4.2 Explain The Eva-Adam Process

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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Catalysts
6.1. Methods of synthesis catalysts
NO. Name of author Journal, volume, year Name of method Briefly about his work
1 Ashcroft et at.[10]
Science,352, 1991 Vacuum 'incipient wetness' technique It is studied effect vacuum wetness method, and it is demonstrated that highly dispersed noble metal catalysts; thus leads to maintaining the efficiency for CO2 reforming of CH4 with suppressing carbon deposition.
2 Gadalla and Sommer[11]
J. Am. Ceram. Soc., 72, 1984. Coprecipitation
Method They investigated synthesized three catalysts with various compositions (NiO, MgO, and Al2O3).Those demonstrated high CH4 conversion in dry reforming reaction.
3 Chang et al[12]
Stud. Surf. Sci. Catal., 84, 1994. solid-state reaction They researched two methods to prove catalytic activity (solid-state reaction and incipient wetness method) the results show the KNiCa/ZSI catalyst was produced by incipient wetness method gave much less activity than the one prepared by solid-state. That could be melting effect of metallic precursor mixtures.

6.2. Metal activity
Table 2 illustrates some experimental results that related to reforming methane with CO2 over group VIII
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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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