Journal of the American Chemical Society
·
2024
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IF 14.4
Yao Song,Xiao Yang,Huan Liu,Suxia Liang,Yafeng Cai,Wenqiang Yang,Kaixin Zhu,Liang Yu,Xiaoju Cui,Dehui Deng
Electrochemical conversion of CH4 to easily transportable and value-added liquid fuels is highly attractive for energy-efficient CH4 utilization, but it is challenging due to the low reactivity and solubility of CH4 in the electrolyte. Herein, we report a high-pressure electro-Fenton (HPEF) strategy to establish a hetero-homogeneous process for the electrocatalytic conversion of CH4 by O2 at room temperature. In combination with elevation of reactant pressure to accelerate reaction kinetics, it delivers an unprecedented HCOOH productivity of 11.5 mmol h–1 gFe–1 with 220 times enhancement compared to that under ambient pressure. Remarkably, an HCOOH Faradic efficiency of 81.4% can be achieved with an ultralow cathodic overpotential of 0.38 V. The elevated pressure not only promotes the electrocatalytic reduction of O2 to H2O2 but also increases the reaction collision probability between CH4 and •OH, which is in situ generated from the Fe2+-facilitated decomposition of H2O2.
研究领域:
环境科学
·
电化学工程
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PubMed
高影响因子
FUEL
·
2019
·
IF 5.128
Yanlei Shang,Jinchun Shi,Hongbo Ning,Runtong Zhang,Hongyan Wang,Shengnian Luo
Ignition delay times for methane/nitromethane binary fuels with oxygen diluted in Ar ( CH 4 / CH 3 NO 2 / O 2 /Ar mixtures) are measured with a heated shock tube behind the reflected shock wave at 995–1962 K and 4–18 atm for different equivalence ratios (0.5, 1.0, and 2.0). Blending ratios for CH 3 NO 2 are varied (0, 0.1, 0.2, 0.5, and 1) to investigate the promotion of CH 3 NO 2 on CH 4 during the ignition process. OH ∗ emission histories at a sidewall are used to determine the measured ignition delay times of the binary fuels mixture. Correlations for the measured ignition delay times are obtained using multiple linear regression as a function of pressure, temperature, blending ratio, and equivalence ratio. Experimental results show that a small addition of CH 3 NO 2 dramatically reduces the ignition delay times of CH 4 , and induces a weak two-stage ignition. Three literature mechanisms are examined and compared with the measured ignition delay times for CH 4 / CH 3 NO 2 binary fuels mixtures, and the mechanism from Mathieu et al. is updated and validated against the experimental data. In this mechanism, the rate constants for some important reactions are theoretically determined by quantum chemical calculation. In addition, sensitivity analysis and reaction pathway analysis as well as rate of production are carried out to further elucidate the promotion of CH 3 NO 2 on ignition of the CH 4 .
研究领域:
化学动力学
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燃烧科学
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物理化学
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高影响因子
Molecular Catalysis
·
2023
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IF 4.6
Zhishuai Wang,Fengyun Su,Hailong Cao,Mengzhen Tian,Xiang Li,Haiquan Xie,Xiaoli Jin,Zhengdao Li,Xin Ying Kong
Amidst the impending energy crisis and escalating concerns about global warming, photocatalytic reduction of carbon dioxide (CO 2 ) emerges as a promising solution. However, the practical application of this technology has been hindered by challenges such as the poor photoresponse of existing photocatalysts toward visible light, inefficient separation efficiency of photoinduced electron-hole pairs, and subpar product selectivity. This work simultaneously addresses these limitations by enhancing the activity of photocatalytic CO 2 reduction through the strategic incorporation of nickel oxide (NiO) onto niobium pentoxide (Nb 2 O 5 ). In this study, Nb 2 O 5 was prepared using the hydrothermal and calcination methods, culminating in the synthesis of NiO-supported Nb 2 O 5 achieved through the photodeposition method. The resulting 2 %-NIONBO photocatalyst with the optimal loading of NiO exhibited a remarkable methane (CH 4 ) production yield of 29.65 μmol/g/h, a striking 6.2-fold improvement over solitary NBO. In addition, the useful carbon monoxide (CO) fuel was also detected from the photoreduction of CO 2 , where 2 %-NIONBO exhibited a CO yield of 7.22 μmol/g/h, demonstrating a 3.4-fold enhancement over NBO, along with an outstanding CH 4 selectivity of 80.42 %. This study provides insights into the design and development of Nb-based photocatalysts for significantly enhanced efficiency in photocatalytic CO 2 reduction, paving the way for advancements in sustainable energy solutions and addressing environmental issues.
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高影响因子
Journal of Environmental Chemical Engineering
·
2022
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IF 7.968
Tangtong Ju,Yue Dai,Hailong Tang,Meiling Wang,Xiao Sun,Min Wang,Yongqing Ma,Ganhong Zheng
Direct conversion of CH 4 to high valued chemicals under mild conditions is attractive but full of challenges. Here, we present a ternary composite that consists of Ni-doped TiO 2 nanocubes (NCs) and CNTs as a new kind of catalyst (denoted as CNTs-Ni@TiO 2 NCs) for CH 4 photocatalytic conversion to C1 oxygenated products at 30 °C. Using H 2 O 2 as an oxidant, a high C1 oxygenated products yield and selectivity of 1.43 mol/(mol Ni ·h) and 95.6% can be reached in 2 h at 30 °C. The superior photocatalytic performance resulted from the synergistic effects of TiO 2 NCs, Ni species, and CNTs such as enhanced visible light absorption , improved electron/hole separation and charge transfer property, and lowered C-H bond cleavage energy required for CH 4 activation, were carefully studied. Good reusability of the catalyst was studied by recycle experiments. Possible reaction mechanism based on the radical routes were carefully discussed by combining in-situ Fourier transform infrared spectroscopy , X-ray photoelectron spectroscopy, electron spin resonance spectroscopy, radical scavenger experiments and density functional theory calculation.
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高影响因子
ACS Omega
·
2020
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IF 2.87
Jianbo Zhao,Jun Wei,Di Cai,Hui Cao,Tianwei Tan
A poly(amino acid)-based approach for scalable synthesis of micro-/mesoporous carbon (PC) with high specific surface area and narrow distribution of micro- and mesopores is presented. Using cross-linked poly aspartic acid as a precursor, PC was obtained by in situ one-step carbonization without the activating agent. The resulting PC had an ultrahigh adsorption capacity for H2 (4.43 wt %) and CH4 (4.49 mmol g–1). This novel method could significantly decrease the wastewater hazards caused by washout of the considerable amount of the activating agent. The PC showed promising application in gas adsorption and storage.
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DOI
PubMed
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Zheyuan Guo,Zihan Qu,Hong Wu,Rui Zhao,Yingzhen Wu,Yutao Liu,Leixin Yang,Yanxiong Ren,Chumei Ye,Zhongyi Jiang
Well-connected transport pathways play a critical role in high-performance CO2-facilitated separation membranes. Inspired by the ionic cluster network in polymer electrolyte membranes (PEMs) for fast ion transport, designing a unique CO2-philic cluster network structure is a promising strategy to construct efficient CO2 transport channels in membranes. Herein, a forced induction method is presented to construct a CO2-philic cluster network in membranes. Sulfobutylether-beta-cyclodextrin (sβ-CD) is introduced in a quaternary ammonium polysulfone (QAPSf) matrix. During the membrane formation process, the quaternary ammonium groups on QAPSf are attracted by the sulfonic acid groups on sβ-CD, assembling around and thus forming hybrid clusters. These clusters are swollen and interconnected by water under a humidified state. The hybrid cluster network acts as an effective CO2 transport pathway via clustering quaternary ammonium ion pairs as continuous CO2-facilitated transport sites. Simultaneously, the internal cavity of sβ-CD in hybrid clusters affords additional free volume in membranes, thus enhancing the CO2 permeability. The resultant QAPSf/sβ-CD membrane exhibits an optimal CO2 permeability of 1303 Barrer, a CO2/CH4 selectivity of 39, and good long-term operation stability for 30 days, surpassing the 2008 Robeson upper bound limit. This concept of constructing a hybrid cluster network for facilitated transport is expected to be applicable to explore more advanced PEMs for effective gas separation.
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高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2024
·Vol. 141
·期 16
·e55253
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IF 2.7
Xiaocan Zhang,Siqin Zeng,Jiashu Long,Xuesong Li,Yutong Zhao
Using porous materials to selectively adsorb H 2 O from natural gas is a promising method to dehydrate methane (CH 4 ). The structure of a Zirconium metal-organic framework (Zr-MOF), namely, MIP-202, features a high density of amino groups, which can produce strong hydrogen bonding with H 2 O molecules. MIP-202 is cost-effective, green and scalable, and it exhibits good chemical stability under various conditions. This work incorporated MIP-202 nanoparticles into the high permeability polymer polyetherimide (PEI), and the obtained Mixed Matrix Membranes (MMMs) was used for the gas separation of H 2 O/CH 4 . It is found that MMMs loaded with 20 wt% of MIP-202 demonstrated a high H 2 O/CH 4 selectivity of 832.2, which was about 760 times of that of the pure PEI. This approach offers a new route to fabricate functional membranes for energy-efficient gas separations.
研究领域:
材料科学
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环境工程
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化学工程
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高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2019
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IF 3.372
Zihan Qu,Hong Wu,Yue Zhou,Leixin Yang,Xingyu Wu,Yingzhen Wu,Yanxiong Ren,Ning Zhang,Yutao Liu,Zhongyi Jiang
Membranes with fast CO 2 transport pathways have attracted intense attention due to their outstanding CO 2 permeability, showing potential for industrial application. Regulating the spatial distribution of CO 2 -philic groups in polymer-based membranes is expected to be a promising strategy to achieve the fast CO 2 transport pathways. In membrane matrix, the interconnected network of concentrated domains of CO 2 facilitated transport groups provides membranes with specific CO 2 transport pathways and finally leads to their high separation performance. In this study, a novel kind of polyelectrolyte membrane, quaternary ammonium polysulfone with interconnected ionic clusters, is prepared to enhance the CO 2 permeability. The hydrophilic quaternary ammonium groups tend to aggregate spontaneously to create ionic clusters. Furthermore, under humidified conditions, these ionic clusters are connected by water to form an ionic cluster network in the membrane matrix. The ionic cluster network plays the crucial role in accelerating the selective transport for CO 2 molecules over CH 4 by the reversible interaction between CO 2 and ion pairs. By tuning the quaternization degree of polysulfone, a series of polyelectrolyte membranes with different size of ionic clusters were developed. Membranes with hydrated ionic clusters (5–9 nm) show dramatic enhancement in CO 2 separation performance, especially in CO 2 permeability. The as-prepared quaternary ammonium polysulfone membrane with 8.98 nm ionic clusters exhibited the high CO 2 permeability of 1109.44 Barrer and a high CO 2 /CH 4 selectivity of 29.70, which exceeds 2008 Robeson upper bound limit. The optimized separation performance of QA-PSf membranes is attractive for potential application such as CO 2 capture from flue gas and natural gas.
研究领域:
材料科学
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化学工程
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2025
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IF 13.2
Yingdong Hao,Yingxiao Wang,Pengyu Chen,Lu Chen,Wei Wei,Nannan Sun
Photocatalytic oxidation of methane (CH 4 ) to value-added chemicals offers a sustainable and promising approach for chemical synthesis, however, efficient catalysts for the activation of inert C H bonds remain challenging. Herein, a novel Ag-AgCl biphasic composite was used as co-catalysts to modify ZnO semiconductor (Ag-AgCl/ZnO-z). Structure properties and catalytic performance in photocatalytic oxidation of CH 4 of the sample were systematically investigated, together with comparison with pure ZnO (ZnO-z) and a single Ag modified counterpart (Ag/ZnO-z). It was found that Ag-AgCl/ZnO-z was enriched with heterogeneous interfaces, which facilitated ultrafast carrier transport and their prolonged separation. Interestingly, AgCl acted as a hole acceptor, and the lattice Cl can be directly activated to •Cl, which is then responsible for forming a new •CH 3 formation pathway via a hydrogen atom transfer (HAT) mechanism. Moreover, a Cl-looping process can be established so that the catalyst remained stable during cyclic reactions. Under the optimum conditions, an excellent liquid oxygenates productivity of 12,731 μmol·g −1 ·h −1 was achieved. This work presents a prototype for designing biphasic composite co-catalysts, thereby offering valuable insights into introducing multiple CH 4 activation pathways.
研究领域:
光催化
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材料科学
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化学合成
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能量转换
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环境化学
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DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2025
·Vol. 14
·期 1
·120640
·
IF 7.2
Yifan Wang,Zeliang Xiong,Shilin Xu,Yuan Gao,Haoli Zhou,Wanqin Jin
Polyimides with intrinsic microporosity are promising materials for gas separation, but their industrial application is hindered by poor long-term stability. This study proposes diamine modification of a polyimide membrane with diamines, such as p-phenylenediamine (p-PD), to enhance both membrane stability and selectivity for separating gas pairs such as CO 2 /CH 4 . Various characterization techniques confirmed the crosslinking reaction between the diamine and imide groups, which restricted the movement or rearrangement of polymer chains, resulting in improved membrane anti-plasticization performance and stability. Meanwhile, CO 2 -philic emeraldine base and quinone structures were formed due to the in-situ oxidation of p-PD during the crosslinking process, which significantly boosted CO 2 /CH 4 selectivity. The maximum selectivity (44.5), which is 66.0 % higher than that of the pristine membrane, was achieved using a p-PD-modified polyimide membrane for the separation of pure single CO 2 /CH 4 . Additionally, the separation of other gas pairs (such as CO 2 /N 2 ) and the effect of pressure on the separation of a CO 2 /CH 4 mixture were investigated using the p-PD-modified polyimide membrane, which demonstrated improved performance. Thus, this study provides a reference for enhancing the selectivity and stability of polyimide membranes through diamine modification using p-PD and its analogues.
研究领域:
材料科学
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膜技术
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气体分离
·
高分子化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2026
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IF 9
Nan Li,Weijie Liu,Liying Liu,Peng Gao,Xiaojing Di,Gang Kevin Li
Methane is the second most significant greenhouse gas after carbon dioxide, and the development of efficient methane/nitrogen separation materials is crucial for recovering methane from low-concentration anthropogenic sources. In this study, a novel adsorbent, CHY, was developed using binder-free Y zeolite (BF-Y-Z) as the precursor, modified by incorporating CH + ions through ion exchange. Characterization results confirmed the successful introduction of CH + ions without altering the zeolite's FAU-type framework structure. The adsorption performance of CHY was systematically evaluated, demonstrating good CH 4 uptake and CH 4 /N 2 separation capability. According to IAST model calculations, CHY exhibited a CH 4 /N 2 selectivity of 4.1 at 303 K and 100 kPa, which represents a significant improvement over the unmodified BF-Y-Z. A single-column breakthrough experiment revealed a dynamic CH 4 adsorption capacity of 0.21 mmol/g at 303 K, indicating CHY's effective CH 4 capture performance in flowing binary gas systems. A four-column vacuum swing adsorption (VSA) cycle was established to investigate the influence of gas flow rate, adsorption time, and desorption time on methane purity and recovery. Under optimal conditions (gas flow rate of 0.4 L/min, adsorption time of 100 s, and desorption time of 120 s), CHY achieved a methane purity of 65% and a recovery rate of 75%. These results highlight CHY's excellent separation efficiency and cyclic stability, suggesting its strong potential for practical methane/nitrogen separation applications.
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高影响因子
ADSORPTION SCIENCE & TECHNOLOGY
·
2014
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IF 0.93
Qiaobei Dong,Wei Su,Xiuwu Liu,Jia Liu,Yan Sun
A method to separate a gaseous mixture of nitrogen and methane by exploiting the difference between hydrate-formation pressures of nitrogen and methane has been developed to enrich the concentration of methane in low-quality coal-bed methane. The equilibrium isotherms of pure N2 and CH4 in CMK-3, a mesoporous carbon material, in the presence of water are measured to determine the optimal separation parameters. Tetrahydrofuran (THF) was added to the water to lower the pressures at which the gas hydrates are formed. A gaseous mixture containing 50% methane was fed through a bed filled with CMK-3 in which a THF solution of 5 mmol/g was pre-adsorbed. The final methane concentration was higher than 70% at 275.15 K.
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DOI
高影响因子
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