CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2020
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IF 2.627
Tong Luo,Shaolong Liu,Cong Luo,Xiaolei Qi,Bowen Lu,Liqi Zhang
CaO based sorbents have great potential for commercial use to capture CO 2 of power plants. In the demand of producing sorbents with better cyclic performance, CaO-based sorbents derived from different kinds of calcium precursors, containing calcium carbonate (CC-CaO), calcium gluconate monohydrate (CG-CaO), calcium citrate (CCi-CaO) and calcium acetate monohydrate (CA-CaO), were tested cyclically and compared using simultaneous thermal analyzer (STA). And further study was conducted on the sorbents modified with citric acid monohydrate and 50% gluconic acid solution by wet mixing combustion synthesis. The modified sorbents showed better performance and higher pore parameters as well as porous microstructure with more organic acid added. After 20 cycles of carbonation and calcination , the C2CCi8 (CaO: citric acid = 2:8 by mass ratio) and C2G8 (CaO: gluconic acid = 2:8 by mass ratio) sorbent possess CO 2 capture capacity of 0.45 g·g −1 (g CO 2 per g sorbents) and 0.52 g·g −1 respectively. The citric acid was more effective for modification than gluconic acid for extended 50 cycles. Furthermore, good linear relationship between CaO conversion and specific surface area as well as pore volume were determined, of which the specific surface area showed closer correlation with CaO conversion.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2024
·Vol. 35
·期 1
·1-14
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IF 2.8
Zhang Yajuan,Lu Yang,Shan Yiting,Wang Jie,Feng Jingmin,Zhou Hongqing
Herein, (1 − x )CaO–Al 2 O 3 –B 2 O 3 –SiO 2 (CABS)/ x Ba(Mg 1/3 Nb 2/3 )O 3 (BMN; x = 0.4, 0.45, 0.5, 0.55, and 0.6) composites were prepared, and the impact of the BMN and low-softening-point glass content in CABS/BMN composites on the sintering, dielectric, thermal, and mechanical properties of the prepared composites was investigated. The main crystal phases of the CABS/BMN composites are BMN and Ba 2 NaNb 5 O 15 (BNN). The crystallization temperature of the composite was reduced by an appropriate amount of BMN. BMN ceramics (40–60 wt%) was added to the CABS glass, and the composites were sintered at 800 °C, 825 °C, 850 °C, 875 °C, and 900 °C. To elucidate the influence mechanism of different glass contents and sintering temperatures on the properties of the composites, different qualitative and quantitative instruments were used to study the composite properties. The CABS/BMN composite containing 50 wt% CABS glass sintered at 875 °C exhibits the following ideal properties: volumetric density of 3.57 g/cm 3 , dielectric constant of 17.97, dielectric loss of 6 × 10 −4 , \(Q \times f\) value of 10,947 at 9.5 GHz, bending strength of 157.7 MPa, and coefficient of thermal expansion of 5.9 ppm/K. Microstructure analysis reveals that the microstructure of the composite is dense, the pores are few, the surface morphology is uniform and flat, and the composite does not react with silver electrodes, making it suitable for applications utilizing medium dielectric constant low-temperature co-fired ceramic materials at low sintering temperatures.
研究领域:
材料科学
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电子工程
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DOI
高影响因子
INFRARED PHYSICS & TECHNOLOGY
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2024
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IF 3.1
Yin Liu,Jie Wan,Yongbao Xiao,Dechao Yu
Glass forming regions of Al 2 O 3 -CaO-SrO (AlCaSr) system were systematically studied and clearly depicted by a combination of thermodynamic calculation method and traditional melt-quenching experiments. The glass forming region was first found with a composition range of Al 2 O 3 : 12–32 mol%, CaO: 43–68 mol%, and SrO: 20–36 mol%. Moreover, two representative glass compositions, 26.6Al 2 O 3 -49.4CaO-24SrO (AlCaSr-1) and 17.48Al 2 O 3 -58.52CaO-24SrO (AlCaSr-2), in central part of the experimental glass forming region and the corresponding glass doped with 1 mol% Er 2 O 3 , i.e., AlCaSr-1-Er and AlCaSr-2-Er, were selected and carefully prepared in our lab. Detailed investigations proved that the AlCaSr glasses had excellent comprehensive properties with high T g temperature (∼ 800 °C), wide transparency wavelength range (0.3–6 μm), and low maximum phonon energy (∼ 770 cm −1 ), and good 2.7 μm mid-infrared emitting properties via doping Er 3+ activators. These results highlight the potential application of AlCaSr glasses as infrared materials, and could benefit the development of high-performance infrared glasses.
研究领域:
材料科学
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光学
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DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2025
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IF 6.2
Wenzhe Zhang,Shanshan Dai,Yong Liu,Jie Li,Guozhang Chang,Cuiping Wang,Jian Zhang
The utilization of industrially generated lignin is an important aspect of achieving worldwide carbon neutrality. In this study, Ni/CaO, Ce/CaO and (Ni-Ce)/CaO catalysts were prepared using an impregnation method to improve the production of H 2 -enriched syngas from lignin steam gasification. Results show that the Ni/CaO and Ce/CaO exhibited different effects when applied to steam gasification, the former improved the conversion of solid lignin whereas the latter promoted decomposition of the resulting volatiles. The (Ni-Ce)/CaO catalyst provided a remarkable synergistic effect on production of H 2 -enriched syngas. The mass-based yield of gaseous products and the volume-based proportion of H 2 in these products were respectively 70.8% and 61.1% in the presence of the (Ni-Ce)/CaO catalyst with a Ni-to-Ce molar ratio of 1:0.9. The H 2 yields obtained from this material were found to gradually decrease from 763 to 681 mL/(g lignin) during five repeated uses. This gradual deactivation of the (Ni-Ce)/CaO catalyst was ascribed to both carbon deposition and the formation of CaSO 4 by reactions between sulfur in the lignin ash and the CaO component.
研究领域:
能源工程
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催化
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生物质利用
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化学工程
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环境科学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2025
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IF 2.5
Junying Fu,Min Lu,Kejing Fang,Pengmei Lv,Zuhong Xiong
Biodiesel, a renewable liquid fuel, is undergoing eco-transition in catalyst research and development. Calcium oxide (CaO) was a widely studied heterogeneous catalyst due to its considerable activity. However, the poor stability of CaO during storage in air, especially by CO2 and H2O poisoning, presents a challenge. This research successfully developed a high-activity CaO/La2O3 catalyst for biodiesel production with CaO nanoparticles well-dispersed on the La oxide support (Ca/La=0.12). Under mild reaction conditions, a fatty acid methyl esters (FAMEs) yield of 96.9% was achieved. After exposure to air for two weeks, the CaO/La2O3 (Ca/La=0.12) catalyst absorbed 49% less CO2 and 91% less water than pure CaO and keeps 71.4% of the original activity. Thermogravimetric and in-situ Fourier Transform Infrared Spectroscopy analysis reveal that CO2 and H2O will preferentially be captured by La oxides and keep the supported CaO active sites safe. DFT calculations confirmed that CO2 and H2O adsorption on CaO terrace sites became an unfavoured process due to lattice compression of CaO nanoparticles on La2O3, which imparts the CO2/H2O-proof property to CaO/La2O3 catalyst. Methanol adsorption, dissociation, and migration pathways on CaO/La2O3 that produce active methoxy anions at Ca-La interfaces were identified as key steps in achieving efficient catalytic reactions.
研究领域:
化学工程
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催化材料
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可再生能源
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DOI
高影响因子
ENERGY & FUELS
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2021
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IF 3.605
Yue Zhou,Zijian Zhou,Lei Liu,Xiangyao She,Ruichang Xu,Jian Sun,Minghou Xu
Calcium looping is a potential thermochemical energy storage technology applied in a high-temperature working window. However, CaCO3/CaO materials are prone to encounter severe sintering, exhibiting poor thermal energy storage/release stability. To improve the thermochemical energy storage stability, different amounts (5, 15, and 30 wt %) of a Zr-based stabilizer were incorporated into CaCO3/CaO materials. Moreover, the graphite-casting method was adopted to prepare the Zr-stabilized, CaO-based composite pellets aiming to improve the practicability. The incorporation of the Zr-based stabilizer can effectively resist the sintering of CaO-based composite powders during a high-temperature precalcination process. It is mainly attributed to the large amounts of generated, nanosized CaZrO3 grains possessing desirable antisintering ability evenly distributed within the composites. Particularly, the Zr-stabilized, CaO-based composite pellets containing 30 wt % of CaZrO3 possess a relatively high compression strength of 2.28 ± 0.87 MPa and a desirable thermal storage density of 1.15 GJ/t after 20 cycles. Additionally, the graphite-casted, Zr-stabilized, CaO-based composite pellets have potential to be applied in a large-scale thermochemical energy storage system because the graphite-casting method is easy to be scaled-up.
研究领域:
材料科学
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储能技术
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热能工程
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产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
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2024
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IF 8
Yang-Yang Hao,Ming-Xiu Xiao,Guo-Cui Mao,Jin-Peng Wang,Zhan-Kuo Guo,Bao-Xia Dong,Yun-Lei Teng
Capturing CO 2 using clamshell/eggshell-derived CaO adsorbent can not only reduce carbon emissions but also alleviate the impact of trash on the environment. However, organic acid was usually used, high-temperature calcination was often performed, and CO 2 was inevitably released during preparing CaO adsorbents from shell wastes. In this work, CaO-based CO 2 adsorbent was greenly prepared by calcium-induced hydrogenation of clamshell and eggshell wastes in one pot at room/moderate temperature. CO 2 adsorption experiments were performed in a thermogravimetric analyzer (TGA). The adsorption performance of the adsorbents obtained from the mechanochemical reaction (BM-C/E-CaO) was superior to that of the adsorbents obtained from the thermochemical reaction (Cal-C/E-CaO). The CO 2 adsorption capacity of BM-C-CaO at 650 °C is up to 36.82 wt%, but the adsorption decay rate of the sample after 20 carbonation/calcination cycles is only 30.17%. This study offers an alternative energy-saving method for greenly preparing CaO-based adsorbent from shell wastes.
研究领域:
环境科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
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IF 4.175
Yao Fu,Jian Li,Pengzhen Li,Huajie Tao,Xianfu Luo,Dongjian Wang,Yiting Shan,Hongqing Zhou
In this work, the titanate coupling agent KR-TTS was used in tape casting of CaO–B 2 O 3 –SiO 2 (CBS) glass-ceramics to obtain a high-performance dielectric tape. The functional group ((RO) m ) of KR-TTS could directly react with the hydroxyl (–OH) of the CBS powders, which made the feature of powders from hydrophilicity into hydrophobicity . The modification mechanism of the modifier KR-TTS was illuminated by infrared absorption spectrum and contact angle of powders with modifier KR-TTS. The optimum amount of KR-TTS was determined by the rheological properties of suspensions, the density and the tensile strength of the green samples, the density and dielectric properties of the sintering samples sintered at 835 °C. The surface modification of CBS glass-ceramic by KR-TTS has made a substantial breakthrough in improving the densification and the mechanical performance of the green tapes. When the amount of KR-TTS was 1.0 wt%, the stability of slurry and the properties of the green samples had been greatly improved. The density of the green samples with 1.0 wt% KR-TTS reached 1.59 g/cm 3 and the tensile strength of the green samples reached 2.43 MPa. The sintering sample with 1.0 wt% KR-TTS realized sintering densification and performed better dielectric properties. The sintering density reached to 2.51 g/cm 3 . The permittivity and dielectric loss were ε r = 5.92 and tanδ = 13 × 10 −4 at 10 GHz.
研究领域:
材料科学
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无机非金属材料
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电子材料
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产品关联
DOI
高影响因子
Reaction Kinetics Mechanisms and Catalysis
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2024
·
IF 1.7
Gao Hang,Zhu Yuqin,Luo He’an,Lv Yang,Liu Pingle
Co–xCaO/g-C 3 N 4 catalysts were prepared using incipient wetness impregnation method and applied in isophthalonitrile hydrogenation to M-xylenedimethylamine. The characterization results and experimental data indicate that introduction of CaO crates large number of basic sites and leads to electron rich Co, hence inhibits the side reaction and improves the selectivity to M-xylenedimethylamine. 10Co–2CaO/g-C 3 N 4 gives the best catalytic performance of 100% conversion of isophthalonitrile and 95% selectivity to M-xylenedimethylamine without any alkaline additives in the reacion system. This work is valuable for the design and preparation of hydrogenation catalysts with rich basic sites and provides a green process for nitrile compounds to amine.
研究领域:
催化化学
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绿色化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Jinchen Ma,Daofeng Mei,Weiwei Peng,Xin Tian,Danyan Ren,Haibo Zhao
Calcium looping (CaL) is extensively used in post-combustion capture of CO 2 and sorption-enhanced steam methane reforming because of its advantages of low cost and theoretically high CO 2 -capture capacity. Despite this, unstable reactivity of sorbent (CaO) and significant heat requirement for CaCO 3 calcination were always encountered in CaL. To address the aforementioned issues, a core-shell structured CaO-CuO/MgO@Al 2 O 3 sorbent (CCMA for short) was synthesized via the self-assembly template synthesis (SATS) method, and systematically investigated in terms of carbonation, calcination-reduction and oxidation cycles. In comparison to wet-mixing CaO-CuO material (CC), MgO-supported CaO-CuO (CCM) and Al 2 O 3 -supported CaO-CuO (CCA), the CCMA performed the highest CO 2 uptake capacity, which was quite stable at around 0.08 [g CO 2 ∙(g material) −1 ] in the 30 cyclic tests. In calcination-reduction stage, CaO in CCMA can be fully recovered by the decomposition of CaCO 3 , meanwhile the corresponding heat requirement can be compensated by the exothermic reaction between CuO and CH 4 , i.e., thermal neutrality can be achieved by using CCMA. The Cu in reduced CCMA can be subsequently oxidized back to CuO in the oxidation stage with a conversion of 97–98%, which is much higher than CC, CCM and CCA. After cycles, no serious sintering was observed for the CCMA and the measured crushing strength (1.4 N) was sufficient for fluidization, which, in combination with its high reactivity, makes this material very promising for CaL-CLC process.
研究领域:
能源科学
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材料科学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2025
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IF 6.3
Zhitao Shan,Yuanyuan Kang,Jiayan Zhang,Yanfei Zhang,Qiuju Zheng,Shujiang Liu,Haizheng Tao,Yuanzheng Yue
The hardness ( H v ) and crack initiation resistance ( C R ) of oxide glasses are crucial properties for various applications, such as in vehicles, display devices, and buildings. However, these properties are still limited for many special applications. Here, we studied the evolution of the H v and C R with varying the ratio R = [Al 2 O 3 ]/[CaO] in the low silica (0 and 17 mol% SiO 2 ) aluminate glasses, i.e., so called silico-aluminate glasses, and thereby identified a composition that exhibits the highest C R and H v . The results showed that the H v decreased with increasing R within the peraluminous region. Furthermore, a significant increase in C R value with increasing R was detected in the range of R = 1.0–1.18. In contrast, the glass series containing 50 mol % SiO 2 content exhibited only a slight increase in C R value, but pronounced increases in both T g and H v with increasing R in the peraluminous region. The Raman spectroscopy revealed that [5]Al and oxygen tri-cluster ([3]O) are the controlling factors for C R and H v of the studied glasses. Moreover, the impact of [3]O and [5]Al on H v and C R is highly dependent on the SiO 2 content in the studied glasses.
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高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Dongsheng Jiang,Yuzhe Li,Chao Zhang,Ruifang Wang,Jinpeng Zhu,Wen Chen,Yusi Che,Jilin He
Bayan Obo tailings are rich in niobium and other valuable elements; however, the phase evolution of niobium-bearing slag within these tailings remains poorly understood. This knowledge gap significantly impedes comprehensive utilization of these strategic resources. In this study, a CaO-SiO 2 -Nb 2 O 5 -5%Na 2 O-5%Al 2 O 3 -3%CaF 2 slag system was investigated to examine the phase equilibrium types, compositional characteristics, and distributional evolution under varying w (CaO)/ w (SiO 2 ) ratios and w (Nb 2 O 5 ) contents, using high-temperature equilibrium experiments. Following a 24-hour high-temperature equilibrium treatment at 1473 K under an argon atmosphere, a range of compounds including 13CaO·8SiO 2 ·Nb 2 O 5 ·CaF 2 , 2CaO·4SiO 2 ·Na 2 O·Al 2 O 3 , CaO·Nb 2 O 5 ·NaF, 2CaO·Nb 2 O 5 , and CaO·SiO 2 were identified. An increase in Nb 2 O 5 content coupled with a reduction in the w (CaO)/ w (SiO 2 ) ratio favored the formation of CaO·Nb 2 O 5 ·NaF (pyrochlore phase) and 2CaO·Nb 2 O 5 . These two phases exhibited high Nb concentrations, with the CaO·Nb 2 O 5 ·NaF (pyrochlore) phase containing up to approximately 70% Nb. The optimal smelting conditions for niobium enrichment in the pyrochlore phase were identified within the range of w (CaO)/ w (SiO 2 ) = 0.74∼0.80 and w (Nb 2 O 5 ) = 13.61%∼16.11%.
研究领域:
冶金学
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材料科学
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矿物加工
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物理化学
✓ 已验证
产品关联
DOI
高影响因子