Brunauer-Emmett-Teller surface areas

BET BMBF BOE Brunauer, Emmett, Teller (surface area) German Ministry of Education and Science Buffered oxide etching... 

In practice, the amount of solid molecules on the surface being exposed to the solution is difficult or even impossible to quantify. Instead, the solid surface area to solution volume ratio is often used to quantify the amount of solid reactant. Therefore, experimentally determined second-order rate constants for interfacial reactions have the unit m s h As the true surface area of the solid is very difficult to determine, the BET (Brunauer-Emmett-Teller) surface area is fte-quentiy used. The maximum diffusion-controlled rate constant for a particle suspension containing pm-sized particles is ca 10 m s and for mm-sized particle suspensions the corresponding value is I0 m s h Unfortunately, the discrepancy between the true surface area and the BET surface area and the non-spherical geometry of the solid particles makes it impossible to exactly determine the theoretical diffusion-controlled rate constant. 

ATR-FTIR attenuated total reflectance-I ouiicr transform infrared spectroscopy BET Brunauer-Emmett-Teller surface area measurement CA chronoamperometry... 

BET Brunauer-Emmett-Teller, surface area according to BET method... 

The BET (Brunauer-Emmett-Teller) surface area after calcination was found to amount to be 98 m /g. The surface area is therefore in the typical range of ternary industrial catalysts, which are between 60 and 100 m /g. 

The transport properties of electrospun nylon 6 mats have also been investigated by scientists. It has been found that the concentration of the polymer solution affected the fibre diameter, pore size, Brunauer-Emmett-Teller surface area and gas transport properties of the mats. It was shown that the filtration efficiency of nylon 6 nanofilters is superior to that of a commericial high efficiency particulate air filter for 0.3 micrometre test particles. Researchers found that the pore size and pore size distribution of electrospun polylacticacid (PLA) membranes are strongly associated with fibre mass, fibre diameter and fibre length. 

Acid Gas Removal. The aluminas that are used for acid gas removal obviously contain relatively high soda contents. Sodium is always contained in aluminas because Na(OH) is used in the Bayer process for extraction of alumina from bauxite. The typical content of Na20 in activated aluminas is 0.3% (wt). The soda content can vary considerably. The soda content in the alkalized alumina is typically >1%. The BET (Brunauer-Emmett-Teller) surface areas of activated aluminas are generally in the range 200-500 m /g, with total pore volumes near 0.5 cc/g. 

Quartz (particle size less than 0.5 mm, Brunauer-Emmett-Teller surface area 0.24 m g ) was prepared from sand collected at Fehervarcsurgo (Hungary). The sand sample (1 kg) was mixed with 1 mol 1 hydrochloric acid (21) and was left to stand overnight. The solid phase was separated and washed with deionized water until a sample of the aqueous phase gave no reaction with silver nitrate reagent. The quartz obtained was dried at 105 °C. 

Materials Technology Company. Ceram (online), http //www.ceram.com/test-ing-analysis/techniques/brunauer-emmett-teller-surface-area-analysis-bar-rett-joyner-halenda-pore-size-and-volume-analysis/ [accessed April 2,2012]. 

Brunauer-Emmett-Teller surface area BET measurements were conducted using a micrometries adsorption equipment (Quantachrome instrument, model Nova 2000, USA) determining nitrogen (99.99% purity) as the analysis gas and the catalyst samples were slowly heated to 300 for 3 hours under nitrogen atmospheric. Prior to analysis each precursors and catalyst and after reaction catalysts measurements specific surface area was evacuated at -196°C for 66 minutes. 

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