BET Surface Area Analyzer


BET Surface Area Analyzer quantachrome, Autosorb iQ2, BET Surface Area & Pore Volume Analyzer is an instrument to determine the specific surface area of powders, solids and granules. Analyses: Single- and Multipoint BET (Brunauer, Emmett, and Teller) surface area, thickness, pore area distributions (BJH method), pore volume, and pore surface area Langmuir surface area, Temkin and Freundlich isotherm analyses.

Unique Features:

Physisorption
The Autosorb iQ2 can determine total BET surface area with remarkable sensitivity. Multi-point or single point measurements can be performed. Surface area of 0.01 m 2 /g and upwards can be accurately determined using nitrogen at liquid nitrogen temperature. The ASiQwin software automatically displays the BET plot and computes the BET ā€œCā€ constant, y-intercept, slope, and correlation coefficient of the least-squares best fit. In addition, the Micropore BET Assistant function enables the user with the click of a button to determine the correct linear BET range for a microporous material.
The shape of the typical isotherm provides various useful information on the large uptake of nitrogen at low P/Po indicating filling of the micropores. The linear portion of the curve represents multilayer adsorption of nitrogen on the surface, and the concave upward portion of the curve represents filling of meso-and macropores. An entire isotherm is needed for one to calculate the pore size distribution of the material

Chemisorption
Some surfaces, especially catalysts, are sufficiently reactive to form chemical bonds with certain gases. In contrast to physisorption, chemical adsorption (chemisorption) involves the formation of strong bonds between adsorbate molecules and specific surface locations known as active sites. Chemisorption is thus used primarily to evaluate quantitatively the number of surface active sites which are likely to promote (catalyze) chemical reactions. Both static adsorption isotherms and dynamic pulse titrations yield monolayer uptake, metal area, nanocluster (crystallite) size and active metal area of heterogeneous catalysts. Isothermal results can be used to map surface energetic heterogeneity via heat of adsorption calculations.

Available gas options: N 2 /CO 2 /H 2 ; Gas Mixtures: 5%H 2 & 95%N 2 , 5% Oxygen & 95% He and 20% Ammonia & 80% He


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