Effect of temperature on conversion

Figure 8. Effect of temperature on conversion of untreated and demineralized Liddell coal (300-mL autoclave, 6.9 MPa, 4 hr) (O), untreated (%), demineralized.

Figure 3. Effect of temperature on conversion of molinate to its sulfoxide by carp liver microsomal mfo (liver microsomal protein 6 mg/mL, pH 7.4, NADPH 3 mg incubated for 15 min)...

The effect of temperature on conversion and selectivity for R = 0.9910 and Z = 0.020 is shown in Figure 4. With increase in temperature from 350° to 425°C., although the conversion increased, the selectivity remained nearly constant. 

Figure 2.16 shows the effect of temperature on conversion for different values of ( Eq)333 with reactor volume fixed at 100 m3. 

Figure 3. Effect of temperature on conversion for flow and single-shot reactions...

Effect of Temperature on Conversion of Char Nitrogen to N0X. The ef-fect of oxidation temperature upon the proportional release of N0X is tabulated in Table II for pure acridine and phenanthridine chars at... 

Table II. Effect of Temperature on Conversion of Char Nitrogen to N0X...

Figure 6. Effect of temperature on conversion of 2-MON catalyst Amberlyst-15 (355 pm), catalyst loading 0.4g, speed of agitation 1500 rpm, 2-MON 5g, Ac20 35g...

The effect of contact time on conversion and selectivity are shown in Fig.2. It is observed that the conversion increases with the increase in contact time (W/F). Selectivity to benzaldehyde is also found to increase, it may be fact that with increase in W/F, toluene is oxidised to benzaldehyde. This was ascertained by using toluene as the reactant.The effect of temperature on conversion and selectivity is shown in Fig.3. With increase in temperature conversion is found to increase, selectivity to benzaldehyde decreases while selectivity to toluene increases. 

Figure 3 Effect of temperature on conversion and selectivity in benzyl alcohol oxidation on BaPbo.6Bio.4O3. W/F=51.63 gm.hr/mole, Po2=0 torr. (A% conversion, benzaldehyde, toluene)...

The effect of temperature on conversion and selectivity in benzyl alcohol dehydrogenation in the presence of oxygen is shown in the Fig, 5 The selectivity of benzaldehyde decreases with temperature, whereas that of toluene increases. At high temperatures small amounts of benzoic acid and benzylbenzoate is also observed. The selectivity of which increases with increase in temperature. 

Figure 5 Effect of temperature on conversion and selectivity in ben2yl alcohol oxidation on...

For catalytic combustion, the space velocities range from 10,000 hr to 200,000 h (STP), with larger values for the monoliths with high cell densities. The effects of space velocity and temperature on CO conversion in a medium-density monolith are shown in Figure 10.7. The almost-level plots show that mass transfer is controlling for temperatures above 250°C. Because of the increase in diffusivity with temperature DaT ), there should be some effect of temperature on conversion. Flowever, the superficial velocity is proportional to T for tests at constant SVsxp, and, as shown by Eq. (10.10), the increase in u cancels much of the effect of increased k. For a change in temperature from 300 to 450°C at SV xp = 120,000, the CO conversion should increase by about 2%. 

In order to select the most efficient enzyme for this reaction, two commercial enzymes were screened. Lipozyme and Novozyme were used to study the effect of temperature on conversion soybean oil into fatty amides. The reaction catalyzed by Lipozyme gave the highest percentage of conversion in the reaction temperature range of 30 - 60 °C (Table 1) indicating that Lipozyme was more active for the reaction than Novozyme. Therefore, Lipozyme was used as the lipase in this study. It was also observed that Lipozyme is most efficiently at 40 °C. The percentage of conversion to fatty amides decreases at above 40 °C due to destruction of its catalytic activity by thermal energy [22]. So, a reaction temperature of 40°C was used for further studies. 

Table 1 Effect of temperature on conversion soybean oil into fatty amides by various enzymes (a) Lipozyme and (b) Novozyme. Other reaction conditions Thiourea/palm oil molar ratio = 5.0 1.0, Hexane = 20 ml, Reaction time = 24 h and pH = 7...

Fig. 4. Effect of temperature on conversion of 5-caffeoylquinic acid to methyl caffeate by chlorogenate hydrolase (Kurata et al., 2011). The reaction was performed at 20°C to 60°C for 4 h with immobilized chlorogenate hydrolase and [bmim][NTf2] as the reaction solvent.

Thermal Properties. Before considering conventional thermal properties such as conductivity it is appropriate to consi r briefly the effect of temperature on the mechanical properties of plastics. It was stated earlier that the properties of plastics are markedly temperature dependent. This is as a result of their molecular structure. Consider first an amorphous plastic in which the molecular chains have a random configuration. Inside the material, even though it is not possible to view them, we loiow that the molecules are in a state of continual motion. As the material is heated up the molecules receive more energy and there is an increase in their relative movement. This makes the material more flexible. Conversely if the material is cooled down then molecular mobility decreases and the material becomes stiffer. 

According to Le Chatelier s principle, conversion is increased by increasing the temperature and decreasing the pressure. Figure 6-3 shows the effect of temperature on the dehydrogenation of different light paraffins. ... 

Fig. 1 Effect of temperature on NH3 oxidation. Closed symbols electric finnace, open symbols microwave heating,, O NH3 conversion, A, A N2 selectivity,, NO selectivity, BO N2O selectivity.

Fig. 1. The effects of temperature on the conversions of CO2 and CH4 over Ni-YSZ-Ce02 and Ni-YSZ-MgO catal5rsts.

The effects of temperature on the conversions of CO2 and CH4 and the product distribution over Ni-YSZ-Ce02 catalyst are represented in Fig. 2. The concentrations of H2 and CO were slowly increased with increasing reaction temperature but those of CO2 and CH4 were decreased. Moreover, the concentrations of H2 and CO over Ni-YSZ-Ce02 catalyst were slightly higher than those over Ni-YSZ-MgO [7],... 

Fig.2. Effect of temperature on the conversion and selectivity in a CSTR at SOOpsig.

The choice of reactor temperature depends on many factors. Consider first the effect of temperature on equilibrium conversion. A quantitative relationship can be developed as follows. Start by writing Equation 6.6 at constant pressure ... 

Figure 1 Effect of temperature on catalytic performance of Mg/Al/O catalyst in m-cresol methylation m-cresol conversion (u), selectivity to 3-MA (v), 2,3-DMP (X), 2,5-DMP (ct), 3,4-DMP (p), polyalkylates ( ).

The effect of temperature on the catalytic performance of Mg/Fe/O is reported in Figure 3. The behavior was quite different from that of the Mg/Al/O catalyst. The conversion of m-cresol with Mg/Fe/O was always lower than that with Mg/Al/O. The selectivity to 3-MA was almost negligible in the whole range of temperature. The selectivity to polyalkylates and to 3,4-DMP was also much lower than that observed with Mg/Al/O. Therefore, the catalyst was very selective to the products of ortho-C-methylation, 2,3-DMP and in particular 2,5-DMP. This behavior has to be attributed to specific surface features of Mg/Fe/O catalyst, that favor the ortho-C-methylation with respect to O-methylation. A different behavior of Mg/Al/O and Mg/Fe/O catalysts, having Mg/Me atomic ratio equal to 4, has also been recently reported by other authors for the reaction of phenol and o-cresol methylation [5], The effect was attributed to the different basic strength of catalysts. This explanation does not hold in our case, since a similar distribution of basic strength was obtained for Mg/Al/O and Mg/Fe/O catalysts [4],... 

The aldol condensation reaction of acetone was performed over CsOH/Si02 at a range of reaction temperatures between 373 and 673 K (a typical product distribution is shown in Figure 2). Table 1 displays the conversion of acetone along with the selectivities for the products produced once steady state conditions were achieved. Figure 3 presents the effect of temperature on the yield of the products. The activation energy for acetone conversion was calculated to be 24 kJ. mol 1. 

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