Calcium promoted Fe/Al2O3 oxygen carrier for hydrogen production via cyclic chemical looping steam methane reforming process

Hafizi, Ali; Rahimpour, Mohammad Reza; Hassanajili, Shadi

doi:10.1016/j.ijhydene.2015.10.021

Cited by 59 publications

(23 citation statements)

References 34 publications

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“…Specific surface area and pore volume of both samples were decreased significantly due to sintering and blocking the pores during CL-SMR process at high temperature of 650 °C. In addition, coke formation on the surface of oxygen carrier in reduction section can effectively decrease the specific surface area of samples [1]. It is noteworthy that the presence of yttrium on the surface of support leads to lower reduction in pore volume and specific surface area of 25Ni-2.5Y/SBA-16 compared to 25Ni/SBA-16 OC.…”

Section: Life Time Of 25ni/sba-16 and 25ni-25y/sba-16 Oxygen Carriersmentioning

confidence: 96%

“…Fast depletion of conventional fossil fuel sources and increasing concerns over the global warming phenomenon due to the emissions of greenhouse gases especially carbon dioxide, initiated various researchers for the production of clean energies [1][2][3][4][5][6]. H 2 has been widely identified as a favorable clean energy carrier because of its non-polluting nature and high specific energy density (120.7 kJ/g) [7][8][9].…”

Section: Introductionmentioning

confidence: 99%

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Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

et al. 2017

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Abstract:In this work, the modification of Ni/SBA-16 oxygen carrier (OC) with yttrium promoter is investigated. The yttrium promoted Ni-based oxygen carrier was synthesized via co-impregnation method and applied in chemical looping steam methane reforming (CL-SMR) process, which is used for the production of clean energy carrier. The reaction temperature (500-750 • C), Y loading (2.5-7.4 wt. %), steam/carbon molar ratio (1-5), Ni loading (10-30 wt. %) and life time of OCs over 16 cycles at 650 • C were studied to investigate and optimize the structure of OC and process temperature with maximizing average methane conversion and hydrogen production yield. The synthesized OCs were characterized by multiples techniques. The results of X-ray powder diffraction (XRD) and energy dispersive X-ray spectroscopy (EDX) of reacted OCs showed that the presence of Y particles on the surface of OCs reduces the coke formation. The smaller NiO species were found for the yttrium promoted OC and therefore the distribution of Ni particles was improved. The reduction-oxidation (redox) results revealed that 25Ni-2.5Y/SBA-16 OC has the highest catalytic activity of about 99.83% average CH 4 conversion and 85.34% H 2 production yield at reduction temperature of 650 • C with the steam to carbon molar ratio of 2.

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Section: Life Time Of 25ni/sba-16 and 25ni-25y/sba-16 Oxygen Carriersmentioning

confidence: 96%

Section: Introductionmentioning

confidence: 99%

Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

et al. 2017

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“…Actually, carbon deposited on the Oxygen carrier's surface and reduced specific surface area in reduction step. Furthermore, pore blockage and sintering of OC occurred at 700 • C [10]. The energy dispersive X-ray (EDX) carbon result of 15Ni/Ce-SBA-16(40) and 15Ni/Ce-SBA-16(∞) OCs after 16 redox cycles at 700 • C is presented in Table 3.…”

Section: Time-on-stream Behavior Of Oxygen Carriermentioning

confidence: 99%

“…In this process, the oxygen source could be supplied from either air or pure oxygen. In the first oxygen source, the product is diluted with nitrogen, whereas in the second one, an oxygen plant is required [10,11]. In order to reduce the cost of reforming, chemical looping reforming (CLR) process was suggested by Mattisson and Lyngfelt [12].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and Application of Cerium-Incorporated SBA-16 Supported Ni-Based Oxygen Carrier in Cyclic Chemical Looping Steam Methane Reforming

et al. 2018

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Hydrogen, as a clean energy carrier, could be produced aided by cyclic oxidation-reduction of oxygen carriers (OCs) in contact with carbonaceous fuel in chemical looping steam methane reforming (CL-SMR) process. In this study, the cerium was incorporated into the SBA-16 support structure to synthesize the Ni/Ce-SBA-16 OC. The supports were synthesized using hydrothermal method followed by impregnation of Ni and characterized via low and wide angle X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), scanning electron microscopy (SEM), coupled with energy dispersive X-ray (EDX) spectroscopy, and transmission electron micrograph (TEM) techniques. In addition, the effect of various Si/Ce molar ratios (20-60) in the support structure, Ni loading (10-30 wt %), reaction temperature (500-750 • C), and life time of optimal oxygen carrier over 16 cycles were investigated. The results of wide angle XRD and SEM revealed that the incorporation of CeO 2 in the channels of SBA-16 caused the formation of nickel metallic particles with smaller size and prevents the coke formation. The results showed that OC with 15 wt % Ni and Si/Ce molar ratio of 40 (15Ni/Ce-SBA-16(40)) has the best performance when compared with other OCs in terms of catalytic activity and structural properties. The methane conversion of about 99.7% was achieved at 700 • C using 15Ni/Ce-SBA-16(40) OC. We anticipate that the strategy can be extended to investigate a variety of novel modified mesoporous silica as the supporting material for the Ni based OCs.

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“…In addition, in partial oxidation of methane, the O 2 comes from either air or pure oxygen [24]. Using air as oxygen source has the disadvantage of N 2 impurity and NO X in its syngas, while a costly oxygen plant is required in the second one [25].…”

Section: Introductionmentioning

confidence: 99%

Promotion of Ca-Co Bifunctional Catalyst/Sorbent with Yttrium for Hydrogen Production in Modified Chemical Looping Steam Methane Reforming Process

et al. 2017

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Abstract:In this study, the application of a calcium-based bifunctional catalyst/sorbent is investigated in modified chemical looping steam methane reforming (CLSMR) process for in situ CO 2 sorption and H 2 production. The yttrium promoted Ca-Co samples were synthesized and applied as bifunctional catalysts/sorbent. The influence of reduction temperature (500-750 • C), Ca/Co and Ca/Y ratios (1.5-∞ and 3-18, respectively) and catalyst life time are determined in CLSMR process. The physicochemical transformation of fresh, used and regenerated samples after 16 redox cycles are determined using X-ray powder diffraction (XRD), N 2 adsorption-desorption, field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM) techniques. The effect of yttrium promoter on the structure of catalyst and regeneration step on the reversibility of bifunctional catalyst/sorbent was two important factors. The characterization results revealed that the presence of yttrium in the structure of Ca-9Co sample could improve the morphology and textural properties of catalyst/sorbents. The suitable reversibility of bifunctional catalyst/sorbents during the repeated cycles is confirmed by characterization of calcined samples. The Ca-9Co-4.5Y as optimal catalyst illustrated superior performance and stability. It showed about 95.8% methane conversion and 82.9% hydrogen yield at 700 • C and stable activity during 16 redox cycles.

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Calcium promoted Fe/Al2O3 oxygen carrier for hydrogen production via cyclic chemical looping steam methane reforming process

Cited by 59 publications

References 34 publications

Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

Synthesis and Application of Cerium-Incorporated SBA-16 Supported Ni-Based Oxygen Carrier in Cyclic Chemical Looping Steam Methane Reforming

Promotion of Ca-Co Bifunctional Catalyst/Sorbent with Yttrium for Hydrogen Production in Modified Chemical Looping Steam Methane Reforming Process

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