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Base-free aerobic oxidation of glycerol on TiO_2-supported bimetallic Au–Pt catalysts

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Journal of Energy Chemistry 2015年第5期24卷 669-673页

作者： Yihong Shen Yuming Li haichao liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable Species College of Chemistry and Molecular Engineering Peking University

The aerobic oxidation of glycerol provides an economically viable route to glyceraldehyde, dihydroxyacetone and glyceric acid with versatile applications, for which monometallic Pt, Au and Pd and bimetallic Au-Pt, Au- Pd and Pt-Pd catalysts on TiO2 were examined under base-free conditions. Pt exhibited a superior activity relative to Pd, and Au-Pd and Pt-Pd while Au was essentially inactive. The presence of Au on the Au-Pt/TiO2 catalysts led to their higher activities （normalized per Pt atom） in a wide range of Au/Pt atomic ratios （i.e. 1/3-7/1 ）, and the one with the Au/Pt ratio of 3/1 exhibited the highest activity. Such promoting effect is ascribed to the increased electron density on Pt via the electron transfer from Au to Pt, as characterized by the temperature-programmed desorption of CO and infra-red spectroscopy for CO adsorption. Meanwhile, the presence of Au on Au-Pt/TiO2, most like due to the observed electron transfer, changed the product selectivity, and facilitated the oxidation of the secondary hydroxyl groups in glycerol, leading to the favorable formation of dihydroxyacetone over glyceraldehyde and glyceric acid that were derived from the oxidation of the primary hydroxyl groups. The synergetic effect between Au and Pt demonstrates the feasibility in the efficient oxidation of glycerol to the targeted products, for example, by rational tuning of the electronic properties of metal catalysts.

关键词： Glycerol aerobic oxidation Glyceraldehyde Dihydroxyacetone Bimetallic Au-Pt catalyst Synergetic effect

China's Industrial Sector Reports Profit Growth in First Quarter

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China Oil & Gas 2003年第2期10卷 20-21页

作者： liu haichao

China's industrial enterprises made profits of 159.1 billion yuan (US$19.2billion) during the first quarter of this year, nearly double that of the same period last year, the National Bureau of Statistics in late April. The profit growth, which stood at 94.3 per cent,was much faster than the 20.6 per cent rate recorded for the whole of 2002.

关键词：中国工业利润出口贸易固定资产经济增长

Selective biomass conversion over novel designed tandem catalyst

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Journal of Bioresources and Bioproducts 2024年第4期9卷 508-517页

作者： Fatima-Zahra Azar Achraf El Kasmi MariaÁngeles Lillo-Ródenas Maria del Carmen Román-Martínez haichao liu Department of Inorganic Chemistry and Materials Institute Faculty of SciencesUniversity of Alicante.Alicante E-03080Spain Sustainable Materials Research Center University of Mohammed Ⅵ PolytechnicBenguerir 43150Morocco Laboratory LSIA ENSAHAbdelmalek Essaadi UniversityTetouan 93030Morocco College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China

Selective conversion of biomass into targeted molecules like polyols, especially, from cellulosic compounds, is being widely investigated as a sustainable process to produce biodiesel and bio- additives. The known process involves two steps, namely hydrolysis and hydrogenation. Thus, it requires two different catalytic materials or bifunctional catalysts. In this context, the present work reports a new catalytic approach based on the use of tandem catalysts, consisting of the combination of an acid solid catalyst (active for hydrolysis) and a supported metal catalyst (active for hydrogenation). Two different functionalized activated carbons and the resin Amberlyst 15 have been tested as solid acid catalysts, and Ru nanoparticles supported on the original activated carbon (SA) are the metal catalyst part of the tandem. All the tested tandem catalysts exhibited higher activity than the supported Ru catalyst did. The highest cellulose conversion and selectivity to sorbitol (70% and 86%, respectively) have been obtained over a novel tandem catalyst, which resulted from a physical mixture between a sulfuric acid modified SA carbon (SASu) and Ru loaded SA (Ru/SA), leading to a tandem catalyst (Ru/SA + SASu). This novel-designed tandem catalyst is reusable. Based on tandem catalysts with a solid-solid system combination, the adopted novel- designed catalytic approach is cost-efficient and sustainable, and can be considered promising for the green production of high-added-value chemicals.

关键词： Biomass Tandem catalysts Carbon materials One-pot conversion Sustainability

Promoting effect of chloride ions on selective oxidation of methanol to methyl formate over zirconia-supported ruthenium oxide catalysts

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Journal of Energy Chemistry 2013年第3期22卷 512-516页

作者： Weizhen Li Hongpeng Zhang Xiaohui He haichao liu Beijing National Laboratory for Molecular Sciences State Key Laboratory for Structural Chemistry of Stable and Unstable SpeciesCollege of Chemistry and Molecular EngineeringPeking University

The effect of chloride ions on a monoclinic ZrO2-supported RuOx （RuOx/m-ZrO2） catalyst with a Ru surface density of 0.3 Ru/nm2 was studied in the selective oxidation of methanol to methyl formate （MF） at a low temperature of 373 K. The m-ZrO2 support was Cl-free, and Cl- ions were introduced into the RuOx/m-ZrO2 catalyst by impregnation with zirconium oxychloride or ammonium chloride and subsequent thermal treatment in air at 673 K. The structures of these catalysts were characterized by X-ray diffraction, Raman and X-ray photoelectron spectroscopies. Their reducibility was probed by temperature-programmed reduction in H2. The RuOx domains were present as highly dispersed Rut42- structure on m-ZrO2 with similar reducibility for the RuOx/m-ZrO2 samples irrespective of modification with or without Cl ions. Introduction of appropriate amounts of zirconium oxychloride into RuOx/m-ZrO2 led to a remarkable increase in the methanol oxidation rate and MF selectivity, whereas introduction of ammonium chloride or zirconyl nitrate significantly inhibited the catalytic performance of RuOx/m-ZrO2. The promoting effect of Cl- ions derived from zirconium oxychloride can be tentatively attributed to their roles in facilitating the adsorption of methanol and desorption of MF product or its intermediates. This finding provides novel insights into the promoting effect of Cl- ions on oxides-based catalysts for selective oxidation reactions.

关键词： methanol oxidation ruthenium oxide monoclinic zirconia chloride promoting effect methyl formate

Machine learning and bioinformatics to identify biomarkers in response to Burkholderia pseudomallei infection in mice

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BIOCELL 2024年第4期48卷 613-621页

作者： YAO FANG FEI XIA FEIFEI TIAN L EI QU FANG YANG JUAN FANG ZHENHONG HU haichao liu Department of Respiratory and Critical Care Medicine General Hospital of Center Theater of PLAWuhan430070China School of Medicine Wuhan University of Science and TechnologyWuhan430065China School of Life Science and Engineering Southwest Jiaotong UniversityChengdu611756China

Objective:In the realm of Class I pathogens,Burkholderia pseudomallei(BP)stands out for its propensity to induce severe *** the intricate interactions between BP and host cells is imperative for comprehending the dynamics of BP infection and discerning biomarkers indicative of the host cell response ***:mRNA extraction from BP-infected mouse macrophages constituted the initial step of our *** gene expression arrays,the extracted RNA underwent conversion into digital *** percentile shift method facilitated data processing,with the identiﬁcation of genes manifesting signiﬁcant differences accomplished through the application of the ***,a comprehensive analysis involving Gene Ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway was conducted on the differentially expressed genes(DEGs).Leveraging the ESTIMATE algorithm,gene signatures were utilized to compute risk scores for gene expression *** vector machine analysis and gene enrichment scores were instrumental in establishing correlations between biomarkers and macrophages,followed by an evaluation of the predictive power of the identiﬁed ***:The functional and pathway associations of the DEGs predominantly centered around G protein-coupled receptors.A noteworthy positive correlation emerged between the blue module,consisting of 416 genes,and the ***4,identiﬁed through support vector machine analysis among intersecting genes,indicated a robust interaction with macrophages,suggesting its potential as a robust ***4 exhibited commendable predictive efﬁcacy,with BP infection inducing its expression in both macrophages and mouse lung *** blotting in macrophages conﬁrmed a signiﬁcant upregulation of FZD4 expression from 0.5 to 24 h *** mouse lung tissue,FZD4 manifested higher expression in the cytoplasm of pulmonary epithelial cells in BP-infected lungs than in the

关键词： Burkholderia pseudomallei Microarray assay Machine learning Bioinformatics FZD4

Preface to Special Issue in Honor of the 80th Birthday of Professor Mingyuan He

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Chinese Journal of Catalysis 2020年第7期41卷 1029-1031页

作者： Zai-Ku Xie Bao-Lian Su haichao liu China Petroleum&Chemical Corporation Beijing 100728China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070HubeiChina College of Chemistry and Molecular Engineering Peking UniversityBeijing 100871China

This special issue of Chinese Journal of Catalysis is dedicated to Professor Mingyuan He on the occasion of his 80th birthday,in recognition of his distinguished contributions to many aspects in the field of catalytic science and *** He was born on February 8,1940 in Shanghai,*** 1961,he graduated from East China Textile Engineering Institute(now Donghua University),and earned his *** in applied *** then joined the Research Institute of Petroleum Processing,*** 1982?1984,he worked as a visiting scholar at the Northwestern University and the University of Texas at *** 2000,he became an adjunct professor at East China Normal University,and established the Shanghai Key Laboratory of Green Chemistry and Chemical Processes in 2003.

关键词：中国科学院院士科学技术进步奖中国科学院学部香山科学会议终身成就奖高水平学术炼油催化剂中国化学会

Cu-ZnO-Al_2O_3复合催化剂上甘油选择氢解合成丙二醇

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催化学报 2014年第5期35卷 631-643页

作者：王帅刘海超北京大学化学与分子工程学院北京分子科学国家实验室分子动态与稳态结构国家重点实验室北京100871

分别采用均匀共沉淀法、沉积-沉淀法和传统的共沉淀法制备了3种具有相似组成的Cu-ZnO-A1_2O_3催化剂(CZA-HP,CAZ-DP和CZA-CP)Ε同时还采用均匀共沉淀法制备了Cu-ZnO催化剂(CZ-HP)以用于比较.X射线衍射表征结果表明,以上方法制备的Cu-Zn... 详细信息

分别采用均匀共沉淀法、沉积-沉淀法和传统的共沉淀法制备了3种具有相似组成的Cu-ZnO-A1_2O_3催化剂(CZA-HP,CAZ-DP和CZA-CP)Ε同时还采用均匀共沉淀法制备了Cu-ZnO催化剂(CZ-HP)以用于比较.X射线衍射表征结果表明,以上方法制备的Cu-Zn-Al碱式碳酸盐前体中Cu^(2+),Zn^(2+)和Al^(3+)的混合均匀程度的顺序为CZA-DP90%).Cu-ZnO-A1_2O_3催化剂表面单位Cu原子的本征活性顺序为CZA-DP

关键词：甘油选择性氢解丙二醇铜氧化锌氧化铝碱式碳酸盐前体构效关系催化剂稳定性

氧化锆负载Pd-Cu双金属催化剂上山梨醇选择性氢解合成乙二醇和丙二醇（英文）

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催化学报 2015年第9期36卷 1552-1559页

作者：贾玉庆刘海超北京大学化学与分子工程学院北京分子科学国家实验室分子动态与稳态结构国家重点实验室北京100871

山梨醇和木糖醇等多元醇是可再生生物质转化合成液体燃料和化学品的重要平台分子,其中,可通过选择氢解反应一步制备乙二醇和丙二醇等重要化工原料,有望代替从乙烯和丙烯制备二元醇的传统石油化工工艺.目前文献中多元醇氢解反应主要使用R... 详细信息

山梨醇和木糖醇等多元醇是可再生生物质转化合成液体燃料和化学品的重要平台分子,其中,可通过选择氢解反应一步制备乙二醇和丙二醇等重要化工原料,有望代替从乙烯和丙烯制备二元醇的传统石油化工工艺.目前文献中多元醇氢解反应主要使用Ru基和Ni基催化剂等,但是不可避免地生成C-C键非选择性断裂的副产物甲烷等.与之相比,非贵金属Cu基催化剂往往具有较优异的选择性,但其活性较低和水热稳定性较差.因此,到目前为止研制具有高活性和选择性、以及良好水热稳定性的Cu基催化剂用于生物质基多元醇氢解反应仍然存在挑战.在本文中,我们采用贵金属修饰的方法提高Cu基催化剂在山梨醇选择氢解反应中的活性和水热稳定性.通过分步浸渍法合成了1%Pd-3%Cu/ZrO2、1%Pt-3%Cu/ZrO2和1%Ru-3%Cu/ZrO2双金属催化剂,并比较了它们在山梨醇氢解反应中的催化性能.在相同的反应条件下,上述催化剂中1%Pd-3%Cu/ZrO2（Cu/Pd=5）具有最优的活性及乙二醇、丙二醇和甘油的总选择性.以固体碱La（OH）3为助剂,1%Pd-3%Cu/ZrO2的山梨醇氢解活性高达20.3 h-1,是单金属1%Pd/ZrO2（8.7 h-1）和3%Cu/ZrO2（6.5 h-1）催化剂活性的2-3倍,也高于含有相同Pd、Cu含量的1%Pd/ZrO2和3%Cu/ZrO2机械混合体系的活性（12.2 h-1）.而且,Pd-Cu/ZrO2双金属催化剂对C2-C3低碳多元醇的选择性也明显优于Pd/ZrO2和Cu/ZrO 2以及二者的机械混合体系.这些结果说明Pd对Cu/ZrO2的促进作用不仅仅需要Pd与Cu两种金属的共同存在,还需要它们两者之间的相互作用.进一步发现,Pd-Cu/ZrO2双金属催化剂在Cu/Pd比为1.5-10.0的较宽范围内都表现出了较高的反应活性（17.8-20.3 h-1）以及乙二醇、丙二醇和甘油的总选择性（57.3%-62.8%）,说明较低含量Pd的存在就能够有效地改善Cu催化剂的催化性能.在493 K和5.0 MPa H2的反应条件下,以1%Pd-3%Cu/ZrO2为催化剂,在山梨醇接近完全转化时,获得了61.7%的乙二醇、丙二醇和甘油的总选择性.同时,Pd的加入还能有效地抑制水热反应条件下Cu粒子的团聚,使得Pd-Cu/ZrO2催化剂在山梨醇氢解反应中具有优良的水热稳定性和循环使用性能.在5次循环实验中1%Pd-3%Cu/ZrO2的活性和选择性基本保持不变;X-射线粉末衍射结果表明,反应后的催化剂上未观察到Cu的特征衍射峰,Cu粒子仍然保持良好的分散状态.而对于没有Pd修饰的单金属3%Cu/ZrO2催化剂,经5次循环使用后山梨醇氢解反应的活性则下降了42%;在循环反应中Cu粒子显著地聚集而长大到~30 ***吸附漫反射红外光谱结果揭示了Cu粒子倾向于在Pd粒子表面沉积,随着Cu/Pd原子比的增大,Cu粒子逐渐稀释并覆盖Pd的表面位点,说明Pd与Cu粒子之间存在紧密的接触.氢气程序升温还原结果表明,可能与氢溢流有关,Pd的加入促进了CuO的还原.然而,不同于Pd/ZrO2和Cu/ZrO2机械混合样品的TPR图谱,其显示PdO和CuO各自的还原峰,Pd-Cu双金属催化剂则只存在一个宽化的还原峰,这说明了Pd-Cu之间结构上的紧密接触使得两种金属之间存在强相互作用,其中可能存在从Pd向Cu的电子转移.综合这些结构和电子效应,可以推测Pd的存在促进了Cu粒子对山梨醇的脱氢能力和不饱和中间体的加氢能力,进而提高了Cu基催化剂在山梨醇氢解反应中的活性及目标产物的选择性.同时Pd-Cu之间的强相互作用和氢溢流效应抑制了Cu粒子在水热反应条件下的聚集,提高了催化剂的稳定性.这些结果和认识有助于指导人们为多元醇氢解和其它生物质基化学品的转化反应设计具有更高效率和水热稳定性的新型Cu基催化剂.

关键词：选择性氢解山梨醇乙二醇丙二醇钯-铜双金属催化剂

三氧化钨基催化剂在纤维素选择性转化合成二元醇反应中的活性相态

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Chinese Journal of Catalysis 2023年第3期46卷 56-63页

作者：刘玥章伟刘海超北京大学化学与分子工程学院院北京分子科学国家研究中心北京100871

纤维素是自然界最丰富的生物质资源,大量来源于农林废弃物.近年来,人们相继发展了以纤维素为原料合成高附加值化学品的多条路径,它们有望替代目前相应的化石资源路径.其中,以碳化钨(W_(2)C)、三氧化钨(WO_(3))和钨酸(H_(2)WO_(4))为代... 详细信息

纤维素是自然界最丰富的生物质资源,大量来源于农林废弃物.近年来,人们相继发展了以纤维素为原料合成高附加值化学品的多条路径,它们有望替代目前相应的化石资源路径.其中,以碳化钨(W_(2)C)、三氧化钨(WO_(3))和钨酸(H_(2)WO_(4))为代表的钨基催化剂表现出选择性断裂糖分子C-C键的独特催化性质,结合不同种类的共催化剂,可以将纤维素直接解聚转化为乙二醇、1,2-丙二醇、乙醇和乳酸等多种重要的C2,3产物.然而,钨基催化剂在纤维素反应中的真实状态和活性相结构尚不确定.W_(2)C最早被报道可以高效催化纤维素直接转化为乙二醇.随后,我们发现晶态WO_(3)也具有相似的催化性能,W_(2)C在反应后其表面被WO_(3)所覆盖.在纤维素反应中,氢气可以将H_(2)WO_(4)还原为钨青铜(H_(x)WO_(3))物种.本文以WO_(3)和H_(2)WO_(4)为代表性钨基催化剂,采用X射线粉末衍射(XRD)和紫外可见光谱(UV-Vis)研究反应前后的结构性质,结合反应动力学,对比不同粒径大小的WO_(3)催化剂的活性,识别它们在纤维素转化反应中的真实活性相态.纤维素反应在478 K, 6 MPa H_(2)条件下的水中进行, Ru/C为加氢催化剂.纤维素转化率和产物选择性与WO_(3)的用量密切相关,随着WO_(3)的添加并将其用量逐渐增加到1.0 g,纤维素转化率从12.5%提高到23.5%,乙二醇选择性从7.5%增至51.5%,而己糖醇选择性则从64.7%下降到16.9%.XRD结果表明, WO_(3)反应前呈现单斜相(m-WO_(3)),而反应后转变为t-H_(0.33)WO_(3),后者在空气中暴露1 h后又被氧化为m-WO_(3).进一步通过时间分辨XRD和UV-Vis光谱表征发现,在纤维素反应条件下的还原气氛中,WO_(3)经由WO_(3)→H_(0.23)WO_(3)→H_(0.33)WO_(3)的路径被还原,反应后在暴露的空气中又被氧化为起始状态的WO_(3).同样, H_(2)WO_(4)也经历了相似的变化过程.在纤维素反应中被还原为t-H_(0.33)WO_(3),而暴露到空气中时则被氧化为WO_(3),但并未转变为起始的H_(2)WO_(4).对于W, WO_(2)和W_(2)C,在反应后它们的表面几乎被WO_(3)层覆盖, 95%以上的表面物种为WO_(3).显然,无论钨基催化剂的初始状态如何不同,在纤维素转化合成乙二醇反应条件下和暴露空气后,都会经历WO_(3)→H_(x)WO_(3)→WO_(3)的氧化还原循环.本文还研究了在纤维素反应中WO_(3)和H_(x)WO_(3)的溶解性质,即它们呈现多相催化剂还是均相催化剂的特征.尽管常温下WO_(3)在水中不溶解,但是在纤维素反应的较高温度条件下,其在水中的溶解性质尚不清楚.为此,采用了两种不同粒径和比表面积的WO_(3)样品:一个晶粒尺寸为25 nm,比表面积为18 m^(2)/g,而另一个晶粒尺寸为63 nm,比表面积为1.9 m^(2)/g.它们在催化纤维素反应中,前者表现出较高的转化率和乙二醇选择性.该催化活性与粒径和比表面积密切相关的特性反映出WO_(3)/H_(x)WO_(3)是以多相催化剂形式参加反应.进一步通过测量水的电导,发现从室温到453 K, WO_(3)和H_(x)WO_(3)的存在不能改变水的电导,证明它们在纤维素反应条件下的高温水中也不发生溶解.综上所述,在纤维素反应的还原性气氛中,钨基催化剂经历WO_(3)→H_(0.23)WO_(3)→H_(0.33)WO_(3)的还原过程,而反应后H_(0.33)WO_(3)物种暴露在空气中则被氧化为WO_(3).在纤维素反应过程中, WO_(3)和H_(x)WO_(3)不发生溶解,而是以多相形态催化纤维素转化为二元醇,揭示了钨基催化剂在还原反应条件下的真实状态.

关键词：纤维素三氧化钨钨青铜乙二醇加氢