Solvent extraction worldwide production

Economic considerations in the 1990s favor recovering butadiene from by-products in the manufacture of ethylene. Butadiene is a by-product in the C4 streams from the cracking process. Depending on the feedstocks used in the production of ethylene, the yield of butadiene varies. Eor use in polymerization, the butadiene must be purified to 994-%. Cmde butadiene is separated from C and C components by distillation. Separation of butadiene from other C constituents is accomplished by salt complexing/solvent extraction. Among the solvents used commercially are acetonitrile, dimethyl acetamide, dimethylform amide, and /V-methylpyrrolidinone (13). Based on the available cmde C streams, the worldwide forecasted production is as follows 1995, 6,712,000 1996, 6,939,000 1997, 7,166,000 and 1998, 7,483,000 metric tons (14). As of January 1996, the 1995 actual total was 6,637,000 t. 

The solvent extraction process that uses TBP solutions to recover plutonium and uranium from irradiated nuclear fuels is called Purex (plutonium uranium extraction). The Purex process provides recovery of more than 99% of both uranium and plutonium with excellent decontamination of both elements from fission products. The Purex process is used worldwide to reprocess spent reactor fuel. During the last several decades, many variations of the Purex process have been developed and demonstrated on a plant scale. 

For extractive distillation, extraction and absorption processes, highly selective solvents are required. The economic importance of extraction and extractive distillation processes can be recognized from the fact that the worldwide production of the BTX aromatics (benzene, toluene, xylenes, ethylbenzene) as important primary petrochemical products for the industrial manufacturing of many chemical products... 

Dimethylformamide (DMF) has been known since 1893, but since the 1950s, it has evolved as an important solvent. Its main uses are as a solvent for spinning acrylic fibers, polyurethane and polyamide coatings and films, PVC, polyacrylonitrile, extraction of aromatics from petroleum, selective solvent for removal of acid gases from natural gas, solvent for dyes, electrolyses in galvanization processes, and paint remover and cleaner [16]. By 1980, the worldwide production of DMF had grown equal to the production of formic acid at 220,000 metric tons per year [18]. By 1993 the U.S. production of formic acid was 30 to 35 mm pounds and DMF production had grown to 60 to 65 mm pounds. 

Production By steam distillation of the dried (fermented) leaves of the patchouli shrub, Pogostemon cablin, syn. P. patchouli (Lamiaceae), growing mainly in Indonesia but also in China, Brazil, and Russia. Solvent extraction of patchouli leaves furnishes the valuable patchouli resin. The annual production worldwide probably amounts to 8001. 

Aromatic Hydrocarbons. Sulfolane is used principally as a solvent for extraction of benzene, toluene, and xylene from mixtures containing aHphatic hydrocarbons (33—37). The sulfolane process was introduced in 1959 by SheU Development Company, and that process is Hcensed by Universal OH Products. A sulfolane extraction process is also Hcensed by the Atlantic Richfield Company. In 1994, worldwide consumption was estimated at ca 6974 t/yr of sulfolane for 137 sulfolane extraction units (see Bix processes Extraction, liquid-liquid Xylenes and ethylbenzene). 

A higher proportion of sclareol is present in the clary sage concrde, which is obtained by extraction of the blooming plants with hexane its content may amount to around 70 %. After counter-extraction with 87 % methanol and evaporation of the solvent, a syrupy residue remains, which crystallises and has a sdareol content of over 90%. [216, 217] The worldwide annual production is estimated at 50-150 tonnes. [218]... 

Petroleum extraction and processing is the human exploitation of fossil fuels consisting of hydrocarbons in the form of crude oil and natural gas. The primary use of processed petroleum products is as powerful fuels, particularly for transportation in the form of gasoline, diesel fuel, or jet fuel, and for heating purposes, which account for 84 percent of petroleum use. The remainder of processed petroleum products is used in the petrochemical industry as fuel additives and to create applications such as plastics, specialty chemicals, solvents, fertilizer, pesticides, and pharmaceuticals. Worldwide, about 37 billion barrels of crude oil and natural gas are extracted each year. 

Sulfolane, another highly polar solvent, is used to separate aromatic hydrocarbons from aliphatic hydrocarbons [10]. The extraction process first developed by Shell Oil in 1959 and which is referred to as the Sulfolane process is used worldwide. The solvency of sulfolane for certain fatty acids and fatty acid esters is the basis for upgrading animal and vegetable fatty acids used in food products, paints, plastics, resins, and soaps. Aqueous solutions containing 30-70 wt% sulfolane are used to remove lignin from wood chips [11]. Sulfolane is used to remove acidic components like hydrogen sulfide and carbon dioxide from gas feed stocks. 

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