pórusméreteloszlás

Pórusméreteloszlás (porous size distribution) is the statistical distribution of pore sizes within a porous material. It characterizes the variety and frequency of voids ranging from nanometers to micrometers and is critical for understanding transport, adsorption, and mechanical properties.

The distribution is usually expressed as a pore volume or surface area function versus pore diameter, often plotted as a histogram or cumulative curve. Common descriptors include average pore size, modal diameter, and pore‑size range. The shape of the distribution can indicate homogeneity: a narrow peak suggests uniform pores, while a broad or multimodal curve reveals a heterogeneous structure.

Measurement techniques vary with scale. Mercury intrusion porosimetry forces mercury into pores under pressure, producing a volume‑pressure curve that is converted to a pore size distribution by the Washburn equation. For mesoporous materials, nitrogen adsorption–desorption (BET, BJH, or DFT analysis) is used; the desorption isotherm provides pore sizes between 2 and 50 nm. Small‑angle X‑ray scattering (SAXS) and electron microscopy (TEM, SEM) complement these methods by offering direct imaging or scattering-based size information.

In catalysis, porosimetry helps correlate active surface area with reaction rates. In geosciences, pore‑size distributions inform permeability and fluid retention in soils and rocks. Zeolites, activated carbons, and aerogels are typical examples where precise control of pórusméreteloszlás dictates performance.

Analytical software translates raw sensor data into pore‑size curves, often providing confidence intervals. Standardization bodies such as ASTM, ISO, and IUPAC provide guidelines to ensure reproducibility and comparability across laboratories.

Understanding pórusméreteloszlás enables engineers and scientists to design materials for filtration, energy storage, drug delivery, and petroleum recovery, making pore‑size analysis a cornerstone of porous media research and application.