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Rare earth elements in electronic waste
Pospíšilová, Eliška ; Šebek, Ondřej (advisor) ; Strnad, Ladislav (referee)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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Elemental analysis of the flat display devices for urban mining
Štípek, Radek ; Strnad, Ladislav (advisor) ; Mihaljevič, Martin (referee)
aaaaaRare earth elements (Sc, Y and group 15 lanthanides) and their compounds currently have significant practical use in metallurgy, glass industry, as highly active catalysts for the production of so-called. NiMH batteries, alloys for the manufacture of permanent magnets and e.g. moderators rods in the nuclear energy, but above all they have an irreplaceable role in modern electronics for phosphors TV screens, CRT earlier today, PDP and LCD monitors and displays, tablets, mobile phones etc., which give them a high-quality picture and sound. Unlike most base and precious metals are concentrated in the conquerable ore deposits, occur in the form of compounds as part of mixed minerals in the rarely economically exploitable concentrations, a mining and processing is costly and negative impacts on the environment, paradoxically towards the title but their overall content in the crust is relatively high, the average concentration in the range of about 150 to 220 ppm. The main world producer of REE, China, in 2010, significantly reduced exports by 40 %, making prices of some REE increased up to 1500 % during the month. Demand for REE is growing, so often talks about the recycling of valuable materials back into production, as called. "Urban mining", ie "urban mining", thereby reducing the amount of...
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Rare earth elements in electronic waste
Pospíšilová, Eliška ; Šebek, Ondřej (advisor) ; Strnad, Ladislav (referee)
Rare earth elements consist of 15 lanthanides, Y and Sc. They are currently very important materials in many industrial branches (metalurgy, pollishing). One of these options is the usage as the compound of phosphors in electronic devices (television and computer displays. Because of their manufacturing cost, options of recovery from waste electrical and electronic equipment (WEEE) are investigated. This thesis deals with compoud elements of phosphors from displays of type CRT (cathode ray tube) and plasma TV. The 37 samples of phosphors from different displays were taken and processed for study of the compoud elements. Phosphors were separated to 4 subgroups in accordance with the corresponding type of displays: black-and-white CRT television displays (CRT_CB), color CRT television displays (TV_B), color PC displays (PC_B) and monochromatic PC displays (PC_M). The study was carry out by multiple features analysis that combined the inductively coupled plasma mass spectrometry (ICP-MS), the inductively coupled plasma optical emission spectrometry (ICP-OES), the resistance furnace with infrared detector (RF-IF) and the atomic absorption spectrometry (AAS). Based on the results of this analysis, main elements and potentionally hazardous elements of phosphors subgroup were defined. Concentration of rare...
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