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There is a need in the mining industry for determining quickly and in the field the concentration of gold in mineral ore samples. Existent portable analyzers cannot determine the gold content at the ppm range. Hence, a portable LIBS (Laser-Induced Breakdown Spectroscopy) appears as a good candidate but developments are required to fulfill the needs of the gold mining industry. Developing a functional LIBS based analyzer involves several challenges to be addressed prior to its use in the field. To be of practical use, the analyzer has to probe a representative sampling of the surface of the mineral samples and has to tackle the matrix effect resulting from several mineralogical compositions of the samples. This paper presents the recent on-going work at the National Research Council Canada (NRC) and Laval University using LIBS for gold mining, from the determination of gold-bearing rock composition to direct detection of gold and system prototyping., The 56th Conference of Metallurgists COM 2017, August 27-30, 2017, Vancouver, BC, Canada

Scix 2015, Sept. 27 - Oct. 2, 2015, Providence, RI, USA

Québec Mines 2014, Québec City, QC, November 17-20, 2014

The first step in the pyrometallurgical process for extracting copper and nickel from ores consists in melting the ore and skimming the silicates and other oxides that float on the surface. The denser mixture of molten metals and sulfur found at the bottom is called matte. Our industrial partners want to know the concentration of copper, nickel and cobalt in the matte, in real time and in situ in the furnace or immediately at the exit of the furnace when it is tapped. Knowing these concentrations would allow increasing production efficiency in the following processing step, whereby iron and sulfur are oxidized inside a second furnace called the converter. We are developing a laser-induced breakdown spectroscopy (LIBS) sensor to measure online the concentrations of copper, nickel, cobalt, iron and sulfur in the molten matte. The measurement is made through a tube in which an inert gas flows. This allows measuring below the surface slag and impurities. Alternately, we are also investigating direct measurements onto the surface which could be advantageous when the molten matte is flowing in a channel. The advantages of LIBS technology are speed, lower operation costs than the current sampling technique, and improved safety because LIBS does not require manual sampling of molten metals. Preparatory measurements taken in the laboratory at temperatures of approximately 1100 °C will be presented. From an analytical point of view, one difficulty is that there is no major element that can be used to normalize line intensities., Pittcon 2014, March 2-6, 2014, Chicago, Illinois

The International Atomic Energy Agency (IAEA) has the mandate to safeguard the use of uranium, plutonium and thorium worldwide, as nuclear fuel for civil uses, avoiding their diversion use in weapons of mass destruction or explosive devices. Terrorist and proliferation activists are employing more sophisticated means than those used in the past to achieve their objectives. Border security services, first responders and regulators need to adapt to this challenge and to seek technologies that can provide quick and accurate information, in order to prevent clandestine activities or initiate rapid responses to them. Laser-Induced Breakdown Spectroscopy (LIBS) technique has several advantages, the most relevant are real-time measurement, contact with the sample is not necessary, and analysis can be made at a distance avoiding contamination by radioactive materials. LIBS and Partial Least Square – Discriminative Analysis (PLS DA) were used for the origin assessment of uranium ore refining process intermediates for real-time nuclear forensics. A PLS-DA model was built to assess the origin different process intermediate samples. The results obtained suggest the applicability of LIBS to identify the origin of uranium ore refining intermediate. The correctly classified rate for external validation set is better than 96% for the blind validation set. The results obtained with the transportable LIBS unit clearly show the usefulness of this approach for real-time onsite nuclear forensics., FACSS/SciX The Great Scientific Exchange, Milwaukee, USA; Sept. 29 - Oct. 4, 2013

The International Atomic Energy Agency (IAEA) has the mandate to safeguard the use of uranium, plutonium and thorium worldwide, as nuclear fuel for civil uses, avoiding their diversion use in weapons of mass destruction or explosive devices. Terrorist and proliferation activists are employing more sophisticated means than those used in the past to achieve their objectives. Border security services, first responders and regulators need to adapt to this challenge and to seek technologies that can provide quick and accurate information, in order to prevent clandestine activities or initiate rapid responses to them. Laser-Induced Breakdown Spectroscopy (LIBS) technique has several advantages, the most relevant are real-time measurement, contact with the sample is not necessary, and analysis can be made at a distance avoiding contamination by radioactive materials. LIBS and different combination of chemometric techniques were integrated in a portable autonomous system that can perform real-time measurement. In addition, this portable LIBS instrument can be operated by a person that does not required an extensive knowledge of neither spectroscopy nor chemometrics. The present paper describes different applications that are or in the integration process in the portable LIBS unit. In particular, the possibility of analyzing isotope ratio using LIBS, assessment of yellow cake origin as well as discriminating the different compounds found in the uranium ore refining process. The performance obtained with such a LIBS sensor will be discussed for nuclear forensics. The results obtained with the transportable LIBS unit clearly show the usefulness of this approach for real-time onsite nuclear forensics., FACSS/SciX The Great Scientific Exchange, Milwaukee, USA, Sept. 29 - Oct. 4, 2013

Les alliages de Fer sont des matériaux métalliques relativement peu onéreux dont les performances mécaniques satisfont de nombreuses exigences qui peuvent atteindre des niveaux très élevées. La présence d'éléments d'alliages conduit, dans la plupart des cas, à des modifications de la strucutre et du comportement mécanique des métaux. L'importance de vérifier la composition chimique des alliages métalliques a augmenté au fil des ans pour garantir la qualité des produits expédiers (tuyau, fil, plaque, feuille et tôles d'acier) et ainsi minimiser les coûts reliés au retour de marchandise et de réusinage. La spectrométrie laser-plasma (LIBS : “Laser-Induced Breakdown Spectroscopy”) est une technique analytique bien connue qui permet la détection de la plupart des éléments du tableau périodique avec des limites de détection de l'ordre de la partie par million massique (ppm m/m) et ceci sur tous types d'échantillons qu'ils soient liquides, solides ou gazeux. Sa simplicité de mise en œuvre, sa rapidité et sa versatilité en font une technique très attractive avec un fort potentiel pour les applications nécessitant un contrôle en ligne. La forte émergence sur le marché des lasers Ytterbium de grande puissance et compacte permettent d'obtenir sur la cible des densités de puissance de l'ordre de 100 MW/cm2. Cette densité est suffisante et supérieure au seuil d'ablation du matériau ainsi qu'au seuil de claquage (i.e. création du plasma). Lorsque de telles sources sont couplées à des spectromètres de haute résolution, ceci permet d'effectuer des mesures LIBS sur des alliages d'acier. Des courbes de calibrations pour le Mn, Ni, Cr, Si , Cu, V et Ti ont été obtenus avec une reproductibilité sur la mesure site à site de l'ordre de 1%., Spectr'Atom 2013, 25-28 juin 2013, Mont-Tremblant, QC, Canada

Field portable technologies and methods are sought to provide simple, inexpensive, and fast analysis of materials in the mining, construction, and other industries. However, the level of portability needed for this particular application imposes some restrictions on the choice of many of the core components used in low-cost LIBS handheld sensor. This means that relatively low-performance components, such as a low-energy laser source and a low cost, low resolution spectrometer, and working conditions in ambient aire at atmospheric pressure must be considered to fulfil these conditions. In addition, the market price of such a portable device should be affordable or as low as possible to increase the breadth of potential end users and allow the deployment of multiple units for security enhancement. The present paper describes the determination of isotope rations using Laser-Induced Breakdown Spectroscopy in air at atmospheric pressure for partially resolved uranium-235/uranium-238 and hydrogen/deuterium isotope shift lines in such conditions. Using a Partial Least Square (PLS1) regression, it is possible to build a model that enables the accurate determination of the isotopic ration under conditions where the application of traditional univariate approaches for hydrogen and uranium would not be achievable without the use of ultra high resolution spectrometer. In addition, the application of PLS1 regression to determine the uranium-235/uranium-238 and deuterium/hydrogen isotopic rations between 0 and 1 mass fraction was also successfully demonstrated. The performance obtained with such a LIBS sensor will be discussed for nuclear forensics., SciX 2012 - The Great Scientific Exchange, Sept. 29-Oct. 4, 2012, Kansas City, Missouri, USA

2010 Winter Conference on Plasma Spectrochemistry, 2010-01-04, Forth Myers, Floride, USA

Colloque Plasma-Québec 2011, Université de Montréal, Montréal, 2011-05-25, 2011-05-25, Montréal, Qc, Canada

Plasma Québec 2011: Université de Montréal, 2011-05-25, Montréal, Québec, Canada

6th International Conference on Laser-Induced Breakdown Spectroscopy (LIBS 2010), September 13-17, 2010, Memphis, Tennessee, USA

6th International Conference on Laser-Induced breakdown Spectroscopy (LIBS 2010), 2010-09-14, Memphis, Tennesee, USA

Colloque Plasma-Québec, June 1-3, 2010, Montréal, Québec

5th International Conference on Laser-Induced Breakdown Spectroscopy, Berlin, Germany, 2008

6th International Conference on Laser-Induced Breakdown Spectroscopy (LIBS 2010), September 13-17, 2010, Memphis, Tennessee, USA