CHEMICAL ENGINEERING JOURNAL
·
2021
·
IF 13.273
Jun Mou,Xingqi Fan,Fei Liu,Xiaodan Wang,Tianxiang Zhao,Peng Chen,Ziwei Li,Chunliang Yang,Jianxin Cao
The direct conversion of CO 2 hydrogenation to lower olefins via methanol as an intermediate is of great significance, but challenges still remain. Herein, we present a binary Mn 2 O 3 -ZnO oxide, which is responsible for catalytic hydrogenation of CO 2 to methanol. After combination of Mn 2 O 3 -ZnO and SAPO-34 molecular sieve, the catalytic reaction displays a markable increase. CO 2 adsorption by alkaline nature, followed by oxygen vacancy activation and synergistic hydrogenation over the binary Mn 2 O 3 -ZnO oxide are the prerequisites for the tandem reaction. However, the tandem spacing between oxide and molecular sieve plays a crucial role, because the suitable intimacy can induce enhanced methanol formation as intermediate via tandem dynamics effect, causing an apparent limitation for reverse water gas shift reaction at high temperature. The optimum mass ratio of 3:1 for two phases demonstrates that more components of binary oxide are needed to improve the rate of CO 2 hydrogenation to methanol, aiming to balance the two-step tandem reaction. Finally, under conditions of 380 ℃, 3 MPa and 3600 mL/g cat /h, 20%Mn 2 O 3 -ZnO/SAPO-34 tandem catalyst is obtained by physical ball milling after 15 min, with excellent stability, sulfur tolerance and catalytic performance with CO 2 conversion at almost 30%, lower olefins selectivity of 80.2% (propylene/ethylene = 5.6:1), and single-pass yield of 10.7%.
研究领域:
催化化学
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能源化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zhiyuan Zhang,Guixia Fan,Guoli Zhou,Daoguang Teng,Hongyan Nan,Peng Li,Yijun Cao,Jiongtian Liu
Germanium, a critical metal, is predominantly located in lignite and lead–zinc ore. The germanium was commonly extracted from the fly ash of germanium-rich lignite (GRL), however, facing the challenges of specific combustion conditions, low lignite’s thermal efficiency and value, high CO 2 emissions, and waste acid treatment. Therefore, in this work, a novel method for directly leaching germanium from the GRL was proposed, facilitating low-carbon extraction under mild conditions, and reducing lignite loss during leaching process. Results showed that leaching germanium from the GRL using thionyl chloride achieved the goals of “kill two birds with one stone”, i.e. , leaching efficiency of germanium above 95 wt % and recovery yield of lignite over 95 wt %. Specifically, the theoretical leaching efficiency of germanium reached 99.60 wt % while the recovery yield of lignite reached 86.35 wt %, at the temperature of 20 °C, liquid–solid ratio of 4 mL/g, and leaching time of 6 h. Most of the leached germanium was remained in the aqueous phase after the leaching solution was quenched, facilitating the subsequent separation of germanium. In this study, efficient extraction of germanium from the GRL was achieved with a high recovery yield of lignite, preserving the matrix structure and main composition of lignite. Therefore, this method provides a feasible way for efficient extraction of germanium from lignite with low-carbon emission under mild condition.
研究领域:
材料科学
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of CO2 Utilization
·
2018
·
IF 5.503
Jianyang Wang,Anfeng Zhang,Xiao Jiang,Chunshan Song,Xinwen Guo
Although many researchers have reported CO 2 hydrogenation to various C1 chemicals, it is still challenging to directly and selectively convert CO 2 to C 2 -C 4 hydrocarbons in terms of overcoming the extreme inertness of CO 2 and a high C C coupling barrier. In the present work, we report an efficient integration of methanol-synthesis and the methanol-to-hydrocarbons with the bifunctional catalyst component of In 2 O 3 -ZrO 2 and SAPO-5. These tandem reactions exhibit an excellent relative selectivity of C 2 -C 4 (83%) with a suppressed CH 4 relative selectivity less than 3% at T = 300 °C. A detailed analysis indicates that the partially reduced indium oxide surface (In 2 O 3 -ZrO 2 ) can better activate CO 2 and promote the synthesis of methanol than In 2 O 3 alone, and C C coupling is subsequently manipulated within the confined acidic pores of SAPO-5 according to XRD, H 2 -TPR, CO 2 -TPD, SEM and TEM. Furthermore, the proximity of two components and the content of Si also play an important role in such outstanding selectivity to C 2 -C 4 . Our study paves a new path for the direct synthesis of lower hydrocarbons.
研究领域:
化学工程
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催化化学
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能源化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
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2024
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IF 5.6
Meilu Hao,Peng Liang,Miaomiao Tian,Songze Li,Yue Gao,Yaqing Zhang,Xizhuang Qin,Wenrui Zhang,Tiantian Jiao
To efficiently utilize the oxygenated structures in lignite and obtain value-added oxygenated compounds, this study proposes a low carbon cascading utilization of Zhaotong lignite (ZT) through thermal dissolution and pyrolysis. The selectivity of ethanol (ET), tetrahydrofuran (THF) and ethyl acetate (EA) for oxygenated compounds in thermal dissolution, and the enrichment of thermal dissolution-pyrolysis on oil phases were investigated. The results show that sequential thermal dissolution is selective for different oxygenated compounds in ZT. ET shows selectivity for esters at 350 °C-2 MPa and for phenols at 350 °C-6 MPa. THF and EA are selective for naphthols and esters at 350 °C-6 MPa, respectively. Compared with the single process of thermal dissolution or pyrolysis, thermal dissolution-pyrolysis can significantly increase the oil phases yield with high value-added, in which ET, THF and EA increase the oil phase yields by 24.81 wt%, 13.66 wt% and 7.90 wt%, respectively. In particular, 59.15 wt% of the oxygen is distributed in light oil, and 9.79 % phenols as well as 1.56 % esters are enriched into light oil during thermal dissolution-pyrolysis process of ET. High value-added oxygenated compounds can be selectively enriched by appropriate solvents, at the same time, the quality of pyrolysis tar can be improved and the carbon emissions could be reduced.
研究领域:
化学工程
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能源科学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
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IF 11.889
Zhenyu Zhai,Junfeng Su,Amjad Ali,Liang Xu,Fazli Wahid
This study emphasizes on the cellulase production characteristics of strain ZY7 and its collaboration with nitrate-dependent ferrous oxidizing (NFO) strain XL4 to achieve efficient denitrification at low carbon-to-nitrogen (C/N) ratio. Results indicated that the denitrification efficiency increased from 65.47 to 97.99% at 24 h after co-culture at C/N of 1.0. Three-dimensional fluorescence excitation-emission matrix (3D-EEM) showed significant changes in the intensity of soluble microbial products (SMP), fulvic-like materials, and aromatic proteins after co-culture. Bio-precipitates were characterized by Scanning electron microscope (SEM), Fourier transform infrared spectrometer (FTIR), and X–ray diffraction (XRD), which showed that cellulose structure was disrupted and the metabolites were potential carbon source for denitrification. In addition, cellulase activity suggested that the hydrolysis of β-1,4-glycosidic bonds and oligosaccharides may be the rate-limiting steps in cellulose degradation. This work promoted the understanding of denitrification characteristics of co-culture and expanded the application of cellulose degrading bacteria in sewage treatment.
研究领域:
微生物学
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环境科学
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污水处理
✓ 已验证
DOI
PubMed
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 10
·1-10
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IF 4.3
Zhao Qiao,Wang Hongyu,Liang Haoting,Han Xiaoxue,Wei Chongyang,Wang Shiwei,Wang Yue,Huang Shouying,Ma Xinbin
Lower olefins, produced from syngas through Fischer-Tropsch synthesis, has been gaining worldwide attention as a non-petroleum route. However, the process demonstrates limited selectivity for target products. Herein, a hybrid catalyst system utilizing Fe-based catalyst and SAPO-34 was shown to enhance the selectivity toward lower olefins. A comprehensive study was conducted to examine the impact of various operating conditions on catalytic performance, such as space velocity, pressure, and temperature, as well as catalyst combinations, including loading pattern, and mass ratio of metal and zeolite. The findings indicated that the addition of SAPO-34 was beneficial for enhancing catalytic activity. Furthermore, compared with AlPO-34 zeolite, the strong-acid site on SAPO-34 was identified to crack the long-chain hydrocarbons, thus contributing to the lower olefin formation. Nevertheless, an excess of strong-acid sites was found to detrimentally impact the selectivity of lower olefins, attributed to the increased aromatization and polymerization of lower olefins. The detailed analysis of a hybrid catalyst in Fischer-Tropsch synthesis provides a practical strategy for improving lower olefins selectivity, and has broader implications for the application of hybrid catalyst in diverse catalytic systems.
研究领域:
化学工程
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催化科学
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
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2024
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IF 7.4
Chuanlin Hu,Yedongyang Liu,Xiong Qian,Yukun Qin,Yemin Dong,Fazhou Wang
The MgO production worldwide is mainly achieved through the calcination of magnesite in the wake of higher energy requirements. This study proposes an energy-saving calcination strategy through low-temperature partially calcining hydromagnesite (4MgCO 3 ·Mg(OH) 2 ·4H 2 O). Furthermore, the feasibility of using the partially calcined hydromagnesite and slag to produce a sustainable cementitious material was investigated by various techniques. This approach requires relatively low temperature and short processing time with a potential energy saving of production and CO 2 emission of fuel combustion. Moreover, it accelerates the hydration rate due to amorphous magnesium carbonate. Results indicated that the amorphous magnesium carbonate is formed during the partial calcination of hydromagnesite. It tends to transform to nesquehonite (MgCO 3 ·3H 2 O) in the initial stage of hydration, which is responsible for promoting early hydration and excellent early compressive strength. Finally, the reaction mechanism of the partially calcined hydromagnesite-based cementitious materials has been established, demonstrating its enormous potential for preparing low-carbon cementitious materials.
研究领域:
材料科学
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环境科学
✓ 已验证
DOI
高影响因子
Energies
·
2024
·Vol. 17
·期 3
·646
·
IF 3
Osama A. Marzouk
Recently, worldwide, the attention being paid to hydrogen and its derivatives as alternative carbon-free (or low-carbon) options for the electricity sector, the transport sector, and the industry sector has increased. Several projects in the field of low-emission hydrogen production (particularly electrolysis-based green hydrogen) have either been constructed or analyzed for their feasibility. Despite the great ambitions announced by some nations with respect to becoming hubs for hydrogen production and export, some quantification of the levels at which hydrogen and its derived products are expected to penetrate the global energy system and its various demand sectors would be useful in order to judge the practicality and likelihood of these ambitions and future targets. The current study aims to summarize some of the expectations of the level at which hydrogen and its derivatives could spread into the global economy, under two possible future scenarios. The first future scenario corresponds to a business-as-usual (BAU) pathway, where the world proceeds with the same existing policies and targets related to emissions and low-carbon energy transition. This forms a lower bound for the level of the role of hydrogen and its penetration into the global energy system. The second future scenario corresponds to an emission-conscious pathway, where governments cooperate to implement the changes necessary to decarbonize the economy by 2050 in order to achieve net-zero emissions of carbon dioxide (carbon neutrality), and thus limit the rise in the global mean surface temperature to 1.5 °C by 2100 (compared to pre-industrial periods). This forms an upper bound for the level of the role of hydrogen and its penetration into the global energy system. The study utilizes the latest release of the annual comprehensive report WEO (World Energy Outlook—edition year 2023, the 26th edition) of the IEA (International Energy Agency), as well as the latest release of the annual comprehensive report WETO (World Energy Transitions Outlook—edition year 2023, the third edition) of the IRENA (International Renewable Energy Agency). For the IEA-WEO report, the business-as-usual situation is STEPS (Stated “Energy” Policies Scenario), and the emissions-conscious situation is NZE (Net-Zero Emissions by 2050). For the IRENA-WETO report, the business-as-usual situation is the PES (Planned Energy Scenario), and the emissions-conscious situation is the 1.5°C scenario. Through the results presented here, it becomes possible to infer a realistic range for the production and utilization of hydrogen and its derivatives in 2030 and 2050. In addition, the study enables the divergence between the models used in WEO and WETO to be estimated, by identifying the different predictions for similar variables under similar conditions. The study covers miscellaneous variables related to energy and emissions other than hydrogen, which are helpful in establishing a good view of how the world may look in 2030 and 2050. Some barriers (such as the uncompetitive levelized cost of electrolysis-based green hydrogen) and drivers (such as the German H2Global initiative) for the hydrogen economy are also discussed. The study finds that the large-scale utilization of hydrogen or its derivatives as a source of energy is highly uncertain, and it may be reached slowly, given more than two decades to mature. Despite this, electrolysis-based green hydrogen is expected to dominate the global hydrogen economy, with the annual global production of electrolysis-based green hydrogen expected to increase from 0 million tonnes in 2021 to between 22 million tonnes and 327 million tonnes (with electrolyzer capacity exceeding 5 terawatts) in 2050, depending on the commitment of policymakers toward decarbonization and energy transitions.
研究领域:
能源研究
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环境科学
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政策分析
✓ 已验证
DOI
高影响因子
Journal of Cleaner Production
·
2025
·
IF 10
Xincheng Zhang,Juanjuan Yang,Changqing He,Ying Tian,Lin He,Hong Sui,Xingang Li
The economic and environmental treatment of oily sludges is always a challenge in industry. Herein, we propose an interfacial capture and demulsification hybrid process to deeply separate and recover the heavy oil (even over 97%) from the sludges with rejecting the encapsulated micro-/nano-mineral particles from the heavy oil phase in a low-carbon way (save energy over 69.3% compared with commercial pyrolysis). After testing over ten different oily sludges samples from petroleum industry, coal industry and steel industry, it is proved that this novel process possesses good universality, as well as high quality of products (oil, solids and water). A detailed mechanistic study by interfacial/surface characterizations approves the roles of interfacial capture of fine particles by dispersed water droplets and demulsification of asphaltenes-solids co-stabilized emulsions by a home-made oxygen-containing non-ionic demulsifier. Finally, a comprehensive evaluation has been made for this process, which demonstrates its excellent economy and environmental feasibility.
研究领域:
环境科学
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化学工程
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
APPLIED ORGANOMETALLIC CHEMISTRY
·
2024
·
IF 3.7
Yi Jing Jia,Jin Quan Tao,Hao Ran Liu,Wen Bin Huang,Rongpeng Yao,Miaomiao Niu,Rongrong Li,Qiang Wei,Ya Song Zhou
To enhance the CO 2 hydrogenation activity and low-carbon olefin selectivity of Fe-based catalysts, a strategy involving the use of metal promoters to modulate the structure of active metal centers in catalyst preparation was proposed. The incipient wetness impregnation method was used to introduce modifying agents K and/or Co into the Fe/Al 2 O 3 catalyst. Characterization techniques such as XRD, BET, SEM, HRTEM, H 2 -TPR, XPS, CO 2 -TPD, NH 3 -TPD, and TG were employed to investigate the effects of the modifying agents on the dispersion, reducibility, electronic properties, and acid–base properties of active metal species. Furthermore, the influence of K and Co modification on the CO 2 hydrogenation activity and low-carbon olefin selectivity of Fe/Al 2 O 3 catalysts was explored. The results revealed that the introduction of K generated more basic sites and electron-rich active metal centers in the catalyst, facilitating the adsorption and activation of CO 2 , while suppressing the hydrogenation of olefins and the formation of methane, thus improving the selectivity towards low-carbon olefins. Co promoter facilitated the dispersion of Fe species, exposing more active sites and enhancing the FTS reaction activity, leading to more CO being converted into C 2+ hydrocarbon products. Under the synergistic effect of K and Co, the CO 2 conversion activity of the Fe-based catalyst significantly increased, achieving a CO 2 conversion rate of 37%, while the selectivity towards C 2 -C 4= increased to 31.9%.
研究领域:
催化化学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOM
·
2024
·Vol. 76
·期 7
·3492-3503
·
IF 2.1
Wang Yaohuan,Zhang Fengxia,Hu Jianhang,Yang Shiliang,Liu Huili,Wang Hua
The recovery of valuable metals from copper slag (CS) is an effective way to realize its resource utilization. However, the use of fossil reductants in the reduction process can result in large amounts of carbon dioxide emissions. Therefore, a low-carbon method for recovering valuable metals from CS using castor oil as a green reductant is proposed in this study. The reduction behavior of CS is investigated through thermodynamic calculations, reduction experiments and thermogravimetric analysis. Under optimal experimental conditions, the recovery ratios of Fe and Cu reach 98.75% and 99.24%. The formed crude concentrate contains 94.27 wt.% Fe, 0.82 wt.% Cu and 0.042 wt.% S, which can partially replace the raw material in the production of weathering steel. Meanwhile, the waste residue produced can be used as the base material for glass-ceramics. The reduction characteristics of castor oil, CS and CaO blends are investigated based on thermogravimetric analysis, and the entire reduction process is divided into five stages. The activation energy of the reduction process is calculated using two iso-conversion methods, KAS and FWO. The reaction models for two reduction stages (stage IV and stage V) are determined using the Coats-Redfern method. The reaction model changes significantly with increasing temperature, shifting from a limiting surface reaction (R2) to a chemical reaction (C3). This study provides new insights into the resource utilization of CS and the development of low-carbon metallurgical technology.
研究领域:
冶金工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2025
·
IF 7.3
Yonghui Yang,Hengwei Yan,Zhanwei Liu,Shenghui Guo,Rui Xia,Jin Zhang
This study develops a two-step electrolysis process using TiO2 as the raw material for large-particle titanium powder production in fluoride-chloride molten salts. TiO2 is first dissolved in NaF-K2TiF6 molten salt at 850 °C to form Ti–O–F complexes, and then titanium is electrodeposited at 1.2 A/cm2 for 4 h to produce sponge-like titanium powder. The obtained titanium powder has an average particle size of approximately 30 μm and an oxygen content of about 0.59 wt %. Due to the high oxygen content, secondary electrorefining is performed in NaCl-KCl melts, investigating the effects of TiCl4 addition, current density, and Ti2+ ion concentration. Under conditions of 0.6 A/cm2 current density and 8 wt % Ti2+ ion concentration with TiCl4 addition, the titanium powder reaches an average particle size of 220 μm, with the oxygen content significantly reduced to 0.021 wt %, and its particle size increases significantly. The oxygen content decreases. The current efficiency during the electrolysis of TiO2 is 54%, while the current efficiency during the secondary electrorefining process is 72%. COMSOL Multiphysics simulation shows good agreement with experimental results, highlighting the influence of current density and titanium ion concentration on cathodic deposition thickness. Compared with the traditional Kroll process, this method reduces energy consumption by approximately 30%, offering a more sustainable and energy-efficient alternative for titanium production. This study confirms the feasibility of using TiO2 in fluoride-based molten salt systems for continuous titanium production.
研究领域:
材料科学
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冶金工程
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电化学
✓ 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）