ChemiSorb 2720 & 2750
Basic Dynamic Chemisorption Analyzer
- Entry level pulse chemisorption and TPR, TPO, & TPD analyzer
- Rapid BET and metal surface area, metal dispersion and crystallite size measurements of catalysts
- Optimized for research, development, and quality control applications
The ChemiSorb 2720 and ChemiSorb 2750 can be equipped to perform chemical and physical adsorption tests that are central to the development, testing, and production of catalysts. ChemiSorb 2720 and 2750 apply the dynamic chemisorption method, employing a high sensitivity Thermal Conductivity Detector (TCD) for the accurate quantification of the gas chemisorbed by the catalyst. Chemisorption data are reliably converted to catalysts key parameters : metal dispersion, active surface area, , average crystallite size, surface acidity or basicity, and activation energy. In addition, catalysts can be tested in situ by a rapid BET total surface area measure, monitoring possible changes in the sample microstructure.
The ChemiSorb 2720 is an entry level chemisorption and physisorption analyzer ideal for pulse chemisorption, single point BET surface area and total pore volume measurements. ChemiSorb 2720 features a single port dedicated to sorption analysis and a second independent port designed for sample preparation. It also features a built-in cooling fan to accelerate the sample cooling after a high temperature activation, four carrier gas inlets, one prep gas inlet, and the optional capability to accommodate a mass spectrometer or other external detector attached at the exhaust port. Hands-on calibration and dosing procedures make it an excellent teaching tool for gas-solid surface interaction studies.
The ChemiSorb 2750 has been further enhanced with the addition of an injection loop valve for pulsing active gases on the catalyst and features an enhanced dual-port design that allows in-situ preparation and analysis of two samples. Both sample ports can be used as either an analysis port or a degas port, eliminating the need to move the sample thus reducing the chances of contaminating the catalyst during transfer and saving valuable lab time.
An optional ChemiSoft TPx System (temperature-programmed controller and software) expands the capabilities of the ChemiSorb 2720 and 2750 to include temperature-programmed reduction, oxidation, and desorption (TPR,TPO,& TPD). The ChemiSoft TPX software includes advanced data reduction and reporting options.
Features and Benefits:
- Dual port for sample preparation and analysis increases throughput by activating a catalyst while analyzing a different sample
- Fast sample cooling to ambient conditions after activation at high temperature reduces the time for an analysis.
- Optional interface to an external detector such as a mass spectrometer improves the detection capability
- Enhanced analytical versatility with the optional ChemiSoft TPx System
Specifications
ChemiSorb 2720
ChemiSorb 2720 Specifications
Sample Parameters
| Active Gas Volume | Minimum: 0.001 cm³ Maximum: Greater than 10 cm³ |
| Active Specific volume | Minimum: 0.0001 cm³/g Maximum: Greater than 20 cm³/g |
| Surface Area | Minimum: 0.2 m² Maximum: 199.9 m² |
| Specific Surface Area | Minimum: 0.02 m²/g Maximum: Limited only by weighing of sufficiently small sample |
| Pore Volume | Minimum: 0.0001cm³ Maximum: 0.15cm³ |
| Sample Size | Up to 1 cm³ diameter x 3 cm³ length |
| Sample Ports | One dedicated sample port and one dedicated analysis port |
| Throughput | Active Volume: Depends on injection steps; typically 1 to 2 hours per sample Surface Area: Typically 12 minutes per sample Total Pore Volume: Typically 45 minutes per sample |
| Preparation Temperature | 35 to 400 °C with heating mantle |
Accuracy/Reproducibility
| Active Volume | Low and Moderately Low: Typically better than ± 2% with ± 0.5% reproducibility High: Typically better than ± 1.5% with ± 0.5% reproducibility |
| Surface Area | Low and Moderately Low: Typically better than ± 3% with ± 0.5% reproducibility High: Typically better than ± 2% with ± 0.5% reproducibility |
Supplies
| Gas | Ammonia, carbon monoxide, hydrogen, nitrous oxide, and oxygen. Mixtures, with helium, of nitrogen, argon, krypton, ethane, n-butane, and other non-corrosive gases.
A mixture of 30% N₂ and 70% He is recommended for single-point analyses. Mixtures of He and approximately 5, 12, 18, and 24% N₂ are suggested for multi-point use. |
| Coolant | Liquid nitrogen or argon, solvent slush baths, ice water as appropriate for adsorbate |
Exposed Materials
| Sample Tube | Quartz (Chemisorption); Borosilicate (Physisorption) |
| Exposed Materials | Stainless steel, borosilicate glass, Buna-N, rhenium passivated tungsten filament, PEEK, teflon, nickel, silicone (septum). Brass and copper for the inert gas paths |
Operating Environment
| Temperature | 15 to 35 °C (59 to 95 °F) operating; 0 to 50 °C (32 to 122 °F) storing or shipping |
| Humidity | 20 to 80% relative, non-condensing |
Electrical
| Voltage | 100, 120, 220 or 240 VAC ± 10% |
| Frequency | 50/60 Hz |
| Power | 1.25 A (100/120 VAC) 0.75 A (220/240 VAC) |
Physical
| Height | 53 cm (20.9 in.) |
| Width | 46.5 cm (18.3 in.) |
| Depth | 30.5 cm (12 in.) |
| Weight | 18 kg (40 lbs) |
ChemiSorb 2750
ChemiSorb 2750 Specifications
Sample Parameters
| Active Gas Volume | Minimum: 0.001 cm³ Maximum: Greater than 10 cm³ |
| Active Specific volume | Minimum: 0.0001 cm³/g Maximum: Greater than 20 cm³/g |
| Surface Area | Minimum: 0.2 m² Maximum: 199.9 m² |
| Specific Surface Area | Minimum: 0.02 m²/g Maximum: Limited only by weighing of sufficiently small sample |
| Pore Volume | Minimum: 0.0001cm³ Maximum: 0.15cm³ |
| Sample Size | Up to 1 cm³ diameter x 3 cm³ length |
| Sample Ports | Two sample preparation/analysis ports |
| Throughput | Active Volume: Depends on injection steps; typically 1 to 2 hours per sample Surface Area: Typically 12 minutes per sample Total Pore Volume: Typically 45 minutes per sample |
| Preparation Temperature | 35 to 400 °C with heating mantle |
| Gas Injection Loop Capacity |
100μL, 500μL, 1000μL supplied as standard set with instrument; other sizes available |
Accuracy/Reproducibility
| Active Volume | Low and Moderately Low: Typically better than ± 2% with ± 0.5% reproducibility High: Typically better than ± 1.5% with ± 0.5% reproducibility |
| Surface Area | Low and Moderately Low: Typically better than ± 3% with ± 0.5% reproducibility High: Typically better than ± 2% with ± 0.5% reproducibility |
Supplies
| Gas | Ammonia, carbon monoxide, hydrogen, nitrous oxide, and oxygen. Mixtures, with helium, of nitrogen, argon, krypton, ethane, n-butane, and other non-corrosive gases.
A mixture of 30% N₂ and 70% He is recommended for single-point analyses. Mixtures of He and approximately 5, 12, 18, and 24% N₂ are suggested for multi-point use. |
| Coolant | Liquid nitrogen or argon, solvent slush baths, ice water as appropriate for adsorbate |
Exposed Materials
| Sample Tube | Quartz (Chemisorption); Borosilicate (Physisorption) |
| Exposed Materials | Stainless steel, borosilicate glass, Buna-N, rhenium passivated tungsten filament, PEEK, teflon, nickel, silicone (septum). Brass and copper for the inert gas paths |
Operating Environment
| Temperature | 15 to 35 °C (59 to 95 °F) operating; 0 to 50 °C (32 to 122 °F) storing or shipping |
| Humidity | 20 to 80% relative, non-condensing |
Electrical
| Voltage | 100, 120, 220 or 240 VAC ± 10% |
| Frequency | 50/60 Hz |
| Power | 1.25 A (100/120 VAC) 0.75 A (220/240 VAC) |
Physical
| Height | 53 cm (20.9 in.) |
| Width | 46.5 cm (18.3 in.) |
| Depth | 30.5 cm (12 in.) |
| Weight | 22 kg (48 lbs) |
Technology
The ChemiSorb 2720
The ChemiSorb 2720
Versatility in an Inexpensive Chemisorption System
This basic system without the TPx option makes chemisorption and physisorption analyses affordable to even the most modestly funded laboratories. The instrument rapidly and accurately performs pulse chemisorption studies and surface area analyses. The ChemiSorb 2720 features one port dedicated to performing the sorption analysis and a second port designed for sample preparation. It also features a built-in cooling fan for the sample port, four carrier gas inlets, one prep gas inlet, and the optional capability to accommodate a mass spectrometer or other external detector attached at the exhaust port. In addition to chemisorption experiments that include determining the percent metal dispersion, active metal area, crystallite size, and quantifying acid and base sites, a range of physisorption experiments including BET surface area, Langmuir surface area, and total pore volume can also be conducted. Hands-on calibration and dosing procedures make it an excellent teaching tool for gas-solid surface interaction studies.
The basic instrument (without the ChemiSoft TPx option) provides two ways to collect data: 1) via a front panel meter that may be calibrated to display gas volumes adsorbed onto or desorbed from a sample, and 2) by a chart recorder monitoring the analog output from the thermal conductivity detector.
- Dual ports, one for analysis and one for sample preparation.
- Built-in sample cooling fan, four carrier gas inlets, and one prep gas inlet.
- The basic instrument can measure percent dispersion, active metal area, crystallite size, and quantify acid and base sites using pulse chemisorption. Physisorption tests include BET and Langmuir surface area,and total pore volume.
- An optional access fitting allows the ChemiSorb to utilize a mass spectrometer or other external detector for identification of desorbed species or reaction products.
The ChemiSorb 2750
The ChemiSorb 2750
Higher Precision and Versatility
The ChemiSorb 2750 (built upon the same design elements as the Chemisorb 2720) has been further enhanced with the addition of an injection loop for pulsing active gases on the catalyst and features an enhanced dual-port design that allows in-situ preparation and analysis of two samples. Its dual-function sample ports have the capability to be used as either an analysis port or a degas port, eliminating the need to move the sample. This requires less effort and reduces the chances of contaminating an activated sample from exposure to stray gases.
Performing different types of analyses is also easier. In addition to the four carrier gas inlets and three preparation gas inlets, a dedicated gas inlet for the pulse chemisorption gas has been added. Thus the increased number of ports provides a rapid method for gas change overs without the need to manually disconnect, reconnect, and purge gas lines; this further minimizes the risk of contamination and improves the ease of operation.
Higher precision, repeatability, and reproducibility are provided by the incorporation of an injector loop valve in addition to the injection septum. The loops are easily exchanged to provide different injection volumes. Electrically activated inlet valves allow the use of gases containing H2, CO,O2, N2O, NH3, liquid vapor sources, or other adsorptives. Three built-in prep gas inlets and four carrier gas inlets allow for a variety of experiments without having to disconnect, reconnect, and purge gas lines.
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 primarily the desired product. Chemisorption experiments are valuable for the selection of catalysts for a particular purpose, qualification of catalyst vendors, and the testing of a catalyst’s performance over time to establish when the catalyst should be reactivated or replaced.
Fuel Cells – Platinum-based catalysts including Pt/C, PtRu/C, and PtRuIr/C may be characterized by temperature-programmed reduction to determine the number of oxide phases or by pulse chemisorption to characterize the metal surface area, metal dispersion, and average crystallite size.
Partial oxidation – Manganese, cobalt, bismuth, iron, copper, and silver oxides are often used for the gas-phase oxidation of ammonia, methane, ethylene, propylene, etc. Temperature-programmed oxidation and temperature-programmed desorption may be used to measure the heat of desorption of oxygen from these catalysts and the heat of dissociation of oxygen from the metal oxide.
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.
Catalytic-reforming catalysts containing platinum, rhenium, tin on silica, alumina, or silica-alumina are used for the production of hydrogen, aromatics, and olefins. These catalysts are often characterized using pulse chemisorption techniques to determine the number of active sites, the percent metal dispersion, and average crystallite size. Isomerization catalysts such as smallpore zeolites (mordenite and ZSM-5) containing noble metals (typically platinum) are used to convert linear paraffins to branched paraffins and thus increase the octane number and value for blending gasoline. Temperature-programmed reduction and pulse chemisorption are often combined to characterize these catalysts.
Hydrocracking, hydrodesulfurization, and hydrodenitrogenation catalysts are typically composed of metal sulfides (nickel, tungsten, cobalt, and molybdenum). Hydrocracking catalysts are used for processing feeds containing polycyclic aromatics that are unsuitable for typical catalytic cracking processes. The hydrocracking process is used for upgrading these low-value products to gasoline and diesel fuel. Hydrodesulfurization and hydrodenitrogenation are used for removing sulfur and nitrogen, respectively, from petroleum feeds. Both sulfur and nitrogen are catalytic poisons and also are the source of pollution (acid rain) if they are not removed from gasoline and diesel fuel. Temperature-programmed reduction and oxygen chemisorption are used to characterize the oxide phases and active surface area of these materials.
Fischer-Tropsch synthesis uses cobalt and iron-based catalysts to convert syngas (carbon monoxide and hydrogen) to hydrocarbons larger than methane. The Fischer-Tropsch processes are of great importance as they provide hydrocarbons that are rich in hydrogen and do not contain sulfur or nitrogen. These hydrocarbons are a potential liquid fuel that is easily transported and distributed, and can then be reformed to hydrogen to supply fuel cells. These catalysts are often characterized by pulse chemisorption and temperature-programmed desorption to determine the metal surface area and the average size of the metal crystallites.
Optional ChemiSoft TPx System
Quote Accessories
Optional ChemiSoft TPx System (temperature-programmed controller and software) expands the capabilities of the ChemiSorb 2720 and 2750 to include temperature-programmed reactions, data archiving, and advanced data reduction and reporting options
Expanded physisorption capability includes multipoint BET surface area.
ChemiSorb 2720 & 2750 Resources
ChemiSorb 2720 & 2750 Photo Gallery
