CPMCM / Characterization of Porous materials/ Catalysts/Membranes
The nano and micro scale structural and surface properties of porous materials, catalysts and membranes determine their macroscopic performance in various industrial applications and can be studied by several static and dynamic techniques.
Macro (> 50 nm) and meso (2-50 nm) porosity is usually studied by high pressure Hg-porosimetry, while low pressure gas adsorption at cryogenic temperatures is used for characterizing meso and micro (<2 nm) pores. With such techniques information on surface area, pore shape and connectivity, pore size distribution, surface roughness, etc can be deduced. Moreover, datasets of both techniques can be combined with percolation-type approaches and inverse modeling algorithms to estimate unique values for all aforementioned pore structure parameters over the entire range of pore-length scales.
Low pressure adsorption equipment can be upgraded to work at high temperatures (e.g. ambient to 1000 oC) in “chemisorption” mode. With such instruments chemical phenomena (e.g. oxidation, reduction, bonding) taking place at the gas-solid interface can be monitored and thus the catalytic properties of active phases can be assessed.
Likewise, the interactions of materials with different molecules can be studied by means of thermal desorption spectroscopy (or temperature programmed desorption) systems coupled with mass spectrometry (TDS/MS, TPD/MS). In such systems a temperature ramp is applied to the sample and the temporal concentration changes of the desorbed gas(es) are continuously being analyzed.
High pressure manometric or gravimetric adsorption equipment can be used to measure amounts adsorbed, but also adsorption kinetics under realistic conditions. They provide thus a direct evaluation of sorbents’ and catalysts’ performance in real life applications such as gas separations, gas storage and catalytic processes.
Finally, isobaric counter current diffusion of single gases or mixtures (Wilcke-Kallenbach) is the most comprehensive technique for the characterisation of membranes (porous or dense, ceramic or polymeric), membrane contactors and reservoir rocks as diffusivity, activation energy, permeability and selectivity can be measured.
Thermal Desorption Spectroscopy/Mass Spectroscopy apparatus
3 x Mass Flow Controllers (1 x 100 ml/min, 2 x 10 or 30 ml/min)
1 x Back Pressure Regulator (0-20 bar)
Different Quartz Reactors (ID 40mm is the largest)
Pressures: 1-20 bar
Temperatures: Ambient to 800oC
Samples can be outgassed under vacuum (< 10-6 mbar) or inert gas flow
Samples can be pre-equilibrated with different gases
Temperature programmed desorption of different species
Desorption activation energies by applying different heating ramp rates
Hydrogen trapping in metals
TPR/TPO
The apparatus can be easily used for (e.g. packed bed) breakthrough experiments
Different Quartz Reactors (ID 40mm is the largest)Special cells for packed beds (200 mg to 200 g)
Dr. Theodore Steriotis (t.steriotis@inn.demokritos.gr)
+30 210 650 3614/3636
Micropore physi-/chemisorption analyzer: Autosorb iQ-C-MP (Anton PaaR GmbH)
Gases: N2, CO2, Kr, H2
P/P0: < 1x10-8 – 0.999
Pore size range: 0.35-500nm
Pressure Transducers: 1/10/1000 torr
Sensitivity: (1) < 2x10-8 moles adsorbed/desorbed gas (1 torr transducer), (2) < 2x10-7 moles adsorbed/desorbed gas (10 torr transducer), (3) < 2x10-5 moles adsorbed/desorbed gas (1000 torr transducer)
Degass ports: 4
Vacuum: 5x10-10mbar
Surface area (0.01 to >3000m2/g)
Pore size distribution
Chemisorption Furnace : 1373K for chemisorption analysis
Thermal Conductivity Detector (TCD) for TPD/TPR/TPO analysis
Homemade flow system for dynamic experiments of interaction of gaseous molecules with porous (catalytic) surfaces
Variable temperature reactors
Mass flow controllers
Two Mass Spectrometers (OmniStar, Pfeiffer Vacuum)
Dr. Theofilos Ioannides
theo@iceht.forth.gr
+302610965264
Mercury pore size analyzer: PoreMaster 60 (Anton Paar GmbH)
Two (2) low pressure stations with pressure range 1.4-345kPa
One (1) high pressure station with pressure range 0.14-414Mpa
Pore size range for low pressure station: 1100-4μm
Pore size range for high pressure station: 10-0.0036μm
Volume accuracy: ±1%fso or better
Volume resolution: ± 1x10-4cm3
Transducer accuracy: ±0.11% fso or better
Surface area (0.01 to >3000m2/g)
Pore size distribution
Homemade flow system for dynamic experiments of interaction of gaseous molecules with porous (catalytic) surfaces
Variable temperature reactors
Mass flow controllers
Two Mass Spectrometers (OmniStar, Pfeiffer Vacuum)
Dr. Tsakiroglou Christos
ctsakir@iceht.forth.gr
+30261965212
Micropore physi-sorption analyzer: Autosorb-1, MP (Quantachrome Instruments)
Gases: Ar, N2, Kr, CO2, CH4, H2, any permanent gas, vapors
P/P0: <3x10-10 – 0.995 (nitrogen)
Pressure transducer 1000 torr: Accuracy: ±0.11% full scale, Minimum resolvable pressure: 2.5 x10-4 torr
Pressure transducer 1 torr: Accuracy: ±0.15 % reading, Minimum resolvable pressure: 2.5 x 10-7 torr
Degas ports: 2 (2 heating mantles with max temperature 350oC)
Ultimate vacuum: 5x10-9mbar
Vapor Sorption option with heated manifold and vapor generator
CryoCooler: Cryogen free, temperature range: 20.00 – 320.00K
Home-made liquid bath, temperature range: 273 – 323K
Surface area: 0.01 m2/g to no known upper limit
Pore volume: Detectable volume limit: <0.0001 cc/g.
Pore size distribution range: 3.5 to >4000 Ångströms
Isosteric heat of adsorption
Argon filled glove box (MBraun) and cell seals for handling and transferring air sensitive samples
Dr. Theodore Steriotis (t.steriotis@inn.demokritos.gr)
+30 210 650 3614/3636
Any gas physi-/chemisorption analyzer: Autosorb IQ3-C-AG (Quantachrome/Anton PaaR GmbH
Gases: N2, O2, Ar, CO2, CO, H2, NH3, any permanent gas
P/P0: < 1x10-3 – 0.999
Pore size range: 0.35-500nm
Pressure Transducers: 1000 torr
Sensitivity: <5x10-5 moles adsorbed/desorbed gas (1000 torr transducer)
Sample stations: 3
Degass ports: 4
Chemisorption: yes
Chemisorption Furnace: up to 1373K for chemisorption analysis
Thermal Conductivity Detector (TCD) for TPD/TPR/TPO analysis
Dr. Fotios Katsaros (f.katsaros@inn.demokiritos.gr)
+30 210 650 3671
High Pressure Gas sorption analyzer: HyEnergy, PctPro-2000 (Setaram)
Static, manometric measurement type
Gases : H2, CO2, CH4, Ethylene, Propane, any permanent gas
Pressure range: 0.001 - 200bar
Temperature range: 77 – 673K
Pressure transducers: (1) 1x vacuum to 200 bar / Accuracy: 1% of the reading, (2) 1x vacuum to 5 bar / Accuracy: 1% of the reading
In situ outgassing (<10-6 mbar)
Dosing range: 0.3 micro-mole to 10 moles of gas
Gas storage, Gas separations, Study of gas solid interactions
MicroDoser: Option for very small samples down to milligrams (up to 25 bar)
Argon filled glove box (MBraun) for handling and transferring air sensitive samples
Dr. Theodore Steriotis (t.steriotis@inn.demokritos.gr)
+30 210 650 3614/3636
High Pressure Gravimetric instrument: Rubotherm
Magnetic Suspension Balance (MSB)
Static, gravimetric measurement type
Custom-made sample cell and gas handling
Gases : H2, CO2, CH4, Ethylene, Propane, any permanent gas
Pressure range: 0.01 - 200bar
Temperature range: 253 – 773K
Pressure transducer accuracy: 0.5% of the reading
Balance resolution: 1μg
Balance stability: ± 3μg
In situ outgassing (<10
Gas storage, Gas separations, Study of gas solid interactions
Circulating bath (253-323K), Sample Furnace (300-773K)
Dr. Theodore Steriotis (t.steriotis@inn.demokritos.gr)
+30 210 650 3614/3636
Intelligent Gravimetric Sorption analyzer: IG1-100A (Two stream IGA-100, Hiden Isochema)
Precision microbalance with a dual suspension arm
Static/Dynamic, gravimetric measurement type
Gases : H2, CO2, CH4, N2, Ethylene, Propane, any permanent gas, vapors
Pressure range: 0.05mbar - 20bar
Temperature range: -196oC – 1000oC, (CryoFurnace, water bath, FastFurnace)
Balance resolution: 0.1 μg
Balance stability: ±1 μg long term (± 0.1 μg short term)
Pressure transducers: 100 mbar/1bar/20bar, Accuracy: 0.05% full scale
In situ outgassing (<10-6 mbar)
Excess/Total uptake
Working capacity
Isosteric heat of adsorption
Diffusion constant (D)/Diffusion time constant (D/r2) calculation
Built-in anti-condensation protection to 50 °C for pure vapor sorption
De-mountable DryLoader for loading air sensitive samples. The system can hold a rough vacuum to remove the majority of air prior to filling with inert gas to improve purity of the resulting atmosphere
Argon filled glove box (MBraun) for handling and transferring air sensitive samples
Dr. Theodore Steriotis (t.steriotis@inn.demokritos.gr)
+30 210 650 3614/3636
Homemade, all stainless steel, gas permeability/selectivity apparatus
Operation modes: (1) Isobaric counter current diffusion, (2) Cross flow permeability/selectivity, (3) Dead-end permeability (pressure drop under constant flow), (4) Relative permeability (gas, vapor/pre-adsorbed vapor), (5) Membrane contactor and membrane reactor.
Gases: Single phase and binary/tertiary mixtures of all permanent gases and vapors.
Sweep gases: Usually He, Ar, N2
Pressures: 1-60 bar
Differential pressures: 0-10 bar
Temperature: From ambient to 300oC
Diffusivities: 10-5 to 10-11 cm2/sec
Permeance: 10-8 to 10-14 mol/m2/sec/Pa
Membrane conformation: Flat discs, films, tubular and multi-channel monoliths, hollow fibers
Membrane surface area: Depends on the permeation characteristics. Usual range from 2 to 500 cm2
Diffusivity, activation energy, permeability, selectivity of gases through porous and non-porous (polymeric, liquid) membranes. Catalytic performance of membrane contactors and membrane reactors
Membrane modules. Cryostat with circulation pump and special membrane modules for measurements below ambient temperature (0-25oC), Cryostat bath for relative permeability measurement at low relative pressures. High sensitivity specific gas analysers (CO2, O2, SO2, H2S) for highly dense-low permeance membranes
Dr. George Romanos (g.romanos@inn.demokritos.gr)