Extraction of oil

Other than fuel, the largest volume appHcation for hexane is in extraction of oil from seeds, eg, soybeans, cottonseed, safflower seed, peanuts, rapeseed, etc. Hexane has been found ideal for these appHcations because of its high solvency for oil, low boiling point, and low cost. Its narrow boiling range minimises losses, and its low benzene content minimises toxicity. These same properties also make hexane a desirable solvent and reaction medium in the manufacture of polyolefins, synthetic mbbers, and some pharmaceuticals. The solvent serves as catalyst carrier and, in some systems, assists in molecular weight regulation by precipitation of the polymer as it reaches a certain molecular size. However, most solution polymerization processes are fairly old it is likely that those processes will be replaced by more efficient nonsolvent processes in time. 

Casein is the only protein that has achieved commercial significance as a plastics raw material. Many other proteins are readily available in many vegetable material residues which arise from such processes as the extraction of oils and starches from seeds. It would be advantageous to countries possessing such residues if plastics could be successfully exploited commercially. Although plastics materials have been produced they have failed to be of value since they are invariably dark in colour and still have the water susceptibility and long curing times, both of which are severe limitations of casein. 

Polyterpenes. Polyterpenes is one of the first classes of non-polar tack-ifiers to be developed. Terpene monomers are a by-product in the extraction of rosin from wood stumps or tree sap, and from the extraction of oils from citrus fruits. The latter is the dominant source. As such, polyterpene prices generally mirror those of citrus fruits, which fluctuate substantially from one growing season to the next. Terpenes like rosin are cyclic, see Fig. 6, which is partly responsible for their excellent solvent properties. 

All fossil fuels are considered unsustainable because someday they will reach a point of depletion when it becomes uneconomic to produce. Petroleum is the least sustainable because it is the most finite fossil fuel. Although levels of production are expected to begin declining no later than 2030 (U.S. production peaked in 1970), the U.S. and world resei ves could be further expanded by technological advances that continue to improve discoveiy rates and individual well productivity. The extraction of oils found in shales (exceeds three trillion barrels of oil equivalent worldwide) and sands (resei ves of at least two trillion barrels worldwide) could also significantly increase reserves. The reserves of natural gas are comparable to that of oil, but natural gas is considered a more sustainable resource since consumption rates are lower and it burns cleaner than petroleum products (more environmentally sustainable). 

R. N. Diyashev, F. M. Sattarova, K. G. Mazitov, V. M. Khusainov, F. N. Mannanov, I. R. Diyashev, and V. A. Burtov. Extraction of oil from lens-shaped deposits—involves cyclic and portion-wise pumping-in of solutions of potassium carbonate and inhibited hydrochloric acid. Patent RU 2065942-C, 1996. 

Mazzario, Andrea. Process for the extraction of oil of iron. Essentia 4, no. 1 (Spring 1983). r http //homepages.ihug.com.aU/ panopus/essentia/essentiaivl.htm ironl. 

EPA. 1993. Report to Congress on hydrogen sulfide air emissions associated with the extraction of oil and natural gas. Research Triangle Park, NC U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards. EPA/453/R-93-045. NTIS publication no. PB94-131224. 

It is difficult, at present, to get a clear idea of the efficiency of the various plant PHA extraction protocols. In a patent application by Metabolix [74], it was reported that the efficiency of purifying poly(3HB) which was mixed with ground rapeseed was approximately 24% when using an oil-extraction step with hexane followed by refluxing in chloroform for 22 h and evaporating the chloroform to recover poly(3HB). The co-extraction of oil with a PHA contain-... 

In the first experiment the contaminated extracts were obtained and then they were thermally treated by plasma. The analytical results showed that the best solvents for extraction of oil - PCB s were isooctane, cyclohexane, isopropyl alcohol and their mixture. We have found the average extraction efficiency 95%. The best result 96.2% of the extraction efficiency we obtained for the mixture of isooctane and isopropyl alcohol in the ratio 1 1. 

The ultraviolet absorption spectra of extracts of oil-contaminated sediment samples and unpolluted beach are shown in Fig. 2.3. Levy [41]... 

In some cases the soluble material is distributed in small isolated pockets in a material which is impermeable to the solvent such as gold dispersed in rock, for example. In such cases the material is crushed so that all the soluble material is exposed to the solvent. If the solid has a cellular structure, the extraction rate will generally be comparatively low because the cell walls provide an additional resistance. In the extraction of sugar from beet, the cell walls perform the important function of impeding the extraction of undesirable constituents of relatively high molecular weight, and the beet should therefore be prepared in long strips so that a relatively small proportion of the cells is ruptured. In the extraction of oil from seeds, the solute is itself liquid. 

Figure 10.1. Batch plant for extraction of oil from seeds...

There have been a number of reports of the use of enzymes in the extraction of oils from sources such as fish, rape seed, yeast, palms, and soya beans. Celluloses and pectinases are used in pdm oil extraction. In soya bean and fish, much oil has been found to be associated with protein, so that addition of proteases increases the yield of oil and protein. Use of thermostable proteases is preferred, but m general the use of enzymes is limited by the minimal water contents of the various process streams. Trichoderma uride and A niger celluloses, hemicellulases and proteases have been used to extract hydrocarbons from Euphorbia plants 39 40) and similar enzymes used to extract sapogenins from Helleborus 41). 

A paper contributed by J. E. Desnoyers, R. Beaudoin, C. Roux, and C. Perron described the use of microemulsions as a possible tool for the extraction of oil from tar sands. Using a technique called flow microcalorimetry recently developed at the University of Sherbrooke, these researchers studied the structure and stability of organic microphases in aqueous media. These microphases can be stabilized by surfactants and can dissolve large quantities of oil. In a similar vein, D. F. Gerson, J. E. Zajic, and M. D. Ouchi (University of Western Ontario) described the extraction of bitumen from Athabasca tar sands by a combined solvent-aqueous-surfactant system. 

Oil s main disadvantage is its effect on the surrounding air, land, water, and wildlife. The extraction of oil from the land and the sea can be messy. On land, large, invasive oil drills can disturb local wildlife and destroy landscapes. Oil from broken pipelines sometimes pollutes the land. Much oil drilling takes place in the oceans, where oil spills and leaks can harm or kill ocean life. The process of extracting oil has prompted many political and environmental arguments. 

The extraction of oil from mined shale by retorting is an established technology. The major above ground retorting processes have been under development intermittently for over 50 years. A variety of processes are presently candidates for full scale commercialization. 

NGc are completely sol. For their identification, weigh 5.0 g of the filtered expl oil into a large test tube, add 50mi of 60% AcOH, stopper and shake well. Insol oily drops collecting on the bottom of the test tub° indiestbs rsscncs of nitrated polymers. In this case, decant the liquid and repeat the extraction of oil with two addnl 50-ml portions of AcOH. Wash the residue with two 50-ml portions of distd water and separate by decantation. Dissolve the residue in 30 ml of ether and add an excess of anhyd... 

Tetrachloroethane is used as a solvent, for cleansing and degreasing metals, in paint removers, varnishes, lacquers, photographic film, resins and waxes, extraction of oils and fats, as an alcohol denaturant, in organic synthesis, in insecticides, as a weedkiller and fumigant and as an intennediate in the manufacture of other chlorinated hydrocarbons (Lewis, 1993). 

The supercritical fluid extraction of oil seeds has been investigated extensively by several authors [34,98]. Possible applications of supercritical fluids in the edible-oil industry include deacidification, deodorization, and fractionation of crude oils and chemical conversion (like hydrogenation, and enzymatic reactions). 

NOTE Solutions and extracts of oil or lipid samples should be protected from undue exposure to light and air before use in order to prevent deterioration of the existing carbonyl compounds as well as further oxidation of the lipid. 

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