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Efficient epoxidation of propylene over non-noble nickel-based catalyst promoted by alkali metals

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Science China Chemistry 2024年第11期67卷 3697-3705页

作者： Wenqian Li Wanting Li Xinxin Cao Longfei chen Yibo Qin Yanfeng Zhu Yanfei Zhang Gai Miao Lingzhao Kong Jiong Li xinqing chen State Key Laboratory of Low Carbon Catalysis and Carbon Dioxide Utilization CAS Key Laboratory of Low-carbon Conversion Science and EngineeringShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China Shanghai Synchrotron Radiation Facility Zhangjiang National LabShanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China

The application of non-noble metal catalysts in the catalytic direct gas-phase epoxidation of propylene with H2and O2to produce propylene oxide is valuable and challenging. The introduction of alkali metal promoters is one of the effective methods to improve the catalytic activity of catalysts. Herein, a series of alkali metal(Li, Na, K, Rb, and Cs)-promoted Ni/TS-1 catalysts were prepared to deeply understand the effect of alkali metals on the structure-activity relationship for gas-phase epoxidation of propylene. Among them, the Na-Ni/TS-1 catalyst exhibits the highest catalytic activity(propylene conversion of 7.35% and PO formation rate of 157.9 g h^(-1)kg_(cat)^(-1)) and the best stability(long-term stability exceeding 140 h at 200 ℃). X-ray absorption and photoelectron spectroscopy revealed that the electronic structure of Ni can be tuned by the addition of alkali metal ***3-TPD-MS, CO_(2)-TPD-MS, and C_(3)H_(6)-TPD-MS results indicate that the acidity of the catalyst can also be adjusted by the introduction of alkali metal, whereas the Na-Ni/TS-1 catalyst exhibits the strongest C_(3)H_(6) adsorption capacity. Thus, the suitable acid-base properties, unique electronic properties of Ni species, and the strongest propylene adsorption capacity resulted in improved propylene gas-phase epoxidation activity of Na-Ni/TS-1 catalyst. This study not only provides a new strategy for the practical application of nickel-based catalysts in the gas-phase epoxidation of propylene but also provides insights into the promoting effect of alkali metals.

关键词： propylene epoxidation Ni/TS-1 catalyst alkali metal precipitating agents

Preparation of polymer-supported hydrated ferric oxide based on Donnan membrane effect and its application for arsenic removal

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Science China Chemistry 2008年第4期51卷 379-385页

作者： ZHANG QingJian PAN BingCai chen xinqing ZHANG WeiMing PAN BingJun ZHANG QuanXing L.LV X.S.ZHAO State Key Laboratory of Pollution Control and Resource Reuse School of the EnvironmentNanjing UniversityNanjing 210093China Department of Chemical and Biomolecular Engineering National University of Singapore10 Kent RidgeSingapore 119260Singapore 不详

In the present study a novel technique was proposed to prepare a polymer-supported hydrated ferric oxide (D201-HFO) based on Donnan membrane effect by using a strongly basic anion exchanger D201 as the host material and FeCl3-HCl-NaCl solution as the reaction environment. D201-HFO was found to exhibit higher capacity for arsenic removal than a commercial sorbent Purolite ArsenX. Furthermore, it presents favorable adsorption selectivity for arsenic removal from aqueous solution, as well as satis- factory kinetics. Fixed-bed column experiments showed that arsenic sorption on D201-HFO could re- sult in concentration of this toxic metalloid element below 10 μg/L, which was the new maximum con- centration limit set recently by the European Commission and imposed by the US EPA and China. Also, the spent D201-HFO is amenable to efficient regeneration by NaOH-NaCl solution.

关键词： hydrated ferrous oxide anion exchanger Donnan membrane effect arsenic sorption

Dimensional engineering of covalent organic frameworks derived carbons for electrocatalytic carbon dioxide reduction

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SusMat 2023年第6期3卷 834-842页

作者： Guojuan Liu Xuewen Li Minghao Liu Xiubei Yang Zhuangyan Guo xinqing chen Qing Xu Gaofeng Zeng Yue He CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research Institute(SARI)Chinese Academy of Sciences(CAS)ShanghaiChina School of Chemical Engineering University of Chinese Academy of SciencesBeijingChina Shanghai Ninth People’s Hospital Shanghai Jiao Tong UniversityShanghaiChina

Covalent organic frameworks(COFs)have been developed as the precursors to construct porous carbons for electrocatalytic ***,the influences of carbon dimensions on the catalytic performance are still *** this work,we have first constructed COF-derived carbons by template-synthesis strategy in different dimensions to catalyze the carbon dioxide reduction(CO_(2)RR).By using different templates,the one-dimensional(1D),two-dimensional(2D),and three-dimensional(3D)COF-derived carbons have been employed to anchor Co-porphyrin to form the Co-N5 sites to catalyze CO_(2)*** 1D catalyst templated by carbon nano tubes presents high binding ability of CO_(2),more defective sites,and higher electronic conductivity,resulting in a higher catalytic activity for CO_(2)and selectivity of CO than 2D and 3D carbon-based *** 1D catalyst delivers the turnover frequency values of 1150 h^(−1)and the FECO of 94.5%at 0.7 V versus RHE,which is significantly better than those of 2D and 3D carbon-based catalysts.

关键词： CO_(2)reduction Co-N_(5)sites covalent organic frameworks dimensional engineering templatesynthesis strategy

Operando reconstruction towards stable CuI nanodots with favorable facets for selective CO_(2) electroreduction to C2H4

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Science China Chemistry 2023年第6期66卷 1834-1843页

作者： Wenjie Xue Hongxia Liu xinqing chen Xiaoju Yang Ruoou Yang Youwen Liu Minghao Li Xuan Yang Bao Yu Xia Bo You Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Chemistry and Chemical Engineering Wuhan Textile UniversityWuhan 430200China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China State Key Laboratory of Materials Processing and Die&Mold Technology and School of Materials Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Cu-based electrocatalysts with favorable facets and Cu^(+)can boost CO_(2) reduction to valuable multicarbon ***,the inevitable Cu^(+)reduction and the phase evolution usually result in poor ***,we fabricate CuI nanodots with favorable(220)facets and a stable Cu^(+)state,accomplished by operando reconstruction of Cu(OH)_(2) under CO_(2)-and I--containing electrolytes for enhanced CO_(2)-to-C_(2)H_(4) *** X-ray absorption spectroscopy(XAS),in-situ Raman spectroscopy and thermodynamic potential analysis reveal the preferred formation of *** gas electroresponse and density functional theory(DFT)calculations reveal that CO_(2)-related species induce the exposure of the(220)plane of Cu ***,the small size of nanodots enables the adequate contact with I^(-),which guarantees the rapid formation of Cu I instead of the electroreduction to Cu^(0).As a result,the resulting catalysts exhibit a high C2H4 Faradaic efficiency of 72.4%at a large current density of 800 m A cm^(-2) and robust stability for 12 h in a flow *** in-situ ATR-SEIRS spectroscopic characterizations and DFT calculations indicate that the(220)facets and stable Cu^(+) in CuI nanodots synergistically facilitate CO_(2)/*CO adsorption and*CO dimerization.

关键词： CO_(2)reduction reaction cuprous iodide favorable facets halogen electrolyte reconstruction

Assessment of Sericin Biosorbent for Selective Dye Removal

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Chinese Journal of Chemical Engineering 2012年第3期20卷 426-432页

作者： chen xinqing LAM Koon Fung MAK Shuk Fong CHING Wai Kwong NG Tsz Nok YEUNG King Lun Department of Chemical and Biomolecular Engineering Division of Environment the Hong Kong University of Science and TechnologyHong KongChina

The silk sericin is the main residue in silk production and it is found to be a low cost and efficient bio-sorbent. In this study, sericin was characterized with various techniques including SEM （scanning electron micro- scope）, XRD, N2 physisorption, FTIR （Fourier transformed infrared spectroscopy） and XPS （X-ray photoelectron spectroscopy）. The nitrogen content of sericin was ca. 8.5 mmol.g-1 according to elemental analysis. Dye adsorption by sericin biosorbent was investigated with the acid yellow （AY）, methylene blue （MB） and copper （II） phthalocyanine-3,4＇4＂4＇＂-tetrasulfonic acid （CuPc） dyes from water. Sericin displayed large capacity for AY andCuPc adsorption with adsorption capacities of respectively 3.1 and 0.35 mmol.g-1, but it did not adsorbed methyl- ene blue dye. This selectivity is due to the basicity of amide groups in seriein biosorbents.

关键词： dye adsorption silk protein biosorbent

Enhanced MTO performance over acid treated hierarchical SAPO-34

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Chinese Journal of Catalysis 2017年第1期38卷 123-130页

作者： Shu Ren Guojuan Liu Xian Wu xinqing chen Minghong Wu Gaofeng Zeng Ziyu Liu Yuhan Sun College of Science Shanghai University Shanghai 201900 China CAS Key Laboratory of Low‐Carbon Conversion Science and Engineering Shanghai Advanced Research Institute Chinese Academy of Sciences Shanghai 201210 China School of Environmental and Chemical Engineering Shanghai University Shanghai 201900 China

Hierarchical SAPO‐34 crystals were synthesized by a facile acid etching post‐treatment. Butterfly‐shaped porous patterns on four side faces and hierarchical pores composed of micropores,mesopores and macropores were formed after a nitric acid or oxalic acid treatment. The catalyticperformance of the hierarchical SAPO‐34 for the methanol to olefins (MTO) process showed that thesynergistic effect of the hierarchical pores and acid sites resulted in a longer catalyst lifetime (from210 to 390 min for the acid treated SAPO‐34) and higher selectivity to light olefins of 92%–94%.The ethylene selectivity can be adjusted between 37.4% and 51.5% by the pore size. No hierarchical SAPO‐34 was obtained after a treatment with butanedioic acid, and with this sample, fast deactivation was detected after 100 min.

关键词： Acid treatment Hierarchical pore SAPO‐34 Methanol to olefins Single‐run lifetime

Melting-assisted solvent-free synthesis of SAPO-11 for improving the hydroisomerization performance of n-dodecane

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Chinese Journal of Catalysis 2020年第4期41卷 622-630页

作者： Gan Yu xinqing chen Wenjie Xue Lixia Ge Ting Wang Minghuang Qiu Wei Wei Peng Gao Yuhan sun School of Physical Science and Technology ShanghaiTech UniversityShanghai 201210China CAS Key Laboratory of Low-Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China University of Chinese Academy of Sciences Beijing 100049China

A novel melting-assisted solvent-free route using solid oxalic acid was proposed for the post-treatment of SAPO-11 zeolite,followed by loading with 0.5 wt%Pt by the incipient wetness impregnation ***,the performance of the obtained bifunctional catalysts toward the hydroisomerization of n-dodecane was *** prepared samples were characterized by XRD,SEM,BET,XRF,Py-IR,and solid-state *** the results,it was found that the high crystallinity and uniform morphology were retained after the post-treatment and that more(002)crystal faces were exposed,which was beneficial since more acid sites were *** importantly,the total Bronsted acid sites and the ratio(Ra)of the micropore area to the total surface area were optimized by this ***,the catalytic performance was enhanced significantly,and the prepared Pt-SAPO-11-10%catalyst had the highest i-dodecane yield of 80.1%compared to 55.3%of ***,this facile and cost-effective method is promising for the hydroisomerization of normal paraffin in the production of lubricant base oils.

关键词： Hydroisomerization Zeolite SAPO-11 Melting-assist Bifunctional catalyst

Effect of alkali metals on the performance of CoCu/TiO_2 catalysts for CO_2 hydrogenation to long-chain hydrocarbons

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Chinese Journal of Catalysis 2018年第8期39卷 1294-1302页

作者： Zhibiao Shi Haiyan Yang Peng Gao xinqing chen Hongjiang Liu Liangshu Zhong Hui Wang Wei Wei Yuhan Sun[1 3a] Department of chemistry College of SciencesShanghai UniversityShanghai 200444China CAS Key Laboratory of Low‐Carbon Conversion Science and Engineering Shanghai Advanced Research InstituteChinese Academy of SciencesShanghai 201210China School of physical Science and Technology ShanghaiTech UniversityShanghai 201210China

CoCu/TiO_2 catalysts promoted using alkali metals（Li, Na, K, Rb, and Cs） were prepared by the homogeneous deposition-precipitation method followed by the incipient wetness impregnation method. The influences of the alkali metals on the physicochemical properties of the CoCu/TiO_2 catalysts and the catalytic performance for CO_2 hydrogenation to long-chain hydrocarbons（C_（5＋））were investigated in this work. According to the characterization of the catalysts based on X-ray photoelectron spectroscopy, X-ray diffraction, CO_2 temperature-programmed desorption（TPD）, and H_2-TPD, the introduction of alkali metals could increase the CO_2 adsorption and decrease the H_2 chemisorption, which could suppress the formation of CH_4, enhance the production of C_（5＋）, and decrease the hydrogenation activity. Among all the promoters, the Na-modified CoCu/TiO_2 catalyst provided the maximum C_（5＋） yield of 5.4%, with a CO_2 conversion of 18.4% and C_（5＋） selectivity of42.1%, because it showed the strongest basicity and a slight decrease in the amount of H_2 desorption;it also exhibited excellent catalytic stability of more than 200 h.

关键词： Carbon dioxide hydrogenation Long-chain hydrocarbons Carbon dioxide Fischer-Tropsch synthesis Alkali metal promoters Cobalt-coper based catalysts

信息化环境下初中生物课堂信息化教学策略探讨

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成才之路 2024年第29期 125-128页

作者：陈新青福建省南安市柳城中学福建南安362300

初中生物课堂采取信息化教学方式有助于促进理论与实践的结合,并激发学生的学习兴趣,丰富学生的学习体验,提高学生的自主学习能力。在教学实践中,教师可运用信息技术创设情境,以微课、思维可视化工具、虚拟实验室助力教学,并构建信息化... 详细信息

初中生物课堂采取信息化教学方式有助于促进理论与实践的结合,并激发学生的学习兴趣,丰富学生的学习体验,提高学生的自主学习能力。在教学实践中,教师可运用信息技术创设情境,以微课、思维可视化工具、虚拟实验室助力教学,并构建信息化评价体系,在激发学生的生物知识学习兴趣的同时,使其深度理解生物学知识,提高动手操作能力及学习效率,以此为相关领域的研究和实践提供参考、借鉴。

关键词：信息化初中生物情境微课虚拟实验室评价

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