https://doi.org/10.1016/j.fuel.2022.123420
“The ICCM performances of Ru/CeO2-MgO combined materials with different CeO2 morphologies were carried out in a fixed bed reactor with a stainless-steel tube (8 mm in diameter) at atmospheric pressure. Typically, 0.3 g combined materials was placed in the middle of the reaction tube and fixed by quartz wool, and two thermocouples were used to control the temperature of the combined materials and the furnace, respectively. Omega mass flow meter controllers (FMA-A2306) were calibrated by a bubble flowmeter and used to control the gas flow. ICCM includes two stages: carbonation reaction (1st stage) and CO2 methanation (2nd stage). The 1st stage was performed using 35% CO2/N2 at 100 ml/min at 300 °C for 1 h, followed by sample purge in 50 ml min−1 N2 for 10 min. Then, 5% H2/N2 at a 50 ml min−1 flow rate was switched on for the 2nd stage for 30 min isothermally. The exhaust gases coming out of the 2nd stage reactor were collected by a gasbag and analyzed by a GC (HP Hewlett 5890 series Ⅱ gas chromatograph) with a Restek Shincarbon ST 100/120 column (2 m, 1 mm ID/1/16′’ OD Silco). The cycle evaluation was performed with extra 20 mins N2 purge among each cycle. The yields of CH4, CO2, and CO2 conversion were calculated using the below equations (No CO and other hydrocarbons were detected):
(2)YCH4=Vgas∗FCH422.4∗mDFM
(3)YCO2=Vgas∗FCO222.4∗mDFM
(4)CCO2=YCH4(YCO2+YCH4)∗%
YCH4 (mmol g−1), YCO2 (mmol g−1) and CCO2 (%) represent CH4 yield (mmol CH4 per gram of combined materials), CO2 yield (mmol CO2 per gram of combined materials) and CO2 conversion, respectively. Vgas and F are the produced gas volume of exhaust gas (ml) and gas fraction (%) determined from GC, respectively.”