Alex Stewart International Spain
Our chemical analysis laboratory combines traditional wet chemistry methods with modern state of the art laboratory instrumentation to provide a fast, reliable and accurate results for commercial metal analysis.
Inductively Coupled Plasma Optical Emission Spectroscopy, precise analysis of a wide range of elements up to trace levels.
Emission spectroscopy is an instrumental technique that has been positioned within the most versatile measurement techniques, because it has the ability to simultaneously measure more than 80% of the elements of the periodic table.
Likewise, the ability of modern equipment to reach quantification limits in the sub-ppm range makes them practically essential in any chemical analysis laboratory. Among its most notable qualities are the versatility, the accuracy and repeatability of the results and the high sample throughput.
In this technique the sample is introduced to the equipment continuously in liquid form. The sample is converted into a spray and transported by a pure Argon flow to the equipment torch, where it enters the plasma generated by radio frequency. In it, high temperatures atomize and ionize the analytes, generating the emission atomic spectra characteristic of each chemical element. The spectrometer is responsible to recording and measuring the emission spectra and software to calculate and display the obtained data.
Combustión and infrared detection analyzer for Carbon and Sulfur, accurate determinations from trace levels to high concentrations.
The LECO Carbon and Sulfur analyzer allows rapid and exceptionally accurate analysis in a wide range of inorganic samples. It is a system that melts the sample in a flow of pure oxygen to later read the amount of SO2 and CO2 emitted in the infrared region.
Combining wet and dry digestion methods with state-of-the-art assessment equipment and gravimetric techniques, we cover a wide range of concentrations, analytes and sample types, with reliable and accurate results.
Fusion / cupellation method for determination of precious metals such as Gold, Silver and metals of the Platinum group.
The beginnings of the fire assay for the recovery of precious metals date about 2000 years ago. Obviously the techniques used have varied a lot in all these years, but the basis of the technique is the same as then.
High temperatures and a mixture of suitable fluxes are used to melt the sample and release the precious metals so they can be collected by the lead. In this fusion process two liquid phases are formed, a light and fluid slag and another metallic phase constituted by the lead and the precious metals.
After cooling, the lead button is separated from the slag and the cupellation process is carried out where the sample is subjected to high oxidation temperatures to eliminate the lead and finally obtain the precious metal bead (Gold, Silver and metals of the Platinum group).
The last step would be the determination of the gold content gravimetrically after realizing the partition (separation of the Gold from the rest of precious metals) or the bead can be dissolved for later reading by means of spectroscopic techniques. This achieves really low levels of quantification. It is usually expressed in parts per million (ppm) or in grams per ton (g / t), which is equivalent.
It is important to emphasize the importance of being able to determine gold gravimetrically, something that not all laboratories offer, due to the large amount of sample that must be analyzed in order to determine contents of few ppm by a gravimetric technique. This type of determination offers better levels of precision than acid dissolution and reading techniques in ICP or AA.
X-ray fluorescence spectrometer for high concentrations and traces determination.
The XRF technique is an atomic emission method that allows to measure the emission intensity of the atoms of the sample energized by an X-ray beam.
Its main advantage over other spectroscopic techniques is that the sample is presented in solid, it is not necessary to digest it to pass it to liquid state.
+34 94 447 77 35
Monday to Friday,
8 - 13 and 15 - 18 hrs.
Alex Stewart International Spain
Parque Empresarial Inbisa-Erandio, Sector Q, Nave 14A
48950 Asua-Erandio (Vizcaya)
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