INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Xia Wan,Xiaojuan Lu,Jie Liu,Yuanfeng Pan,Huining Xiao
CO2 emission has caused serious environmental problems, and the reduction of CO2 has become a global issue. The use of amine-impregnated solid adsorbents for CO2 capture from flue gas has been an effective approach. Herein, a novel porous MgCO3 was synthesized by a facile and template-free method and further impregnated with polyethylenimine (PEI) to prepare porous adsorbent for highly efficient CO2 capture. Moreover, during the synthesis of MgCO3, CO2 was used as one of the reactants in an attempt to improve the potential utilization of CO2. The effects of PEI loading, temperature, and coexisting gases (H2O, NO, and SO2) on CO2 adsorption performance were identified in a fixed bed. The results indicated that the adsorption capacity of the adsorbent toward CO2 was increased significantly after PEI impregnation. With the increase of temperature, the capture capacity of CO2 decreased because of the dominated thermodynamic control on the low PEI-loaded adsorbents, however, increased due to the governed kinetic control on the high PEI-loaded adsorbents. In addition, the adsorbent loaded with 20 wt % PEI showed the highest CO2 capture capacity, up to 1.07 mmol/g at 75 °C, and exhibited a 19.6% increase by introducing 10 vol % of water vapor. Meanwhile, the CO2 capture capacity was almost unaffected by NO; however, SO2 in flue gas could have some negative effects on CO2 adsorption due to the stronger acidity. Finally, the cyclic adsorption/desorption tests demonstrated excellent regenerability and stability of adsorbent. The results indicated that the PEI-modified porous MgCO3 is a very promising adsorbent for CO2 capture.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
SOLAR ENERGY MATERIALS AND SOLAR CELLS
·
2024
·
IF 6.3
Y.X. Xu,C.Y. Zhao
Thermochemical energy storage (TCES) is a pivotal technology for addressing the space-time mismatches in energy supply and demand. MgCO 3 /MgO carrier offers the advantages of high energy density , seasonal storage capability, and abundant nontoxic reserves. However, it is encumbered by poor exothermic activity and kinetic irreversibility . In this study, innovative preparation approaches for MgCO 3 /MgO have been developed, involving the regulation of physical morphology, so as to reveal the structure-activity relationship between pore morphology and TCES properties. The results indicate that SD-cotton-MgO (MgO prepared by structure-directing agent, cotton) could carbonate up to 76.98 %, facilitated by its mesopores that aid in the transport of reactants. SGSC-MgO (MgO prepared by sol-gel self-combustion method) exhibits the fastest reaction rate at the initial stage, with a rate of 593.1 μmol/min/g adsorbent because distributed macropores expose the other nanopores . As for SD-CPM-MgO (MgO prepared by structure-directing agent, carboniferous polysaccharide microsphere), owning to long pore distance of micropores hindering CO 2 diffusion, its kinetics gradually decreases as the CPM size decreases. Porous media with mixed aperture could exhibit strong kinetic performance. Furthermore, the heat storage density and maximum power of SD-cotton-MgO increase as the endothermic temperature rises, achieving a peak energy density of 1385.7 kJ/kg MgCO 3 at 400 °C. Still, its heat release density increases and then decreases with exothermic temperature, reaching 1964.3 kJ/kg MgO at 320 °C. Finally, the cycle stability is contingent on the activation of the chemical modification for the first heat release and antidegradation of the physical structure for subsequent cycles. SD-cotton-MgO doped with Na 0.5 K 0.5 NO 3 maintains at 50 % after 30 cycles, exhibiting no collapse or agglomeration due to its robust porous structure with strong thermal stability and permeability.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Small
·
2023
·Vol. 19
·期 45
·2303405
·
IF 13.3
Mengping Liu,Ganbing Zhang,Ruiqi Ming,Xin Fu,Ruiyi Jiang,Lihong Tian,Xiaobo Chen
Defects on metal oxide have attracted extensive attention in photo-/electrocatalytic CO 2 reduction. Herein, porous MgO nanosheets with abundant oxygen vacancies (V o s) and three-coordinated oxygen atoms (O 3c ) at corners are reported, which reconstruct into defective MgCO 3 ·3H 2 O exposing rich surface unsaturated -OH groups and vacancies to initiate photocatalytic CO 2 reduction to CO and CH 4 . In consecutive 7-cycle tests (each run for 6 h) in pure water, CO 2 conversion keeps stable. The total production of CH 4 and CO attains ≈367 µmol g cata −1 h −1 . The selectivity of CH 4 gradually increases from ≈3.1% (1 st run) to ≈24.5% (4 th run) and then remains unchanged under UV-light irradiation. With triethanolamine (3.3 vol.%) as the sacrificial agent, the total production of CO and CH 4 production rapidly increases to ≈28 000 µmol g cata −1 in 2 h reaction. Photoluminescence spectra reveal that V o s induces the formation of donor bands to promote charge carrier seperation. A series of trace spectra and theoretical analysis indicate Mg-V o sites in the derived MgCO 3 ·3H 2 O are active centers, which play a crucial role in modulating CO 2 adsorption and triggering photoreduction reactions. These intriguing results on defective alkaline earth oxides as potential photocatalysts in CO 2 conversion may spur some exciting and novel findings in this field.
研究领域:
材料科学
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环境科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FUEL
·
2022
·
IF 8.035
Qiaojuan Wang,Jianyue Wang,Wenjuan Rui,Dan Yang,Xiaoyue Wan,Chunmei Zhou,Renhong Li,Wen Liu,Yihu Dai,Yanhui Yang
Aqueous-phase reforming of biomass-derived formaldehyde is one of efficient and sustainable routes to generate molecular hydrogen as clean energy resource. In this work, Ag/MgCO 3 catalyst is prepared with constructed stable carbonate-modified metal-support interfaces. Under mild and neutral reaction conditions, it exhibits a near an order of magnitude higher low-temperature activity in formaldehyde reforming reaction for producing hydrogen in comparison with Ag/MgO. The catalytic and spectral observations reveal that the Ag/MgCO 3 -catalyzed reaction follows an O 2 -involved HCHO/H 2 O reforming reaction pathway through O 2 − , OOH and H radicals as highly active intermediates. Ag/MgCO 3 catalyst shows high rates in isotopic H 2 -D 2 exchange and HCHO/D 2 O reforming reactions and displays an apparent activation energy (E a ) as low as 7.5 kJ mol −1 within 10–50 °C, indicating facile activation of HCHO C H and H 2 O O H bonds. Furthermore, Ag/MgCO 3 catalyst adsorbs HCHO molecule in a favorable configuration and strength, as evidenced by the HCHO desorption profile. Comprehensive positive factors benefit to the superior hydrogen production activity of carbonate-modified Ag/MgCO 3 than Ag/MgO.
研究领域:
催化化学
·
可再生能源
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PROGRESS IN ORGANIC COATINGS
·
2022
·
IF 6.206
Kai Xing,Qinsheng Chen,Jixing Lin,Zunying Hu,Zhongxu Li,Jiayi Chen,Xueer Xu,Changdong Gu,Jiangping Tu
Polycaprolactone (PCL) based polymers are usually considered as potential coating materials for improve corrosion resistance of biodegradable magnesium alloy due to excellent mechanical property and biocompatibility. However, as for the quality and stability of the polymer-based coatings, the interfacial adhesion of polymer coating to magnesium substrate and the antibacterial ability should not be ignored. Herein, to improve the interfacial adhesion of PCL based coating, a MgO/MgCO 3 transition layer was prepared on the biodegradable WE43 magnesium alloy by a facile chemical conversion process in a deep eutectic solvent-based ionic liquid . Moreover, ZnO nanoparticles were loaded in the PCL to form a PCL/ZnO coating on the transition layer to further enhance corrosion resistance, biocompatibility, and antibacterial activity of the magnesium alloy substrate. Electrochemical corrosion test and in vitro biocompatibility tests, including cytotoxicity and antibacterial activity, were performed in a simulated body environment, which showed that the substrate covered by the double-layered coating possesses good corrosion resistance, biocompatibility and antibacterial ability.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES COMMUNICATIONS
·
2025
·
IF 7.7
Xiaojing Duan,Jiachen Zhu,Chenyang Li,Huidong Fang,Wanji Zhou,Shiai Xu
A mussel-inspired polydopamine-assisted layer-by-layer assembly combined with a metal-chelating strategy using phytic acid was employed to synthesize a novel multi-level core-shell magnesium carbonate-based flame retardant (AMC@PDA@PA-Ni) for enhancing the fire safety of ethylene vinyl acetate (EVA) copolymers. The incorporation of 50 wt% AMC@PDA@PA-Ni increased the LOI of the EVA composite to 30.3 %, achieving a UL94 V-1 rating. Compared to pristine EVA, the composite exhibited a 63.3 % reduction in peak heat release rate (pHRR) and a 66.7 % decrease in peak smoke release rate (pSPR). At elevated temperatures, the combined effects of AMC's gas-solid phase flame retardancy, the phosphorus-containing flame retardant's quenching action, and the transition metal nickel's catalytic charring capability significantly contributed to the composite's superior fire resistance. Additionally, the tensile strength of the EVA/AMC@PDA@PA-Ni composite increased by 97.6 % relative to EVA/AMC, attributed to the PDA modification, which enhanced filler dispersion and interfacial adhesion. This study introduces a facile and effective strategy for developing bio-based multi-level core-shell hybrid flame retardants with outstanding fire resistance and mechanical strength retention.
研究领域:
材料科学
·
火灾安全工程
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高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Nature Catalysis
·
2021
·Vol. 4
·期 5
·418-424
·
IF 41.813
Wang Hai,Wang Liang,Lin Dong,Feng Xiang,Niu Yiming,Zhang Bingsen,Xiao Feng-Shou
Strong metal–support interactions (SMSIs) are crucial for the preparation of supported metal catalysts. A prevailing view is that the redox feature of the metal oxide support is the driving force behind SMSI construction. Herein we demonstrate CO 2 -induced SMSIs between irreducible oxide MgO and noble gold nanoparticles, presenting electronic and geometric features that are similar to those of classical SMSIs. The key to these interactions is activating the oxide surface by a reversible reaction, MgO + CO 2 ⇆ MgCO 3 , which leads to migration of the support onto the gold nanoparticles to form thin overlayers. The overlayer is permeable to the reactant molecules, stable under the oxidation conditions and even water tolerant, resulting in sinter-resistant gold nanoparticle catalysts. This investigation provides an approach for the rational design and optimization of supported metal catalysts based on irreducible oxides, and deepens our understanding of the mechanism of SMSI formation.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）