Profile ethylene concentration

Concentration changes observed between mother liquor in the flash zone and liquid product in the melt zone of an experimental triple-point crystallizer have been dramatic. A qualitative concentration profile typical of those observed in the experimental unit is shown in Figure 8. The mother liquor concentration is relatively uniform above the packed bed, but a sharp drop in contaminant concentration occurs within the top several inches of the loosely packed crystal bed. Concentration changes of the order 500 to 5000 have been observed for representative sulfurous compounds and trace contaminants, including hydrogen sulfide, carbonyl sulfide, methyl mercaptan, ethane, and ethylene. Concentration profiles calculated for the packed bed of solid carbon dioxide using a conventional packed bed axial dispersion model agree very well with the observed experimental profiles. 

Once the polymerization reaction has developed, a decay in activity can also sometimes be observed because of a chemical instability of the active species. Thus, the kinetic profile of the polymerization reaction can be defined as a series of three consecutive reactions il) reduction, (2) alkylation, and (3) decay. Each step in the series has its own dependency on ethylene concentration, temperature, and catalyst composition. Figure 2 shows some t5 ical kinetic profiles that are often obtained and that can be produced by varying the individual rate constants of the three steps (41). 

Step response experiments for this catalyst show that when the reactor is subjected to a step increase in feed hydrogen, the ethylene concentration profile exhibits damped oscillations, while ethane and acetylene show an overshoot and an undershoot, respectively, followed by a slow monotonic approach to the final steady-state value. On the other hand, an asymmetric response was again observed for a step decrease in feed hydrogen (Figure 6). 

Ethylene oxidation was studied on 8 mm diameter catalyst pellets. The adiabatic temperature rise was limited to 667 K by the oxygen concentration of the feed. With the inlet temperature at 521 K in SS and the feed at po2, o=T238 atm, the discharge temperature was 559 K, and exit Po =1.187 atm. The observed temperature profiles are shown on Figure 7.4.4 at various time intervals. The 61 cm long section was filled with catalyst. 

The calculated thermodynamic parameters in Table X are for 150 °C, a value close to typical operating temperatures, and without pressure corrections, there is no H2 and both alkane and alkene could be at unit concentration. The bottom part of the table is the same as Table VI. The free-energy profile of the transfer reaction mechanism is shown in Fig. 4. In the first step of the mechanism (IVR), sacrificial alkene (in this case ethylene) was bound to the (L)Ir(H)2 complex 4 to form an olefin complex 7. As mentioned above, the forward reaction of this step has no... 

Concentration profiles for compound 67 are given in Figure 7. Although the relative effect of dispersion due to tidal flow and downstream movement due to the net river flow are not precisely known, it is clear from these data that compound 67 comes from a point source located near river mile 100. In fact, the company which produces the precursor alcohols (no. 68-70), the chemically related chlorinated ethylene glycol (no. 64) and the Cg-phenol (no. 38) discharges its effluent at river mile 104. 

Additional experimental data not presented here are summarized in Refs. [66, 67]. As was pointed out also in Ref. [64], these results highlight the important point that in membrane reactors, besides differences in local concentration profiles, different residence time distributions occur that lead to specific reactor behavior. Others [71] have also suggested that the flexibility of this type of distributor membrane reactors allows a certain target component to be produced efficiently within a complex reaction network. In the present example, there exist certain operating conditions under which the membrane reactor outperforms the conventional reactor in terms of the production of CO or CO2 (if these are considered as target products instead of ethylene). 

Concentration profile of nitroxyl radicals resulted from thermo-oxidative destruction of other polymer - ethylene copolymer with propylene is presented in Figure 9b. In this case maximum concentration of nitroxyl radicals is observed not on the borders but in the center of sample the process of thermo-oxidative destruction proceeds mainly in sample depth [49],... 

Use the modeling Eqs. (9.69) and (9.70) with the parameters in Table 9.1 to describe the coupled heat and mass flows by plotting coupled concentration and temperature profiles in oxidation of ethylene to ethlylene oxide. Assume the values e = 0.001 and w = 0.001. 

SAFETY PROFILE Poison by ingestion and intraperitoneal routes. Narcotic in high concentration. Mutation data reported. See also CHLOROFORM. Incompatible with ethylene. When heated to decomposition it emits very toxic fumes of CT and Br". 

Later, Furusaki et al. (F17) studied the hydrogenation of ethylene by fluidized Ni catalyst to obtain the axial reactivity distribution. Here the samples of bed gas were removed by a traveling sampler placed at the center of the bed during steady reaction, so that the sample taken in the dense phase shows an average of the concentration in the bubble and emulsion phase. Figure 74 shows an example of the axial concentration profile. 

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