Study on the redox characteristics of CaCo based oxygen carrier for Chemical Looping Combustion

Son, Eun Nam; Baek, Seung Hun; Lee, Roosse; Baek, Jeom-In; Ryu, Ho Jung; Yoo, Dong Jin; Sohn, Jung Min

doi:10.1016/j.cej.2019.04.102

Cited by 13 publications

(6 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The reason behind this was that the activation energy for reduction was larger than that for oxidation. 55 It may also be that, since the oxidation was exothermic while the reduction was endothermic, local heating during oxidation may have accelerated its reaction as compared to reduction. For the 15NA-ULT OC (see Figure 6), the times required to oxidize and reduce the ULT sample were only 2 and 3 min, respectively.…”

Section: Resultsmentioning

confidence: 99%

“…The curves for the oxidation were also steeper than those of the reduction reaction. The reason behind this was that the activation energy for reduction was larger than that for oxidation . It may also be that, since the oxidation was exothermic while the reduction was endothermic, local heating during oxidation may have accelerated its reaction as compared to reduction.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Ghazali

Aqsha

Komiyama

et al. 2021

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

With the recent advancement of the chemical looping combustion (CLC) industry, the development of materials with high stability, high oxidation and reduction rate, and high oxygen transport capacity (OTC) has become a research hotspot. In this paper, the behavior of nickel oxide (NiO) as an oxygen carrier (OC) has been analyzed using thermogravimetric analysis. The influences of the preparation methods and Ni composition have been evaluated to develop Ni-based carriers with high reduction and oxidation rates over 10 redox cycles without changes in the chemical and structural properties. It has been observed that the carriers prepared by the ultrasound irradiation method showed excellent stability and higher reduction and oxidation rate (less than 1–3 min) during multiple redox cycles. However, their OTC values were lower than those of impregnated carriers. It was found that, in the ultrasound irradiation method, the 15NA (15 wt % Ni loading supported with gamma alumina) OC exhibited the highest OTC (3.17%) while 5NA (5 wt % nickel loading supported with gamma alumina) exhibited the lowest OTC (1.34%). A similar trend was observed for the impregnated OC, where 15NA exhibited the highest OTC value (3.67%), whereas 5NA exhibited the lowest OTC value (1.38%). Overall, the carriers prepared via the impregnation method possessed a high value of OTC at approximately 3.67% while the carriers prepared by ultrasound irradiation possessed an OTC value of 3.17%. In terms of physicochemical properties, the carriers prepared using the ultrasound irradiation approach possessed comparatively lower oxidation and reduction temperatures, smaller particle size, higher specific surface area, and more uniform metal distribution on the support. These findings suggested that the Ni-based OC prepared by ultrasound irradiation is a good candidate for CLC reactions.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Ghazali

Aqsha

Komiyama

et al. 2021

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

show abstract

“…For reduction and oxidation processes, 5% CH 4 /N 2 (for 3 min) and air (for 10 min) were used at a flow rate of 80 mL/min, respectively. However, the temperature of the furnace is kept constant at 800 °C. , Between methane and air, nitrogen gas was purged for 3 min to avoid mixing between methane and air. The OTC of OCs during 10 redox cycles was calculated using eq . OTC = m ox − m red m ox where, m ox is the mass of fully oxidized OC and m red is the mass of fully reduced OC.…”

Section: Methodsmentioning

confidence: 99%

“…However, the temperature of the furnace is kept constant at 800 °C. 14 , 18 Between methane and air, nitrogen gas was purged for 3 min to avoid mixing between methane and air. The OTC of OCs during 10 redox cycles was calculated using eq 1 .…”

Section: Methodsmentioning

confidence: 99%

Investigation on the Redox Properties of a Novel Cu-Based Pr-Modified Oxygen Carrier for Chemical Looping Combustion

et al. 2022

View full text Add to dashboard Cite

CO2 levels in the atmosphere are growing as a result of the burning of fossil fuels to meet energy demands. The introduction of chemical looping combustion (CLC) as an alternative to traditional combustion by transporting oxygen emphasizes the need to develop greener and more economical energy systems. Metal oxide, also defined as an oxygen carrier (OC), transports oxygen from the air to the fuel. Several attempts are being made to develop an OC with a reasonable material cost for superior fuel conversion and high oxygen transport capacity (OTC). This study aims to synthesize a potential OC using the wet impregnation method for the CLC process. Thermogravimetric analysis (TGA) was used to determine the cyclic redox properties using 5% CH4/N2 and air as reducing and oxidizing gases, respectively. The 10CuPA-based OC retained a high OTC of about 0.0267 mg O2/mg of OC for 10 cycles that was higher than 10CuA-based OC. Furthermore, the oxygen transfer rate for 10CuPA-based OC was relatively higher compared to 10CuA-based OC over 10 cycles. In comparison to 10CuA-based OC, the 10CuPA-based OC presented a steady X-ray diffraction (XRD) pattern after 10 redox cycles, implying that the phase was stably restored due to praseodymium-modified γ alumina support.

show abstract

“…3,26 Also as a VIII group element, metallic Co has already been demonstrated active for glycerol steam reforming, 10,20,27 and the chemical-looping hydrogen combustion was realized over Ca 3 Co 2 O 6 . 28 On this basis, we proposed that CCO is a potential OC that can be applied for a CLMC process. and CO 2 in the off-gas were monitored by a GC9790 online gas chromatograph (GC) equipped with a TDX-1 packed column, a methanator, a TCD, and a flame ionization detector.…”

mentioning

confidence: 99%

Pt–calcium cobaltate enables sorption‐enhanced steam reforming of glycerol coupled with chemical‐looping CH₄ combustion

Dang

et al. 2021

AIChE Journal

View full text Add to dashboard Cite

Sorption-enhanced steam reforming (SESR) process is usually highly energy intensive in producing high-purity hydrogen. Herein, the sorbent decarbonation was conducted in the presence of O 2 to enable the exothermic reaction between CaO and CoO x to form calcium cobaltate (CCO). By utilizing CCO as oxygen carrier (OC), the chemicallooping methane combustion was employed prior to the SESR of glycerol (SESRG), by which CCO was prereduced to Co catalysts and CaO sorbent, thereby significantly improving the H 2 yield from SESRG. With a Pt-doped CCO acting as precatalyst, CO 2 sorbent, and OC, we realized 70% CH 4 conversion and 96 vol% H 2 with 120% yield (based on glycerol) for 20 cycles, and the excess H 2 was due to steam gasification of coke. The promoting effects of Pt toward CH 4 conversion and H 2 production were rationalized by CH 4 temperature-programmed reduction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. Our results demonstrate the feasibility of process integration enabled by multifunctional materials.

show abstract

Study on the redox characteristics of CaCo based oxygen carrier for Chemical Looping Combustion

Cited by 13 publications

References 31 publications

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Investigation on the Redox Properties of a Novel Cu-Based Pr-Modified Oxygen Carrier for Chemical Looping Combustion

Pt–calcium cobaltate enables sorption‐enhanced steam reforming of glycerol coupled with chemical‐looping CH₄ combustion

Contact Info

Product

Resources

About

Study on the redox characteristics of CaCo based oxygen carrier for Chemical Looping Combustion

Cited by 13 publications

References 31 publications

Comparative Study on Ni/γ-Al2O3 Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Comparative Study on Ni/γ-Al2O3 Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Investigation on the Redox Properties of a Novel Cu-Based Pr-Modified Oxygen Carrier for Chemical Looping Combustion

Pt–calcium cobaltate enables sorption‐enhanced steam reforming of glycerol coupled with chemical‐looping CH4 combustion

Contact Info

Product

Resources

About

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Comparative Study on Ni/γ-Al₂O₃ Prepared via Ultrasonic Irradiation and Impregnation Approaches as an Oxygen Carrier in Chemical Looping Combustion

Pt–calcium cobaltate enables sorption‐enhanced steam reforming of glycerol coupled with chemical‐looping CH₄ combustion