Methane conversion vs. temperature

Figure 2.22 Effect of reaction temperature on methane conversion vs. temperature at S/C 3.5 and WHSV 6 Ndm3 (min gcat) 1[51] (by courtesy of Elsevier Ltd.).

Figure 1 shows the plots of methane conversion vs. temperature for catalysts supported on alumosilicate ceramics. It is seen that the highest activity in methane oxidation has the sample with the active component 0,4%Pt + 0,2%Pd (T " = 440°C). The lowest activity is exhibited by the sample containing only 0,3%Pt (T ° = 55o"C). 

Figure 1. Methane conversion vs. temperature for catalysts on the base of alumosilicate ceramics.

Fig. 2. Methane conversion vs. temperature for Pt/alumina catalysts prepared by different methods. Feed composition 0.3% CH4, 16% O2, balance He. a) No Cl, b) Cl containing, c) addition of 2% Cl" and calcination at 300°C, d) addition of Cl" in excess and calcination at 300°C, e)addition of 2% Cl", no calcinations.

Figure 14.16 Methane conversion vs temperature over Au/Co504and AU/C03O4-CeOj catalysts in the presence of 10 ppm of SOj in the feed. From Liotta et with permission.

High energy content, low vapor pressure (200 psi), and liquid state at ambient temperatures favors low-cost liquid pipeline transportation vs. high-pressure compressed gas—1000+ psig if methane conversion is done near the production site. 

Figure 3. Experimental and predicted methane conversion rate at three different temperatures vs. carbon dioxide partial pressure (Pcf = 0.2 atm. and Pq2 = 0.01 atm. in the feed).

Pd-based membranes, mainly Pd-Ag (23%wt), have been extensively tested for natural gas steam reforming, which is the main process to produce large amount of hydrogen. Many experimental works are reported in the literature [7-11], attesting the good performance in terms of natural gas conversion at much lower operating temperature than traditional process (methane conversions up to 90-95% at 450-550 vs. 850-1000°C). 

Figs. 1 and 2 show experimental and calculated conversions vs. inlet temperature for different methane inlet molar fractions and inlet flowrates, respectively. Fig. 1 shows that the higher reactant inlet concentration the lower is the outlet conversion. This is the expected... 

Figure 2.19 Conversion and selectivity vs. pressure for partial oxidation of methane at 1200 °C reaction temperature and an O/C ratio of 1 half-filled symbols indicate calculated thermodynamic equilibrium values [44] (by courtesy of ACS).

Fig. 2. Conversion of methane on selected catalysts vs. reaction temperature 100-...

Effect of Temperature. Figure 3 gives data showing the conversion of the carbon in the coal to the hydrocarbon gases methane, acetylene, and ethylene, and to carbon monoxide and carbon dioxide. The conversion data are plotted vs. the measured temperature without regard for variations in the other operating variables. These conversions were computed from the measured volume and composition of the gas produced, after condensation of the water vapor and the feed rate of the coal. 

Figure 14 shows a representative composite plot of the fractional conversion, the methane rate of production, and the temperature vs. 

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