Surface area determination by AS-3600 is a good choice. AS-3600 Surface Area Analyzer works on basis of surface physical adsorption theory, it adopts continuous flow method put forward by Nelsen and Eggertsen. The Helium-nitrogen mixture is input into the sample tube (Helium: nitrogen = 4:1, helium as the carrier gas, nitrogen adsorption gas). The sample tube is then immersed in liquid nitrogen, under the action of low temperature, the nitrogen is physically adsorbed by the sample until getting saturated, after that increase the temperature to completely exit absorbed nitrogen. Thermal conductivity detector in the equipment detects the ratio change of nitrogen in the mixture during adsorption and desorption process, the analog-digital conversion system transfers the analog signals to digital signals and is processed by the computer to calculate the surface area of tested samples on basis of BET Theory of multilayer adsorption and formula.
2.SSA range:0.01㎡/g ≤ X㎡/g ≤ 3500㎡/g
3.Baseline stability line: baseline drift per half hour,shorter than 0.1mv,noise less than or equal to 0.05mv
4.Sampling frequency: 100Hz
5.Minimum peak width: 0.1min
6.Minimum peak height detection limit: 20uV
7.Requirements of gas purity:
Adsorbate—nitrogen ，Purity of 99.99%
The carrier gas—Helium，Purity of 99.99%（if use hydrogen,purity of 99.99% and note that no action between tested samples and the hydrogen)
8.Power: AC 220v±10%/115V (optional converter) 50Hz power less than or equal to 200 W
9.Dimensions: 600mm L x 380mm W x 410mm H
10.Weight: 50 KG/110 lb
Processor: Pentium 3 or above
Memory: 64MB or above
Monitor: High-resolution color display
Operating system: Windows98/XP/2000
-Fully Automation: Whole computer manipulation and graphic interface operation avoids abuse by manual operation.
-Good Accuracy: highly precise 24 A / D converter, linearity test on voltage/surface area with discrete points above 2000.
-High precision: Critical lag technique of Adjustable integrator simulates multi-point BET intercept in order to get higher precision.
-Low data error: Thermal conductivity cell is equipped with high-accuracy signal measurement system made up of foreign brand sensor as well as patented digital-analog conversion system made up of self-developed software work together in order to avoid data errors due to manual measurements by drawing record therefore the repeatability is increased up to less than 2%
-Reliability: Unique high sensitivity built-in airflow controller and signal auto-calibration technology ensure consecutive long-term precision
-Long working life: The unique design of the super-stable thermal conductivity detector ensures that equipment work smoothly for many years
-Closed fast connection device: It ensures the steady state of the class in the powder sample in the sample tube. When the gas from the degassing station transfers to the analysis station, it prevents the powder from getting out of the sample tube and prevents pollution. It ensures that the sample tube can be used for a long time at the same time makes for easy installation, removal, filling and cleaning.
-High efficiency: patented design uses a small amount of continuous airflow to drive the system, quickly reach equilibrium to avoid time delay due to measurement volume. Analysis time is greatly shortened and data accuracy is ensured. It makes for the production line monitoring.
-Safety: Automatically expire protection device. Liquid nitrogen bath safe tray lifting devices.
-Easy to use: Self-developed operating software is easy to learn, contribute to interpretation and output specification format of data reporting.Inexperienced operator can learn how to use AS-3600 in a short time and become skillful after several operations.
-Uitability: in addition to nitrogen, user can use other non-corrosive gases such as argon and helium, user can select right adsorbent concentration in order to get similar results to Multi-point BET test method.
-Applications: Catalysts, adsorbents, fillers, ceramics, carbon black, coke, fiber, minerals, nuclear fuel, medicines, soil, fertilizers, cosmetics etc.
-Sample tubes types: Different types can be used to measure the irregular samples such as those in shape of granular, flake, fiber, patch etc.