Energy efficient methane-to-syngas conversion with low H2/CO ratio by simultaneous catalytic reactions of methane with carbon dioxide and oxygen

Modeling and optimization of the combined carbon dioxide reforming and partial oxidation of natural gas

“…The GHSV was measured at the feed conditions, for pressure of 1 atm and temperature of 25 • C. Reactions were performed at O 2 /CH 4 ratios of 0.25, 0.40 and 0.55 gmol/gmol, GHSV of 10,000, 15,000 and 20,000 h −1 , with temperatures in the range of 600-1100 • C. Reaction conditions were selected in accordance with previous experience [4,11,14,26] and are sufficiently broad to include operation conditions normally used at actual industrial sites. A reactor feed flow rate with CO 2 /CH 4 ratio of 0.37 gmol/gmol was used, in accordance with previous optimization studies [26].…”

“…The synthesis gas production can be made by the combined process of carbon dioxide reforming and partial oxidation of natural gas, described as 2CH 4 + CO 2 + 1 2 O 2 → 3CO + 4H 2 (11) This process can produce low hydrogen/carbon monoxide ratios (near 1), which are appropriate for production of oxygenated compounds, heavy hydrocarbons by Fischer-Tropsch synthesis and carbon monoxide for synthesis of polycarbonates [4,16]. Besides, the combination of these reactions is energetically favorable [12,14,15]. Addition of oxygen feed to the carbon dioxide reforming can reduce the carbon deposition on the catalytic surface and increase the methane conversion, although this can also cause the reduction of process selectivity [4].…”

“…Additionally, as the methane oxidation is highly exothermic, the temperature control of the reactor may be very difficult at certain conditions, leading to the formation of hot spots (huge temperature peaks in the catalyst bed). The addition of carbon dioxide feed to the partial oxidation reaction can significantly improve the reactor temperature control and reduce the risk of hot spot development, as the carbon dioxide reforming of methane is endothermic [14,16]. Experimental design and mathematical modeling techniques are the mathematical tools normally used to optimize a process.…”

06/00044 A novel process for converting coalmine-drained methane gas to syngas over nickel-magnesia solid solution catalysts

“…Although the partial oxidation of methane is mildly exothermic and relatively energy efficient, the process cannot be easily controlled because of the generation of hot spots in the catalyst bed [8]. As an alternative, the coupled exothermic catalytic partial oxidation with endothermic CO 2 reforming has attracted many attentions because it can be conducted in a safe and energy-efficient manner [12][13][14][15][16]. Furthermore, carbon deposition on the catalysts particularly on Nibased catalysts in the CO 2 reforming process can be eliminated or drastically reduced in the coupled process [12].…”

“…As an alternative, the coupled exothermic catalytic partial oxidation with endothermic CO 2 reforming has attracted many attentions because it can be conducted in a safe and energy-efficient manner [12][13][14][15][16]. Furthermore, carbon deposition on the catalysts particularly on Nibased catalysts in the CO 2 reforming process can be eliminated or drastically reduced in the coupled process [12]. Thus, a desirable option in directly utilizing the coalminedrained methane gas is to convert it into synthesis gas through the combined partial oxidation and CO 2 reforming of methane.…”