Fluorescent light tube

California and Minnesota have placed restrictions on the disposal of fluorescent light tubes, which contain from 40—50 mg of mercury per tube, depending on size. After batteries, fluorescent lamps are the second largest contributor of mercury in soHd waste streams in the United States (3,14). A California law classifies the disposal of 25 or more fluorescent lamp tubes as hazardous waste. In Minnesota, all waste lamps generated from commercial sources are considered hazardous waste. Private homes are, however, exempt from the law (14). Other states have proposed similar regulations. Several companies have developed technologies for recovering mercury from spent lamps (14). 

The electrical uses of mercury include its application as a seal to exclude air when tungsten light bulb filaments are manufactured. Fluorescent light tubes and mercury arc lamps that are used for street lighting and as germicidal lamps also contain mercury. 

There are only a few commercial uses for europium. Europium oxide, (Eu O ), a compound of europium, is added to infra-sensitive phosphors to enhance the red colors on TV and computer-monitor picture tubes. It is also added to fluorescent light tubes to increase their efflciency, as well as to some materials to make lasers. Since it is a good neutron absorber, it is part of nuclear reactor control rods. Europium is an additive to the glue used on postage stamps, thus making it possible for the electronic sorting machines in U.S. postal offices to read the stamps. 

Phosphors are solids which absorb energy and re-emit it as light. As in the lasers we have just described, the emitter is usually an impurity ion in a host lattice. However, for the uses to which phosphors are put it is not necessary to produce intense, coherent beams of light, and the emitting process is spontaneous instead of induced. Phosphors have many applications, for example, the colours of your television picture are produced by phosphors that are bombarded with electrons from a beam (cathode rays) or from a transistor (flat screen LCD displays). In terms of tonnage produced, one of the most important applications is the fluorescent light tube. 

Spent fluorescent lamps, as well as mercury vapor lamps, contain sufficient mercury to qualify as toxic hazardous wastes under Section 66699 (b) of the California Code of Regulations (CCR). At present, a generator may dispose of no more than 25 spent fluorescent light tubes and/or mercury vapor lamps at a time, regardless of size. The EPA, too, has concluded that fluorescent lamps can in sufficient quantities be considered hazardous waste under 40 CFR 261.24 (Quicksilver 1989). 

Une proprietary lamp is similar lo the ordinary fluorescent lighting tube, but contains a phosphor that emits an abundance of radiation in the 350- to 360-mg region of the spectrum. These lamps are usually of 5 or 15 watts and operate with a simple starter and ballast. The phosphor emits visible light, which must be excluded by a filter. Mercury vapor lamps provide the... 

Drug photosensitivity means that an adverse effect occurs as a result of drug plus Ught, usuaUy UVA sometimes even the amount of ultraviolet radiation from fluorescent light tubes is sufficient. 

Kirschner DS, Billau RL, MacDonald TJ. 1988. Fluorescent light tube compaction Evaluation of employee exposure to airborne mercury. Appl Ind Hyg 3(4) 129-131. 

Use Incandescent bulbs and fluorescent light tubes, lasers, high-speed photography. Note Solid krypton exists at cryogenic temperatures as a white, crystalline substance mp 116K. 

Use Fluorescent light tubes television, radar, and cathode ray tubes, instrument dials, scintillation counters. 

Fluorescent Light Tube cury atoms and excite their electrons to high-... 

Plant Care How could fluorescent light tubes be altered to supply indoor lighting in the blue and red region of the visible spectrum for raising plants ... 

PCBs Defective electrical capacitors, e.g. in fluorescent light tubes Defective electrical transformers Paintings and varnishes containing flame retardants Plasticizers in sealing materials Wood protection agents... 

Another extensively investigated trivalent cation in apatites is Sb, because Sb-doped FAp acts as an activator in fluorescent-light tubes (e.g., Davis et al. 1971 Soules et al. 1971 Mishra et al. 1987 DeBoer et al. 1991 Moran et al. 1992). Rietveld XRD refinements of a FAp powder sample with 2.2 wt % Sb suggested that is ordered at the Ca2 site (DeBoer et al. 1991), consistent with the site occupancy deduced from excitation and emission spectra of Sb-doped ClAp and FAp (Davis et al. 1971 Soules et al. 1971). However, the same study on a different sample containing 3.1 wt % Sb did not find any evidence for substitution at the Ca2 site but suggested, on the basis of electron density maps, that the Sb ions occupy the (1/3,2/3,1/4) and (2/3,1/3,1/4) sites (DeBoer et al. 1991). Also, the Ca2 site assignment for Sb ions is not consistent with results from Sb Mossbauer (Mishra et al. 1987) or F and MAS NMR studies (Moran et al. 1992 see below). 

Lanthanide elements are used for miscellaneous purposes (i) and recently they are used as additives in fluorescence light tubes to improve their spectra. Additionally, recycling of fluorescence light tubes has just started because mercury is contained in the tubes. A new method of recovering lanthanides is required to improve economical aspect of the recycle. 

Lanthanide metals were also successfully extracted from their oxides with a high pressure mixture of TBP-HNO3-H2O-CO2 (12). We applied this technique to extract europium from the additives contained in fluorescence light tubes. The additives were recovered as white powder by crashing the glass tubes. An experimental study was performed with a similar apparatus as shown in Figure 6. The results of extraction of europium are given in Table 1 as well as the experimental conditions. In Ref. (12), the recovery yield approached 100% easily, but relatively low recoveries... 

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