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Effect of valence and spin state on ethane dehydrogenation in Fe-S-1 catalyst
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作者 Liusai Huang Yumeng Fo +6 位作者 Peng Zhang Shaojia Song Xinxin Zhang Xueqiu Wu Saeed Soltanali Jian Liu Weiyu Song 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第10期677-686,I0014,共11页
Light alkanes non-oxidative dehydrogenation is an attractive non-oil route for olefins production.The alkane dehydrogenation reaction is limited by thermodynamic equilibrium,and the C-H bond cleavage is commonly consi... Light alkanes non-oxidative dehydrogenation is an attractive non-oil route for olefins production.The alkane dehydrogenation reaction is limited by thermodynamic equilibrium,and the C-H bond cleavage is commonly considered as the rate-determined step.The valence state of metal sites in catalysts will influence the stabilization of the vital intermediate(i.e.,C_(x)H_(y)...M^(δ+)...H)during the C-H bond cleavage process,which in turn affects the catalytic reactivity.Herein,we explicitly investigated the effect of different valence states of framework-Fe in silicate-1 zeolite on ethane dehydrogenation reaction through the combination of experimental and theoretical study.Fe(Ⅱ)-S-1 and Fe(Ⅲ)-S-1 catalysts are successfully synthesized by ligand-assisted in situ crystallization method,In-situ C_(2)H_6-FTIR shows the higher coverage of hydrocarbon intermediates on Fe(Ⅱ)-S-1,Under the same evaluation co nditio n,Fe(Ⅱ)-S-1 exhibits a higher space time yield of ethylene.Density functional theory(DFT)results reveal that the more coordinate-unsaturated and electron-enriched Fe(Ⅱ)sites boost the first C-H bond activation by slight deformation and efficient electron donation with C_(2)H_(5)^(*)species.Remarkably,the second C-H bond cleavage on Fe(Ⅱ)-S-1 undergoes a spin-crossing process from quintet state to triplet state,which involves a two-electro n-two-orbital interaction,further promoting the formation of ethylene.Microkinetic analysis is consistent with the experimental and DFT results.This work could provide methodology for elucidating the effect of metal valence states on catalytic performance as well as offer guidance for designing more efficient Fe-zeolite catalysts. 展开更多
关键词 IRON ethane dehydrogenation Electron-enriched Spin crossover DFT
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Mn-doped SrCoO_(3-δ) Perovskite Oxides for Ethylene Production via Chemical Looping Oxidative Dehydrogenation of Ethane
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作者 Li Zhi Liu Linjiao +4 位作者 Hao Daijun Ren Xiaohang Shen Fangxia Li Xin Yu Anping 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期53-62,共10页
Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers.... Chemical looping oxidative dehydrogenation (CL-ODH) is an economically promising method for convertingethane into higher value-added ethylene utilizing lattice oxygen in redox catalysts, also known as oxygen carriers. Inthis study, perovskite-type oxide SrCoO_(3-δ) and B-site Mn ion-doped oxygen carriers (SrCo_(1-x)MnxO_(3-δ), x=0.1, 0.2, 0.3)were prepared and tested for the CL-ODH of ethane. The oxygen-deficient perovskite SrCoO_(3-δ) exhibited high ethyleneselectivity of up to 96.7% due to its unique oxygen vacancies and lattice oxygen migration rates. However, its low ethyleneyield limits its application in the CL-ODH of ethane. Mn doping promoted the reducibility of SrCoO_(3-δ) oxygen carriers,thereby improving ethane conversion and ethylene yield, as demonstrated by characterization and evaluation experiments.X-ray diffraction results confirmed the doping of Mn into the lattice of SrCoO_(3-δ), while X-ray photoelectron spectroscopy(XPS) indicated an increase in lattice oxygen ratio upon incorporation of Mn into the SrCoO_(3-δ) lattice. Additionally, H2temperature-programmed reduction (H2-TPR) tests revealed more peaks at lower temperature reduction zones and a declinein peak positions at higher temperatures. Among the four tested oxygen carriers, SrCo0.8Mn0.2O_(3-δ) exhibited satisfactoryperformance with an ethylene yield of 50% at 710 °C and good stability over 20 redox cycles. The synergistic effect of Mnplays a key role in increasing ethylene yields of SrCoO_(3-δ) oxygen carriers. Accordingly, SrCo0.8Mn0.2O_(3-δ) shows promisingpotential for the efficient production of ethylene from ethane via CL-ODH. 展开更多
关键词 ethane ETHYLENE PEROVSKITE chemical looping oxidative dehydrogenation
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Ethane Chemical Looping Oxidative Dehydrogenation to Ethylene over Co_(2)O_(3)(Fe_(2)O_(3),NiO)/LaCoO_(3) Oxygen Carriers
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作者 Liang Hao Meng Jinhong +1 位作者 Sun Jie Wei Dongkai 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期33-41,共9页
Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for converting ethane to ethylene.In the current study MeO/LaCoO_(3)(MeO=Fe_(2)O_(3),NiO or Co_(2)O_(3))composite metal oxides w... Ethane chemical looping oxidative dehydrogenation(CL-ODH)to ethylene is a new technology for converting ethane to ethylene.In the current study MeO/LaCoO_(3)(MeO=Fe_(2)O_(3),NiO or Co_(2)O_(3))composite metal oxides were prepared via citrate gel and impregnation methods,and used as oxygen carriers for CL-ODH.X-ray diffraction results indicated that all oxygen carriers had a perovskite structure even after eight redox cycles.Under a reaction temperature of 650°C,a reaction pressure of 0.1 MPa,and a weight hourly space velocity(WHSV)of 7500 mL/(g·h),ethane conversion over Co_(2)O_(3)/LaCoO_(3) reached 100%and ethylene selectivity reached 60%,both of which were better than corresponding values attained over Fe_(2)O_(3)/LaCoO_(3) and NiO/LaCoO_(3).Ethylene selectivity remained stable for 80 cycles over Co_(2)O_(3)/LaCoO_(3),then decreased gradually after 80 cycles.X-ray photoelectron spectroscopy results and evaluation results indicated that lattice oxygen and O_(2)2-had a direct relationship with ethane conversion and ethylene selectivity.Co_(2)O_(3)/LaCoO_(3) exhibited a strong capacity to release and absorb oxygen,mainly due to interaction between Co_(2)O_(3) and LaCoO_(3). 展开更多
关键词 chemical looping oxidative dehydrogenation ethane ETHYLENE oxygen carrier PEROVSKITE
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Ab initio molecular dynamics simulation reveals the influence of entropy effect on Co@BEA zeolite-catalyzed dehydrogenation of ethane
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作者 Yumeng Fo Shaojia Song +8 位作者 Kun Yang Xiangyang Ji Luyuan Yang Liusai Huang Xinyu Chen Xueqiu Wu Jian Liu Zhen Zhao Weiyu Song 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第10期195-205,共11页
The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulati... The C–H bond activation in alkane dehydrogenation reactions is a key step in determining the reaction rate.To understand the impact of entropy,we performed ab initio static and molecular dynamics free energy simulations of ethane dehydrogenation over Co@BEA zeolite at different temperatures.AIMD simulations showed that a sharp decrease in free energy barrier as temperature increased.Our analysis of the temperature dependence of activation free energies uncovered an unusual entropic effect accompanying the reaction.The unique spatial structures around the Co active site at different temperatures influenced both the extent of charge transfer in the transition state and the arrangement of 3d orbital energy levels.We provided explanations consistent with the principles of thermodynamics and statistical physics.The insights gained at the atomic level have offered a fresh interpretation of the intricate long-range interplay between local chemical reactions and extensive chemical environments. 展开更多
关键词 ethane dehydrogenation C-H bond activation Ab initio molecular dynamics simulation ENTROPY Heterogeneous catalysis
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Ca_(2)MnO_(4)-layered perovskite modified by NaNO_(3)for chemical-looping oxidative dehydrogenation of ethane to ethylene
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作者 Weixiao Ding Kun Zhao +2 位作者 Shican Jiang Zhen Huang Fang He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期53-64,共12页
Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the... Chemical-looping oxidative dehydrogenation(CL-ODH)is a process designed for the conversion of alkanes into olefins through cyclic redox reactions,eliminating the need for gaseous O_(2).In this work,we investigated the use of Ca_(2)MnO_(4)-layered perovskites modified with NaNO_(3) dopants,serving as redox catalysts(also known as oxygen carriers),for the CL-ODH of ethane within a temperature range of 700-780℃.Our findings revealed that the incorporation of NaNO_(3) as a modifier significantly-nhanced the selectivity for-thylene generation from Ca_(2)MnO_(4).At 750℃and a gas hourly space velocity of 1300 h^(-1),we achieved an-thane conversion up to 68.17%,accompanied by a corresponding-thylene yield of 57.39%.X-ray photoelectron spectroscopy analysis unveiled that the doping NaNO_(3) onto Ca_(2)MnO_(4) not only played a role in reducing the oxidation state of Mn ions but also increased the lattice oxygen content of the redox catalyst.Furthermore,formation of NaNO_(3) shell on the surface of Ca_(2)MnO_(4) led to a reduction in the concentration of manganese sites and modulated the oxygen-releasing behavior in a step-wise manner.This modulation contributed significantly to the enhanced selectivity for ethylene of the NaNO_(3)-doped Ca_(2)MnO_(4) catalyst.These findings provide compelling evidence for the potential of Ca_(2)MnO_(4)-layered perovskites as promising redox catalysts in the context of CL-ODH reactions. 展开更多
关键词 Chemical-looping oxidative DEHYDROGENATION ethane ETHYLENE NaNO_(3)-doped Ca_(2)MnO_(4)redox catalyst Layered perovskites
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Complexation Properties and Synthesis of 1,2-Bis(2 ,2' -bipyridinyl)ethylene and 1,2-Bis(2,2' -bipyridinyl)ethane Ligands with Cu(I)
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作者 He Yongbing and Lehn Jean-Marie (Institut Le Bel,Universite Louis Pasleur, A, rue Blaise Pascal, 67000 Strasbourg, France) Department of Chemistry, Wuhan University, Wuhan. 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1990年第3期183-187,共5页
l,2-Bis(2,2'-bipyridinyl)ethylene(1) ligand was synthesized by Wittig-Horner reaction and 1, 2-Bis(2, 2'-bipyridinyl)ethane(2) ligand(which can be obtained via another route ) was prepared by hydrogenation of ... l,2-Bis(2,2'-bipyridinyl)ethylene(1) ligand was synthesized by Wittig-Horner reaction and 1, 2-Bis(2, 2'-bipyridinyl)ethane(2) ligand(which can be obtained via another route ) was prepared by hydrogenation of (1). The formation of complexes of (1) and (2) with copper (I) has been studied. The influence of the different bridge chains (CH =CH, CH2CH2) on complexation is discussed on the basis of 1H NMR spectra. Keywords Dipyridine aldehyde, Dipyridine derivative, Copper complex 展开更多
关键词 BP Complexation Properties and Synthesis of 1 2-Bis bipyridinyl)ethylene and 1 2-Bis bipyridinyl)ethane Ligands with Cu
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Octa-membered Water Ring Chain Based on Sulfonic Group in Ni(II) Complex with 2-[(E)-(2-Oxidophenyl)methyleneamino] Ethanesulfonato and 2,2′-Bipyridinyl 被引量:2
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作者 张淑华 李光照 +1 位作者 钟凡 冯小珍 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1491-1494,共4页
The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983... The title compound, [Ni(tssb)(2,2-bipy)2].5(H2O) 1 (tssbH2 =2-[(E)-(2-oxido- phenyl)methyleneamino]ethanesulfonato, 2,2-bipy = 2,2'-bipyridinyl), belongs to orthorhombic, space group Pbcn with a = 20.3983(18), b = 17.6929(15), c = 17.0897(15) nm, V= 6167.8(9) nm^3, Mr= 688.38, Z = 8, De = 1.481 g.cm^-3, F(000) = 2880,μ = 0.758 mm-1 and S =1.099. Each NiIr atom is six-coordinated by one N and one O atoms from one tssb^2- anion and four N atoms from two 2,2-bipy ligands to give a distorted octahedral geometry. Noticeably, there exists a rare octa-mem- bered water ring which presents a 1D chain by sulfonic group. 展开更多
关键词 II Octa-membered Water Ring Chain Based on Sulfonic Group in Ni bipyridinyl Complex with 2 ethanesulfonato and 2 2 Oxidophenyl)methyleneamino
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Adsorption dynamics of ethane from air in structured fixed beds with different microfibrous composites
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作者 Huan Xiang Huiping Zhang +1 位作者 Pengfei Liu Ying Yan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第1期14-24,共11页
Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied.5A zeolite membrane 5A/PSSF(paper-like sintered stainless steel fiber)and microfibrous entrap... Adsorption dynamics of ethane in two granular fixed beds and structured fixed beds with microfibrous composites was studied.5A zeolite membrane 5A/PSSF(paper-like sintered stainless steel fiber)and microfibrous entrapped activated carbon(MEAC)composites were prepared by wet layup papermaking/sintering technique and in-situ hydrothermal method.Microfibrous composites were characterized by X-ray diffraction,scanning electron microscopy and N2 adsorption/desorption.Structured fixed beds were designed by filling granular adsorbents(5A zeolite or activated carbon)and microfibrous composites at the inlet and outlet of the beds,respectively.Effects of flow rate,bed height and structure on the breakthrough curves were investigated.The length of unused bed(LUB)was determined,and Yoon–Nelson model was used to fit the breakthrough curves.The experimental results showed ethane was effectively adsorbed on the granular adsorbents and microfibrous composites.Both composites could decrease the LUB values and enhance bed utilization.All breakthrough curves fitted well to Yoon–Nelson model,with correlation coefficient exceeding 0.89.The adsorption rate of ethane could be improved in the structured fixed beds,which showed an enhanced mass transfer efficiency for ethane adsorption.LUB values of structured fixed beds with 5A/PSSF composites were larger,the bed utilization values were lower,and the adsorption rate constants were higher than those with MEAC composites under the same conditions. 展开更多
关键词 5A zeolite membrane Microfibrous entrapped activated carbon ethane Structured fixed bed Adsorption dynamics
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Plasma treated M1 MoVNbTeO_(x)-CeO_(2) composite catalyst for improved performance of oxidative dehydrogenation of ethane
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作者 Shuairen Qian Yuxin Chen +1 位作者 Binhang Yan Yi Cheng 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第3期904-914,共11页
High activity and productivity of MoVNbTeO_(x) catalyst are challenging tasks in oxidative dehydrogenation of ethane(ODHE)for industrial application.In this work,phase-pure M1 with 30 wt%CeO_(2) composite catalyst was... High activity and productivity of MoVNbTeO_(x) catalyst are challenging tasks in oxidative dehydrogenation of ethane(ODHE)for industrial application.In this work,phase-pure M1 with 30 wt%CeO_(2) composite catalyst was treated by oxygen plasma to further enhance catalyst performance.The results show that the oxygen vacancies generated by the solid-state redox reaction between M1 and CeO_(2) capture active oxygen species in gas and transform V^(4+)to V^(5+)without damage to M1 structure.The space-time yield of ethylene of the plasma-treated catalyst was significantly increased,in which the catalyst shows an enhancement near~100% than that of phase-pure M1 at 400℃ for ODHE process.Plasma treatment for catalysts demonstrates an effective way to convert electrical energy into chemical energy in catalyst materials.Energy conversion is achieved by using the catalyst as a medium. 展开更多
关键词 Oxidative dehydrogenation of ethane(ODHE) MoVNbTeO_(x) Composite catalyst Oxygen plasma Energy conversion
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乙烷-丙烷混合裂解不同维度的数值模拟
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作者 李金莲 刘鸿艳 +3 位作者 吴红军 李金山 张永军 张红梅 《化学世界》 2024年第1期14-20,共7页
随着乙烯原料向着轻质化发展,乙烷、丙烷成为重要的裂解原料,乙烷-丙烷混合裂解自由基反应机理的研究对乙烯原料优化具有重要意义。利用FLUENT模拟软件对乙烷-丙烷混合裂解自由基反应机理进行一维和二维模拟,根据一维、二维模型轴向和... 随着乙烯原料向着轻质化发展,乙烷、丙烷成为重要的裂解原料,乙烷-丙烷混合裂解自由基反应机理的研究对乙烯原料优化具有重要意义。利用FLUENT模拟软件对乙烷-丙烷混合裂解自由基反应机理进行一维和二维模拟,根据一维、二维模型轴向和径向的流速、温度、原料及产物浓度分布,分析其混合裂解规律。径向的传递过程会降低裂解温度,所需供热量减少,同时径向自由基的返混促进了管中心原料的裂解,因此二维模型中乙烯和甲烷的浓度高于一维模型。乙烷-丙烷混合裂解的链引发阶段只有丙烷参与,乙烷参与了链传递过程,反应体系内自由基需要一定量的积累后才生成乙烯和丙烯。 展开更多
关键词 乙烷 丙烷 混合裂解 自由基反应机理 数值模拟
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中高压贫气乙烷回收流程分析及优选
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作者 蒋洪 黄小龙 +1 位作者 高鹏 陈泳村 《现代化工》 CAS CSCD 北大核心 2024年第5期228-232,238,共6页
为解决中高压贫气乙烷回收流程中能耗高及设备利用率低带来的经济损失问题,对3种高效乙烷回收流程(部分气体循环流程RSV、带压缩的强精馏流程SRC、冷干气回流流程CRR)进行能耗、以及经济分析对比,选出最佳流程为SRC。在保证乙烷回收率在... 为解决中高压贫气乙烷回收流程中能耗高及设备利用率低带来的经济损失问题,对3种高效乙烷回收流程(部分气体循环流程RSV、带压缩的强精馏流程SRC、冷干气回流流程CRR)进行能耗、以及经济分析对比,选出最佳流程为SRC。在保证乙烷回收率在95%以上的条件下,利用HYSYS软件模拟计算。能耗分析表明,SRC流程能耗最低,比RSV和CRR分别低10.17%、2.25%。分析表明,主体工艺中SRC流程总损最小,比RSV和CRR分别低63.51%、11.73%。经济分析表明,SRC流程年消耗经济成本最低,年总经济效益最好,比RSV和CRR分别高4.98%、13.24%。 展开更多
关键词 乙烷回收 能耗分析 (火用)分析 经济分析
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氮气双膨胀制冷提氦联产乙烷工艺设计与优化
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作者 马国光 周明杰 +2 位作者 雷洋 刘璐 邓昊天 《低碳化学与化工》 CAS 北大核心 2024年第10期110-118,共9页
国内某气田天然气中乙烷和氦气含量(物质的量分数)逐年升高,回收价值凸显。提出了一种氮气双膨胀制冷提氦联产乙烷工艺,采用HYSYS软件对该工艺进行了流程模拟,并对工艺流程的关键参数(低温分离器温度、脱甲烷塔塔顶回流比、二级提氦塔... 国内某气田天然气中乙烷和氦气含量(物质的量分数)逐年升高,回收价值凸显。提出了一种氮气双膨胀制冷提氦联产乙烷工艺,采用HYSYS软件对该工艺进行了流程模拟,并对工艺流程的关键参数(低温分离器温度、脱甲烷塔塔顶回流比、二级提氦塔进料温度、二级提氦塔塔顶回流比、氮气膨胀端入口压力、氮气膨胀端出口压力和氮气制冷剂流量)对工艺指标的影响规律开展了研究。基于最优化理论,以C_(2)收率最大和二次粗氦浓度最大时装置总能耗最小为目标,采用Back Propagation(BP)神经网络算法对关键参数进行了寻优。结果表明,装置总能耗主要受低温分离器温度、氮气膨胀端出口压力和氮气制冷剂流量影响,C_(2)收率主要受低温分离器温度和脱甲烷塔塔顶回流比影响,氦收率主要受二级提氦塔进料温度影响。关键参数最佳组合为:低温分离器温度为-95.30℃,氮气制冷剂流量为1549.22 kmol/h,氮气膨胀端入口压力为3.25 MPa,氮气膨胀端出口压力为0.44 MPa,脱甲烷塔塔顶回流比为0.13,二级提氦塔进料温度为-150.57℃,二级提氦塔塔顶回流比为0.80。相比于优化前,优化后装置总能耗降低了1.46%,C_(2)收率提升了5.64%,二次粗氦浓度(物质的量分数)提升了1.81%。 展开更多
关键词 氮气双膨胀制冷 天然气提氦 乙烷回收 联产工艺 参数优化 BP神经网络算法
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Selective oxidative dehydrogenation of ethane to ethylene over a hydroxylated boron nitride catalyst 被引量:11
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作者 石磊 闫冰 +3 位作者 邵丹 姜凡 王东琪 陆安慧 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2017年第2期389-395,共7页
Boron nitride containing hydroxyl groups efficiently catalysed oxidative dehydrogenation of ethane to ethylene,offering rather high selectivity(95%) but only small amount of CO2 formation(0.4%) at a given ethane c... Boron nitride containing hydroxyl groups efficiently catalysed oxidative dehydrogenation of ethane to ethylene,offering rather high selectivity(95%) but only small amount of CO2 formation(0.4%) at a given ethane conversion of 11%.Even at high conversion level of 63%,the selectivity of ethylene retained at 80%,which is competitive with the energy-demanding industrialized steam cracking route.A long-term test for 200 h resulted in stable conversion and product selectivity,showing the excellent catalytic stability.Both experimental and computational studies have identified that the hydrogen abstraction of B-OH groups by molecular oxygen dynamically generated the active sites and triggered ethane dehydrogenation. 展开更多
关键词 Boron nitride HYDROXYLATION ethane Oxidative dehydrogenation ETHYLENE
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MgX_(2)O_(4)(X=Cr、Fe、Mn)型尖晶石B位点阳离子对乙烷化学链氧化脱氢生成乙烯的影响 被引量:1
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作者 梁晓岑 王雪梅 +7 位作者 幸子凡 毛敏 宋达 李杨 龙涛 周宇超 陈佩丽 何方 《燃料化学学报(中英文)》 EI CAS CSCD 北大核心 2024年第7期1006-1019,共14页
化学链循环氧化脱氢技术(CL-ODH)是一个多功能的平台,它可以利用载氧体中晶格氧的选择性氧化这一特性,实现乙烷向乙烯的高值化转化。本研究探讨了MgX_(2)O_(4)(X=Cr、Fe或Mn)型尖晶石载氧体中B位元素对乙烷CL-ODH性能的影响。采用固定床... 化学链循环氧化脱氢技术(CL-ODH)是一个多功能的平台,它可以利用载氧体中晶格氧的选择性氧化这一特性,实现乙烷向乙烯的高值化转化。本研究探讨了MgX_(2)O_(4)(X=Cr、Fe或Mn)型尖晶石载氧体中B位元素对乙烷CL-ODH性能的影响。采用固定床和H_(2)-TPR、O_(2)-TPD、TG、原位拉曼、SEM、TEM等方法对MgX_(2)O_(4)尖晶石进行了性能测试和表征。结果表明,MgCr_(2)O_(4)仅释放微量表面吸附氧,更倾向于催化乙烷转化为焦炭和氢气。MgFe_(2)O_(4)通过提供更多的表面晶格氧,促进乙烷深度氧化成CO_(2)。MgMn_(2)O_(4)载氧体在乙烷CL-ODH反应中能够释放出大量的体相晶格氧,它可以选择性燃烧氢气以推进反应正向进行,增加乙烯的选择性,实现了73.72%的乙烷转化率和81.46%的乙烯选择性。此外,MgMn_(2)O_(4)催化剂在乙烷CL-ODH反应中进行了30次的氧化还原循环实验,表现出稳定的反应性能,在整个循环测试中乙烯收率大约为62.00%。MgX_(2)O_(4)尖晶石氧化物中B位元素影响了其晶格氧的供应能力,从而影响了其在乙烷CL-ODH反应中的性能。 展开更多
关键词 乙烷CL-ODH MgX_(2)O_(4)尖晶石型载氧体 乙烷生产乙烯 MgMn_(2)O_(4)
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不同温度下二氧化硫与乙烷水合物体系的模拟研究 被引量:1
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作者 张文宇 刘子西 +2 位作者 赵漫 谢秋云 冯华杰 《海南师范大学学报(自然科学版)》 CAS 2024年第1期65-69,共5页
采用分子动力学模拟计算方法,在10 MPa的压力条件下,对二氧化硫和乙烷水合物体系,分别在275、285、295、305 K等不同温度下的变化情况进行模拟研究。预测了二氧化硫、乙烷、水的扩散系数,探讨了密度、氢键数和配位数等结构性质。结果表... 采用分子动力学模拟计算方法,在10 MPa的压力条件下,对二氧化硫和乙烷水合物体系,分别在275、285、295、305 K等不同温度下的变化情况进行模拟研究。预测了二氧化硫、乙烷、水的扩散系数,探讨了密度、氢键数和配位数等结构性质。结果表明,水受到温度的影响较大,二氧化硫明显比乙烷更容易与水结合,乙烷被水和二氧化硫排挤而大量聚集,能够达到利用二氧化硫置换和收集乙烷的目的。 展开更多
关键词 二氧化硫 乙烷 分子动力学模拟 扩散系数
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十溴二苯乙烷对小鼠肝脏和肾脏的毒性研究
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作者 姜玟 冀禹彤 +7 位作者 齐凯歌 周淑馨 李振民 何家康 韦英益 胡庭俊 王蕾 于美玲 《动物医学进展》 北大核心 2024年第11期45-51,共7页
为探讨作为传统溴系阻燃剂十溴二苯醚(BDE-209)替代品的新型阻燃剂十溴二苯乙烷(DBDPE)暴露对小鼠肝肾功能的影响,将60只雄性小鼠随机分为5组,每天分别给予低、中、高剂量(5、50、500 mg/kg体重)的DBDPE,对照组给予相同体积的玉米油,联... 为探讨作为传统溴系阻燃剂十溴二苯醚(BDE-209)替代品的新型阻燃剂十溴二苯乙烷(DBDPE)暴露对小鼠肝肾功能的影响,将60只雄性小鼠随机分为5组,每天分别给予低、中、高剂量(5、50、500 mg/kg体重)的DBDPE,对照组给予相同体积的玉米油,联合染毒组每天给予50 mg/kg体重的DBDPE和BDE-209,每天灌胃1次,连续暴露60 d。试验期间观察小鼠的一般体征,测量小鼠体质量,末次染毒后测定小鼠血清生化指标、肝脏和肾脏系数,通过苏木素-伊红(HE)、油红O和刚果红染色观察小鼠肝脏和肾脏组织病理学变化。结果显示,与对照组相比,染毒组小鼠临床体征未见异常,体质量无显著变化;高剂量组小鼠肝脏系数显著升高(P<0.05),中剂量组小鼠肾脏系数极显著降低(P<0.01)。高剂量组小鼠血清中尿素(UA)含量极显著升高(P<0.01),中剂量组小鼠血清中白蛋白(ALB)含量和碱性磷酸酶(ALP)活性极显著升高(P<0.01),甘油三酯(TG)含量降低(P<0.05)。组织病理学结果可见,各攻毒组小鼠肝脏细胞均发生不同程度的脂肪变性和坏死,高剂量组小鼠肾脏间质有大量淀粉样物质沉着。结果表明,每天500 mg/kg体重DBDPE暴露导致小鼠肝肾组织结构改变,诱导小鼠肝肾组织细胞代谢紊乱和功能障碍,对肝肾具有毒性效应。 展开更多
关键词 十溴二苯乙烷 毒性 肝肾功能 小鼠
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固载Cu(Ⅰ)的π络合MOF吸附剂用于乙烷/乙烯的选择性分离
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作者 王涛虹 王超 +5 位作者 李政 刘莹 田歌 常刚刚 阳晓宇 鲍宗必 《化工学报》 EI CSCD 北大核心 2024年第7期2565-2573,共9页
金属有机框架材料作为常见的吸附剂,已被广泛地应用于乙烷和乙烯气体混合物的分离,其中引入金属离子所产生π-络合作用可以显著提高MOFs对乙烯的吸附能力。在双羟基功能化后的UiO-66中负载Cu(Ⅰ),得到了优先吸附乙烯的Cu(Ⅰ)@UiO-66-(OH... 金属有机框架材料作为常见的吸附剂,已被广泛地应用于乙烷和乙烯气体混合物的分离,其中引入金属离子所产生π-络合作用可以显著提高MOFs对乙烯的吸附能力。在双羟基功能化后的UiO-66中负载Cu(Ⅰ),得到了优先吸附乙烯的Cu(Ⅰ)@UiO-66-(OH)_(2)吸附剂。羟基功能化的框架在增强极性的同时,可以与Cu(Ⅰ)产生协同效应,有效地提高了材料对乙烯/乙烷的吸附分离性能。得到的3%(质量分数)Cu(Ⅰ)@UiO-66-(OH)_(2)在298 K及1 bar(1 bar=0.1 MPa)条件下的C_(2)_H_(4)/C_(2)H_(6)IAST选择性为2.98,约为纯UiO-66-(OH)2的3倍。单组分吸附实验证明3%Cu(Ⅰ)@UiO-66-(OH)_(2)在整个压力范围下对乙烯的吸附容量均高于乙烷,并且其对乙烯的吸附热(42.81 kJ·mol-1)低于许多已报道的乙烯-选择性吸附剂。在模拟工业条件下对50/50(体积比)C_(2)_H_(4)/C_(2)H_(6)混合物进行穿透实验,进一步表明了3%Cu(Ⅰ)@UiO-66-(OH)_(2)吸附剂可以有效分离乙烷/乙烯混合物。 展开更多
关键词 乙烷 乙烯 吸附 吸附剂 选择性 π-络合作用
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天然气乙烷回收系统脱乙烷塔和液化气塔的进料位置优化
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作者 孙娟 王梓龙 +3 位作者 史世杰 程光旭 张早校 刘桂莲 《石化技术与应用》 CAS 2024年第4期266-269,共4页
采用Aspen Plus模拟软件对天然气乙烷回收系统建立了模拟模型,并对脱乙烷塔和液化气塔进行了灵敏度分析,考察了进料位置对产品质量与再沸器热负荷的影响。结果表明:随着进料位置的下移,脱乙烷塔塔顶产品中乙烷的摩尔分率呈倒U形变化,塔... 采用Aspen Plus模拟软件对天然气乙烷回收系统建立了模拟模型,并对脱乙烷塔和液化气塔进行了灵敏度分析,考察了进料位置对产品质量与再沸器热负荷的影响。结果表明:随着进料位置的下移,脱乙烷塔塔顶产品中乙烷的摩尔分率呈倒U形变化,塔底产品中乙烷的摩尔分率和再沸器热负荷呈U形变化,脱乙烷塔最适宜的进料位置为第17块塔板上方;随着进料位置的下移,液化气塔再沸器热负荷呈U形变化,塔底异戊烷和正戊烷的摩尔分率均呈倒U形变化,而塔顶产品中丙烷的摩尔分率逐渐减小,液化气塔最适宜进料板位置为第8~10块塔板。 展开更多
关键词 天然气 乙烷回收系统 脱乙烷塔 液化气塔 进料板 优化
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气相乙烷管道泄漏扩散特征模拟分析
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作者 黄彩英 蒲红宇 +1 位作者 潘灏航 文驭天 《化学工程》 CSCD 北大核心 2024年第1期64-69,81,共7页
为研究气相乙烷管道泄漏扩散后的影响,以某公司拟建的一条乙烷输送管道为工程背景,采用CFD(计算流体动力学)软件,对不同泄漏孔径、不同风速下的气相乙烷管道泄漏进行了模拟分析,探讨其泄漏扩散特征以及危险范围的演变情况。结果表明:随... 为研究气相乙烷管道泄漏扩散后的影响,以某公司拟建的一条乙烷输送管道为工程背景,采用CFD(计算流体动力学)软件,对不同泄漏孔径、不同风速下的气相乙烷管道泄漏进行了模拟分析,探讨其泄漏扩散特征以及危险范围的演变情况。结果表明:随泄漏孔径增大,乙烷的扩散形状发生改变,小孔泄漏扩散在土壤中的形状演变特征分为前、中、后期3个阶段,而管道全尺寸泄漏在大气中的扩散分为无风时的垂直射流扩散以及有风时的横向扩散;随泄漏孔径的增大,乙烷泄漏扩散范围变大,危险区域变大;随风速增大,乙烷全尺寸泄漏扩散高度降低,且危险浓度最远扩散距离达到峰值的时间缩短。 展开更多
关键词 气相乙烷管道 泄漏扩散 泄漏孔 CFD软件
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CeO_(2)助剂对NiO/ZrO_(2)载氧体结构及性能的影响
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作者 梁皓 于耀翔 +1 位作者 孟锦宏 孙晓敏 《石油化工》 CAS CSCD 北大核心 2024年第10期1394-1399,共6页
采用共沉淀法制备了NiO-CeO_(2)/ZrO_(2)载氧体,利用XRD,H2-TPR,XPS,Raman光谱等方法对NiO-CeO_(2)/ZrO_(2)的物理化学性质进行表征。考察了NiO-CeO_(2)/ZrO_(2)作为乙烷化学链氧化脱氢制乙烯载氧体的反应性能。实验结果表明,添加CeO_(2... 采用共沉淀法制备了NiO-CeO_(2)/ZrO_(2)载氧体,利用XRD,H2-TPR,XPS,Raman光谱等方法对NiO-CeO_(2)/ZrO_(2)的物理化学性质进行表征。考察了NiO-CeO_(2)/ZrO_(2)作为乙烷化学链氧化脱氢制乙烯载氧体的反应性能。实验结果表明,添加CeO_(2)提高了NiO-CeO_(2)中晶格氧和吸附氧的含量,Ce^(4+)进入到ZrO_(2)晶格中形成了更多缺陷和晶格应力,有利于表面氧空位的产生,促进了乙烷的氧化。在反应温度为650℃、CeO_(2)添加量为3%(w)条件下乙烷转化率达100%,乙烯选择性约为40%。晶格氧数量的增加,有利于乙烷转化率的增大,但反应温度升高会导致乙烷转化副反应发生,降低乙烯收率。 展开更多
关键词 乙烷 化学链 乙烯 NiO/ZrO_(2) CeO_(2)
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