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Health and Safety Information
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Propanal 1,3-Propane sultone Propanoic acid 1-Propanol 2-Propanol Propargyl alcohol Propene Propoxur Propyl acetate 1,2-Propylene glycol dinitrate Propyleneimine Propyl nitrate Propyne Pyrethrin I 2-Pyridinamine Pyridine Pyrocatechol Resorcinol Rhodium Rhodium Ronnel Rotenone Rubber Selenium Selenium hexafluoride Sesone Silane Silicon carbide (hexagonal) Silicon dioxide (-quartz) Silicon dioxide (cristobalite) Silver Silver Sodium azide Sodium fluoroacetate Sodium hydrogen sulfite Sodium hydroxide Sodium metabisulfite Sodium tetraborate decahydrate Starch Stibine Stoddard solvent Strontium chromate Strychnine Styrene Subtilisins Sucrose Sulfometuron methyl Sulfotep Sulfur chloride [SSCl2] Sulfur decafluoride Sulfur dioxide Sulfur hexafluoride Sulfuric acid Sulfur tetrafluoride Sulfuryl fluoride Sulprofos Talc Tantalum Tantalum(V) oxide Tellurium Tellurium hexafluoride Terbufos Terephthalic acid o-Terphenyl m-Terphenyl p-Terphenyl 1,1,2,2-Tetrabromoethane Tetrabromomethane 1,1,1,2-Tetrachloro-2,2-difluoroethane 1,1,2,2-Tetrachloro-1,2-difluoroethane 1,1,2,2-Tetrachloroethane Tetrachloroethene Tetrachloromethane 1,2,3,4-Tetrachloronaphthalene Tetraethyl lead Tetraethyl pyrophosphate Tetrafluoroethene Tetrahydrofuran Tetrakis(hydroxymethyl)phosphonium chloride 2,2,3,3-Tetramethylbutane Tetramethyl lead 2,2,3,3-Tetramethylpentane 2,2,3,4-Tetramethylpentane
Heavy-Media Separation
Published in S. Komar Kawatra, Advanced Coal Preparation and Beyond, 2020
Organic heavy liquids are generally halogenated hydrocarbons, such as perchloroethylene, carbon tetrachloride, bromoform, and tetrabromoethane, although lower-density organic liquids, such as gasoline and benzene, are also sometimes used. The heavy liquids that are most commonly used are given in Table 4.9. These have specific gravities as high as 3.31 and have the advantages that they are stable, immiscible with water, have low viscosities, and the specific gravity of the liquid can be easily regulated by mixing the liquids in the proper proportions. Their disadvantages are that they are for the most part very toxic and quite expensive. As a result, these liquids are used exclusively for laboratory sink–float analyses and other quality-control applications, although some pilot-scale attempts have been made to develop an industrially practical separator based on true heavy liquids. One of the more successful attempts was the Otisca process, which used trichlorofluoromethane (Freon-11) as the heavy liquid (Keller, 1982). This liquid had the advantage that it was essentially nontoxic and could be easily recovered by evaporation because of its low boiling point. Because of concerns about its effect on atmospheric ozone, use of freon on an industrial scale has been heavily regulated, and it is unlikely that it would be possible to use it for coal cleaning. More recent work has been conducted using methylene chloride/tetrachloroethylene mixtures (Durney et al., 1991, 1992), which are reported to work well in the laboratory, but are toxic. However, at a plant scale, methylene chloride dissolved the pump seals, spilled all over the floor, and was not tried again.
Drilling Holes in Ice Sheets
Published in B.B. Kudryashov, A.M. Yakovlev, Drilling in the Permafrost, 1991
B.B. Kudryashov, A.M. Yakovlev
Results of investigations showed that the components were highly miscible, fairly stable at low temperatures and did not show any noticeable interaction with ice or water. When the density of the solutions is increased by raising their tetrabromoethane and freon-11 concentration, the increase in viscosity is not very significant even at lowest negative temperatures. This ensures low hydraulic resistance for the fluid during its circulation at the hole bottom zone and during the lifting and lowering operations of the drill tool.
Properties and reactivity of two oxidized and unoxidized South African Highveld fine coal rejects and their density-separated fractions
Published in International Journal of Coal Preparation and Utilization, 2023
K Mphahlele, R. H. Matjie, J. R. Bunt, R.C. Uwaoma
About 25 kg each of the TEP and STEM samples were beneficiated using the density separation technique to produce: floats (Fl1.5) with an average density (ρa) of <1.5 g/cm3; middling (Fl1.9) at 1.5 < ρa <1.9 g/cm3 and sink (SI1.9) obtained at sp. >1.9 g/cm3 at General Society of Surveillance (SGS) Laboratories (PTY) Ltd, following the procedures described in ISO 7936 standard method. Tetrabromoethane, benzene and tetrachloroethylene, with respective ρa of 2.95, 0.879 and 1.62 g/cm3, were used as mixtures to produce 1.5, 1.5–1.9 and 1.9 g/cm3 density floats and sink fractions, as indicated by Everson et al. (2013) and Rautenbach et al. (2019). Acetone was used to wash density separated samples. The washed samples were air-dried for 10 hours to remove any acetone absorbed on the surface of coal particles Furthermore, acetone-washed density separated fractions were dried at 80 °C for further 24 hours to remove all acetone and density separation organic solvents residues on the surface of fine coal reject samples. Finally, the density separation solvents-free density separated samples were subjected to the pyrolysis experiments and analyses.
Mineralogy of beach sand in Jumundo, Korea and recovery of heavy minerals using Humphreys spiral concentrator and shaking table followed by magnetic separation process
Published in Geosystem Engineering, 2022
Hee-Young Shin, Soo-Chun Chae, Kyoungkeun Yoo
High-density accessory mineral constituents of siliciclastic sediments are called heavy minerals. In their parent rocks, they are present either as essential rock-forming minerals, for example, amphiboles, pyroxenes, micas, or are accessory components, such as zircon, apatite, tourmaline, etc., occurring in a wide variety of rock types. Heavy mineral grains are seldom encountered in appreciable quantities in the thin sections of sandstone; their total quantity rarely makes up more than 1% of the rock. In order to study heavy minerals effectively, they need to be concentrated, and this is normally done by means of rock disaggregation and mineral separation, using a liquid with a density of 2.89 (bromoform) or 2.96 (tetrabromoethane; Mange & Maurer).
Dense medium separator performance evaluation based on 3D Eulerian-Eulerian multiphase CFD simulation
Published in International Journal of Coal Preparation and Utilization, 2023
Dejalin Sahu, Suresh Nikkam, Hari Vuthaluru, Gordon D Ingram, Omid Kavianipour
The washability analysis of the feed coal was determined by carrying sink-float analysis using mixtures such as organic liquids of bromoform (sp. gr. 2800 kg/m3), tetrabromoethane (sp. gr.1610 kg/m3), and kerosene (sp. gr. 850 kg/m3). The results of the sink-float analysis are plotted in Fig. 1. From Fig. 1, it can be seen that for production of clean coal of 18.0% ash, the coal has to be washed at a density of 1.59 g/cc, which will give a yield of cleans of about 76.0%.