FUEL
·
2022
·
IF 8.035
Qiangqiang Xue,Huilin Yi,Zhengwen Li,Zhao Jiang,Meng Chen,Yujun Wang,Binhang Yan,Guangsheng Luo
Surface modification of 600-µm-sized monodisperse gamma-alumina microspheres into magnesium–aluminum spinel, and co-impregnation-based loading of Rh–Ni (0.46 wt% Rh, 9.03 wt% Ni) were performed to synthesize catalysts for diesel-steam-reforming to hydrogen. The intimate interactions between Rh and Ni, the formation of the Rh–Ni alloy, and the Rh-doping-induced decrease in the particle size of Ni were determined. The DFT calculations results revealed that Rh-doped Ni(1 1 1) established remarkably weak bonds with oxygen-containing intermediates, and the reaction barrier of the rate-limiting step (CH 2 * + O* → CH 2 O*) on Rh–Ni(1 1 1) (0.76 eV) was lower than those of Ni(1 1 1) (1.14 eV) and Rh(1 1 1) (1.56 eV). The bimetallic catalyst shows the enhanced activity and resistance of sintering and carbon deposition compared with those of Ni-based (9.33 wt% Ni) and Rh-based (0.47 wt% Rh) catalysts. The catalytic performance of Rh–Ni-based catalyst was superior to that of physically mixed Ni-based and Rh-based catalysts at similar active metal loadings, which further confirmed the synergistic effect of Rh–Ni.
研究领域:
催化化学
·
能源材料科学
✓ 已验证
产品关联
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Yanxu Zhai,Lei Huang,Chengyou Wu,Luyao Jin
This study employs a co-calcination method, using Mg(OH) 2 and H 3 BO 3 to simulate the behavior of boron impurity (B) during the calcination of MgO expansive agent (MEA). The investigation included systematic monitoring of the characteristics and micro-morphologies of B-containing MEA (BMEA), the hydration process of cement pastes containing BMEA, and the compressive strength and expansion behavior of mortar specimens. The results indicate that, under the light-burned regime (LBR), B accelerates the hydration of MgO while delaying the hydration of cement, leading to reduced compressive strength, and enhanced expansion. Conversely, under the high-burned regime (HBR), B reduces the reactivity of MgO, thereby decreasing the expansion of the specimens during the first 35 days while increasing the expansion in the later stages. Through analyses of pore structure and micro-morphologies in BMEA-containing cement pastes, this study elucidates the differential impacts of BMEA on microstructural evolution under varying calcination temperatures, as well as the underlying mechanisms responsible for distinct expansion rates in specimens. These findings establish a theoretical foundation for the application of boron-containing magnesium slag in MEA production.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
ENERGY & FUELS
·
2018
·
IF 3.024
Yafei Guo,Chang Tan,Jian Sun,Weiling Li,Chuanwen Zhao,Jubing Zhang,Ping Lu
Nanostructured MgO sorbents show promise for intermediate-temperature CO2 capture from post-combustion flue gas stream. However, their CO2 capture behaviors can be affected by the magnesium precursors applied for sorbent synthesis. To screen potential precursors for fabricating excellent CO2 trappers, MgO nanoparticles (NPs) were synthesized by calcining several organometallic precursors, including magnesium ethoxide, magnesium acetate tetrahydrate, magnesium oxalate dehydrate, magnesium lactate dihydrate, magnesium citrate nonahydrate, and magnesium gluconate hydrate. The precursors and MgO NPs were characterized by thermogravimetric analysis, X-ray diffraction, N2 adsorption–desorption, field emission scanning electron microscopy, and CO2 temperature-programmed desorption. A fixed-bed reactor was used to evaluate the CO2 capture performances of the MgO NPs in a simulated flue gas stream. The effect of organometallic precursors on CO2 capture behaviors of the sorbents was further demonstrated. Results indicated that the different precursors would yield MgO NPs with distinct textural and surface properties, and these could further affect their CO2 capture behaviors. MgO NPs derived from magnesium oxalate dehydrate exhibited the highest CO2 uptake of 4.41 mmol of CO2/g. The excellent CO2 uptake was mainly attributed to its superlative textural properties, uniform surface morphology, and abundant base sites.
研究领域:
材料科学
·
环境工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
·
2020
·
IF 5.006
Xuefei Wang,Yong Men,Jinguo Wang,Shuang Liu,Qiaoling Song,Mei Yang
Catalytic transformation of ethanol has been studied over a series of MgO-SiO 2 composite catalysts with different ZnO loadings. Vast differences in product selectivity are obtained by varying ZnO loadings in enabling the control over product distribution. Our results reveal that MgO-SiO 2 composite catalysts with low ZnO loadings tend to show an enhanced efficiency for C C bond coupling and exceptionally high selectivity to 1,3-butadiene whereas the high ZnO loadings favor the formation of acetaldehyde via dehydrogenation. Thorough analysis of characterization results via XRD, BET, IR, TPD, and 29 Si MAS NMR indicates that ZnO loading influences the extent of MgO and SiO 2 interaction during preparation, and the surface acid-base chemistry, which were both found to correlate with the catalytic performance. This study proposes that the Mg O Si interfacial structure formed by the strong MgO and SiO 2 interaction at low ZnO loadings is of prime importance for the formation of 1,3-butadiene, benefiting from the desirable properties of balanced dehydrogenation and C C bond coupling while excess ZnO loadings destroy the Mg O Si interfacial bonds over the MgO-SiO 2 composite catalysts, which are the key structures required for C C bond growth.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Scientific Reports
·
2021
·Vol. 11
·期 1
·1-17
·
IF 4.38
Liu Ju,Chen Fei,Yang Wenbing,Guo Jianjun,Xu Guangwen,Jia Fenglei,Shi Lei
The activities of various MgO catalysts, which were prepared from different methods such as hydration synthesis, thermal decomposition, combustion, sol–gel and co-precipitation, were conducted in dimethyl carbonate (DMC) synthesis via transesterification of ethylene carbonate with methanol. MgO-P-Na 2 CO 3 -3.14 synthesized by the excess Na 2 CO 3 precipitation compared the best catalytic activity and stability, which could be reused for seven times without obvious deactivation. The DMC yield was as high as 69.97% at 68 °C. The transesterification reaction could be separated into two steps, and the samples obtained by NaOH precipitant exhibited better ring-opening capability, while the catalysts acquired by Na 2 CO 3 precipitant displayed superior transesterification ability. The structure-performance relationship was evaluated by multiple characterization methods. The results indicated that the as-synthesized catalyst derived from dried precursors with more crystalline magnesium carbonate was favorable for the promotion of DMC yield, and MgO-P-Na 2 CO 3 -3.14 with more Mg-O pairs, which were the active center for the transesterification of 2-hydroxyethyl methyl carbonate (HEMC) intermediate with methanol, resulted in more moderately basic sites left that was in accordance with the DMC yield variation. MgO-P-Na 2 CO 3 -3.14 with greater BET surface area and mesopore volume, relative low surface oxygen content and larger moderately basic sites amount compared the excellent activity in DMC synthesis.
研究领域:
化学工程
·
催化材料科学
✓ 已验证
DOI
PubMed
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 25
·15477-15485
·
IF 3.361
Fengjiao Li,Liguo Wang,Shuang Xu,Shuting Liang,Ningning Zhang
Developing cost-effective, high-efficiency and heterogeneous catalysts is of prime importance for the green synthesis of diethyl carbonate (DEC) from ethyl carbamate (EC) and ethanol. Herein, a series of MgO/γ-Al2O3 catalysts were readily fabricated by an impregnation method for DEC synthesis from EC and ethanol. The activities of the as-prepared MgO/γ-Al2O3 catalysts as well as the individual MgO or γ-Al2O3 were first tested in the batch reactor. Among the investigated samples, the MgO/γ-Al2O3 with a MgO loading of 10 wt% (denoted as 10% MgO/γ-Al2O3) exhibited the largest amount of stronger basic sites, and the highest activities with EC conversion of 41.8% and DEC yield of 30.4%, respectively. Furthermore, the DEC yield was greatly boosted to 52.1% with a high DEC selectivity of 93.8% over the 10% MgO/γ-Al2O3 catalyst under the optimized reaction conditions in the fixed bed reactor, outperforming most of the reported catalysts.
研究领域:
催化化学
·
绿色化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Jinhui Zhang,Linlin Chang,Xinfeng Zhu,Jia Yao,Aoxuan Bai,Junning Wang,Rongfu Peng,Guofeng Li,Libin Jiang,Kai Wang,Xueping Liu,Shiqiang Yin,Chaohai Wang
Large quantities of MgO materials have been obtained by roasting waste magnesite. Compared with the traditional MgO synthesis method, the preparation method in this paper is simple, inexpensive, environmentally friendly, and can be produced on a large scale. XRD and XPS results show that the main component of the magnesite roasted product is MgO. The SEM results show that after hydration treatment and secondary roasting, the morphology of MgO changed from granular to flower-like. XRD and XPS before and after the reaction showed that a hydration reaction (Mg(OH) 2 ) could take place when MgO activates PMS. The activity results showed that MgO was able to remove 96 % of the doxycycline within 30 min, which was significantly higher than that of the conventional MOF materials and comparable to the ZIF-67 activity of the cobalt-based MOF materials. In addition, MgO has superior catalytic activity for Congo red (90.59 %), methyl orange (40.04 %), and tetracycline (98.85 %). Quenching experiments revealed 1 O 2 as the main active species. The material has good potential for practical applications as shown by anion interference experiments, pH and cycling experiments. The optimum reaction condition is when the MgO content is 0.6 g/L and the PMS content is 0.6 g/L.
研究领域:
环境科学
·
材料科学
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产品关联
DOI
高影响因子
Surfaces and Interfaces
·
2023
·
IF 6.2
Xiyue Li,Yanjing Liu,Fuming Wang,Yaping Huang,Xuyang Feng,Botian Zhu,Yuezhou Liu,Yongfang Qian,Lihua Lv,Ying Wang
The purpose of this research was to obtain the composite nanofiber membranes with efficient antibacterial property using synthetic magnesium-based antibacterial agents. Based on the antibacterial mechanism of MgO nanoparticles (MgONPs), the MgO nanorods (MgONRs) with surface nano textures (M-SNT) were designed to increase the effective contact area of MgONRs and bacteria, which achieved an excellent antibacterial property. The effect of the calcination temperature on the surface nano textures morphological and the antibacterial property of the M-SNT were systematically researched. When the calcination temperature reached 600 °C (M-SNT6), the surface nano textures of M-SNT6 was uniform and the antibacterial property was the most excellent, and the antibacterial rate was better than that of the commercial MgONPs (C-M). The highly-effective antibacterial nanofiber membranes were fabricated by loading 2.5 wt% M-SNT6 on polycaprolactone/polyvinyl pyrrolidone (PCL/PVP) substrates through electrospinning technology, which presented excellent antibacterial rate of 100% against E. coli .
研究领域:
材料科学
·
生物学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
·
2022
·Vol. 29
·期 47
·71721-71730
·
IF 5.19
Huang Wenjun,Li Sichao,Wang Hongbin,Cui Peng,Xu Haomiao,Cheng Can,Qu Zan,Yan Naiqiang
Oxidation–reduction-absorption based on sulfite is a promising process for simultaneous removal of NO x and SO 2 . However, excessive oxidation of sulfite and competitive absorption between NO x and SO 2 limit its application. A matching strategy between antioxidants and alkaline agents has been proposed to solve these problems and enhance the absorption process. The comparison results of inhibitors showed that hydroquinone exhibited long-term high-efficiency inhibition of S(IV) (SO 3 2- /HSO 3 - ) oxidation. The comparison of alkaline agents showed that the Na 2 SO 3 solution with heterogeneous mixture of MgO and hydroquinone exhibited better absorption performance than that with other combinations. The absorption amounts of NO x in 0.15 mol/L Na 2 SO 3 50 mL solution added 0.1% hydroquinone (HQ) with 0.09 mol/L MgO were 2.24 mmol, which improved 5 times than that without additives. In addition, studies on the influence of pH showed that the pH of MgO mixture could be stabilized at 9–10 for a long time, while the pH of Na 2 CO 3 mixture decreased faster. Further studies suggested that the hydration of MgO resulted in the solution with MgO keeping high pH. This is also the main reason why the combination of MgO and hydroquinone is superior to the combination of Na 2 CO 3 and hydroquinone in desulfurization and denitration performance.
研究领域:
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2020
·
IF 4.419
Yang Chen,Chengji Deng,Xing Wang,Jun Ding,Chao Yu,Hongxi Zhu
Si 3 N 4 -MgO-C refractories were prepared using fused magnesia, flake graphite, and Si powder-supported Fe(NO 3 ) 3 ·9H 2 O as the raw materials and phenolic resin as the binder under the flow of N 2 . The effect of different nitriding temperatures on the morphology and production of Si 3 N 4 in the uncatalyzed refractories was investigated. The effect of the morphology of β-Si 3 N 4 on the properties of the refractories with different catalyst contents was investigated. The oxidation resistance of the refractories was also investigated. The results showed that the increase in the nitriding temperature was beneficial for the formation of β-Si 3 N 4 in the refractories. However, very high nitriding temperatures generated a large number of pores in the refractories and deteriorated their properties. The refractory with 1 wt% catalyst exhibited good mechanical properties and oxidation resistance. However, the addition of excessive catalyst inhibited the formation of β-Si 3 N 4 and deteriorated the performance of the refractories.
研究领域:
材料科学
·
无机化学
✓ 已验证
产品关联
DOI
高影响因子
Desalination and Water Treatment
·
2015
·
IF 1.173
Jun Chen,Shuanghong Tian,Lingjun Kong,Yuting Tu,Jiang Lu,Ya Xiong
An integrated heterogeneous catalytic ozonation and membrane separation system was studied for continuous degradation of refractory organic pollutants in water. MgO nanosheets with dominant (111) facets showed large amounts of medium and strong basic sites due to the particular structure of alternating monolayers of exclusively oxygen and exclusively magnesium atoms. MgO(111) acted as the ozonation catalyst for the first time, it was found that efficient degradation of nitrobenzene was achieved with 25.0 mmol/L of MgO(111) catalysts in a wide pH range of 4.0–12.0. In view of practical application, engineering problems to recover fine size catalysts from the treated water were resolved by applying membrane separation technology in the system. Experimental results showed that the membrane could successfully intercept MgO(111) particles in the reactor by the synergistic cooperative sieving of the bare and dynamic membranes. The long-term continuous experiments demonstrated that the removal rate of nitrobenzene could maintain over 90% with a constant flux of 3.92 L m−2 min−1 during the 24 h operation. The continuous system provides a new method for practical application of heterogeneous catalytic ozonation to remove refractory organic pollutants.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Catalysis
·
2024
·
IF 11.3
Xiaohong Ren,Qian Qiang,Zhuohua Sun,Ting Wei,Xiaoqiang Yu,Zeming Rong,Changzhi Li
This work demonstrates the upgrading of lignin-derived monomers through a cascade demethoxylation, aqueous-phase reforming reaction, eliminating the need for external hydrogen supply. The core of this research lies in the use of neat water as both reaction medium and the hydrogen donor over a multifunctional Ni/MgO catalyst, which is responsible for water splitting, aqueous-phase reforming of in situ generated methanol, and selective cleavage of the C–O bond, finally establishing an efficient one-pot approach achieving a high yield of phenols. Reaction mechanism studies proved that the initial H* source came from water by its splitting on the surface of the Ni/MgO catalyst, which triggered the fracture of the aromatic ether bond to afford phenols and CH3O*. The subsequent aqueous-phase reforming of CH3O* and OH* generated more hydrogen and further accelerated the hydrodeoxygenation (HDO) process. A high conversion of 87.8% with a selectivity of 88.9% for phenol could be achieved at 190 °C from guaiacol. Thanks to the interesting water-splitting mechanisms and strong metal–support interaction (SMSI), Ni/MgO exhibited significantly enhanced stability compared to the previously reported nanoporous Ni catalysts. Further, with real lignin as the substrate, 16.3 wt % combined yield of phenol and 4-methylphenol could be acquired under optimized conditions. Overall, this “H2-free” approach offers a promising alternative to conventional biorefinery processes, addressing the challenges of hydrogen sourcing and economic feasibility.
研究领域:
催化化学
·
生物质能
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）