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Promoting effect of polyoxyethylene octylphenol ether on Cu/ZnO catalysts for low-temperature methanol synthesis

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Journal of Natural Gas Chemistry 2009年第3期18卷 375-378页

作者： Ling Liu Tiansheng Zhao qingxiang ma Yufang Shen Key Laboratory of Energy Resources ＆ Chemical Engineering of Ningxia Ministry-Province Co-Cultivated State Key Laboratory Base Ningxia University Yinchuan 750021 Ningxia China

Cu/ZnO catalysts were prepared by the co-precipitation method with the addition of OP-10 （polyoxyethylene octylphenol ether） and were chemically and structurally characterized by means of XRD, BET, H2-TPR, CO-TPD and N20-titration. The effect of OP-10 addition on the activity of Cu/ZnO for the slurry phase methanol synthesis at 150℃ was evaluated. The results showed that Cu/ZnO prepared with addition of 8% OP-10 （denoted as C8） exhibited the promoted activity for the methanol synthesis. The conversion of CO and the STY （space time yield） of methanol were 42.5% and 74.6% higher than those of Cu/ZnO prepared without addition of OP-10 （denoted as CO）, respectively. The precursor of C8 contained more aurichalcite and rosasite, and the concerted effect of Cu-Zn in C8 was found to be stronger than that in CO. Compared with CO, C8 showed smaller particle size, lower reduction temperature and larger BET and Cu surface areas.

关键词： surfactant Cu/ZnO low-temperature methanol synthesis

manipulating metal-support interactions of metal catalysts for Fischer-Tropsch synthesis

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Chinese Journal of Chemical Engineering 2021年第7期34卷 220-230页

作者： Qingpeng Cheng Yunhao Liu Shuaishuai Lyu Ye Tian qingxiang ma Xingang Li Collaborative Innovation Center of Chemical Science and Engineering(Tianjin) State Key Laboratory of Chemical EngineeringTianjin Key Laboratory of Applied Catalysis Science and TechnologySchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Advanced Membranes and Porous materials Center Physical Sciences and Engineering DivisionKing Abdullah University of Science and Technology(KAUST)Thuwal 23955-6900Saudi Arabia State Key Laboratory of High-efficiency Coal Utilization and Green Chemical Engineering Ningxia UniversityYinchuan 750021China School of Chemical and Biological Engineering Lanzhou Jiaotong UniversityLanzhou 730070China

For supported metal catalyst systems,the impact on catalysis originates from the interaction between metal nanoparticles and their ***-support interactions(MSI)can change electronic properties,geometric morphologies,or chemical compositions of metal nanoparticles to make active sites have specific properties and catalytic ***-Tropsch synthesis(FTS)is one of the most effective ways to convert cheap non-petroleum-based carbon sources into high value-added chemicals or ultraclean liquid *** this review,we summarize and classify the impact of MSI on the catalytic activity,selectivity and stability of FTS *** strategies to tune MSI are introduced in detail,and the recent development of high-efficiency FTS catalysts through the manipulation of SMI strategies has been *** is emphasized that the active metal sites,which are endowed with special functions by MSI,can change the strength of adsorption bond of adsorbates,consequently controlling the product distribution.

关键词： Metal-support interactions Fischer-Tropsch synthesis Modification strategies Activity Selectivity

Effect of preparation methods on the structure and catalytic performance of Fe–Zn/K catalysts for CO2 hydrogenation to light olefins

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Chinese Journal of Chemical Engineering 2018年第4期26卷 761-767页

作者： Xu Wang Jianli Zhang Jingyu Chen qingxiang ma Subing Fan Tiansheng Zhao State Key Laboratory of High-effidency Utilization of Coal and Green Chemical Engineering College of Chemistry & Chemical Engineering Ningxia University Yinchuan 750021 China

Potassium promoted iron–zinc catalysts prepared by co-precipitation method(C–Fe–Zn/K),solvothermal method(S–Fe–Zn/K)and hydrothermal method(H–Fe–Zn/K)could selectively convert CO_2to light olefins,*** physicochemical properties of the obtained catalysts were determined by SEM,N_2physisorption,XRD,H_2-TPR,CO_2-TPD and XPS *** results demonstrated that preparation methods had great influences on the morphology,phase structures,reduction and adsorption behavior,and hence the catalytic performance of the *** samples prepared by hydrothermal and co-precipitation method generated small uniform particles and led to lower specific surface *** contrast,microspheres with larger specific surface area were formed by self-assembly of nanosheets using solvothermal ***_2O_4was the only detectable phase in the fresh C–2Fe–1Zn/K,S–3Fe–1Zn/K and S–2Fe–1Zn/K ***_2O_4and ZnO co-existed with increasing Zncontent in S–1Fe–1Zn/K sample,while ZnO and Fe_2O_3could be observed over H–2Fe–1Zn/K *** the used samples contained Fe_3O_4,ZnO and Fe_5C_*** peak intensity of ZnO was strong in the AR-H–2Fe–1Zn/K sample while it was the lowest in the AR-C–2Fe–1Zn/K sample after *** formation of ZnFe_2O_4increased the interaction between iron and zinc for C–2Fe–1Zn/K and S–Fe–Zn/K samples,causing easier reduction of Fe_2O_3to Fe_3O_*** surface basicity of the sample prepared by co-precipitation method was much more than that of the other two *** CO_2hydrogenation,all the catalysts showed good activity and olefin *** CO selectivity was increased with increasing Zncontent over S–Fe–Zn/K samples.H–2Fe–1Zn/K catalyst preferred to the production of C_5^+***_2conversion of 54.76%and C_2~=–C_4~=contents of 57.38%were obtained on C–2Fe–1Zn/K sample,respectively.

关键词： CO2 hydrogenation Light olefins Preparation methods Iron–zinc catalyst

One-step conversion of syngas to light olefins over bifunctional metal-zeolite catalyst

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Chinese Journal of Chemical Engineering 2021年第8期34卷 101-110页

作者： Ce Du Linet Gapu Chizema Emmerson Hondo Mingliang Tong qingxiang ma Xinhua Gao Ruiqin Yang Peng Lu Noritatsu Tsubaki Zhejiang Provincial Key Lab for Chem.&Bio.Processing Technology of Farm Product School of Biological and Chemical EngineeringZhejiang University of Science and TechnologyHangzhou 310023China Department of Applied Chemistry School of EngineeringUniversity of ToyamaGofuku 3190Toyama 930-8555Japan State Key Laboratory Cultivation Base of Natural Gas Conversion Ningxia UniversityYinchuan 750021China

Light olefins(C_(2)–C_(4))are fundamental building blocks for the manufacture of polymers,chemical intermediates,and *** this work,we realized a composite catalyst,comprising MnxZry oxides and SAPO-34 zeolite,which can convert syngas(CO+H_(2))into light *** oxide catalysts with different Mn/Zr molar ratios were facilely prepared using the coprecipitation method prior to physical mixing with SAPO-34 *** redox properties,surface morphology,electronic state,crystal structure,and chemical elemental composition of the catalysts were examined using H_(2)-TPR,SEM,XPS,XRD,and EDS techniques,*** reactions involved activation of CO and subsequent hydrogenation over the metal oxide catalyst,producing methanol and dimethyl ether as the main reaction intermediates,which then migrated onto SAPO-34 zeolite for light olefins *** of temperature,pressure and reactant gas flow rate on CO conversion and light olefins selectivity were investigated in *** Mn_(1)Zr_(2)/SAPO-34 catalyst(Mn/Zr ratio of 1:2)attained a CO conversion of 10.8%and light olefins selectivity of 60.7%,at an optimized temperature,pressure and GHSV of 380℃,3 MPa and 3000h^(−1) *** findings open avenues to exploit other metal oxides with CO activation capabilities for a more efficient syngas conversion and product selectivity.

关键词： Catalyst C-C coupling CO activation Hydrogenation Light olefins Syngas

Tuning the crystallite size of monoclinic ZrO_(2) to reveal critical roles of surface defects on m–ZrO_(2) catalyst for direct synthesis of isobutene from syngas

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Chinese Journal of Chemical Engineering 2021年第7期34卷 211-219页

作者： Xuemei Wu Minghui Tan Bing Xu Shengying Zhao qingxiang ma Yingluo He Chunyang Zeng Guohui Yang Noritatsu Tsubaki Yisheng Tan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering Ningxia UniversityYinchuan 750021China Department of Applied Chemistry School of EngineeringUniversity of ToyamaGofuku 3190Toyama 930-8555Japan China Petroleum Chemical Industry Federation Beijing 100723China

The effects of crystallite size on the physicochemical properties and surface defects of pure monoclinic ZrO_(2) catalysts for isobutene synthesis were *** prepared a series of monoclinic ZrO_(2) catalysts with different crystallite size by changing calcination temperature and evaluated their catalytic performance for isobutene synthesis from ***_(2) with small crystalline size showed higher CO conversion and isobutene selectivity,while samples with large crystalline size preferred to form dimethyl ether(DME)instead of hydrocarbons,much less to *** defects(ODefects)analyzed by X-ray photoelectron spectroscopy(XPS)provided evidence that more ODefectsoccupied on the surface of ZrO_(2) catalysts with smaller crystalline *** paramagnetic resonance(EPR)and ultraviolet–visible diffuse reflectance(UV–vis DRS)confirmed the presence of high concentration of surface defects and Zr3+on mZrO_(2)-5.9 sample,*** situ diffuse reflectance infrared Fourier transform spectroscopy(in situ DRIFTS)analysis indicated that the adsorption strength of formed formate species on catalyst reduced as the crystalline size *** results suggested that surface defects were responsible for CO activation and further influenced the adsorption strength of surface species,and thus the products distribution *** study provides an in-depth insight for active sites regulation of ZrO_(2) catalyst in CO hydrogenation reaction.

关键词： Syngas Isobutene ZrO_(2)catalyst Crystallite size Surface defects

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超临界CO_2萃取万寿菊花中叶黄素的研究

农业工程学报 2007年第8期23卷 257-260页

作者：马清香徐响高彦祥中国农业大学食品科学与营养工程学院北京100083

采用超临界CO2萃取技术,研究了从万寿菊花中萃取叶黄素的工艺条件。对影响超临界CO2萃取叶黄素的各种因素,包括分离参数、原料含水率、粉碎粒径,超临界萃取温度、压力、流速、时间等因素进行了考察,得到较佳的萃取工艺条件为:原料含水率... 详细信息

采用超临界CO2萃取技术,研究了从万寿菊花中萃取叶黄素的工艺条件。对影响超临界CO2萃取叶黄素的各种因素,包括分离参数、原料含水率、粉碎粒径,超临界萃取温度、压力、流速、时间等因素进行了考察,得到较佳的萃取工艺条件为:原料含水率10.92%,粒径40目,萃取温度60℃,压力30MPa,CO2流速15L/h,分离釜温度40℃,压力6MPa,分离釜温度20℃,时间为6h。

关键词：万寿菊超临界CO2萃取叶黄素

Cu掺杂对Au_(11)(dppf)_(4)Cl_(2)纳米团簇结构和光学性质的影响

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无机化学学报 2024年第7期40卷 1254-1260页

作者：周鹏蔡潇马清祥刘旭宁夏大学化学化工学院银川750021 南京大学化学化工学院南京210023

通过一锅还原法成功制备了合金纳米团簇Au_(11-x)Cu_(x)(dppf)_(4)Cl_(2)(x=1、2;dppf=1,1'-双(二苯基膦)二茂铁)。晶体结构解析表明,合金团簇具有与Au_(11)(dppf)_(4)Cl_(2)类似的几何结构,如含有缺陷二十面体金属内核,不同之处在于Cu... 详细信息

通过一锅还原法成功制备了合金纳米团簇Au_(11-x)Cu_(x)(dppf)_(4)Cl_(2)(x=1、2;dppf=1,1'-双(二苯基膦)二茂铁)。晶体结构解析表明,合金团簇具有与Au_(11)(dppf)_(4)Cl_(2)类似的几何结构,如含有缺陷二十面体金属内核,不同之处在于Cu原子取代了与Cl配位的Au原子。因此,Au_(11-x)Cu_(x)(dppf)_(4)Cl_(2)可视为Cu对Au_(11)(dppf)_(4)Cl_(2)模板团簇的掺杂。Cu原子的引入并未改变模板团簇Au_(11)(dppf)_(4)Cl_(2)的框架结构,但有效调控了电子结构,进而使其光吸收发生红移。

关键词：纳米团簇金属掺杂结构光吸收

KNO_3/MCM-48催化酯交换法合成碳酸二丙酯

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催化学报 2005年第11期26卷 965-970页

作者：李永昕张艳华马清祥宁夏大学天然气转化自治区重点实验室宁夏银川750021

对KNO3/MCM-48用于丙醇和碳酸二甲酯进行酯交换合成碳酸二丙酯的催化性能进行了考察.用X射线衍射(XRD)、红外光谱(IR)和X射线荧光法研究了催化剂的结构特征和表面性质.XRD结果表明,随着K负载量的增加,载体特征峰强度逐渐减弱,但仍保留MC... 详细信息

对KNO3/MCM-48用于丙醇和碳酸二甲酯进行酯交换合成碳酸二丙酯的催化性能进行了考察.用X射线衍射(XRD)、红外光谱(IR)和X射线荧光法研究了催化剂的结构特征和表面性质.XRD结果表明,随着K负载量的增加,载体特征峰强度逐渐减弱,但仍保留MCM-48的晶体结构.随着焙烧温度的升高,KNO3逐渐分解成K2O.分别考察了活性组分负载量、焙烧温度、焙烧时间和催化剂的用量以及反应时间对反应的影响.结果表明,KNO3/MCM-48催化剂对碳酸二丙酯的合成具有很高的催化活性.在反应温度363 K,反应时间6 h,催化剂用量5%,丙醇与碳酸二甲酯摩尔比为4的条件下,碳酸二甲酯的转化率可达99.9%,产物碳酸二丙酯选择性93.4%,产率93.3%.

关键词：硝酸钾 MCM-48分子筛负载型催化剂碳酸二甲酯酯交换碳酸二丙酯

MnCl_2/活性炭催化合成正丁基氨基甲酸甲酯

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石油化工 2006年第9期35卷 863-867页

作者：李永昕康有贵马清祥江苏工业学院化工系江苏常州213164 宁夏大学天然气转化实验室宁夏银川750021

通过对不同活性组分的筛选,开发出活性炭负载氯化锰(M nC l2/AC)催化剂,用于碳酸二甲酯(DMC)和正丁胺甲氧羰基化反应合成正丁基氨基甲酸甲酯(MBC)。考察了M nC l2负载量对M nC l2/AC催化剂催化性能的影响及反应温度、反应时间、催化剂... 详细信息

通过对不同活性组分的筛选,开发出活性炭负载氯化锰(M nC l2/AC)催化剂,用于碳酸二甲酯(DMC)和正丁胺甲氧羰基化反应合成正丁基氨基甲酸甲酯(MBC)。考察了M nC l2负载量对M nC l2/AC催化剂催化性能的影响及反应温度、反应时间、催化剂用量和原料配比对反应的影响。实验结果表明,适宜的M nC l2负载量为0.2mm ol/g;适宜的反应条件为:n(DMC)∶n(正丁胺)=3,催化剂的质量分数为5%,反应温度80℃,反应时间7h。在此条件下,正丁胺能完全转化,MBC的收率达到96.5%。探讨了不同载体负载的M nC l2催化剂的催化性能,发现中性载体有利于甲氧羰基化反应。

关键词：碳酸二甲酯正丁基氨基甲酸甲酯正丁胺甲氧羰基化活性炭氯化锰负载型催化剂