XRF spectrometry is one of the most widely used and versatile analytical technique. An XRF spectrometer normally uses primary radiation from an X-ray tube to excite secondary X-ray emission from a sample. The radiation emerging from the sample includes the characteristic X-ray peaks of major and trace elements present in the sample. Dispersion of these secondary X-ray into a spectrum, usually by X-ray diffraction, allows identification of these elements present in the sample. The height of each characteristic X-ray peaks relates to the concentration of the corresponding element in the sample, allowing quantitative analysis of the sample for most elements. The Solid samples are analysed in the form of pressed powder pellets or homogenised glass fused beeds.
The XRF laboratory at WIHG was established in 1979 with an Energy Dispersive XRF System ( EDAX EXAM SIX) . The System produced useful data upto 1994 when it was replaced with a Siemens SRS-3000 sequential (wavelength dispersive) spectrometer. The Features available in the existing system are -
- End window 3 kW Rh anode tube (60 kV, 100 mA)
- samples or pellets with dia. 23,34 or 40 mm and height upto 51 mm are analysed.
- Nine analysing crystals ( LIF200, LiF220, Ge, PET, OVO-55, OVO-160, InSb and ADP
- X-ray detectors SC and FPC
Elements routinely determined as weight % oxide are
SiO2, TiO2, Al2O3, Fe2O3 (total), MnO, MgO, CaO, Na2O, K2O, and P2O5.
Trace elements routinely determined in geological samples at the> 5 ppm (2 ppm for some elements) level are Ba, Sc, V, Cr, Co, Ni, Cu, Zn,Ga, Pb, Th, Rb,U, Sr, Y, Zr and Nb .
Sample Requirement: Normally in powder form (-200 mesh). Quantity - > 8 g
Sample Preparation Facility available-
Automatic Hydraulic press (40 Ton) for making pressed poder pellet.
Planetary Ball Mill (Reitsch PM-100) for fine powdering.
Claisse Fluxy Fusion beed preparation machine.
Sample Preparation Facilities for XRF analysis
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