Thermodynamics Of CO. 2 Resource CO2

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4.2 Resources CO2
Fig.1 depicts the principle of chemical energy transmission system.
Fig.2 explain the Eva-Adam process.

5. Thermodynamics of CO2 reforming of methane It is essential to understand the thermodynamic of CDRM represents as follow:
CH_4+CO_2 □(→) 2CO+〖2H〗_2 ∆H_298=247 KJ⁄(mol ) (1)
∆G^o=61770-67.32 T
This reaction above is highly endothermic which is favored by low pressure but, requires a higher temperature. A reverse water-gas shift reaction occurs as a side reaction as below
CO_2+H_2 □(→) CO+H_2 O ∆H_298=41 KJ⁄(mol ) (2)
∆G^o=-8545+7.84 T
Under conditions of stoichiometric CO2 reforming, carbon deposition
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Metal activity
Table 2 illustrates some experimental results that related to reforming methane with CO2 over group VIII metals.[13]

Table 3 showed the synergetic influence for the metals over various supports and reflected on catalytic activity. Order

Figure9: depicts influence noble metal on catalytic activity. At low ratio CO2/CH4 and 1.5% Rh/La2O3 the conversions for CO2 and CH4 were similar but, when feed ratio increased at the 1.5% Rh/La2O3 catalyst demonstrated the higher conversion for both reactants.[14]

Figure10: shows affect the various amount of Ni over NaY, the results showed that the maximum conversion of CO2 and CH4 at 3.3 wt % Ni loading. One other hand, the formation rate of H2 and CO decreased sharply as the amount of Ni exceeded more than 2 wt %.[15]

6.2.3. Effect of support on catalyst activity
Figure11: illustrates the effect of Al2O3, TiO2, and MgO as a promoter on the catalytic activity of Rh/SiO2 catalysts that were physically mixed. It was noted the synergetic effect promoted
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It is found that the influence of support (metal oxides) on the efficiency of the catalyst as order TiO2 > Al2O3 > SiO2 for coupling CO2 with the CH4 conversion. On the other hand, the turnover frequency for CH4 conversion, the order of performance was TiO2 > Al2O3 > SiO2. It was deduced that the synergetic effect of metal oxides might be due to a direct activation of CH4 or CO2 by metal oxides and the difference of particle size of the metal.[16]

6.2.4. Carbon formation and activity
Deposition of carbon is assigned to from the CO2 molecular route, but a minimal amount of carbon deposited on catalyst surface is derived from the CH4 molecular direction.56,60 There are types of carbonaceous in which has different reactivity (α-C,β-C, and γ-C).
NO. Name of author Journal, volume, year Briefly about his work
1 Zhang and Verykios[17]
J. Chem. Soc., Chem. Commun. 1995, It is studied effect found that carbon is originating from the CH4/CO2 over Ni/La2O3 catalyst. It is demonstrated that promoting the reaction via its interaction with a component migrated from the La2O3

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