Tar oil

Properties of the tar oil products are given in Table 14. The oils change only slightly with change in the retorting temperature sulfur levels are low. The fraction boiling up to 230°C contains 65 wt % of phenols, cresols, and cresyUc acids. 

TOSCO tar oils have high viscosity and may not be transported by conventional pipelines. Heating values of product gas on a dry, acid gas-free basis are in the natural gas range if butanes and heavier components are included. 

Large-scale recovery of light oil was commercialized in England, Germany, and the United States toward the end of the nineteenth century (151). Industrial coal-tar production dates from the earliest operation of coal-gas faciUties. The principal bulk commodities derived from coal tar are wood-preserving oils, road tars, industrial pitches, and coke. Naphthalene is obtained from tar oils by crystallization, tar acids are derived by extraction of tar oils with caustic, and tar bases by extraction with sulfuric acid. Coal tars generally contain less than 1% benzene and toluene, and may contain up to 1% xylene. The total U.S. production of BTX from coke-oven operations is insignificant compared to petroleum product consumptions. 

Many other compounds are presendy in use a 1993 database search showed 27 active ingredients in 212 products registered by the U.S. EPA for human use as repellents or feeding depressants, including octyl bicycloheptene dicarboxamide (A/-2-ethylhexylbicyclo[2.2.1]-5-hepten-2,3-dicarboxamide), dipropyl isocinchomeronate (2,5-pyridine dicarboxyhc acid, dipropyl ester), dimethyl phthalate, oil of citroneUa, cedarwood oil, pyrethrins, and pine tar oil (2). Repellent—toxicant or biting depressant systems are available which are reasonably comfortable for the user and can protect completely against a number of pests for an extended period of time (2). 

Area repellents are materials that are intended to keep animals away from a broad area. They include predator scent such as Hon or tiger manure, blood meal, tankage such as putrefied slaughterhouse waste, bone tar oil, rags soaked in kerosene or creosote, and human hair (84). Although few controlled tests have been mn on these materials in the past, more recent investigations of predator odors have shown promise (85). 

Timber-preservation creosotes are mainly blends of wash oil, strained anthracene oil, and heavy oil having minor amounts of oils boiling in the 200—250°C range. Coal-tar creosote is also a feedstock for carbon black manufacture (see Carbon, carbon black). Almost any blend of tar oils is suitable for this purpose, but the heavier oils are preferred. Other smaller markets for creosote were for fluxing coal tar, pitch, and bitumen in the manufacture of road binders and for the production of horticultural winter wash oils and disinfectant emulsions. 

Several methods ean be employed to eonvert eoal into liquids, with or without the addition of a solvent or vehiele. Those methods which rely on simple pyrolysis or carbonization produce some liquids, but the mam produet is eoke or char Extraction yields can be dramatically increased by heating the coal over 350°C in heavy solvents sueh as anthraeene or eoal-tar oils, sometimes with applied hydrogen pressure, or the addition of a eatalyst Solvent eomponents whieh are espeeially benefieial to the dissolution and stability of the produets eontain saturated aromatic structures, for example, as found in 1,2,3,4 tctrahydronaphthalene Ilydroaromatie eompounds are known to transfer hydrogen atoms to the coal molecules and, thus, prevent polymerization... 

Aromatic hydrocarbon resins. The polymerization procedure and variables in the reactions of the aromatic hydrocarbon resins are similar to those for the coumarone-indene resins. However, the Cg feedstreams used in the polymerization of the aromatic hydrocarbon resins do not contain significant amounts of phenols or pyridine bases, so they are submitted directly to fractional distillation. Distillation produced more byproducts than light coal-tar oils. The aromatic hydrocarbon resins obtained have softening points between liquid and 125°C and Gardner colour of 6 to 11. By changing distillation conditions, aromatic hydrocarbon resins with softening points between 65 and 170°C and Gardner colour of 5 to 10 can also be obtained. 

Tamiluadu Petroproducts Ltd. (TPL), 176 Tantalum and Tantalum Compomids, 125 Tantalum Mining Coi"p. of Canada Ltd. (Tanco), 150 Tantalum Mining Corporation of Canada Ltd. (Tanco), 221 Taoka Chemical Co. Ltd., 189 Tar oil, 125... 

Figure 1.2 Chromatogram of coal-tar oil obtained by using the following conditions column, Waters Spherisorb PAH 5 mm in 250 p.m id X 30 cm fused silica column oven temperature, 100°C UV detector wavelength to 254 nm mobile phase, 100 to 300 bar CO2 and 0.10 to 1.00 p.L min methanol over 30 minutes.

Birken-holz, n. birch wood, -holzteer, m. birch-(wood) tar. -holzteerseifc, /, birch tar soap, -kampher, m, birch camphor, betulin. -kohle, /, birch charcoal, -rinde, /, birch bark. -liftdaiUil, -61, n. oil of betula, cdl of sweet bircb. -teer, m. tdrch tar. -teerdt, n. birch tar oil. 

Pech-kiefer,/. pitch pine, -kohle,/. pitch coal jet. -koks, m. coke from pitch or tar. -ol, n. tar oil, oil of tar, -pflaster, n. asphalt paving. -riickstand, m. pitch residue, pechschwarz, a. pitch-black. 

Schwel-ofen, m. low-temperature carbonizing furnace, -raum, m. carbonizing space or chamber, -retorte, /. retort for low-temperature distillation, -teer, m. tar from low-temperature carbonization, -teerol, n. carbonization tar oil, esp. from lignite. 

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