Chemisorption Series
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ChemiSorb™ Series Chemisorption Analyzers The Science and Technology of Small Particles™

Economical Chemisorption Analyses ChemiSorb Series Chemisorption Analyzers The Versatility of the Chemisorption Technique for Catalyst Characterization Knowledge of surface chemistry and surface structure is essential in the design, production, and application of a catalytic material. The Micromeritics ChemiSorb 2720 and 2750 quickly and accurately measure the quantity of adsorbed or desorbed molecules allowing determination of these characteristics. The ChemiSorb 2720 makes chemisorption and physisorption analyses affordable for applications in which owning an instrument had once been...

Catalytic cracking – Catalytic processes are used extensively for refining petroleum. Acid catalysts such as zeolites are used for catalytic cracking and are often characterized using ammonia chemisorption and temperature-programmed desorption for determining the number and strength of the acid sites. Typical ChemiSorb Applications Catalysts – The active surface area and pore structure of catalysts have great influence on reaction rates and yield of product. Limiting the pore size allows only molecules of desired sizes to enter and leave; creating a selective catalyst that will produce...

The Analytical Technique The ChemiSorb 2720 and 2750 both utilize the dynamic (flowing gas) technique of analysis. The quantity of gas adsorbed from the gas stream by the sample is monitored by a downstream thermal conductivity detector (TCD). The temperature and pressure at which adsorption/desorption occurs is either known or monitored. The instruments can be used to study physical or chemical adsorption. Preparation usually is accomplished by flowing either an inert or chemically active gas over the sample. After preparation, another gas is selected for analysis. Prep and carrier gases...

ChemiSorb Features Four Carrier Gas Inlets Push Button Selection of Carrier and Preparation Gases Flow Path Options Analysis Ports 1 Preparation Port 1 Injection Septum Y Injection Loop Sample Reactor Quartz Gas Inlets Carrier 4 Preparation 1 Loop Temperature Control Integrated 2‡ Max Temperature 400 °C With TPx option 1100 °C Fan-assisted Cooling 1 Standard Analyses Pulse Chemisorption Y Physisorption Y ChemiSoft TPx Analyses TPR Y TPD Y TPO Y Pulse Chemisorption Y Physisorption Y Loop Calibration ChemiSoft TPx Reports % Metal Dispersion Y Metal Surface Area Y Average Crystallite Size Y...

Temperature-Programmed Chemisorption Option When the optional programmable furnace system and accompanying ChemiSoft TPx another category of chemical adsorption programmed reactions reduction (TPR), Temperature control is provided by a furnace that operates from ambient (20 °C) to 1100 °C, and is able to produce tempera- ture ramps of up to 50 °C/min within the 20 to 500 °C range, 30 °C/min within the 500 to to 1100 °C range. The furnace controller can be programmed to provide multiple ramps and soak times. Temperature-programmed chemisorption provides information about adsorption strength...

Data are reduced and reported automatically by the ChemiSoft TPx software, which is part of the Temperature-Programmed Chemisorption option and can be used with either ChemiSorb instrument. Reports include single- and multipoint BET surface area, percent dispersion, peak area volume, calculated stoichiometry factor, gram molecular weight, crosssectional area, calculated metal density, active (metallic) surface area, active particle (crystallite) size, and activation energy (first order kinetics). Data Reduction and Reporting Versatility When used with the ChemiSorb 2750, additional reports...

The Science and Technology of Small Particles Micromeritics Instrument Corporation Micromeritics China - Beijing Office Shi-Hao Ming-Di (Ten-Mansion) Rue Antoine Laurent Lavoisier Micromeritics GmbH Avantis Science Park Unit 2, Chestnut House 178-182 High Street North Micromeritics N.V./S.A. 20068 Peschiera Borromeo, Milano 5F Tokatsu Techno Plaza