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Steam reforming of acetic acid over Ni/biochar of low metal-loading:Involvement of biochar in tailoring reaction intermediates renders superior catalytic performance

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Chinese Journal of chemical Engineering 2024年第4期68卷 241-252页

作者： Yunyu Guo Yiran Wang Shu Zhang Yi Wang Song Hu Jun Xiang Walid Nabgan Xun Hu School of Material Science and Engineering University of JinanJinan 250022China Joint International Research Laboratory of Biomass Energy and Materials College of Materials Science and EngineeringNanjing Forestry UniversityNanjing 210037China State Key Laboratory of Coal Combustion Huazhong University of Science and TechnologyWuhan 430074China departament d'Enginyeria Química Universitat Rovira i VirgiliTarragona 43007Spain

Biochar is a reactive carrier as it may be partially gasified with steam in steam reforming,which could influence the formation of reaction intermediates and modify catalytic ***,the Ni/biochar as well as two comparative catalysts,Ni/Al_(2)O_(3) and Ni/SiO_(2),with low nickel loading(2%(mass))was conducted to probe involvement of the varied carriers in the steam *** results indicated that the Ni/biochar performed excellent catalytic activity than Ni/SiO_(2) and Ni/Al_(2)O_(3),as the biochar carrier facilitated quick conversion of the -OH from dissociation of steam to gasify the oxygen-rich carbonaceous intermediates like C=O and C-O-C,resulting in low coverage while high exposure of nickel species for maintaining the superior catalytic *** converse,strong adsorption of aliphatic intermediates over Ni/Al_(2)O_(3) and Ni/SiO_(2) induced serious coking with polymeric coke as the main type(21.5%and 32.1%,respectively),which was significantly higher than that over Ni/biochar(3.9%).The coke over Ni/biochar was mainly aromatic or catalytic type with nanotube morphology and high *** high resistivity of Ni/biochar towards coking was due to the balance between formation of coke and gasification of coke and partially biochar with steam,which created developed mesopores in spent Ni/biochar while the coke blocked pores in Ni/Al_(2)O_(3) and Ni/SiO_(2) catalysts.

关键词： Steam reforming Acetic acid Ni/biochar catalyst Property of coke Reaction intermediates

ScY@C_(3v)(8)-C_(82):Metal-Metalσ^(2)Bond in Mixed Rare-Earth Di-metallofullerenes

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Chinese Journal of Chemistry 2023年第15期41卷 1809-1814页

作者： Lihao Zheng Yannick Roselló Yingjing Yan Yang-Rong Yao Xiaolin Fan Josep M.Poblet Antonio Rodríguez-Fortea Ning Chen College of Chemistry Chemical Engineering and Materials Scienceand State Key Laboratory of Radiation Medicine and ProtectionSoochow UniversitySuzhouJiangsu 215123China departament de Quimica Fisica i Inorganica Universitat Rovira i VirgiliMarcelli Domingo 143007 TarragonaSpain Department of Materials Science and Engineering CAS Key Laboratory of Materials for Energy ConversionAnhui Laboratory of Advanced Photon Science and TechnologyUniversity of Science and Technology of ChinaHefeiAnhui 230026China

Comprehensive Summary The experimental investigation of rare-earth metal-metal bonds remains a challenge in the study of chemical ***,we report the synthesis and characterization of a novel heteronuclear di-metallofullerene,ScY@C_(3v)(8)-C_(82),which contains a mixed rare-earth metal-metal ***@C_(3v)(8)-C_(82)was successfully synthesized by arc-discharging method and characterized by mass spectrometry,UV-vis-NIR spectroscopy and single-crystal X-ray diffraction crystallography,which unambiguously determined its molecular *** calculations were also performed to study the optimized positions of Sc-Y metallic dimer and the electronic *** combined experimental and theoretical results confirmed that both Sc and Y atoms transfer two electrons to the C_(3v)(8)-C_(82)cage,i.e.,(ScY)4+@(C_(3v)(8)-C_(82))4-.In particular,a covalent Sc-Yσ2 bond,which has never been reported before,is proven to be formed inside C_(3v)(8)-C_(82)fullerene *** work presents a novel di-metallofullerene containing mixed rare-earth metal-metal bond and expands the understanding of metal-metal bonding of rare earth elements.

关键词： Fullerenes Endohedral fullerenes Rare earths Densityfunctional calculations Metal-metal bond

The Influence of Poly(Vinyl Alcohol)on Oil Release Behavior of Polylactide-Based Composites Filled with Linseed Cake

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Journal of Renewable Materials 2020年第4期8卷 347-363页

作者： Olga Mysiukiewicz Mateusz Barczewski Joanna Szulc Division of Polymer Processing Institute of Material TechnologyPoznan University of TechnologyPoznan61-138Poland departament of Food Industry Technology and Engineering Faculty of Chemical Technology and EngineeringUTP University of Science and TechnologyBydgoszcz85-326Poland

In order to limit the negative impact of industry on natural environment,ecological alternatives to conventional polymers are being *** of the most popular“green”polymers is polylactide,which can also be successfully applied as a matrix of *** application of ground linseed cake as a filler for polylactide-based composites is in line with the idea of Circular Economy,and moreover it provides a modifying effect on the polymer by increasing its crystallinity and reducing its *** effect is caused by the presence of linseed oil which can be released to the polymeric matrix in a non-controlled *** order to control the miscibility of the oil and the polymer,we modified the filler particles with poly(vinyl alcohol)before introducing it to the *** concluded that poly(vinyl alcohol),which does not mix with oil,encapsulated the active ingredients inside the filler *** evaluated the mechanical properties of the composites containing 5,10,20 and 30 wt%of the filler in a static tensile stress and by means of dynamic mechanical thermal *** and thermal properties were tested using differential scanning calorimetry as well as thermogravimetric ***’microstructure was evaluated by Scanning Electron *** was found that modifying the oil-rich filler with poly(vinyl alcohol)helps to reduce its release to the matrix and thus limits the plasticizing effect of linseed *** result was in accordance with our hypothesis.

关键词： Polylactide poly(vinyl alcohol) waste filler oil release

ECF Bleaching with Molybdenum Activated Acid Peroxide and its Impact on Eucalyptus Pulp Properties and Effluent Quality

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Natural Resources 2011年第1期2卷 61-70页

作者： Marco Antonio Bandeira Azevedo Vanya Marcia Duarte Pasa Hannu Hamalainen Ann Honor Mounteer Rubens Chaves de Oliveira Jorge Luiz Colodette departament of chemical Universidade Federal de Minas GeraisBelo HorizonteBrazil Kemira Oy VaasaFinland departament of Forest Engineering Universidade Federal de VicosaVicosaBrazil

Acid hydrogen peroxide catalyzed with molybdenum (PMo stage) is effective to decrease pulp kappa number and potentially minimize chlorine dioxide demand in subsequent ECF bleaching. This study aimed at developing cost-effective methods for applying PMo as the first stage bleaching for eucalyptus kraft pulp and evaluating their impact on pulp properties and effluent quality in relation to current ECF bleaching techniques. The PMo(EP)DP and A/PMo(EP)DP sequences proved to be most cost-effective for PMo stage application. The pulp properties and effluent quality derived from bleaching with these two sequences were compared with those of the conventional bleaching with the DHT(EP)DP sequence. The PMo(EP)DP sequence produced pulp of refinability and physical properties similar to that of the reference but the A/PMo(EP)DP one resulted in pulp of 20% lower refinability and 10% lower tearing strength. Untreated effluents of the PMo(EP)DP and A/PMo(EP)DP sequences presented similar COD, but lower AOX and color than the DHT(EP)DP effluents. None of the effluents exhibited acute toxicity. The effluents from the PMo(EP)DP sequence showed much lower BOD and BOD/COD ratio than that of the A/PMo(EP)DP one. All effluents were readily treated in bench-scale reactors, and achieved COD removal efficiencies of greater than 70%.

关键词： Molybdenum Bleaching Eucalyptus Kraft Qulp Effluent Pulp Quality

Bioactive Compounds and Antifungal Activities of Extracts of Lamiaceae Species

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Journal of Agricultural Chemistry and Environment 2020年第3期9卷 85-96页

作者： Daiane Einhardt Blank Gabriela Hörnke Alves Patricia Da Silva Nascente Rogério Antonio Freitag Marlete Brum Cleff departament of chemical Universidade Federal de Vi&#231osa Vi&#231osa Brazil departament of Veterinary Universidade Federal de Pelotas Pelotas Brazil Center of chemical Pharmaceutical and Food Sciences Universidade Federal de Pelotas Pelotas Brazil

Origanum vulgare L. (oregano) and Rosmarinus officinalis L. (rosemary) are vegetal species belonging to the family Lamiaceae, popularly known as oregano and rosemary. Aromatic plants are used in the treatment and prevention of diseases and in the culinary as functional food in the preparation and conservation of foods. In the chemical composition of oregano and rosemary are present bioactive compounds with antimicrobial, antioxidant and flavoring effect. Several reports in the literature have presented the chemical composition and biological activity of the essential oils of oregano and rosemary. However, few studies have been carried out regarding the chemical composition and biological potential of the aqueous and ethanolic extracts of Origanum vulgare L. and Rosmarinus officinalis L. Evidencing a need to investigate the chemical composition and antifungal activity of these extracts. The objective of the study was to evaluate the bioactive compounds and antifungal activity of the aqueous and ethanolic extract of Origanum vulgare

关键词： Origanum vulgare Rosmarinus officinalis Antifungal Phenolics Flavonoids

Bioelectrochemically-assisted degradation of chloroform by a coculture of Dehalobacter and Dehalobacterium

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Environmental Science and Ecotechnology 2022年第4期12卷 81-86页

作者： David Fernandez-Verdejo Pilar Cortés Albert Guisasola Paqui Blánquez Ernest Marco-Urrea Biorem UAB Department of ChemicalBiological and Environmental EngineeringSchool of EngineeringUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain departament de Genetica i de Microbiologia Facultat de BioCienciesUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain GENOCOV Department of ChemicalBiological and Environmental EngineeringSchool of EngineeringUniversitat Autonoma de Barcelona08193BellaterraBarcelonaSpain

Using bioelectrochemical systems(BESs)to provide electrochemically generated hydrogen is a promising technology to provide electron donors for reductive dechlorination by organohalide-respiring *** this study,we inoculated two syntrophic dechlorinating cultures containing Dehalobacter and Dehalobacterium to sequentially transform chloroform(CF)to acetate in a BES using a graphite fiber brush as the *** this co-culture,Dehalobacter transformed CF to stoichiometric amounts of dichloromethane(DCM)via organohalide respiration,whereas the Dehalobacterium-containing culture converted DCM to acetate via *** were initially inoculated with Dehalobacter,and sequential cathodic potentials of-0.6,-0.7,and -0.8 V were poised after consuming three CF doses(500 μM)per each potential during a time-span of 83 *** the end of this period,the accumulated DCM was degraded in the following seven days after the inoculation of *** this point,four consecutive amendments of CF at increasing concentrations of 200,400,600,and 800 μM were sequentially transformed by the combined degradation activity of Dehalobacter and *** Dehalobacter 16S rRNA gene copies increased four orders of magnitude during the whole *** coulombic efficiencies associated with the degradation of CF reached values>60% at a cathodic potential of -0.8 V when the degradation rate of CF achieved the highest *** study shows the advantages of combining syntrophic bacteria to fully detoxify chlorinated compounds in BESs and further expands the use of this technology for treating water bodies impacted with pollutants.

关键词： Dehalobacter Dehalobacterium Chloroform Dichloromethane Bioelectrochemistry Bioremediation

Influence of the Degree of Maturation on the Bioactive Compounds in Blackberry (<i>Rubus</i>spp.) cv. Tupy

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Food and Nutrition Sciences 2012年第10期3卷 1453-1460页

作者： Josiane K. Rutz Glenise B. Voss Rui Carlos Zambiazi departament of chemical Engineering and Food Engineering Federal University of Santa Catarina Florianópolis Brazil Department of Agroindustrial Science and Technology Federal University of Pelotas Pelotas Brazil

Fruit consumption is primarily due to the increasing awareness of consumers on the health benefits of a healthy diet. Thus some small fruits stand out because they have bioactive compounds that may have health benefits. Among these fruits is the blackberry, which contains different levels of bioactive compounds depending on the maturation stage. Therefore, the aim of this study was to evaluate the phytochemical and physicochemical compositions of blackberries (cv. Tupy) at three maturation stages. It was observed that during maturation, there was a decrease in acidity, carotenoids and tocopherols and an increase in the total soluble solids, pH, anthocyanins, antioxidant activity and total amount of phenolic compounds. Epicatequin was the major phenolic compound found in blackberries.

关键词： Blackberry Phytochemicals Maturation Degree Antioxidant Activity Anthocyanins Phenolic Compounds

The importance of the bite angle of metal(Ⅲ) salen catalysts in the sequestration of CO_(2) with epoxides in mild conditions

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Green chemical Engineering 2022年第2期3卷 180-187页

作者： Anna Vidal-Lopez Sergio Posada-Perez Miquel Sola Valerio D'Elia Albert Poater Institut de Quimica Computacional i Catalisi and departament de Quimica Universitat de GironaC/Maria Aurelia Capmany6917003GironaCataloniaSpain Department of Chemistry Universitat Autonoma de BarcelonaCerdanyola del VallesCatalonia08193Spain Department of Materials Science and Engineering School of Molecular Science and EngineeringVidyasirimedhi Institute of Science and Technology(VISTEC)21210PayupnaiWang ChanThailand

Located in the middle of the fever to solve the problem of CO_(2)emissions in the environment,CO_(2)sequestration by reaction with epoxides is one of the key tools,as it not only fixes CO_(2),but also makes it functional by leading to cyclic ***,the results are focused specifically on the formation of cyclic organic carbonates catalyzed by metal-salen complexes,previously achieved with yttrium and scandium,that are compared with those of analogous complexes containing metals from the first transition series,such as cobalt or *** functional theory(DFT)calculations allow to determine whether this switch of metals will be feasible and provide the basis for instigating future experimental efforts in this *** calculations analyzing the structure and electronics of the catalysts allow us to give not only a clear picture of whether these catalysts will be efficient,but also allow us to assess which metal center is the most convenient and/or whether the catalytic reaction will occur under mild *** buried volume calculations with the SambVca packages shed light on the different catalytic pockets of monometallic first row transition metals *** III salen *** predictive catalysis results show that the bite O-M-O angle plays an essential role in the catalysis.

关键词： CO_(2)fixation Salen catalyst CO_(2)functionalization Cyclic carbonate DFT calculations Predictive catalysis

Numerical Simulation of the Shell-and-Tube Heat Exchanger:Influence of the Lower Flows and the Baffles on a Fluid Dynamics

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Advances in chemical Engineering and Science 2017年第4期7卷 349-361页

作者： Sebastiao Josédos Santos Filho Josedite Saraiva de Souza Antonio Gilson Barbosa de Lima departament of Mechanical Engineering UNINASSAUCampina GrandeBrazil departament of Mechanical Engineering Federal University of Campina GrandeCampina GrandeBrazil

This project proposes the numerical reproduction development of the water flow in a shell-and-tube heat exchanger 2:1 according to the CLASS C TEMA standard (for moderate operation conditions, with commercial application). With baffles in aluminum and copper tube for the cold fluid flow, the shell is in acrylic, and with thermal analysis efficiencies with regard to the presence or not of the baffles, that is to analyze the efficiency with only, the tubes and the shell and soon after the analysis with tubes and baffles. Heat exchangers are widely used equipment on an industrial and commercial scale, the application of these equipments on an industrial scale represents innovative processing solutions reflecting the processes efficiency, producing significant savings and lower cost, supporting the business success, and consequently offering opportunities, social responsibility, which are the pillars of sustainability. For the development of this work the methodology was used to calculate effectiveness, following the design parameters and contour conditions, it was analyzed the fluids behavior in the shell and the tube, through computational fluid dynamics (CFD) using the software ANSYS CFX 15.0. The results were compared with Excel generated worksheets calculated using the existing equations and correlations.

关键词： Heat Exchanger CFD Baffles ANSYS CFX