Paraffin transformations

Overall, this study shows that, like in molecular organometallic chemistry, the chemistry on metal surfaces follows similar elementary steps, and that it is possible to have a molecular understanding of catalytic phenomenon such as paraffin transformations on metal particles. 

A scheme of LPG reactions is proposed in Fig.2 to show the possible low paraffins transformations according to main three routes. It is based on measured products distributions and... 

EPRI Report, 1978, Uniform and non-uniform field electrical breakdown of naphthenic and paraffinic transformer oils, RP 562-1, Contract Nr CCR-78-07 (prepared by the General Electric Co.). 

In 1991, the relatively old and small synthetic fuel production faciHties at Sasol One began a transformation to a higher value chemical production facihty (38). This move came as a result of declining economics for synthetic fuel production from synthesis gas at this location. The new faciHties installed in this conversion will expand production of high value Arge waxes and paraffins to 123,000 t/yr in 1993. Also, a new faciHty for production of 240,00 t/yr of ammonia will be added. The complex will continue to produce ethylene and process feedstock from other Sasol plants to produce alcohols and higher phenols. 

In the propane process, part of the propane diluent is allowed to evaporate by reducing pressure so as to chill the slurry to the desired filtration temperature, and rotary pressure filters are employed. Complex dewaxing requires no refrigeration, but depends on the formation of a soHd urea—/ -paraffin complex which is separated by filtration and then decomposed. This process is used to make low viscosity lubricants which must remain fluid at low temperatures (refrigeration, transformer, and hydraulic oils) (28). 

It should be noted that many practically important catalytic transformations (such as isomerization of or hydrocracking of paraffins), which are presumed to proceed via consecutive mechanisms, are performed on multifunctional catalysts, with which the coupling of reactions in the sense just discussed may not necessarily occur. The problem of the selectivity of some models of polystep reactions on these catalysts has been discussed in detail by Weisz (56). 

In the second process the /z-paraffins are partially chlorinated with chlorine gas in a multistage reactor. The resulting product, a mixture of /z-paraffins and chloroparaffins, is fed, together with excess benzene, into a reactor where AlCl3-catalyzed alkylation is performed. The catalyst suspended or dissolved in the crude alkylate is then separated, while the benzene and unconverted ti-paraffins are recovered by distillation and recycled to the previous reaction stages. In the last step of the process, the LAB is separated from the heavy alkylates. This second process needs to be integrated with a chlorine production unit and with an additional industrial transformation plant which makes use of the corrosive HC1 byproduct. 

Finally, the reaction has also been applied to a wide range of paraffinic materials including polyolefins, which can transformed into lower alkanes... 

There have been no comprehensive studies of how exposure to ethanol, xylene, or paraffin affects proteins following their treatment with aqueous formaldehyde. However, in a related study, Rait et al.25 examined the effect of ethanol incubation on 2 -deoxyadenosine that had been treated with aqueous formaldehyde. Mass spectrometry revealed the presence of N6-ethoxymethyl adducts in addition to hydroxymethyl adducts. This lead to the suggestion that tissue dehydration can result in molecular dehydration, transforming hydroxymethyl groups into Schiff-bases. In such a scheme, the bulk anhydrous ethanol acts as a medium to effectively absorb the water of the... 

No.6 Bunker C No.4 oil Gear oil Turpentine Turpentine Transformer oil Motor oil Lubricating oil Blando oil Hydraulic oil Crude oil Glycol oil Diesel luel Kerosene Chlorinated Paraffin... 

When CH3OH is adsorbed first, the strongly adsorbed CH OH is transformed into ethers, olefins, paraffins and aromatics, m a similar way, when it was the only reactant present (7) (A). C2H4 remains inactive below 623 K. At this temperature, it begins to react as it is shown by the NMR signals in the paraffinic region (B). It can be assumed that in such conditions, ethylene alkylates aromatics obtained from methanol. 

Linear paraffins are key raw materials for the production of LAB as well as for long chain alcohols, which in turn are transformed into a group of... 

Neutral oil products,< -j N-paraffin Spray oils, Transformer oils, Turbine oils, Machine oils, Benzene, Cumene, Gas oils, Linear alkyl benzene. 

In addition to this, solid acid catalysts can also be used in the hydroisomerization cracking of heavy paraffins, or as co-catalysts in Fischer-Tropsch processes. In the first case, it could also be possible to transform inexpensive refinery cuts with a low octane number (heavy paraffins, n-Cg 20) to fuel-grade gasoline (C4-C7) using bifunctional metal/acid catalysts. In the last case, by combining zeolites with platinum-promoted tungstate modified zirconia, hybrid catalysts provide a promising way to obtain clean synthetic liquid fuels from coal or natural gas. 

The dehydroaromatization of light alkane feeds (methane to butanes) into aromatics has come into prominence as a method of converting the unreactive light paraffins into useful chemical precursors. In many of the world s markets, light alkanes are very undesired off-gasses which can not be used other than as fuel. To accomplish this difficult transformation, catalysts typically are bifunctional, containing a dehydrogenating component such as Pt, Ga, Zn or Mo with an acidic zeolite. 

Five key steps for the transformations are indicated by the roman letters. In step I, normal paraffins adsorb on Pt sites and undergo dehydrogenation to form small... 

For positive controls, it is extremely important to have a tissue culture cell line with an abundant amount of target nucleic acid. Varieties of tissue culture cell lines are available from American Tissue Culture Center, Rockville, MD. Rapidly growing tissue culture cell lines transfected with the target nucleic acid could be successfully used for positive controls. For example, formalin-fixed paraffin-embedded foreskin fibroblast tissue culture cell-line FS4 can be used as a positive control for human lysyl oxidase mRNA detection and c-W-ras transformed RS-485 cell line for normal ras message detection. Thin sections (4-5 im) of paraffin-embedded positive control cell lines could be placed simultaneously near the side of the experimental human or animal tissue. Similarly, one can also use freshly cut animal or human tissue (with the target sequences) preserved, sectioned, and mounted under standard laboratory conditions. For negative controls, choose a cell line (or a tissue) that completely lacks the target nucleic acid see Note 12). 

Sample Preparation. The UHMWPE used in this study was a HiFax 1900 (Himont, Inc.) with an average molecular weight of 2-8 x 10. The UHMWPE was added to paraffin oil to concentrations from 2 to 5% w/w. To avoid polymer degradation at high temperatures, the polymer was stabilized with approximately 0.5% of BHT antioxidant. The mixture was stirred at 150 C. A solution was obtained that was clear until it was cooled to about 120 C when it became opaque and transformed into a gel-like or pseudo-gel. 

G.V. Echevsky, E.G. Kodenev, O.V. Kikhtyanin, V.N. Parmon, Direct Insertion of Methane into C3-C4 Paraffins Over Zeolite Catalysts a Start to the Development of New One-Step Catalytic Processes for Gas to Liquid Transformation, 258, Applied Catalysis A General, 159-171, (2004). 

Figure 19 shows the C CP/MAS NMR spectra recorded lOmin to 53 h after adsorption of [ C-l]-l-octene on zeolite HZSM-5. The spectra indicate that the C-labeled terminal olefinic =Cll2 groups evident in the spectra at ca. 113 ppm are transformed into terminal C-labeled paraffinic CH3 groups, evident at 14.3 ppm. Furthermore, the selective label penetrates into internal -CH2- groups of the octene hydrocarbon skeleton, characterized by resonances occurring at 33.0 ppm. 

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