Double sodium salt-promoted mesoporous MgO sorbent with high CO2 sorption capacity at intermediate temperatures under dry and wet conditions

Vu, Anh Tuan; Ho, Keon; Jin, Seongmin; Lee, Chang Ha

doi:10.1016/j.cej.2016.01.080

Cited by 87 publications

(114 citation statements)

References 47 publications

Supporting

Mentioning

103

Contrasting

Order By: Relevance

“…Zhang et al synthesized a composite of MgO and NaNO 3 (80:20 by mass) via ballmilling, with the observation that the CO 2 sorption rate was greatly enhanced, leading to a maximum capacity of 15 mmol•g -1 at 375 °C and 1 bar of CO 2 [18]. A mesoporous MgO prepared using a supercritical drying process was found to be promoted by double sodium salts (NaNO 3 and Na 2 CO 3 ) and exhibited a sorption capacity of 12.7 mmol•g -1 at 325 °C in a dry CO 2 stream and 11.5 mmol•g -1 at 275 °C in a wet CO 2 stream [14]. Use of multiple alkali metal nitrate/nitrite salts further improved both kinetics and capacity of CO 2 sorption for MgO (up to 15.7 mmol•g -1 at 340 °C) [29].…”

Section: ͳǥmentioning

confidence: 98%

“…Additional advantages with MgO include high specific surface area and high pore volume [12][13][14]. The conversion of MgO to MgCO 3 is believed to be limited kinetically, rather than thermodynamically [15,16], and the intrinsically high lattice enthalpy restrains MgO from achieving a fast reaction with CO 2 [17]; moreover, the rigid carbonate "shell" would inhibit CO 2 molecules from accessing more deeply into the MgO structure [18].…”

Section: ͳǥmentioning

confidence: 99%

“…It has been concluded that alkali metal nitrates in molten/pre-molten state can serve as an effective phase transfer catalyst (PTC) promoting the gas-solid reaction between CO 2 and MgO [18]. A sorbent with higher capacity and faster kinetics is still highly probable, since the maximum MgO conversion in the open literature is < 85% [14,16,28,29,31]. Moreover, the role of each promoter in a double/triple promoting system needs to be investigated.…”

Section: ͳǥmentioning

confidence: 99%

“…For example, in the Integrated Gasification Combined Cycle (IGCC) processes, the effluent gas from the shift reactors is at temperature ~ 250-400 °C with CO 2 concentration varying in range of 30-60 mol% [32]. It has been demonstrated that several MgObased sorbents work efficiently in this temperature range [14,16,28,29,31]. However, the study on the effect of lower CO 2 partial pressure and wet conditions is still limited.…”

Section: ͳǥmentioning

confidence: 99%

See 3 more Smart Citations

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Zhao

et al. 2018

Chemical Engineering Journal

103

View full text Add to dashboard Cite

A series of mesoporous MgO samples with different morphologies were synthesized through a simple hydrothermal treatment and NaNO 3 /NaNO 2 were used as promoters to enhance CO 2 capture capacity at an intermediate temperature range (200-400 °C). The effects of hydrothermal solution pH and content of promoters were examined to determine the optimal synthesis conditions. The influence of operational temperatures, CO 2 partial pressure, and performance over repeated cycles was investigated and the reaction mechanism was discussed. The mesoporous MgO promoted by NaNO 3 /NaNO 2 exhibited a CO 2 capture capacity as high as 19.8 mmol•g-1 at 350 °C in the presence of 0.85 bar of CO 2 within only 50 min. A "three-stage" reaction process was proposed based on a detailed sorption kinetics study, namely Stage I: initiating interactions between CO 2 and exposed MgO; Stage II: generation and accumulation of Mg 2+ and CO 3 2-; and Stage III: fast carbonation. Gradual deterioration of sorbents was found over the first 5 cycles followed by stable regenerability in the 5-15 th cycles. A kinetic study of the 15 th cycle suggests that the deactivation of sorbents inhibited the accumulation of Mg 2+ and CO 3 2in Stage II and suppressed the carbonation in Stage III. A range of characterizations were undertaken revealing the morphology and structure of both fresh and regenerated sorbents. The results confirmed that, other than the sintering effect due to phase transition, the transformation of MgO skeleton is also an important contributor to the gradual deactivation of the sorbents over the first 5 cycles. More severe sintering effect under harsh decarbonation conditions suppressed the stability of the sorbents over cycles.

show abstract

Section: ͳǥmentioning

confidence: 98%

Section: ͳǥmentioning

confidence: 99%

Section: ͳǥmentioning

confidence: 99%

Section: ͳǥmentioning

confidence: 99%

See 2 more Smart Citations

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Zhao

et al. 2018

Chemical Engineering Journal

103

View full text Add to dashboard Cite

show abstract

“…Among these, solid adsorbents have been commonly fit for the integrated gasification combined cycles (IGCC) related pre-combustion CO 2 capture processes [4,5], e.g., sorption enhanced water gas shift (SEWGS) and sorption enhanced biomass reforming (SEBR) reactions [12][13][14][15]. Among the abundant solid adsorbents which tend to capture CO 2 at moderate temperatures [5,[14][15][16], layered double hydroxides (LDHs) derived metal oxides [17][18][19][20][21] and magnesium oxide (MgO) based compounds [22][23][24][25][26] are promising for the SEWGS and SEBR technologies in the temperature range of 200-400 • C [10,[27][28][29][30].…”

Section: Introductionmentioning

confidence: 99%

Hydrothermal Fabrication of High Specific Surface Area Mesoporous MgO with Excellent CO2 Adsorption Potential at Intermediate Temperatures

et al. 2017

View full text Add to dashboard Cite

Abstract:In this work, we report on a novel sodium dodecyl sulfate (SDS)-assisted magnesium oxide (MgO)-based porous adsorbent synthesized by hydrothermal method for intermediate CO 2 capture. For industrial MgO, its CO 2 adsorption capacity is normally less than 0.06 mmol g −1 , with a specific surface area as low as 25.1 m 2 g −1 . Herein, leaf-like MgO nanosheets which exhibited a disordered layer structure were fabricated by the introduction of SDS surfactants and the control of other synthesis parameters. This leaf-like MgO adsorbent showed an excellent CO 2 capacity of 0.96 mmol g −1 at moderate temperatures (~300 • C), which is more than ten times higher than that of the commercial light MgO. This novel mesoporous MgO adsorbent also exhibited high stability during multiple CO 2 adsorption/desorption cycles. The excellent CO 2 capturing performance was believed to be related to its high specific surface area of 321.3 m 2 g −1 and abundant surface active adsorption sites. This work suggested a new synthesis scheme for MgO based CO 2 adsorbents at intermediate temperatures, providing a competitive candidate for capturing CO 2 from certain sorption enhanced hydrogen production processes.

show abstract

Unravelling the Mechanism of Intermediate‐Temperature CO₂ Interaction with Molten‐NaNO₃‐Salt‐Promoted MgO

et al. 2021

View full text Add to dashboard Cite

The optimization of MgO‐based adsorbents as advanced CO2‐capture materials is predominantly focused on their molten‐salt modification, for which theoretical and experimental contributions provide great insights for their high CO2‐capture performance. The underlying mechanism of the promotion effect of the molten salt on CO2 capture, however, is a topic of controversy. Herein, advanced experimental characterization techniques, including in situ environmental transmission electron microscopy (eTEM) and CO2 chemisorption by diffuse‐reflectance infrared Fourier transform spectroscopy (DRIFTS), transient 18O‐isotopic exchange, and density functional theory (DFT), are employed to elucidate the mechanism of the CO2 interaction with molten‐salt‐modified MgO in the 250–400 °C range. Herein, eTEM studies using low (2–3 mbar) and high (700 mbar) CO2 pressures illustrate the dynamic evolution of the molten NaNO3 salt promoted and unpromoted MgO carbonation with high magnification (<50 nm). The formation of 18O‐NaNO3 (use of 18O2) and C16O18O following CO2 interaction, verifies the proposed reaction path: conversion of NO3− (NO3− → NO2+ + O2–), adsorption of NO2+ on MgO with significant weakening of CO2 adsorption strength, and formation of [Mg2+… O2−] ion pairs preventing the development of an impermeable MgCO3 shell, which largely increases the rate of bulk MgO carbonation.

show abstract

Double sodium salt-promoted mesoporous MgO sorbent with high CO2 sorption capacity at intermediate temperatures under dry and wet conditions

Cited by 87 publications

References 47 publications

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Hydrothermal Fabrication of High Specific Surface Area Mesoporous MgO with Excellent CO2 Adsorption Potential at Intermediate Temperatures

Unravelling the Mechanism of Intermediate‐Temperature CO₂ Interaction with Molten‐NaNO₃‐Salt‐Promoted MgO

Contact Info

Product

Resources

About

Double sodium salt-promoted mesoporous MgO sorbent with high CO2 sorption capacity at intermediate temperatures under dry and wet conditions

Cited by 87 publications

References 47 publications

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Mesoporous MgO promoted with NaNO3/NaNO2 for rapid and high-capacity CO2 capture at moderate temperatures

Hydrothermal Fabrication of High Specific Surface Area Mesoporous MgO with Excellent CO2 Adsorption Potential at Intermediate Temperatures

Unravelling the Mechanism of Intermediate‐Temperature CO2 Interaction with Molten‐NaNO3‐Salt‐Promoted MgO

Contact Info

Product

Resources

About

Unravelling the Mechanism of Intermediate‐Temperature CO₂ Interaction with Molten‐NaNO₃‐Salt‐Promoted MgO