Model : AI 1200
Elemental analysis is a process where a sample of material (eg. soil, waste or drinking water, bodily fluids, minerals, chemical compounds) is analyzed for its elemental composition.
Analytical chemistry is the analysis of material samples to gain an understanding of their chemical composition and structure.
Atomic absorption spectroscopy in analytical chemistry is a technique for determining the concentration of a particular metal element within a sample. Atomic Absorption Spectroscopy can be used to analyze the concentration of over 62 different metals in a solution.
Typically, the technique makes use of a flame to atomize the sample, but other atomizers such as a graphite furnace are also used. Three steps are involved in turning a liquid sample into an atomic gas:
Desolvation – the liquid solvent is evaporated, and the dry sample remains
Vaporization – the solid sample vaporizes to a gas
Volatilisation – the compounds making up the sample are broken into free atoms.
The flame is arranged such that it is laterally long (usually 10cm) and not deep. The height of the flame must also be controlled by controlling the flow of the fuel mixture. A beam of light is focused through this flame at its longest axis (the lateral axis) onto a detector past the flame.
The light that is focused into the flame is produced by a hollow cathode lamp which is the most common light source used in atomic absorption (AA) spectroscopy. The wavelength and intensity of light is dependant on the metal. Therefore, analysis by atomic absorption spectrometer requires a specific lamp for each element to be measured.
As the quantity of energy inputted into the flame is known, and the quantity outputted at the other side (detector) can be measured, it is possible to calculate how many of these transitions took place, and thus get a signal that is proportional to the concentration of the element being measured.
* SPECTROMETER :
- Optics : High light throughput single/double switchable optics, including low UV range. Narrow beam optical design for flame and furnace configuration. Aberration corrected 30cm Czerny-Turner monochromator with software controlled wavelength selection and optimization.
- Dimensions : W65 x D55 x H37cm
- Band Pass : Software adjustable 0.2, 0.6 and 1.2nm (0.6nm reduced slit height)
- Grating : 53mm x 53mm diffraction grating with 1200 lines/mm
- Wavelenght range : 185-900nm controlled by software
- Wavelenght scan/ optimization : From 185-900nm in any selected range with Zoom function. Automatic wavelength optimization with graphical display.
- Background correction : Rapid self-reversal method. Deuterium lamp with 1ms rapid response for accurate correction. Electronic modulation wuth deuterium current control and aperture attenuation.
- PMT : High quantum efficiency from 185-900nm, automatic gain control
- Drift correction : Automatic drift correction permits the full intensity of the light beam to pass through the sample resulting in superior detection power. No HCL preheat is required.
- Data sampling rate : D2 and hollow cathode lamps operate at 1000Hz data sampling rate.
- Light source : 5 lamps motorized turret with independent power supply.Automatic alignment and coded lamp selection.
- Built – in high intensity : 2 channel independent high intensity power supply.
- Hollow cathode lamps : Provides improved sensitivities and lower detection limits.
* ATOMIZERS :
- The configuration of the atomization compartment allows rapid changeover between atomization sources.
FLAME :
- Gas control : Software controlled with automatic changeover between different flame systems.
- Spray Chamber : Solid Teflon spray chamber ,inert to acids and organic solvents.
- Burner : Corrosion resistant Titanium burners for both air/acetylene and nitrous-oxide/acetylene.
- Gas requirements : 1.Air-dry, oil and dust free @ 50-80 psi. Typical flow rate 10-12L/min.
2. Acetylene (99% pure) @ 8-10 psi. Typical flow rate 0.5-8L/min
3. Nitrous-oxide (99.5% pure) @ 50-80 psi.Typical flow rate 10-12 L/min.
- Flow-rate / Control : Software controlled.
- Sample introduction : Automatic on –line dilution and preparation of calibration curves from a single standard .
- Fume exhaustion : Conventional laboratory extraction system.
- Safety system : Safety interlock mechanism that monitors the burner type, burner fitted, gas pressures.Flame on/off sensors, power failure automatic shutdown.Liquid trap system, pressure relief plug and flame shield to protect from UV radiation.
* TRANSVERSELY – HEATED GRAPHITE FURNACE :
- Purge gas : Computer controlled flow rate of Ar or he from 0 to 5.0 L/min.
- Furnace tube : Pyrolytically coated integrated contact cuvette, 5.7mm internal dia x 19mm, transversely heated, temperature gradient of less than 20 oC
- Temperature range : Programmable from ambient up to 3000 o C. Full range temperature sensors for direct real-time temperature display and control over the full temperature range.
- Furnace heating rate : Up to 3800K/s
- Program flexibility : Heating programs of up to 30 steps. Each step can be programmed separately.
- Ramp time : The heating time of the graphite tube to the preprogrammed temperature can be varied in steps of 0.1s.
- Hold time : Selectable from 0 s up to 25s in steps of 0.1s
- Safety : Gas and cooling water safety interlocks.
* VAPOR AND HYDRIDE GENERATOR :
- Absorption cell : Constant temperature electrothermally heated quartz absorption cell with temperature range of ambient to 1000oC.
- Pump : Continuous flow peristaltic pump with speed control.
- Accessories : High efficiency mixing section, gas – liquid separator, tubing and connectors included.
- Performance : Cold vapor and hydride generation determinations of Hg, As, Se, Te, Bi, Sb,Sn and other hydride-forming metals at sub-trace levels.
* AUTOSAMPLER :
- Optional flame/ VG XYZ Autosampler :
- Autosampler design : Free movement in XYZ directions, Adapt to any sample container.
- Sample introduction : When combined with on-line dilution of over-range samples.
* ONE FOR ALL XYZ AUTOSAMPLER :
- Dispensable reagent volume : Up to 1000uL, selectable in increments of 1uL
- Sampling capacity : holds standard 192 sample cup/test tube (0.5 or 10mL) sample racks. Also compatible with standard solvent extraction test tubes, ICP test tubes, micro plates and custom made trays.
- Super Fast-Dry function : software controlled preheating and sample injection speed.Allows for 3 sample/min turn-around time with GF.
- Sample Introduction : Random access with adjustable sample/reagent volume, automatic standard and sample preparation, standard addition and spike.
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