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Paraffinic production

The fifth and final desorbent characteristic is that the desorbent must not react with any feed components that would impart any negative characteristics on either the final extract and raffinate streams. This is important not only for the desired paraffin product purity but also for retaining the desorbent inventory. Therefore, a desorbent s reactivity must be quantified early in the desorbent selection process. [Pg.255]

In 2009 the estimated worldwide detergent range normal paraffin capacity was approximately 3.6 x lO t/year. With more than 27 Ucensed Molex units, liquid-phase adsorption separation is the predominant technology for heavy normal paraffin production. [Pg.262]

Paraffin alkylation involves the add-catalyzed addihon of an olefin to a branched paraffin to give a highly branched, paraffinic product The representahve reaction is that of isobutane with 2-butene to give 2,2,4-trimethylpentane ... [Pg.508]

Uses Solvent standardized hydrocarbon manufacturing paraffin products jet fuel research paper processing industry rubber industry organic synthesis. [Pg.367]

Uses Solvent jet fuel research rubber industry manufacturing paraffin products paper processing industry standardized hydrocarbon distillation chaser gasoline component organic synthesis. [Pg.530]

I. Bake the glass slide with tissue sections approximately 5°C above the melting point temperature of paraffin in the oven for 15 min for improving the tissue section adhesive. The melting point temperature of paraffin depends on the specific paraffin product used. [Pg.344]

Fig. 3. Yields of paraffin products from hexane cracking (H2SM-5, Si/AI = 35, 538°C, 10 torr hexane). Fig. 3. Yields of paraffin products from hexane cracking (H2SM-5, Si/AI = 35, 538°C, 10 torr hexane).
It is necessary, however, to maximize the intermediate olefin product at the expense of the aromatic/paraffin product which makes up the gasoline ( ). The olefin yield increases with increasing temperature and decreasing pressure and contact time. Judicious selection of process conditions result in high olefin selectivity and complete methanol conversion. The detailed effect of temperature, pressure, space velocity and catalyst silica/alumina ratio on conversion and selectivity has been reported earlier ( ). The distribution of products from a typical MTO experiment is compared to MTG in Figure 4. Propylene is the most abundant species produced at MTO conditions and greatly exceeds its equilibrium value as seen in the table below for 482 C. It is apparently the product of autocatalytic reaction (7) between ethylene and methanol (8). [Pg.37]

The desired products are hydrocarbons in the C5 to C10 range that can be used in gasoline production. Iron-, cobalt- and nickel-based catalysts plus the proper selection of reaction temperatures and pressures are used to control product output. Increasing residence time in the reactor yields more paraffinic products and reduces the formation of alcohol and acid. [Pg.275]

With supercritical fluid volatility amplification, a lower temperature can place a satisfactory concentration of the material to be separated into the vapor phase, and since the capacity of molecular sieves increases as the temperature is lowered, a more economical process may be attainable. Higher purity paraffin product may be produced without intermediate washing or purging of the molecular sieves. [Pg.221]

The high pressure (9.06-9.61 MPa) used in Run 6 is probably not necessary for the production of high purity n-paraffinic product. It may be possible to achieve the same results with pressures of 2.6-3.7 MPa. High pressure was also used in Run 8 along with a moderate molecular sieve loading, yet the normals area % was only 58% so it appears that the molecular sieve loading is the important variable. [Pg.240]

A test was made with 2,3-dimethylbutane as the supercritical solvent it has a lower critical temperature than 2,2,4-trimethyl-pentane. Operating at a temperature of 508-512 K, a pressure of 4.10-4.37 MPa, a molecular sieve/oil ratio of 6.39, and a solvent/ oil ratio of 21.3, the molecular sieve capacity attained is 5.73 g/100 g of molecular sieves (as compared to 3.2 g/100 g of molecular sieves with 2,2,4-trimethylpentane at 550 K). The n-paraffin content of the wax distillate was reduced by 88% to a level of 2 wt %, giving a pour point of 266 K. The yield of denormal oil was lower (63%) and the n-paraffin content of the desorbate was lower (44%) at this lower temperature level. This is probably due to increased capillary condensation. Conversely, operation at temperatures greater than 550 K should produce less capillary condensation and purer n-paraffin product. It would be interesting to try supercritical solvents with critical temperatures in the 600-670 K range. [Pg.240]

The recovery of wood resin by naphtha extraction of the resinous portions of dead trees of the resin-bearing varieties or stumps, for example, is also used in the wood industry. The chipped wood is steamed to distill out the resinous products recoverable in this way and then extracted with a naphtha solvent, usually a well-refined, low-sulfur, paraffinic product boiling from, say, 95 to 150°C (200 to 300°F). [Pg.343]

Hydrocarbon distributions in the Fischer-Tropsch (FT) synthesis on Ru, Co, and Fe catalysts often do not obey simple Flory kinetics. Flory plots are curved and the chain growth parameter a increases with increasing carbon number until it reaches an asymptotic value. a-Olefin/n-paraffin ratios on all three types of catalysts decrease asymptotically to zero as carbon number increases. These data are consistent with diffusion-enhanced readsorption of a-olefins within catalyst particles. Diffusion limitations within liquid-filled catalyst particles slow down the removal of a-olefins. This increases the residence time and the fugacity of a-olefins within catalyst pores, enhances their probability of readsorption and chain initiation, and leads to the formation of heavier and more paraffinic products. Structural catalyst properties, such as pellet size, porosity, and site density, and the kinetics of readsorption, chain termination and growth, determine the extent of a-olefin readsorption within catalyst particles and control FT selectivity. [Pg.383]

Recently, a large variety of ion-exchanged zeolites of type X and Y were examined (163) for propylene oligomerization activity. These included LaY, LaX, CeX, MgX, NiY, CoY, A1Y, MgX, MnY, NiX, CoX, and CaX zeolites which were tested in a fixed bed reactor at 190°C. With the exception of NiX, all the zeolites tested showed rather unselective hydrodimerization activity leading to a wide variety of paraffinic products. The appearance of saturated C2, C4, C5, and C7 products was indicative of cracking reactions was well as hydrogen transfer. [Pg.30]

The hydrogen forms of zeolite X and Y are generally more active, but less selective, than their cation-exchanged forms. Side reactions include hydrogen transfer (resulting in the formation of coke and paraffinic products), double-bond migration and disproportionation. [Pg.38]

Application Efficient low-cost recovery and purification processes for the production of LAB-grade and/or high-purity n-paraffin products from kerosine. [Pg.125]

Product quality Typical properties of high-purity n-paraffin product ... [Pg.125]

The recovery process is a vapor phase fixed-bed adsorption technology featuring desorption with ammonia. This process has paraffins recovery and product purity in the high 90% s. Ammonia is a very efficient desorbent. Since it is easily separated from the n-paraffins product, fractionation capital and energy requirements are substantially reduced. Furthermore, ammonia has the added advantage of protecting the adsorbents from coking. [Pg.78]

I n Equal to (0 for pure aromatics. 11 for pure naphthenics or slightly substituted acoinattcs. 12 for mixed hydrocarbons, and 13 for pure paraffinic products. [Pg.173]

Some normal butane is also produced from butylenes but this is estimated at only 4-6%. The higher octane isobutylene alkylate and a claimed yield increase must be contrasted with normal paraffin production from olefins and a higher isobutane requirement. The typical mixed 03 = 704= feed can be made to produce a high octane alkylate with either acid catalyst by the optimization of other variables. The highest alkylate octane numbers reported are produced with sulfuric acid catalyst, alkylating with a typical cat cracker butylene olefin. [Pg.319]

The only unsatisfactory feature of the fit is that the first-order plot of the observed results for pentane dips farther down than that for n-hexanol, the product whose initial rate should be boosted most strongly by the initial abundance of 1-pentene, its only parent (see Fig. 5.9). This behavior is at odds with any fit based on the network 5.43. A better fit would be obtained with a physically impossible negative value of k2S or inclusion of a mechanistically inconceivable direct pathway from 2-pentene to n-hexanol. The most likely explanation of the effect is that mass transfer from the gas phase could not quite keep pace with the extremely high initial rate of consumption of CO and H2 in the liquid, so that the concentrations of these reactants in the liquid decreased temporarily. The effect would be stronger for CO as the larger molecule, and thereby cause a temporary increase in the H2-to-CO ratio in the liquid. A higher ratio favors paraffin production at the expense of the alcohols (see Example 7.5 in Section 7.3.2) and so can explain the observed behavior. (For more detail on mass-transfer effects in this reaction, see Section 12.3). [Pg.103]

Species-specific evolution profiles for the PE-HY sample are shown in Figure 2.5. Unlike the PE-HZSM-5 results, volatile mixtures were primarily composed of C4-C8 paraffin rather than olefin products. Evolution profiles for paraffins and olefins had similar shapes with maximum evolution rates occurring at 230-240°C. Like the paraffin evolution profiles for the PE-HZSM-5 sample, isobutane and isopentane were significant paraffin products and no straight-chain isomers were detected. Alkyl aromatic yields for the PE-HY sample were much lower than for the PE-HZSM-5 sample. [Pg.51]

According to the increase of PS content in HDPE and PS mixture, in Eigure 5.15 the fraction of gasoline components in the liquid products was increased from about 85 wt% (pure HDPE) to about 98 wt% (pure PS) and the rest was kerosene + disel (C13-C24). No heavy oil (> 24) was detected. In the catalytic degradation of pure HDPE without PS, the major product was olefin components whereas the paraffin products as well as the aromatic and naphthene products with a cyclic structure were minor products. According as PS content in the reactant increased from 0 to 20 wt%, the fraction of paraffin... [Pg.150]

As summarized below and described in detail elsewhere (4,5), the olefin readsorption model requires mass conservation equations for growing chains at catalyst sites [Eq. (8)] and for reactive olefins [Eqs. (9) and (10)] and un-reactive paraffin products [Eqs. (11) and (12)] within isothermal spherical pellets. [Pg.234]


See other pages where Paraffinic production is mentioned: [Pg.39]    [Pg.46]    [Pg.120]    [Pg.193]    [Pg.1090]    [Pg.261]    [Pg.272]    [Pg.524]    [Pg.101]    [Pg.124]    [Pg.123]    [Pg.312]    [Pg.227]    [Pg.237]    [Pg.237]    [Pg.241]    [Pg.234]    [Pg.244]    [Pg.125]    [Pg.125]    [Pg.78]    [Pg.51]    [Pg.144]    [Pg.151]    [Pg.182]   
See also in sourсe #XX -- [ Pg.232 ]




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