed polymers, ion-exchanging membranes and many other porous medias.

Fig. 3

Developer

Joint Institute for High Temperatures of Russian Academy of Sciences (JIHT RAS)