From Particle Formation...
... To Particle Characterisation


High Pressure Gas Sorption Analyzer

High pressure adsorption measurements are important in the fields of carbon dioxide sequestration, methane storage, hydrogen storage, and gas separation. The iSorb-HP instruments (volumetric sorption apparatus) generate automatic measurements of full adsorption and desorption isotherms over a wide range of pressures and temperatures.

The iSorb series is a family of four such high pressure sorption analyzers; one and two-sample models each available with an upper pressure limit of 100bar or 200bar, complete with built in vacuum pumps and sample degassing capability. All models feature pressure transducers both in the dosing manifold and on the sample cell for maximum sensitivity; this also provides the iSorb-HP2 model the capability to simultaneously analyze two samples.

Measurements are defined in terms of pressure or dose amount for both adsorption and desorption, equilibrium criteria, sample temperature (according to the heating /cooling device selected) and choice of equation of state (EoS):

  • Schmidt-Wenzel type, defined in terms of Helmholtz free energy (NIST recommended)
  • MBWR (Modified Benedict-Webb-Rubin type, Jacobsen 32-coefficients, NIST recommended)
  • Lee-Kesler (generalized Benedict-Webb-Rubin)
  • Peng-Robinson
  • Soave-Redlich-Kwong
  • Redlich-Kwong
  • Van der Waals
  • Ideal gas

Analysis temperatures are achieved either by recirculator bath (-20oC to 100oC, see below), cryocooler (<75K), or heating mantle (up to 400oC).

Carbon dioxide excess isotherm



EOS Adsorption Isotherms


Analysis stations 1 2
Gas inputs 2 (optional 4) 2 (optional 4)
Max pressure data 200 bara 200 bara
Min pressure data 0.0005 bar 0.0005 bar
LP transducers 2 (1 bar) 3 (1 bar)
HP transducers 2 3
Total transducer count 4 6
Transducer accuracy <±0.05% f.s. <±0.05% f.s.
Vacuum pump internal internal
Turbo pump option yes yes
Degas type automatic automatic
Degas ports in-situ in-situ
Heating Mantle (standard) yes yes
Max degas temp (°C) 400b 400b
Thermostatted bath (option) yes yes
Booster option yes yes
Thermostatted manifold yes yes
Gas inputs at side for easy access for easy access
PHYSICAL iSorb-HP1 iSorb-HP2
Height (cm) 110 110
Width (cm) 100 100
Depth (cm) 60 60
Weight (kg) 140 148
a or 100 bar for lower pressure model
b using heating mantle(s) provided.

Read more about BET surface area & gas adsorption.

For more information contact us.

iSorb HP High Pressure Gas Sorption Analyzer


Gas pressure booster increases cylinder pressure from 55bar to 200bar. This compensates for the drop in pressure from a standard laboratory cylinder as gas is used for analyses and ensures a constant supply of high pressure gas.

Isotherms can be measured from -20 to +100C with this recirculator. This liquid chiller/heater /circulator provides stable sample temperatures from -20oC up to 100oC set via PC. Includes jacketed cell.

For more information contact us.