porozymetri

Porozymetry is a technique used in analytical chemistry to determine the size distribution of pores in a material, such as a membrane or a porous solid. The method is based on the principle that molecules of different sizes will diffuse through a porous material at different rates. In porozymetry, a mixture of molecules of known sizes is allowed to pass through the porous material, and the time it takes for each molecule to pass through is measured. By comparing these times to a standard curve, the size distribution of the pores in the material can be determined.

The most common porozymetry technique is based on the use of gas molecules. In this method, a mixture of gases of different molecular weights is passed through the porous material, and the time it takes for each gas to pass through is measured using a mass spectrometer or a gas chromatograph. The size of the pores is then determined by comparing the retention times of the gases to a standard curve.

Porozymetry is a useful technique for characterizing the pore size distribution of materials, which is important in many fields, including catalysis, separation processes, and drug delivery. It is a non-destructive technique, meaning that the sample is not damaged during the analysis, and it can be used to characterize both open and closed pores. However, it is important to note that the accuracy of the results depends on the quality of the standard curve and the purity of the gas mixture used.