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Hydrodechlorination of trifluoro-trichloroethane to chlorotrifluoroethylene:Revealing the deactivation mechanism and regeneration strategy of Pd-Cu/AC catalyst

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Chinese Journal of Chemical Engineering 2024年第6期70卷 261-268页

作者： Song Tian Yicheng Chen Xiaoyu Wen Bingcheng Li Jian Lu Zile Li Feng Feng Qingtao Wang Qunfeng Zhang Xiaonian Li State key laboratory Breeding Base of green Chemistry synthesis technology Institute of Industrial Catalysis of Zhejiang University of TechnologyHangzhou 310014China State key laboratory of Fluorine&Nitrogen Chemicals Xi'an Modern Chemistry Research InstituteXi'an 710065China

Chlorotrifluoroethylene(CTFE)is a vital fluorinated olefinic monomer produced through the catalytic hydrodechlorination of trichlorotrifluoroethane(CFC-113),an eco-friendly ***,hydrodechlorination catalysts for olefin production often suffer from poor *** Pd/AC catalyst and Pd-Cu/AC catalyst prepared by co-impregnation method exhibited poor stability,Pd-Cu/AC catalyst with CFC-113 conversion dropping to around 37%after 50 h of hydrodechlorination ***-Emmett-Teller,transmission electron microscopy,X-ray photoelectron spectroscopy,and X-ray diffraction of fresh and deactivated Pd/AC catalysts indicate that the deactivation of Pd/AC catalysts is due to high-temperature agglomeration of *** analysis of fresh and deactivated Pd-Cu/AC catalysts using Brunauer-Emmett-Teller,transmission electron microscopy,and thermogravimetric analysis techniques revealed decreased dispersion of active sites,reduced surface area,catalyst aggregation deactivation,and a significant decrease in Cu ***,the results of NH3-TPD revealed that the acid sites of the catalyst increased significantly.X-ray diffraction spectra indicated the formation of new species,basic copper chloride(Cu_(2)(OH)_(3)Cl),during the *** the reaction progressed,these new species agglomerated,leading to a gradual loss of catalyst ***,the deactivated catalyst was successfully reactivated using a simple alkaline washing method.

关键词： CFC-113 Hydrodechlorination Chlorotrifluoroethylene Catalyst deactivation

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Sustainable electrochemical dearomatization for the synthesis of diverse 2,3-functionalized indolines

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green synthesis and catalysis 2024年第1期5卷 25-30页

作者： Jun Chen Rong Zhang Caiyan Ma Peng Zhang Yonghong Zhang Bin Wang Fei Xue Weiwei Jin Yu Xia Chenjiang Liu urumqi key laboratory of green catalysis and synthesis technology Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionState Key Laboratory of Chemistry and Utilization of Carbon Based Energy ResourcesCollege of ChemistryCollege of Future TechnologyXinjiang UniversityUrumqi 830017China

Herein,we achieved a green and efficient dearomatization for the synthesis of 2,3-functionalized polycyclic indolines in an electrochemical *** avoiding of external oxidants and metals approach allowed various nucleophilic sources(Nu¼anilines,TMSN3 and ROH)to perform the products,representing an environmentally benign ***,the continuous flow electrosynthesis and synthetic transformations also reveal the strong practicality of electrochemistry in organic synthesis.

关键词： green synthesis Organic electrochemistry Indole Dearomatization Cyclization

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Bimetallic CoNi single atoms supported on three-dimensionally ordered mesoporous chromia: highly active catalysts for n-hexane combustion

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green Energy & Environment 2024年第7期9卷 1122-1137页

作者： Xiuqing Hao Yuxi Liu Jiguang Deng Lin Jing Jia Wang Wenbo Pei Hongxing Dai Beijing key laboratory for green catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution Control Key Laboratory of Advanced Functional Materials Education Ministry of China Laboratory of Catalysis Chemistry and Nanoscience Department of Chemical Engineering Faculty of Environment and Life Beijing University of Technology

Developing the alternative supported noble metal catalysts with low cost,high catalytic efficiency,and good resistance toward carbon dioxide and water vapor is critically demanded for the oxidative removal of volatile organic compounds （VOCs）.In this work,we prepared the mesoporous chromia-supported bimetallic Co and Ni single-atom （Co1Ni1/meso-Cr2O3） and bimetallic Co and Ni nanoparticle (CoNPNiNP/mesoCr2O3) catalysts adopting the one-pot polyvinyl pyrrolidone （PVP）-and polyvinyl alcohol （PVA）-protecting approaches,*** results indicate that the Co1Ni1/meso-Cr2O3catalyst exhibited the best catalytic activity for n-hexane (C6H14) combustion (T50%and T90%were 239 and 263℃ at a space velocity of 40,000 mL g-1h-1;apparent activation energy and specific reaction rate at 260℃ were 54.7 kJ mol-1and 4.3×10-7mol g-1cats-1,respectively),which was associated with its higher (Cr5++Cr6+) amount,large n-hexane adsorption capacity,and good lattice oxygen mobility that could enhance the deep oxidation of n-hexane,in which Ni1was beneficial for the enhancements in surface lattice oxygen mobility and low-temperature reducibility,while Co1preferred to generate higher contents of the high-valence states of chromium and surface oxygen species as well as adsorption and activation of n-hexane.n-Hexane combustion takes place via the Mars van Krevelen（MvK） mechanism,and its reaction pathways are as follows:n-hexane→olefins or 3-hexyl hydroperoxide→3-hexanone,2-hexanone or 2,5-dimethyltetrahydrofuran→2-methyloxirane or 2-ethyl-oxetane→acrylic acid→COx→CO2and H2O.

关键词： Three-dimensional ordered mesoporous chromium oxide Supported bimetallic single-atom catalyst Cobalt−nickel single atoms n -Hexane combustion Catalytic reaction mechanism

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Electrooxidative trifunctionalization of alkenes with N-chlorosuccinimide and ArSSAr/ArSH to α,β-dichloride arylsulfoxides

Green Synthesis and Catalysis

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green synthesis and catalysis 2024年第2期5卷 131-135页

作者： Guohui Qin Renjie Wang Zhen Cheng Yonghong Zhang Bin Wang Yu Xia Weiwei Jin Chenjiang Liu urumqi key laboratory of green catalysis and synthesis technology Key Laboratory of Oil and Gas Fine ChemicalsMinistry of Education&Xinjiang Uygur Autonomous RegionState Key Laboratory of Chemistry and Utilization of Carbon Based Energy ResourcesCollege of ChemistryXinjiang UniversityUrumqi 830017China

An unprecedented electrochemical oxidative trifunctionalization of olefins with diaryl disulfides/aryl thiols and N-chlorosuccinimide in an aqueous system is *** C-Cl bonds,one C-S bond,and one S=O bond are produced simultaneously in one step from simple and commercially available starting materials with clean *** tandem methodology features as mild reaction conditions,transition metal and additional oxidant free,broad substrate scope,good functional group compatibility,and gram scale preparation.

关键词： Electrooxidation Alkenes functionalization Vicinal dichlorination Sulfoxidation Tandem reaction

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Pd Pt VO_(x)/CeO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

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Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： Jia Wang Yuxi Liu Jiguang Deng Lin Jing Xiuqing Hao Xing Zhang Xiaohui Yu Hongxing Dai Beijing key laboratory for green catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/CeO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： Ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance

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Visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)

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Chinese Chemical Letters 2024年第7期35卷 281-284页

作者： Tian-Yu Gao Xiao-Yan Mo Shu-Rong Zhang Yuan-Xu Jiang Shu-Ping Luo Jian-Heng Ye Da-Gang Yu key laboratory of green Chemistry&technology of Ministry of Education College of ChemistrySichuan UniversityChengdu 610064China State key laboratory Breeding Base of green Chemistry-synthesis technology Zhejiang University of TechnologyHangzhou 310014China State key laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China

Herein, we report the first visible-light photoredox-catalyzed carboxylation of aryl epoxides with CO_(2)to synthesize hydroxy acid derivatives. A variety of valuable β-, γ-, δ-, ε–hydroxy acid derivatives are obtained in moderate to high yields under mild conditions. This protocol shows noteworthy functionalgroup compatibility, high chemo-and regioselectivities under transition-metal-free conditions with an inexpensive organo-dye as photosensitizer. Mechanistic studies indicate that the benzylic carbanion is generated as an intermediate via the sequential single electron transfer(SSET) process.

关键词： Carbon dioxide Epoxides Visible-light photoredox catalysis Hydroxy acid Sequential single electron transfer

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Atomic-resolution Interfacial Microstructure and Thermo-electro-magnetic Energy Conversion Performance of Gd/Bi0.5Sb1.5Te3 Composites

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Energy & Environmental Materials 2024年第4期7卷 355-363页

作者： Chengshan Liu Wenjie Xu Ping Wei Shaoqiu Ke Wenjun Cui Longzhou Li Dong Liang Xianfeng Ye Tiantian Chen Xiaolei Nie Wanting Zhu Wenyu Zhao Qingjie Zhang State key laboratory of Advanced technology for Materials synthesis and Processing Wuhan University of Technology Foshan Xianhu laboratory of the Advanced Energy Science and technology Guangdong laboratory

Thermo-electro-magnetic materials with simultaneously large magnetocaloric(MC) and thermoelectric (TE) effects are the core part for designing TE/MC all-solid-state cooling *** MC phase with TE material is an effective ***,the elemental diffusion and chemical reaction occurring at the two-phase interfaces could significantly impair the cooling performance.

关键词： interfacial reaction magnetocaloric performance thermoelectric performance thermo-electro-magnetic materials

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Total synthesis of a putative yuzurimine-type Daphniphyllum alkaloid C_(14)–epi-deoxycalyciphylline H

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Chinese Chemical Letters 2024年第4期35卷 336-339页

作者： Jingping Hu Jing Xu Shenzhen Grubbs Institute and Department of Chemistry and Guangdong Provincial key laboratory of catalysis and Shenzhen key laboratory of Small Molecule Drug Discovery and synthesis Southern University of Science and TechnologyShenzhen 518055China

One of the largest subfamilies within the famous Daphniphyllum alkaloid family is made up of the yuzurimine-type(or macrodaphniphyllamine-type) alkaloids. Their complex aza-polycyclic caged structures, several contiguous stereogenic centers, and vicinal all-carbon quaternary centers make these alkaloids formidable challenge for synthetic chemists. Recently, synthesis of these alkaloids has received extensive attention from our community. Herein, we wish to report the total synthesis of C_(14)–epideoxycalyciphylline H, a putative member of yuzurimine-type alkaloid subfamily. key transformations employed in our approach include an intramolecular Prins reaction and a Pd-catalyzed enyne cycloisomerization. In addition, synthesis of a daphnezomine L-type alkaloid, paxdaphnidine A, was also studied.

关键词： Total synthesis Daphniphyllum alkaloids Yuzurimine-type alkaloids Prins reaction Enyne cycloisomerization

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Microstructure Regulation and Combustion Performance Optimization of PVDF/Al Composite Powder by Non-covalent Functionalized Graphenes

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Journal of Wuhan University of technology(Materials Science) 2024年第4期39卷 904-911页

作者：易卓然 DENG Haoyuan QIN Mei 孙一 LUO Guoqiang State key laboratory of Advanced technology for Materials synthesis and Processing Wuhan University of TechnologyWuhan 430070China

Graphene prepared by non-covalent modification of sulfonated poly(ether-ether-ketone)(SPG)was combined with polyvinylidene fluoride(PVDF)/Al to improve the PVDF/Al thermal conductivity while reducing the effect of the thermal resistance at the graphene-polymer *** regulation rule of SPG with different contents on the energy release of fluorine-containing system was *** the content of SPG is 4%,the peak pressure and rise rate of SPG/PVDF/Al composite powder during ignition reach the maximum of 4845.28 kPa and 8683.58 kPa/*** the content of SPG is 5%,the PVDF/Al composite powder is completely coated by SPG,and the calorific value of the material reachs the maximum of 29.094 kJ/*** the design and micro-control of the composite powder,the calorific value of the material can be effectively improved,but the improvement of the mass release rate still depends on the graphene content and surface modification state.

关键词： energetic materials PVDF/Al composites graphene modification energy release combustion

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Effect of Molecular Weight on Thermoelectric Performance of P3HT Analogues with 2-Propoxyethyl Side Chains

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Journal of Wuhan University of technology(Materials Science) 2024年第2期39卷 268-281页

作者：董得福 WANG Wei ZHAN Chun LI Chenglong ZHOU Qisheng 肖生强 State key laboratory of Advanced technology for Materials synthesis and Processing Wuhan University of TechnologyWuhan 430070China

By replacing hexyl chains in poly(3-hexylthiophene)(P3HT)with 2-propoxyethyls,four poly(3-(2-propoxyethyl)thiophene)(P3POET)homopolymers with comparable polydispersity indexes(PDI)and regioregularities were prepared herein in addition with step increment of about 7 kDa on numberaverage molecular weight(M_(n))from around 11 to 32 kDa(accordingly denoted as P11k,P18k,P25k,and P32k).When doped in film by FeCl_(3)at the optimized conditions,the maximum power factor(PF_(max))increases greatly from 4.3μW·m^(-1)·K^(-2)for P11k to 8.8μW·m^(-1)·K^(-2)for P18k,and further to 9.7μW·m^(-1)·K^(-2)for P25k,followed by a slight decrease to 9.2μW·m^(-1)·K^(-2)for *** close Seebeck coefficients(S)at PF_(max)are observed in these doped polymer films due to their consistent frontier orbital energy levels and Fermi *** main contribution to this PF_(max)evolution thus comes from the corresponding conductivities(σ).Theσvariation of the doped films can be rationally correlated with their microstructure evolution.

关键词： conjugated polymer molecular weight microstructure thermoelectric performance

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