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Preparation and characterization of H_4SiW_(12)O_(40)@MIL-100(Fe) and its catalytic performance for synthesis of 4,4'-MDA

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Chinese Journal of chemical Engineering 2018年第2期26卷 330-336页

作者： Yunhuan Kong Xiaomeng Cheng Hualiang An Xinqiang Zhao Yanji Wang hebei Provincial key Lab of green chemical technology and efficient energy saving School of Chemical Engineering and TechnologyHebei University of Technology

The catalytic performance of co mmonly used heteropolyacids （H3PW12O40, H4SiW12O40 and H3PMO12O40 synthesis of 4,4＇-methylenedianiline （4,4＇-MDA） from aniline and formaldehyde was evaluated and the result showed that H4SiW12O40 with moderate acid strength exhibited the best catalytic performance. Then HaSiW12O40@MIL-100（Fe） was prepared by encapsulating H4SiW12O40 within the pores of MIL-100（Fe） to facilitate its recovery and reuse. The prepared H4SiW12O40@MIL-100（Fe） was characterized by means of FT-IR, N2 adsorption-desorption, XRD, TG and then the catalytic performance was evaluated. The result showed that H4SiW12O40 was highly dispersed in the pores of MIL-100（Fe）, and both the Keggin structure of HaSiW12O40 and the crystal skeleton structure of MIL-100（Fe） could be effectively/preserved. Furthermore, H4SiW12O40@ MIL-100（Fe） showed excellent catalytic performance under the following reaction conditions： a molar ratio of aniline to formaldehyde = 5, a mass ratio of catalyst to formaldehyde = 1.2, a reaction temperature of 120 ℃ and a reaction time of 6 h. Under the above reaction conditions, the conversion of aniline was 41.1%, and the yield and selectivity of 4,4＇-MDA were 81,6% and 79.2%, respectively. Unfortunately, an appreciable loss in the catalytic activity of the recovered H4SiW12O40@MIL-100（Fe） was observed because of the blocking of the pores and the change of the acidity resulted from the adsorption of alkaline organics such as aniline and 4,4＇-MDA. The adsorbed alkaline organics could be cleaned up when the recovered catalyst was washed by methanol and DMF. Then the catalyst was effectively reused up to three cycles without much loss in its activity.

关键词： H4SiW12 O40@MIL- 100 ( Fe )Catalyst activation 4 4'-Methylenedianilinc synthesis Mukiphase reaction Stability

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Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu Xiaoling Liu Biao Meng Tao Chen Yu Han Jun Wang Shibo Xi Yu Zhou State key laboratory of Materials-Oriented chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst Electrocatalysis

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Effect of Zr-doping on Pd/CexZr1-xO2 catalysts for oxidative carbonylation of phenol

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Chinese Journal of chemical Engineering 2020年第10期28卷 2592-2599页

作者： Lichao Zhou Gang Feng Xiaojing Liu ZhimiaoWang Fang Li Wei Xue Yanji Wang hebei Provincial key laboratory of green chemical technology and high efficient energy saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Tianjin key laboratory of chemical Process Safety Tianjin 300130China

Ce–Zr solid solution(CexZr1-xO2,CZO)was prepared by the citric acid sol–gel *** CZO was then used as a support for Pd/CZO catalysts for the oxidative carbonylation of phenol to diphenyl *** Pd/CZO catalyst showed enhanced activity and diphenyl carbonate selectivity compared with the Pd/CeO2 *** catalytic performance of Pd/CZO was influenced by the calcination temperature of the CZO support.X-ray diffraction,scanning electron microscopy,N2 adsorption–desorption measurements,X-ray photoelectron spectroscopy and H2 temperature-programmed reduction measurements were used to investigate the effects of Zr doping and calcination *** catalytic performance of Pd/CZO and Pd/CeO2 for the oxidative carbonylation of phenol was affected by several factors,including the specific surface area,Ce^3+and/or oxygen vacancy content,oxygen species type and Pd(II)content of the *** these properties were influenced by Zr doping and the calcination temperature of the CZO support.

关键词： Diphenyl carbonate Oxidative carbonylation Ce–Zr solid solution Zr doping Support

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Ionic liquid-assisted preparation of hydroxyapatite and its catalytic performance for decarboxylation of itaconic acid

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Chinese Journal of chemical Engineering 2024年第3期67卷 9-15页

作者： Shutong Pang Hualiang An Xinqiang Zhao Yanji Wang hebei Provincial key laboratory of green chemical technology and efficient energy saving Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

The synthesis of methacrylic acid from biomass-derived itaconic acid is a green route,for it can get rid of the dependence on fossil *** order to solve the problems on this route such as use of a preciousmetal catalyst and a corrosive homogeneous alkali,we prepared a series of hydroxyapatite catalysts by an ionic liquid-assisted hydrothermal method and evaluated their catalytic *** results showed that the ionic liquid[Bmim]BF_(4) can affect the crystal growth of hydroxyapatite,provide fluoride ion for fluorination of hydroxyapatite,and adjust the surface acidity and basicity,morphology,textural properties,crystallinity,and composition of ***[Bmim]BF4 dosage and hydrothermal temperature can affect the fluoride ion concentration in the hydrothermal system,thus changing the degree of fluoridation of *** fluoride-ion concentration can lead to the formation of CaF_(2) and thus significantly decrease the catalytic performance of *** hydrothermal time mainly affects the growth of hydroxyapatite crystals on the c axis,leading to different catalytic *** suitable conditions for the preparation of this fluoridized hydroxyapatite are as follows:a mass ratio of[Bmim]BF4 to calcium salt=0.2:1,a hydrothermal time of 12 h,and a hydrothermal temperature of 130℃.A maximal methacrylic acid yield of 54.7%was obtained using the fluoridized hydroxyapatite under relatively mild reaction conditions(250℃ and 2 MPa of N_(2))in the absence of a precious-metal catalyst and a corrosive homogeneous alkali.

关键词： Ionic liquid Hydroxyapatite Itaconic acid Methacrylic Decarboxylation reaction

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Influence of Ca/P ratio on the catalytic performance of hydroxyapatite for decarboxylation of itaconic acid to methacrylic acid

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Chinese Journal of chemical Engineering 2023年第1期53卷 402-408页

Methacrylic acid,an important organic chemical,is commercially manufactured starting from fossil *** decarboxylation of itaconic acid derived for biomass is a green route to the synthesis of methacrylic *** view of the problems existing in the researches on this route such as use of noble metal catalyst,harsh reaction conditions and low desired-product yield,we prepared a series of hydroxyapatite catalysts with different Ca/P molar ratios and evaluated their catalytic *** results showed that the hydroxyapatite catalyst with a Ca/P molar ratio of 1.58 had the best catalytic *** highest yield of MAA up to 61.2%was achieved with basically complete conversion of itaconic acid under the suitable reaction conditions of 1 equivalent of NaOH,2 MPa of N_(2),250℃,and 2 *** this basis,a reaction network for the decarboxylation of itaconic acid to methacrylic acid catalyzed by hydroxyapatite was *** the aid of catalyst characterization using X-ray powder diffraction,NH3/CO2 temperature-programmed desorption,N_(2)physisorption,inductively coupled plasma optical emission spectrometry,and scanning electron microscopy,we found that the distribution of surface acid sites and basic sites,crystal growth orientation,texture properties and morphology of hydroxyapatite varied with the Ca/P molar ***,the change of the crystal growth orientation and its influence on the surface acidity and alkalinity were clarified.

关键词： Biomass-derived itaconic acid Methacrylic acid Hydroxyapatite catalyst Ca/P ratio Decarboxylation reaction

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A core–shell Ni/SiO_(2)@TiO_(2) catalyst for highly selective one-step synthesis of 2-propylheptanol from n-pentanal

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Chinese Journal of chemical Engineering 2022年第6期35卷 104-112页

作者： Hualiang An Rui Wang Wenhao Wang Daolai Sun Xinqiang Zhao Yanji Wang hebei Provincial key laboratory of green chemical technology and efficient energy saving Tianjin Key Laboratory of Chemical Process SafetySchool of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

One-step synthesis of 2-propylheptanol(2-PH)from n-pentanal via a reaction integration of n-pentanal self-condensation and successive hydrogenation is of great significance for it can simplify process flow and reduce energy *** key to promotion of 2-PH selectivity is to enhance the competitiveness of n-pentanal self-condensation with respect to its direct *** this purpose,a core–shell structured Ni/SiO_(2)@TiO_(2) catalyst was designed and *** the precise architecture of this core–shell structured catalyst,n-pentanal can be firstly in contact with TiO_(2) to 2-propyl-2-heptenal(2-PHEA)while the direct hydrogenation to n-pentanol can be effectively inhibited,and then 2-PHEA diffuses into the core of Ni/SiO_(2) and is hydrogenated to *** spatial threshold of the core–shell catalyst significantly enhanced its catalytic performance;a 2-PH selectivity of 77.9%was reached with a 100%npentanal *** 2-PH selectivity is much higher than that obtained by employing Ni/TiO_(2) ***,the reaction kinetics of one-step synthesis of 2-PH from n-pentanal catalyzed by Ni/SiO_(2)@TiO_(2) was studied and its kinetic model was established which is useful for reactor design and scale-up.

关键词： Reaction integration n-Pentanal 2-Propylheptanol Core-shell structure Reaction kinetics

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Production of Potash and N-Mg Compound Fertilizer via Mineral Shoenite from Kunteyi Salt Lake:Phase Diagrams of Quaternary System(NH_(4))_(2)SO_(4)-MgSO_(4)-K_(2)SO_(4)-H_(2)O in the Isothermal Evaporation and Crystallization Process

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Acta Geologica Sinica(English Edition) 2021年第3期95卷 1016-1023页

作者： LI Cheng CHEN Xueqing GUO Hongfei ZHOU Xue CAO Jilin hebei Provincial key Lab of green chemical technology and high efficient energy saving College of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

Based on the requirement of the new technology for producing potassium sulfate and N-Mg compound fertilizer,boussingaultite,by the reaction of the mineral shoenite from Kunteyi Salt Lake,Qinghai province,and the industrial by-product ammonium sulfate,the solubilities of the quaternary system(NH_(4))_(2)SO_(4)-MgSO_(4)-K_(2)SO_(4)-H_(2)O at 25.0℃in the isothermal evaporation and crystallization process were measured using the isothermal evaporation method,and the corresponding phase diagrams were *** to the diagram,this system contains six saturation points and six solid phase fields of crystallization,which correspond to(K1-m,(NH_(4))m)_(2)SO_(4),(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O,K_(2)SO_(4)·MgSO_(4)·6H_(2)O,MgSO_(4)·6H_(2)O,(K1-n,(NH_(4))n)_(2)SO_(4)·MgSO_(4)·6H_(2)O and MgSO_(4)·7H_(2)O,*** analyzing and calculating the isothermal evaporation and dissolution phase diagram of this quaternary system at 25.0℃,K_(2)SO_(4)and(NH_(4))_(2)SO_(4)·MgSO_(4)·6H_(2)O can be separated via K_(2)SO_(4)·MgSO_(4)·6H_(2)O and(NH_(4))_(2)SO_(4)as raw *** calculations about the proposed process were carried out and verified by experiment,which indicated that the yield of potassium sulfate was improved and the magnesium resources were fully utilized.

关键词： industrial application N-Mg compound fertilizer shoenite salt lake brine solubility phase diagram Qinghai province

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Chitosan-catalyzed n-butyraldehyde self-condensation reaction mechanism and kinetics

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Chinese Journal of chemical Engineering 2019年第10期27卷 2447-2454页

作者： Xiaoxu Han Ying Li Hualiang An Xinqiang Zhao YanjiWang hebei Provincial key Lab of green chemical technology and efficient energy saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China

The chitosan was found to possess an excellent catalytic performance in n-butyraldehyde selfcondensation to 2 E2 *** suitable conditions,the conversion of n-butyraldehyde,the yield and selectivity of 2 E2 H separately attained 96.0%,86.0%and 89.6%.The chitosan catalyst could be recovered and used for 5 times without a significant deactivation after being treated with ammonium *** order to elucidate the reaction mechanism,the adsorption and desorption of n-butyraldehyde on the surface of chitosan were studied using in situ FT-IR spectroscopy *** result showed that n-butyraldehyde interacts with\\NH2 group of chitosan to form an intermediate species with an enamine *** the reaction process of n-butyraldehyde self-condensation was monitored by React-IR technique and it was found that n-butyraldehyde self-condensation to 2-ethyl-3-hydroxyhexanal followed by a dehydration reaction to *** this basis,chitosan-catalyzed n-butyraldehyde self-condensation reaction mechanism was speculated and its reaction kinetics was *** self-condensation reaction follows auto-catalytic reaction characteristics and then the corresponding kinetic model was established.

关键词： n-Butyraldehyde Chitosan Reaction Mechanism Kinetics Autocatalysis

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Preparation of cross-linked enzyme aggregates of nitrile hydratase ES-NHT-118 from *** by macromolecular cross-linking agent

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Chinese Journal of chemical Engineering 2017年第4期25卷 487-492页

作者： Liya Zhou Haixia Mou Jing Gao Li Ma Ying He Yanjun Jiang School of chemical Engineering and technology Hebei University of TechnologyTianjin 300130China hebei Provincial key Lab of green chemical technology and high efficient energy saving Hebei University of TechnologyTianjin 300130China

Cross-linked enzyme aggregates(CLEAs) of nitrile hydratase(NHase) ES-NHT-118 from Escherichia coli were prepared by using ammonium sulfate as precipitating agent followed by cross-linking with dextran polyaldehyde for the first time. In this process, egg white was added as protein feeder for facilitating the formation of CLEAs. The optimal conditions of the immobilization process were determined. Michaelis constants(Km) of free NHase and NHase CLEAs were also determined. The NHase CLEAs exhibited increased stability at varied pH and temperature conditions compared to its free counterpart. When exposed to high concentrations of acrylamide, NHase CLEAs also exhibited effective catalytic activity.

关键词： nitrile linking acrylamide linker ammonium facilitating counterpart Michaelis dextran constants

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Enhanced stability of nitrogen-doped carbon-supported palladium catalyst for oxidative carbonylation of phenol

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Chinese Journal of chemical Engineering 2024年第1期65卷 19-28页

作者： Xiaojing Liu Ruohan Zhao Hao Zhao Zhimiao Wang Fang Li Wei Xue Yanji Wang hebei Provincial key laboratory of green chemical technology and high efficient energy saving School of Chemical Engineering and TechnologyHebei University of TechnologyTianjin 300130China Tianjin key laboratory of chemical Process Safety Tianjin 300130China hebei Industrial technology Research Institute of green chemical Industry Huanghua 061100China

Enhancing the stability of supported noble metal catalysts emerges is a major challenge in both science and ***,a heterogeneous Pd catalyst(Pd/NCF)was prepared by supporting Pd ultrafine metal nanoparticles(NPs)on nitrogen-doped carbon;synthesized by using F127 as a stabilizer,as well as chitosan as a carbon and nitrogen *** Pd/NCF catalyst was efficient and recyclable for oxidative carbonylation of phenol to diphenyl carbonate,exhibiting higher stability than Pd/NC prepared without F127 *** hydrogen bond between chitosan(CTS)and F127 was enhanced by F127,which anchored the N in the free amino group,increasing the N content of the carbon material and ensuring that the support could provide sufficient N sites for the deposition of Pd *** process helped to improve metal *** increased metal-support interaction,which limits the leaching and coarsening of Pd NPs,improves the stability of the Pd/NCF ***,density functional theory calculations indicated that pyridine N stabilized the Pd^(2+)species,significantly inhibiting the loss of Pd^(2+)in Pd/NCF during the reaction *** work provides a promising avenue towards enhancing the stability of nitrogen-doped carbon-supported metal catalysts.

关键词： Supported Pd catalyst N-doped carbon Amphiphilic triblock copolymer Pyridinic nitrogen Stability

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