Sample records for solid resin catalyst

  1. Resin Catalyst Hybrids

    S. Asaoka


    @@ 1Introduction: What are resin catalyst hybrids? There are typically two types of resin catalyst. One is acidic resin which representative is polystyrene sulfonic acid. The other is basic resin which is availed as metal complex support. The objective items of this study on resin catalyst are consisting of pellet hybrid, equilibrium hybrid and function hybrid of acid and base,as shown in Fig. 1[1-5].

  2. Biodiesel production from acid oils and ethanol using a solid basic resin as catalyst

    Marchetti, J.M.; Errazu, A.F. [Planta Piloto de Ingenieria Quimica, UNS-CONICET, Camino La Carrindanga km 7 (8000) Bahia Blanca (Argentina)


    In the search of an alternative fuel to substitute diesel fuel, biodiesel appears as one of the most promising sources of energy for diesel engines because of its environmental advantages and also due to the evolution of the petroleum market. Refined oil is the conventional raw material for the production of this biofuel; however, its major disadvantage is the high cost of its production. Therefore, frying oils, waste oils, crude oils and/or acid oils are being tested as alternative raw materials; nevertheless, there will be some problems if a homogeneous basic catalyst (NaOH) is employed due to the high amount of free fatty acid present in the raw oil. In this work, the transesterification reaction of acid oil using solid resin, Dowex monosphere 550 A, was studied as an alternative process. Ethanol was employed to have a natural and sustainable final product. The reaction temperature's effects, the initial amount of free fatty acid, the molar ratio of alcohol/oil and the type of catalyst (homogeneous or heterogeneous) over the main reaction are analyzed and their effects compared. The results obtained show that the solid resin is an alternative catalyst to be used to produce fatty acid ethyl esters (FAEEs) by a transesterification reaction with a final conversion over 90%. On the other hand, the time required to achieve this conversion is bigger than the one required using conventional technology which employs a homogeneous basic catalyst. This reaction time needs to be optimized. (author)

  3. Resin catalysts and method of preparation

    Smith, L.A. Jr.


    Heat stabilized catalyst compositions are prepared from nuclear sulfonic acid, for example, macroporous crosslinked polyvinyl aromatic compounds containing sulfonic acid groups are neutralized with a metal of Al, Fe, Zn, Cu, Ni, ions or mixtures and alkali, alkaline earth metals or ammonium ions by contacting the resin containing the sulfonic acid with aqueous solutions of the metals salts and alkali, alkaline earth metal or ammonium salts. The catalysts have at least 50% of the sulfonic acid groups neutralized with metal ions and the balance of the sulfonic acid groups neutralized with alkali, alkaline earth ions or ammonium ions.


    Yongdan Li; Dongfang Wu; Y.S. Lin


    The mechanical strength of solid catalysts is one of the key parameters for reliable and efficient performance of a fixed bed reactor. Some recent developments and their basic mechanics within this context are reviewed. The main concepts discussed are brittle fracture which leads to the mechanical failure of the catalyst pellets, measurement and statistical properties of the catalyst strength data, and mechanical reliability of the catalyst pellets and their packed bed. The scientific basis for the issues on the catalyst mechanical properties calls yet for further elucidation and advancement.

  5. Synthesis of biodiesel from pongamia oil using heterogeneous ion-exchange resin catalyst.

    Jaya, N; Selvan, B Karpanai; Vennison, S John


    Biodiesel is a clean-burning renewable substitute fuel for petroleum. Biodiesel could be effectively produced by transesterification reaction of triglycerides of vegetable oils with short-chain alcohols in the presence of homogeneous or heterogeneous catalysts. Conventionally, biodiesel manufacturing processes employ strong acids or bases as catalysts. But, separation of the catalyst and the by-product glycerol from the product ester is too expensive to justify the product use as an automobile fuel. Hence heterogeneous catalysts are preferred. In this study, transesterification of pongamia oil with ethanol was performed using a solid ion-exchange resin catalyst. It is a macro porous strongly basic anion exchange resin. The process parameters affecting the ethyl ester yield were investigated. The reaction conditions were optimized for the maximum yield of fatty acid ethyl ester (FAEE) of pongamia oil. The properties of FAEE were compared with accepted standards of biodiesel. Engine performance was also studied with pongamia oil diesel blend and engine emission characteristics were observed.

  6. Solid-State Microwave Synthesis of Melamine-Formaldehyde Resin

    Subhash Bajia; Rashmi Sharma; Birbal Bajia


    An efficient synthesis of melamine-formaldehyde resin has been achieved using conventional as well as microwave irradiations (without and with solid support) in different molar ratio. Resin samples were tested for their chemical as well as physical properties. The structure of all the resin has been supported by their spectral data

  7. Solid-State Microwave Synthesis of Melamine-Formaldehyde Resin

    Subhash Bajia


    Full Text Available An efficient synthesis of melamine-formaldehyde resin has been achieved using conventional as well as microwave irradiations (without and with solid support in different molar ratio. Resin samples were tested for their chemical as well as physical properties. The structure of all the resin has been supported by their spectral data

  8. Esterification of palm fatty acid distillate with epychlorohydrin using cation exchange resin catalyst

    Budhijanto, Budhijanto; Subagyo, Albertus F. P. H.


    Palm Fatty Acid Distillate (PFAD) is one of the wastes from the conversion of crude palm oil (CPO) into cooking oil. The PFAD is currently only utilized as the raw material for low grade soap and biofuel. To improve the economic value of PFAD, it was converted into monoglyceride by esterification process. Furthermore, the monoglyceride could be polymerized to form alkyd resin, which is a commodity of increasing importance. This study aimed to propose a kinetics model for esterification of PFAD with epichlorohydrin using cation exchange resin catalyst. The reaction was the first step from a series of reactions to produce the monoglyceride. In this study, the reaction between PFAD and epichlorohydirne was run in a stirred batch reactor. The stirrer was operated at a constant speed of 400 RPM. The reaction was carried out for 180 minutes on varied temperatures of 60°C, 70°C, 80°C, dan 90°C. Cation exchange resin was applied as solid catalysts. Analysis was conducted periodically by measuring the acid number of the samples, which was further used to calculate PFAD conversion. The data were used to determine the rate constants and the equilibrium constants of the kinetics model. The kinetics constants implied that the reaction was reversible and controlled by the intrinsic surface reaction. Despite the complication of the heterogeneous nature of the reaction, the kinetics data well fitted the elementary rate law. The effect of temperature on the equilibrium constants indicated that the reaction is exothermic.

  9. Catalysts for portable, solid state hydrogen genration systems

    Gabl, Jason Robert

    Hydrogen and air powered proton exchange membrane fuel cells are a potential alternative to batteries. In portable power systems, the design requirements often focus on cost efficiency, energy density, storability, as well as safety. Ammonia borane (AB), a chemical hydride containing 19.6 wt. % hydrogen, has a high hydrogen capacity and is a stable and non-toxic candidate for storing hydrogen in portable systems. Throughout this work, Department of Energy guidelines for low power portable hydrogen power systems were used as a baseline and comparison with commercially available systems. In order to make this comparison, the system parameters of a system using AB hydrolysis were estimated by developing capacity and cost correlations from the commercial systems and applying them to this work. Supporting experiments were designed to evaluate a system that would use a premixed solid storage bed of AB and a catalyst. This configuration would only require a user input of water in order to initiate the hydrogen production. Using ammonia borane hydrolysis, the hydrogen yield is ˜9 wt. %, when all reactants are considered. In addition to the simplicity of initiating the reaction, hydrolysis of AB has the advantage of suppressing the production of some toxic borazines that are present when AB is thermally decomposed. However, ammonia gas will be formed and this problem must be addressed, as ammonia is damaging to PEM fuel cells. The catalyst focused on throughout this work was Amberlyst - 15; an ion exchange resin with an acid capacity of 4.7 eq/kg and ammonia adsorbent. At less than 0.30/g, this is a cost effective alternative to precious metal catalysts. The testing with this catalyst was compared to a traditional catalyst in literature, 20% platinum in carbon, costing more than 40/g. The Amberlyst catalyst was found to reduce the formation of ammonia in the gas products from ˜3.71 wt. % with the Pt/C catalyst to 90 % to cost effective, energy dense, and safe option for

  10. Transesterification of propylene glycol methyl ether in chromatographic reactors using anion exchange resin as a catalyst.

    Oh, Jungmin; Sreedhar, Balamurali; Donaldson, Megan E; Frank, Timothy C; Schultz, Alfred K; Bommarius, Andreas S; Kawajiri, Yoshiaki


    Reactive chromatography using an anion exchange resin is proposed for a transesterification reaction of propylene glycol methyl ether (DOWANOL™ PM) with ethyl acetate to produce propylene glycol methyl ether acetate (DOWANOL™ PMA). This reaction is studied in batch and chromatographic reactors catalyzed by an anion exchange resin. Several anion exchange resins are tested and compared based on the performance of resin as an adsorbent and a catalyst. A chromatographic column is packed with a selected catalyst, AMBERLITE™ IRA904, and both reaction and chromatographic elution are studied at different temperatures and feed concentrations. The resulting chromatograms are fitted to a mathematical model to obtain adsorption equilibrium and reaction kinetic parameters by the inverse method. Compared to esterification investigated in a previous study, transesterification has advantages such as a higher conversion at lower temperature and easy removal of the byproduct which may lead to higher productivity. Deactivation of anion exchange resins is observed and potential solutions are suggested.

  11. Solid support resins and affinity purification mass spectrometry.

    Havis, Spencer; Moree, Wilna J; Mali, Sujina; Bark, Steven J


    Co-affinity purification-mass spectrometry (CoAP-MS) is a primary technology for elucidating the protein-protein interactions that form the basis of all biological processes. A critical component of CoAP-MS is the affinity purification (AP) of the bait protein, usually by immobilization of an antibody to a solid-phase resin. This Minireview discusses common resins, reagents, tagging methods, and their consideration for successful AP of tagged proteins. We discuss our experiences with different solid supports, their impact in AP experiments, and propose areas where chemistry can advance this important technology.

  12. Sulfo cation-exchange resins as heterogeneous catalysts for the reaction of styrene with formaldehyde

    Kasymova, K.A.; Sharf, V.Z.; Litvin, E.F.; Grigor' eva, E.N.


    Macroporous and gel sulfo cation-exchange resins are active catalysts for the condensation of styrene with formaldehyde. The product, 4-phenyl-1,3-dioxane was obtained in up to 97% yield. The activity of macroporous sulfo cation-exchange resins increases with decreasing particle diameter but in the case of the gel samples, granule size has only a slight effect on the reaction rate. The enhanced activity of sulfo cation-exchange resins is presumably a result of the high value of the acidity function H/sub 0/ of the sulfonic acid groups of the cation-exchange resin.

  13. Fries Rearrangement of Phenyl Acetate over Solid Acid Catalyst


    A silica-supported zirconium based solid acid (ZS) has been used as catalyst for the Fries rearrangement of phenyl acetate (PA). The catalyst showed a higher PA conversion activity and a much higher selectivity for o-hydroxyacetophenone (o-HAP) than for strongly acidic zeolite catalysts. The supported catalyst was characterized by XRD, IR, XPS, pyridine-TPD and the surface area measurements. The catalytic properties were influenced significantly by pretreatment temperature.

  14. Fries Rearrangement of Phenyl Acetate over Solid Acid Catalyst

    CanXiongGUO; YanLIU; 等


    A silica-supported zirconium based solid acid (ZS) has been used as catalyst for the Fries rearrangement of phenyl acetate (PA). The catalyst showed a higher PA conversion activity and a much higher selectivity for o-hydroxyacetophenone (o-HAP) than for strongly acidic zeolite catalysts. The supported catalyst was characterized by XRD,IR,XPS,pyridine-TPD and the surface area measurements. The catalytic properties were influenced significantly by pretreatment temperature.

  15. Solid-Phase Organic Synthesis and Catalysis: Some Recent Strategies Using Alumina, Silica, and Polyionic Resins

    Basudeb Basu


    Full Text Available Solid-phase organic synthesis (SPOS and catalysis have gained impetus after the seminal discovery of Merrifield’s solid-phase peptide synthesis and also because of wide applicability in combinatorial and high throughput chemistry. A large number of organic, inorganic, or organic-inorganic hybrid materials have been employed as polymeric solid supports to promote or catalyze various organic reactions. This review article provides a concise account on our approaches involving the use of (i alumina or silica, either having doped with metal salts or directly, and (ii polyionic resins to either promote various organic reactions or to immobilize reagents/metal catalysts for subsequent use in hydrogenation and cross-coupling reactions. The reaction parameters, scopes, and limitations, particularly in the context of green chemistry, have been highlighted with pertinent approaches by other groups.


    Lee, S.


    The objective of the present work is to model the resin particles within the column during fluidization and sedimentation processes using computation fluid dynamics (CFD) approach. The calculated results will help interpret experimental results, and they will assist in providing guidance on specific details of testing design and establishing a basic understanding of particle’s hydraulic characteristics within the column. The model is benchmarked against the literature data and the test data (2003) conducted at Savannah River Site (SRS). The paper presents the benchmarking results and the modeling predictions of the SRS resin column using the improved literature correlations applicable for liquid-solid granular flow.

  17. Solid Catalysts and theirs Application in Biodiesel Production

    Ramli Mat


    Full Text Available The reduction of oil resources and increasing petroleum price has led to the search for alternative fuel from renewable resources such as biodiesel. Currently biodiesel is produced from vegetable oil using liquid catalysts. Replacement of liquid catalysts with solid catalysts would greatly solve the problems associated with expensive separation methods and corrosion problems, yielding to a cleaner product and greatly decreasing the cost of biodiesel production. In this paper, the development of solid catalysts and its catalytic activity are reviewed. Solid catalysts are able to perform trans-esterification and esterification reactions simultaneously and able to convert low quality oils with high amount of Free Fatty Acids. The parameters that effect the production of biodiesel are discussed in this paper. Copyright © 2012 by BCREC UNDIP. All rights reservedReceived: 6th April 2012, Revised: 24th October 2012, Accepted: 24th October 2012[How to Cite: R. Mat, R.A. Samsudin, M. Mohamed, A. Johari, (2012. Solid Catalysts and Their Application in Biodiesel Production. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 142-149. doi:10.9767/bcrec.7.2.3047.142-149] [How to Link / DOI: ] | View in 

  18. Selective production of aromatics from alkylfurans over solid acid catalysts

    Wang, Dong; Dumesic, James A.; Taarning, Esben


    Solid acid catalysts were studied at temperatures near 523K for the production of benzene, toluene, and p-xylene by the reaction of ethylene with furan, 2-methylfuran, and 2,5-dimethylfuran, respectively, through the combination of cycloaddition and dehydrative aromatization reactions. Catalysts ...... that the high reactivity of WOx-ZrO2 is mainly associated with the presence of subnanometer WOx clusters mixed with zirconium, which reach a maximum surface concentration at intermediate tungsten coverage....

  19. Resin-Supported Catalysts for CuAAC Click Reactions in Aqueous or Organic Solvents

    Presolski, Stanislav I.; Mamidyala, Sreeman K.; Manzenrieder, Florian


    The copper-catalyzed azide-alkyne cycloaddition click reaction is a valuable process for the synthesis of libraries of drug candidates, derivatized polymers and materials, and a wide variety of other functional molecules. In some circumstances, the removal of the copper catalyst is both necessary and inconvenient. We describe here two immobilized forms of a Cu-binding ligand that has been shown to accelerate triazole formation under many different conditions, using different resin supports that are appropriate for aqueous or organic solvents. Copper leaching from these resins was modest, allowing them to be reused in many reaction/filtration cycles without recharging with metal ion. The utility of this catalyst form was demonstrated in the convenient synthesis of 20 N-acetylgalactosamine derivatives for biological testing. PMID:22946559

  20. Towards the computational design of solid catalysts

    Nørskov, Jens Kehlet; Bligaard, Thomas; Rossmeisl, Jan


    Over the past decade the theoretical description of surface reactions has undergone a radical development. Advances in density functional theory mean it is now possible to describe catalytic reactions at surfaces with the detail and accuracy required for computational results to compare favourably...... with increased activity and catalysts with improved selectivity. We discuss how, in the future, such methods may be used to engineer the electronic structure of the active surface by changing its composition and structure....

  1. Used solid catalysts from chemical and petrochemical industries; Les catalyseurs solides uses de l`industrie chimique et du raffinage petrolier



    A comprehensive survey of the solid catalysts used in the chemical and petrochemical industries is presented; information on solid catalyst market demand prospective for 1998, the nature of solid catalysts used in the various industrial sectors and for the various chemical products production, the european catalysts manufacturers, solid catalyst poisons and inhibitors according to the various types of chemical reactions, mean compositions of used solid catalysts, an assessment of the volume of used solid catalysts generated by chemical and petrochemical industries, the various ways of solid catalyst regeneration and disposal, the potential for off-site regeneration of used catalysts, and French and European regulations, is presented

  2. Environmentally Benign Bifunctional Solid Acid and Base Catalysts

    Elmekawy, A.; Shiju, N.R.; Rothenberg, G.; Brown, D.R.


    Solid bifunctional acid-​base catalysts were prepd. in two ways on an amorphous silica support: (1) by grafting mercaptopropyl units (followed by oxidn. to propylsulfonic acid) and aminopropyl groups to the silica surface (NH2-​SiO2-​SO3H)​, and (2) by grafting only aminopropyl groups and then parti

  3. One Step Preparation of Sulfonated Solid Catalyst and Its Effect in Esterification Reaction

    康世民; 常杰; 范娟


    A carbon-based sulfonated catalyst was prepared by direct sulfonation and carbonization (in moderate conditions:200 °C, 12 h) of red liquor solids, a by-product of paper-making process. The prepared sulfonated cata-lyst (SC) had aromatic structure, composed of carbon enriched inner core, and oxygen-containing (SO3H, COOH, OH) groups enriched surface. The SO3H, COOH, OH groups amounted to 0.74 mmol·g-1, 0.78 mmol·g-1, 2.18 mmol·g-1, respectively. The fresh SC showed much higher catalytic activity than that of the traditional solid acid catalysts (strong-acid 732 cation exchange resin, hydrogen type zeolite socony mobile-five (HZSM-5), sulfated zir-conia) in esterification of oleic acid. SC was deactivated during the reactions, through the mechanisms of leaching of sulfonated species and formation of sulfonate esters. Two regeneration methods were developed, and the catalytic activity can be mostly regenerated by regeneration Method 1 and be fully regenerated by regeneration Method 2, respectively.

  4. Esterification of Palmitic Acid with Methanol in the Presence of Macroporous Ion Exchange Resin as Catalyst

    Amelia Qarina Yaakob and Subhash Bhatia


    Full Text Available The esterification of palmitic acid with methanol was studied in a batch reactor using macro porous ion exchange resin Amberlyst 15 as a catalyst. Methyl palmitate was produced from the reaction between palmitic acid and methanol in the presence of catalyst. The effects of processing parameters, molar ratio of alcohol to acid M, (4-10, catalyst loading (0-10 g cat/liter, water inhibition (0-2 mol/liter, agitator speed (200-800 rpm and reaction temperature (343-373K were studied. The experimental kinetic data were correlated using homogenous as well as heterogeneous models (based on single as well as dual site mechanisms. The activation energy of the reaction was 11.552 kJ/mol for forward reaction whilst 5.464 kJ/mol for backward reaction. The experimental data fitted well with the simulated data obtained from the kinetic models. Keywords: Palmitic Acid, Methanol, Esterification, Ion Exchange Resin, Kinetics.

  5. Comparative evaluation of four trityl-type amidomethyl polystyrene resins in Fmoc solid phase peptide synthesis.

    Zikos, Christos; Livaniou, Evangelia; Leondiadis, Leondios; Ferderigos, Nikolas; Ithakissios, Dionyssis S; Evangelatos, Gregory P


    Four trityl-type (i.e. non-substituted trityl-, o-Cl-trityl-, o-F-trityl- and p-CN-trityl-) amidomethyl polystyrene resins were evaluated comparatively, in terms of the stability of the trityl-ester bond in slightly acidic dichloromethane solutions, and the p-CN-trityl-amidomethyl polystyrene resin was found to be the most stable of them. The above resins were applied, in parallel with Wang benzyl-type resin, well known for its stability in mild acidic conditions, to the Fmoc solid phase synthesis of the 43-amino acid residue long bioactive peptide thymosin beta-4. Independent of their differences in acid sensitivity, the resins seemed to function equally well under the conditions used, since pure thymosin beta-4 was obtained with a final yield of approximately 30% from each resin. The trityl-type amidomethyl polystyrene resins were also applied, in parallel with the Wang resin, to the Fmoc solid phase synthesis of a bioactive peptide containing proline at its C-terminus, i.e. the N-terminal tetrapeptide of thymosin beta-4, AcSDKP. In this case, the best yield (87%) was obtained with the o-Cl-trityl-amidomethyl polystyrene resin, which may be the resin of choice, of those studied, for the Fmoc solid phase peptide synthesis.

  6. Calcined sodium silicate as solid base catalyst for biodiesel production

    Guo, Feng; Peng, Zhen-Gang; Dai, Jian-Ying; Xiu, Zhi-Long [Department of Bioscience and Biotechnology, School of Environmental and Biological Science and Technology, Dalian University of Technology, Dalian 116024 (China)


    This paper examined the use of calcined sodium silicate as a novel solid base catalyst in the transesterification of soybean oil with methanol. The calcined sodium silicate was characterized by DTA-TG, Hammett indicator method, XRD, SEM, BET, IR and FT-IR. It catalyzed the transesterification of soybean oil to biodiesel with a yield of almost 100% under the following conditions: sodium silicate of 3.0 wt.%, a molar ratio of methanol/oil of 7.5:1, reaction time of 60 min, reaction temperature of 60 C, and stirring rate of 250 rpm. The oil containing 4.0 wt.% water or 2.5 wt.% FFA could also be transesterified by using this catalyst. The catalyst can be reused for at least 5 cycles without loss of activity. (author)

  7. Effect of toughened epoxy resin on partial discharge at solid-solid interface

    Manping, Li; Kai, Wu; Zhao, Zhang; Yonghong, Cheng


    A series of solid-solid interfaces, consisting of ceramic-epoxy resin interface samples with a tip-plate electrode, were investigated by performing partial discharge tests and real-time electrical tree observations. A toughening agent was added to the epoxy resin at different ratios for comparison. The impact strength, differential scanning calorimetry (DSC) and dielectric properties of the cured compositions and ceramic were tested. The electric field strength at the tip was calculated based on Maxwell’s theory. The test results show that the addition of a toughener can improve the impact strength of epoxy resin but it decreases the partial discharge inception voltage (PDIV) of the interface sample. At the same time, toughening leads to complex branches of the electrical tree. The simulation result suggests that this reduction of the PDIV cannot be explained by a change of permittivity due to the addition of a toughening agent. The microstructural change caused by toughening was considered to be the key factor for lower PDIV and complex electrical tree branches. Supported by China Academy of Engineering Physics (Project 2014B05005).

  8. Improved and selective platinum recovery from spent alpha-alumina supported catalysts using pretreated anionic ion exchange resin.

    Shams, K; Goodarzi, F


    Improved and selective recovery of platinum from a spent dehydrogenation platinum alpha-alumina supported catalyst using a strong basic ion exchange resin is reported. Platinum and other precious metal group (PMG) complexes are leached using concentrated hydrochloric acid along with about 0.20 vol.% nitric acid as an oxidizing agent from de-coked and crushed spent catalyst. Effects of hydrochloric acid concentration, time, and temperature in leaching stage are investigated. The strong basic anionic resin is treated by sodium hydroxide solution to replace chloride anion by hydroxyl group ion. The supernatant of the leaching process is passed through a fixed column of hydroxylated strong base anionic resin. The treated resin on which the platinum complex is adsorbed is dried and burned in an oxidizing atmosphere at 750-800 degrees C. The recovered gray metallic powder is mainly platinum. Results compared with those obtained from untreated anionic resin show that adsorption of platinum complexes onto the treated anionic resin is more selective and the yield of separation is considerably improved. The breakthrough curves of the pretreated anion exchanger and that of untreated exchange resin reveals that the capacity of the hyroxilated resin is decreased by about 14%. These breakthrough curves can be used for calculation of height of a practical exchange plate (HPEP) for design purposes.



    IntroductionMixed oxides and oxide-supported metalcatalysts are widely used in the petroleum andchemical industries. Besides aGtivity and selectivity, asuccessful solid catalyst should have good physicalproperties, among which mechanical strength is one ofthe key parameters for the reliable and efficientperformance of a fi'xed bed converterlll. Duringtransportation as well as in operation, the catalystssuffer from mechanical stress, which can besufficiently high to cause fracture of the particle. Theformati...

  10. Highly active, recyclable catalyst for the manufacture of viscous, low molecular weight, CO–ethene–propene-based polyketone, base component for a new class of resins

    Broekhuis, Antonius A.; Dirkzwager, Hendrik; Mul, Wilhelmus P.; Heeres, Hero J.; Linden, Adrianus J. van der; Orpen, A. Guy


    A highly active, recyclable homogeneous palladium(II) catalyst is described for the manufacture of viscous, low molecular weight CO–ethene–propene-based polyketone (Carilite Oligomer), used for the manufacture of a new class of resins (Carilite Resins). The catalyst is composed of palladium acetate,

  11. Sensitivity of catalyst/base ratio on curing of resin luting agents: polymerization exotherm analysis.

    Griggs, J A; Shen, C; Anusavice, K J


    Currently, the proposed test of the International Standardization Organization (ISO) for measuring working and setting times of resin luting agents is based on measurement of times to reach specified stages on the polymerization exotherm. The objective of this study was to use this test to investigate the influence of variations in the mass ratios of catalyst paste to base paste on the working and setting times of three dual-cured dental resin luting agents. The materials used were Dicor Light Activated Cement (Dentsply International Inc.), Palfique Inlay Resin Cement (Tokuyama Soda Co.), and Vivadent Dual Cement (Vivadent). Fifteen specimens of each material were tested for working time by spatulating mass ratios from 0.7 to 1.3 for 30s at 23 degrees C and recording the time from beginning of spatulation to the time at which a temperature increase occurs. Ten specimens of each material were tested for setting time by spatulating in a similar manner at 37 degrees C and recording the time at which the temperature reaches a maximum value. The data were fitted to the relation, In t = In A + Bm, where t is the time in seconds, m is the mass ratio, and A and B are regression coefficients. The results suggest that working and setting times of the specimens were independent of variations in mass ratio. A comparison among the materials was made by using a multiple linear regression with the relation, In t = In C + Dm + E gamma + Fm gamma, where gamma is a dummy variable to help distinguish between materials, and C, D, E, and F are regression coefficients. The results suggest that differences in materials influence the working time but not the setting time. These results infer that variations in mass ratio (+/- 20%) often observed in the clinical setting should not have a significant influence on the working and setting times of resin luting agents.

  12. Starch saccharification by carbon-based solid acid catalyst

    Yamaguchi, Daizo; Hara, Michikazu


    The hydrolysis of cornstarch using a highly active solid acid catalyst, a carbon material bearing SO 3H, COOH and OH groups, was investigated at 353-393 K through an analysis of variance (ANOVA) and an artificial neural network (ANN). ANOVA revealed that reaction temperature and time are significant parameters for the catalytic hydrolysis of starch. The ANN model indicated that the reaction efficiency reaches a maximum at an optimal condition (water, 0.8-1.0 mL; starch, 0.3-0.4 g; catalyst, 0.3 g; reaction temperature, 373 K; reaction time, 3 h). The relationship between the reaction and these parameters is discussed on the basis of the reaction mechanism.

  13. Synthesis and Structure Characterization of Phenol-Urea-Formaldehyde Resins in the Presence of Magnesium Oxide as Catalyst

    Dong-Bin Fan


    Full Text Available The objective of this research was to provide a useful approach of polymer synthesis for accelerating the fast cure of phenol-urea-formaldehyde (PUF resin as wood adhesive by optimizing its structure and composition. The PUF resins containing high contents of very reactive groups such as para-methylol groups were synthesized by reacting methylolurea, phenol, and formaldehyde in the presence of magnesium oxide (MgO as catalyst. The effects of synthesis parameters including F/(P + U, OH/P, and MgO/P mole ratios on the structure, composition, curing characteristics, and their relationships of PUF resins were investigated. The results indicated that MgO seemed to be an efficacious catalyst for PUF resin synthesis and promote its faster cure. The increase in the F/(P + U mole ratio or/and OH/P mole ratio appeared to be beneficial for the formation of para-methylol groups and cocondensed methylene linkages between phenolic methylol groups and urea units, and for the removal of unreacted urea. In case of Catalyst/P mole ratio, an appropriate dosage of added metal-ion was very important for synthesizing the high-content reactive groups of PUF resins, otherwise leading to the reverse effects.




    2-Hydroxyethyl acrylate is synthesized from acrylic acid and ethylene glycol under a simple and mild condition by using strong acidic cation ion exchange resin as a catalyst,which could be recycled as long as 10 times with high activation.

  15. Application of solid phase microextraction on dental composite resin analysis.

    Wang, Ven-Shing; Chang, Ta-Yuan; Lai, Chien-Chen; Chen, San-Yue; Huang, Long-Chen; Chao, Keh-Ping


    A direct immersion solid phase microextraction (DI-SPME) method was developed for the analysis of dentin monomers in saliva. Dentine monomers, such as triethylene glycol dimethacrylate (TEGDMA), urethane dimethacrylate (UDMA) and 2,2-bis-[4-(2-hydroxy-3-methacryloyloxypropoxy) phenyl]-propane (Bis-GMA), have a high molecular weight and a low vapor pressure. The polydimethylsiloxane/divinylbenzene (PDMS/DVB) fiber with a medium polarity was employed for DI-SPME, and 215 nm of detection wavelength was found to be optimum in the chromatogram of HPLC measurement. The calibration range for DI-SPME was 0.30-300 μg/mL with correlation coefficients (r) greater than 0.998 for each analyte. The DI-SPME method achieved good accuracy (recovery 96.1-101.2%) and precision (2.30-8.15% CV) for both intra- and inter-day assays of quality control samples for three target compounds. Method validation was performed on standards dissolved in blank saliva, and there was no significant difference (p>0.2) between the DI-SPME method and the liquid injection method. However, the detection limit of DI-SPME was as low as 0.03, 0.27 and 0.06 μg/mL for TEGDMA, UDMA and Bis-GMA, respectively. Real sample analyses were performed on commercial dentin products after curing for the leaching measurement. In summary, DI-SPME is a more sensitive method that requires less sample pretreatment procedures to measure the resin materials leached in saliva.

  16. Aldol Condensation of Citral with Acetone on Basic Solid Catalysts

    NODA C.


    Full Text Available The catalytic performance of solids with basic properties, such as CaO, MgO and hydrotalcites, was evaluated in the aldol condensation of citral and acetone, the first step in the synthesis of ionones from citral. The best results were obtained with CaO and hydrotalcite with high conversions (98% and selectivities (close to 70% for the main product observed for both of the catalyst. Such pseudoionone yields were greater than those reported in the literature for the homogeneous reaction.

  17. Controllable core-shell-type resin for solid-phase peptide synthesis.

    Cho, Hong-Jun; Lee, Tae-Kyung; Kim, Jung Won; Lee, Sang-Myung; Lee, Yoon-Sik


    A simple, mild, and inexpensive biphasic functionalization approach is attempted for preparing an ideal core-shell-type resin. The core-shell-type architecture was constructed by coupling Fmoc-OSu to the amino groups on the shell layer of an aminomethyl polystyrene (AM PS) resin. The shell layer thickness of the resin could be easily controlled under mild conditions, which was characterized by confocal laser scanning microscopy (CLSM). The efficiency of core-shell-type resin for solid-phase peptide synthesis (SPPS) was demonstrated by the synthesis of various peptides and compared with commercially available noncore-shell-type resins such as AM PS and poly(ethylene glycol)-based resins. The core-shell-type resin provided effective performance during the synthesis of hydrophobic peptide sequences, a disulfide-bridged cyclic peptide, and a difficult PNA sequence. Furthermore, a highly aggregative peptide fragment, MoPrP 105-125, was synthesized more efficiently on the core-shell-type resin under microwave conditions than AM PS and ChemMatrix resins.

  18. Imidazolium Ionic Liquid Modified Graphene Oxide: As a Reinforcing Filler and Catalyst in Epoxy Resin

    Qing Lyu


    Full Text Available Surface modification of graphene oxide (GO is one of the most important issues to produce high performance GO/epoxy composites. In this paper, the imidazole ionic liquid (IMD-Si was introduced onto the surface of GO sheets by a cheap and simple method, to prepare a reinforcing filler, as well as a catalyst in epoxy resin. The interlayer spacing of GO sheets was obviously increased by the intercalation of IMD-Si, which strongly facilitated the dispersibility of graphene oxide in organic solvents and epoxy matrix. The addition of 0.4 wt % imidazolium ionic liquid modified graphene oxide (IMD-Si@GO, yielded a 12% increase in flexural strength (141.3 MPa, a 26% increase in flexural modulus (4.69 GPa, and a 52% increase in impact strength (18.7 kJ/m2, compared to the neat epoxy. Additionally the IMD-Si@GO sheets could catalyze the curing reaction of epoxy resin-anhydride system significantly. Moreover, the improved thermal conductivities and thermal stabilities of epoxy composites filled with IMD-Si@GO were also demonstrated.

  19. Metal Organic Frameworks as Solid Catalysts in Condensation Reactions of Carbonyl Groups

    Dhakshina Moorthy, Amarajothi; Opanasenko, Maksym; Cejka, Jirí; García Gómez, Hermenegildo


    This review summarizes the use of metal organic frameworks (MOFs) as solid catalysts for condensation reactions. After an introductory section, in which condensation reactions are generally presented, a list of the MOFs employed as condensation catalyst is given. The main part of the present review is organized according to the use of MOFs as solid acids, solid bases or as bi-functional solids containing both acid and basic sites. Throughout the review, the emphasis has been made on discussin...

  20. A development of the stabilization technology for the solid form of ion exchange resin

    Kim, T. K.; Lee, Y. H.; Kang, I. S.; Bae, S. M; Ahn, S. J.; Lee, K. M.; Kim, K. J.; Son, J. S.; Hong, K. P. [KAERI, Taejon (Korea, Republic of)


    In this study, a modified bituminization technology has been developed, which needs no grinding of the granular resin waste, and enables the solid form to keep its shape stability as good as that of a cemented solid form. Also, the study intended to apply the developed technology to the practical treatment of radioactive resin waste. In the experiment, the granular type resin was used and the straight-run distillation bitumen with penetration rate 60/70 was used as the solidifying agent. The PE was used as the additive. The shape stability increased remarkably with the additive of PE, which act as a binder in the solid form. The shape of the solid form was maintained without failure during the long-term exposure test when the additive content of spent PE is more than 10wt %. The proper ranges of bitumen content, PE content and operating temperature are 30-50wt%, 10-20wt% and 180 .deg. C respectively. The bituminized solid form of radioactive resin waste by the technology of this study has the remarkably superior quality than the conventional solid forms, partially for the shape stability.

  1. Impeded solid state reactions and transformations in ceramic catalysts supports and catalysts

    Ernő E. Kiss


    Full Text Available Impeded chemical reactions and impeded polymorphous transformation in materials are discussed, as desired effects, for stabilization of ceramic catalyst supports and ceramic based catalysts. This paper gives a short overview about the possibilities of slowing down the aging processes in ceramic catalyst supports and catalysts. Special attention is given to alumina and titania based catalysts.

  2. Active carbon-ceramic sphere as support of ruthenium catalysts for catalytic wet air oxidation (CWAO) of resin effluent.

    Liu, Wei-Min; Hu, Yi-Qiang; Tu, Shan-Tung


    Active carbon-ceramic sphere as support of ruthenium catalysts were evaluated through the catalytic wet air oxidation (CWAO) of resin effluent in a packed-bed reactor. Active carbon-ceramic sphere and ruthenium catalysts were characterized by N(2) adsorption and chemisorption measurements. BET surface area and total pore volume of active carbon (AC) in the active carbon-ceramic sphere increase with increasing KOH-to-carbon ratio, and AC in the sample KC-120 possesses values as high as 1100 m(2) g(-1) and 0.69 cm(3) g(-1) (carbon percentage: 4.73 wt.%), especially. Active carbon-ceramic sphere supported ruthenium catalysts were prepared using the RuCl(3) solution impregnation onto these supports, the ruthenium loading was fixed at 1-5 wt.% of AC in the support. The catalytic activity varies according to the following order: Ru/KC-120>Ru/KC-80>Ru/KC-60>KC-120>without catalysts. It is found that the 3 wt.% Ru/KC-120 catalyst displays highest stability in the CWAO of resin effluent during 30 days. Chemical oxygen demand (COD) and phenol removal were about 92% and 96%, respectively at the reaction temperature of 200 degrees C, oxygen pressure of 1.5 MPa, the water flow rate of 0.75 L h(-1) and the oxygen flow rate of 13.5 L h(-1).

  3. Synthesis of Resins with Chiral Salen Complexes


    @@ The enormous growth in the use of polymer resin supports in solid phase combinatorial synthesis, and related methodologies, has re-stimulated interest in the area of polymer-supported transition metal complex catalyst .The recently developed chiral salen-based for the enantioselective ring opening of meso epoxides and kinetic resolution of terminal epoxides are appealing candidates for immobilization on solid support. The catalysts are reading prepare from inexpensive components, and are amenable to modification for attachment to a solid support.


    Wen-xi Cheng; Li-ya Shi; Shi-yun Li; Hui Chen; Tao Tang


    The possibility of mesoporous acid solid as a carrier for metallocene catalyst in ethylene polymerization and catalyst for polyethylene(PE)catalytic degradation was investigated.Here,HMCM-41 and AlMCM-41.and mesoporous silicoaluminophosphate molecular sieves(SAPO1 and SAPO2)were synthesized and used as acid solid.Much more gases were produced during catalytic degradation in PE/acid solid mixtures via in situ polymerization than those via physical mixing.The particle size distribution results exhibited that the particle size of SAPO1 in the PE/SAO1 mixture via in situ polymerization was about 1/14 times of that of the original SAPO1 or SAPO1.supported metallocene catalyst.This work shows a novel technology for chemical recycling of polyolefin.

  5. A convenient procedure for the solid-phase synthesis of hydroxamic acids on PEGA resins

    Nandurkar, Nitin Subhash; Petersen, Rico; Qvortrup, Katrine


    An efficient method for the solid-phase synthesis of hydroxamic acids is described. The method comprises the nucleophilic displacement of esters immobilized on PEGA resins with hydroxylamine/sodium hydroxide in isopropanol. The hydroxyaminolysis protocol is compatible with a broad range of PEGA-s...

  6. Linkers, resins, and general procedures for solid-phase peptide synthesis

    Shelton, Anne Pernille Tofteng; Jensen, Knud Jørgen


    and linkers for solid-phase synthesis is a key parameter for successful peptide synthesis. This chapter provides an overview of the most common and useful resins and linkers for the synthesis of peptides with C-terminal amides, carboxylic acids, and more. The chapter finishes with robust protocols for general...

  7. Novel, benign, solid catalysts for the oxidation of hydrocarbons.

    Ratnasamy, Paul; Raja, Robert; Srinivas, Darbha


    The catalytic properties of two classes of solid catalysts for the oxidation of hydrocarbons in the liquid phase are discussed: (i) microporous solids, encapsulating transition metal complexes in their cavities and (ii) titanosilicate molecular sieves. Copper acetate dimers encapsulated in molecular sieves Y, MCM-22 and VPI-5 use dioxygen to regioselectively ortho-hydroxylate L-tyrosine to L-dopa, phenol to catechol and cresols to the corresponding o-dihydroxy and o-quinone compounds. Monomeric copper phthalocyanine and salen complexes entrapped in zeolite-Y oxidize methane to methanol, toluene to cresols, naphthalene to naphthols, xylene to xylenols and phenol to diphenols. Trimeric mu3-oxo-bridged Co/Mn cluster complexes, encapsulated inside Y-zeolite, oxidize para-xylene, almost quantitatively, to terephthalic acid. In almost all cases, the intrinsic catalytic activity (turnover frequency) of the metal complex is enhanced very significantly, upon encapsulation in the porous solids. Spectroscopic and electrochemical studies suggest that the geometric distortions of the complex on encapsulation change the electron density at the metal ion site and its redox behaviour, thereby influencing its catalytic activity and selectivity in oxidation reactions. Titanosilicate molecular sieves can oxidize hydrocarbons using dioxygen when loaded with transition metals like Pd, Au or Ag. The structure of surface Ti ions and the type of oxo-Ti species generated on contact with oxidants depend on several factors including the method of zeolite synthesis, zeolite structure, solvent, temperature and oxidant. Although, similar oxo-Ti species are present on all the titanosilicates, their relative concentrations vary among different structures and determine the product selectivity.

  8. The effect of curing light and chemical catalyst on the degree of conversion of two dual cured resin luting cements.

    Souza-Junior, Eduardo José; Prieto, Lúcia Trazzi; Soares, Giulliana Panfiglio; Dias, Carlos Tadeu dos Santos; Aguiar, Flávio Henrique Baggio; Paulillo, Luís Alexandre Maffei Sartini


    The aim of this study was to evaluate the influence of different curing lights and chemical catalysts on the degree of conversion of resin luting cements. A total of 60 disk-shaped specimens of RelyX ARC or Panavia F of diameter 5 mm and thickness 0.5 mm were prepared and the respective chemical catalyst (Scotchbond Multi-Purpose Plus or ED Primer) was added. The specimens were light-cured using different curing units (an argon ion laser, an LED or a quartz-tungsten-halogen light) through shade A2 composite disks of diameter 10 mm and thickness 2 mm. After 24 h of dry storage at 37°C, the degree of conversion of the resin luting cements was measured by Fourier-transformed infrared spectroscopy. For statistical analysis, ANOVA and the Tukey test were used, with p ≤ 0.05. Panavia F when used without catalyst and cured using the LED or the argon ion laser showed degree of conversion values significantly lower than RelyX ARC, with and without catalyst, and cured with any of the light sources. Therefore, the degree of conversion of Panavia F with ED Primer cured with the quartz-tungsten-halogen light was significantly different from that of RelyX ARC regardless of the use of the chemical catalyst and light curing source. In conclusion, RelyX ARC can be cured satisfactorily with the argon ion laser, LED or quartz-tungsten-halogen light with or without a chemical catalyst. To obtain a satisfactory degree of conversion, Panavia F luting cement should be used with ED Primer and cured with halogen light.

  9. VQS (vapor-quasiliquid-solid, vapor-quasisolid-solid) mechanism for the catalyst-free and catalyst-mediated non-eutectic syntheses of single-crystal nanowires

    Noor Mohammad, S.


    Catalyst-free and catalyst-assisted nanowire (NW) syntheses are increasingly carried out by mechanism(s) other than the well-known VLS (vapor-liquid-solid) mechanism. Yet these growths are not fully understood. An in-depth investigation has been carried out to understand the mechanism of the catalyst-free and catalyst-mediated non-VLS NW growths. Various chemical and physical processes involved in these growths have been studied to formulate general principles. Phase transitions, synthesis routes, and the fundamentals underlying these routes have been explored. Nanoparticle surfaces conducive to NW syntheses have been examined. The role of surface treatment, such as oxidation, oxygenation, doping, acid treatment, plasma treatment, etc., in creating such surfaces has been elucidated. Surface treatment and phase transition under appropriate growth conditions (temperature, pressure, ambient, and the presence of contaminants) have been found to be important. They play a crucial role in creating diffusion paths for the diffusion of the growth species for NW growths. Interdiffusion of the catalyst and the growth species on the nanoparticle surface has been found also to add a new dimension to the growth kinetics. When integrated together, they create a unified platform versatile enough to explain essentially all catalyst-free and catalyst-mediated non-eutectic NW growths. The platform uncovers numerous growth-related problems never understood before. Available experiments extensively support this platform. These experiments suggest that it is based on solid foundation and has broad and probably universal appeal. It pertains to the vapor-quasiliquid-solid, vapor-quasi-solid-solid mechanism proposed some six years ago.

  10. Review of the Production of Biodiesel from Waste Cooking Oil using Solid Catalysts

    N.H. Said


    Full Text Available The need for fossil fuels and the emissions generated from these fuels are increasing daily. Researchers are concerned with global warming as well as climate change; and energy sustainability and material usages are important issues today. Waste cooking oil (WCO can be processed into biodiesel as an alternative fuel to replace diesel. Production of biodiesel using WCO as the feedstock has been of growing interest for the last two decades. A number of research papers related to the improvements in production, raw materials and catalyst selection have been published. This paper reviews the various types of heterogeneous solid catalyst in the production of biodiesel via the transesterification of WCO. The catalysts used can be classified according to their state presence in the transesterification reaction as homogeneous or heterogeneous catalysts. Homogeneous catalysts act in the same liquid phase as the reaction mixture, whereas heterogeneous catalysts act in a solid phase with the reaction mixture. Heterogeneous catalysts are non-corrosive, a green process and environmentally friendly. They can be recycled and used several times, thus offering a more economic pathway for biodiesel production. The advantages and drawbacks of these heterogeneous catalysts are presented. Future work focuses on the application of economically and environmentally friendly solid catalysts in the production of biodiesel using WCO as the raw material.

  11. Kl-impregnated Oyster Shells as a Solid Catalyst for Soybean Oil Transesterificaton

    Research on inexpensive and green catalysts is needed for economical production of biodiesel. The goal of the research was to test KI-impregnated oyster shell as a solid catalyst for transesterification of soybean oil. Specific objectives were to characterize KI-impregnated oyster shell, determine t...

  12. Direct transformation of carbohydrates to the biofuel 5-ethoxymethylfurfural by solid acid catalysts

    Li, Hu; Shunmugavel, Saravanamurugan; Yang, Song;


    The direct conversion of glucose to 5-ethoxymethylfurfural (EMF) is a promising biomass transformation due to the products potential application as a biofuel. Here, the conversion of glucose to EMF was examined over several solid acid catalysts in ethanol between 96 and 125 oC. Among the catalyst...

  13. Calcium oxide as a solid base catalyst for transesterification of soybean oil and its application to biodiesel production

    Masato Kouzu; Takekazu Kasuno; Masahiko Tajika; Yoshikazu Sugimoto; Shinya Yamanaka; Jusuke Hidaka [Keihanna Interaction Plaza Inc., Kyoto (Japan). JST-KFPT Core Research Center


    In order to study solid base catalyst for biodiesel production with environmental benignity, transesterification of edible soybean oil with refluxing methanol was carried out in the presence of calcium oxide (CaO), -hydroxide (Ca(OH){sub 2}), or -carbonate (CaCO{sub 3}). At 1 h of reaction time, yield of FAME was 93% for CaO, 12% for Ca(OH){sub 2}, and 0% for CaCO{sub 3}. Under the same reacting condition, sodium hydroxide with the homogeneous catalysis brought about the complete conversion into FAME. Also, CaO was used for the further tests transesterifying waste cooking oil (WCO) with acid value of 5.1 mg-KOH/g. The yield of FAME was above 99% at 2 h of reaction time, but a portion of catalyst changed into calcium soap by reacting with free fatty acids included in WCO at initial stage of the transesterification. Owing to the neutralizing reaction of the catalyst, concentration of calcium in FAME increased from 187 ppm to 3065 ppm. By processing WCO at reflux of methanol in the presence of cation-exchange resin, only the free fatty acids could be converted into FAME. The transesterification of the processed WCO with acid value of 0.3 mg-KOH/g resulted in the production of FAME including calcium of 565 ppm. 22 refs., 6 figs., 5 tabs.

  14. A Mini-Review on Solid Acid Catalysts for Esterification Reactions

    Sirsam, Rajkumar; Hansora, Dharmesh; Usmani, Ghayas A.


    This paper presents an overview of research pertaining to solid acid catalysts for esterification reactions. Prominence has been given to the literatures that have been appeared during the last two decades. A variety of reactions catalyzed by solid acid catalysts have been tabulated according to their broad classification; industrially important reactions have been outlined. Examples, where the use of various solid acid catalysts have led to an improvement in the selectivity of the desired products, have also been discussed. Various catalyzed esterification reactions using different approaches and previous kinetic studies have been reviewed. Types, preparation and synthesis of various solid acid catalysts have been reviewed and discussed. Suggestions have been summarized for their implementation in future work.

  15. Preparation of Pt/C Catalyst with Solid Phase Reaction Method


    The Pt/C catalyst was prepared with solid phase reaction method (Pt/C(S)) for the first time. Its performances were compared with that prepared by the traditional liquid phase reaction method. The results demonstrate that the electrocatalytic activity of Pt/C catalyst with solid phase reaction method for methanol oxidation is higher than that with liquid phase reaction method. XRD and TEM measurements indicate that the Pt/C(S) possesses low crystalline extent and small particle size.

  16. Conversion of furfuryl alcohol into ethyl levulinate using solid acid catalysts.

    Lange, Jean-Paul; van de Graaf, Wouter D; Haan, René J


    Furfural, a potential coproduct of levulinic acid, can be converted into levulinic acid via hydrogenation to furfuryl alcohol and subsequent ethanolysis to ethyl levulinate. The ethanolysis reaction is known to proceed in the presence of H(2)SO(4). We show here that several strongly acidic resins are comparably effective catalysts for this reaction. Optimal performance is achieved by balancing the number of acid sites with their accessibility in the resin. Acidic zeolites such as H-ZSM-5 also catalyze this reaction, although with a lower activity and a higher co-production of diethyl ether.

  17. Characterization of solid UV curable 3D printer resins for biological applications

    Sivashankar, Shilpa


    In this paper, we report a simple method to evaluate biocompatibility of solid UV cross-linked resin as a material for microfluidic devices that can be used for biological applications. We evaluated the biocompatibility of the material in two different ways (1) determining if the UV cured resin inhibits the polymerase chain reaction (PCR) and (2) observing agglutination complex formed on the surface of the UV cured resin when anti-CRP antibodies and C- reactive protein (CRP) proteins were allowed to agglutinate. Six different types of 3D printer resins were compared to test the biocompatibility. The study showed that only few among them could be used for fabrication of micro channels and that had least effect on biological molecules that could be used for PCR and protein interactions. Through these studies it is possible to estimate the curing time of various resin and their type of interaction with biomolecules. This study finds importance in on-chip tissue engineering and organ-on-chip applications.

  18. Solid Phase Synthesis of 1, 4-Disubstituted 1, 2, 3-Triazole from Polystyrene-supported Selenium Resin

    Wei Ming XU; Lu Ling WU; Xian HUANG


    We report here a solid-phase synthesis of 1, 4-disubstituted 1, 2, 3-triazole using polystyrene-supported selenium resin. The resin used here not only works as a simple linker, but also assists the crucial α-alkylation reaction and selenoxide syn-elimination, which ensures the purity of the products.

  19. Kinetics of germanium nanowire growth by the vapor-solid-solid mechanism with a Ni-based catalyst

    Shruti V. Thombare


    Full Text Available The kinetics of vapor-solid-solid (VSS Ge nanowire growth using a Ni-based catalyst were investigated to probe the rate-limiting step for this complex nanoscale crystal growth process. The effects of key parameters such as temperature and precursor partial pressure on the nanowire growth rate were studied in order to gain detailed insights into the growth kinetics. Two different regimes were observed for VSS growth of Ge nanowires as function of temperature. At higher temperatures (345 °C–375 °C, kinetics data suggest that mass transport of germane precursor to the catalyst surface is rate limiting. At lower temperatures (<345 °C, either surface reaction of the GeH4 precursor on the catalyst or incorporation of Ge into the nanowire across the wire/catalyst interface is rate limiting.

  20. Synthesis and characterization of novel solid base catalyst from fly ash

    Deepti Jain; Chitralekha Khatri; Ashu Rani [University of Kota, Rajasthan (India). Department of Pure and Applied Chemistry


    A new type of solid base catalyst was synthesized by chemical and thermal activation of fly ash, collected from Thermal Super Power Station situated in Kota, Rajasthan, India. The chemical activation was carried out by 50 wt.% NaOH followed by thermal activation at 450{sup o}C. The modified physiochemical property of solid base fly ash (SBFA) was determined by X-ray diffraction, FT-IR spectroscopy, Scanning Electron Microscopy, N{sub 2} adsorption-desorption studies and Flame Atomic Absorption Spectrophotometry. The results reveal that the catalyst is nano-crystalline in nature with crystallite size 11 nm and particle size in the range 840 nm to 6.95 {mu}m. The surface basicity and therefore, catalytic activity in SBFA was originated by increased hydroxyl content as compared to fly ash, suggesting that the catalyst possess higher surface active sites. The basicity of the catalyst was measured by liquid phase, solvent free, single step condensation of benzaldehyde with cyclohexanone giving higher conversion ({gt}70%) and selectivity ({gt}80%) of desired product a,a'-dibenzylidenecyclohexanone. This excellent conversion shows that the catalyst has sufficient basic sites both on the surface and in the bulk, responsible for the catalytic activity. Furthermore, this catalyst may replace conventional environmentally hazardous homogeneous liquid bases making an ecofriendly, solvent free, solid base catalyzed process. The application of fly ash to synthesize a solid base catalyst finds a noble way to utilize this abundant waste material. 26 refs., 5 figs., 2 tabs.

  1. Performance evaluation of commercial copper chromites as burning rate catalyst for solid propellants

    Milton Faria Diniz


    Full Text Available Copper chromites are well known as burning rate catalysts for the combustion of composite solid propellants, used as a source of energy for rocket propulsion. The propellant burning rate depends upon the catalyst characteristics such as chemical composition and specific surface area. In this work, copper chromite samples from different suppliers were characterized by chemical analysis, FT-IR spectroscopy and by surface area measurement (BET. The samples were then evaluated as burning rate catalyst in a typical composite propellant formulation based on HTPB binder, ammonium perchlorate and aluminum. The obtained surface area values are very close to those informed by the catalyst suppliers. The propellant processing as well as its mechanical properties were not substantially affected by the type of catalyst. Some copper chromite catalysts caused an increase in the propellant burning rate in comparison to the iron oxide catalyst. The results show that in addition to the surface area, other parameters like chemical composition, crystalline structure and the presence of impurities might be affecting the catalyst performance. All evaluated copper chromite samples may be used as burning rate catalyst in composite solid propellant formulations, with slight advantages for the SX14, Cu-0202P and Cu-1800P samples, which led to the highest burning rate propellants.

  2. Cu–Co–O nano-catalysts as a burn rate modifier for composite solid propellants

    D. Chaitanya Kumar Rao


    Full Text Available Nano-catalysts containing copper–cobalt oxides (Cu–Co–O have been synthesized by the citric acid (CA complexing method. Copper (II nitrate and Cobalt (II nitrate were employed in different molar ratios as the starting reactants to prepare three types of nano-catalysts. Well crystalline nano-catalysts were produced after a period of 3 hours by the calcination of CA–Cu–Co–O precursors at 550 °C. The phase morphologies and crystal composition of synthesized nano-catalysts were examined using Scanning Electron Microscope (SEM, Energy Dispersive Spectroscopy (EDS and Fourier Transform Infrared Spectroscopy (FTIR methods. The particle size of nano-catalysts was observed in the range of 90 nm–200 nm. The prepared nano-catalysts were used to formulate propellant samples of various compositions which showed high reactivity toward the combustion of HTPB/AP-based composite solid propellants. The catalytic effects on the decomposition of propellant samples were found to be significant at higher temperatures. The combustion characteristics of composite solid propellants were significantly improved by the incorporation of nano-catalysts. Out of the three catalysts studied in the present work, CuCo-I was found to be the better catalyst in regard to thermal decomposition and burning nature of composite solid propellants. The improved performance of composite solid propellant can be attributed to the high crystallinity, low agglomeration and lowering the decomposition temperature of oxidizer by the addition of CuCo-I nano-catalyst.

  3. Butyric acid esterification kinetics over Amberlyst solid acid catalysts: the effect of alcohol carbon chain length.

    Pappu, Venkata K S; Kanyi, Victor; Santhanakrishnan, Arati; Lira, Carl T; Miller, Dennis J


    The liquid phase esterification of butyric acid with a series of linear and branched alcohols is examined. Four strong cation exchange resins, Amberlyst™ 15, Amberlyst™ 36, Amberlyst™ BD 20, and Amberlyst™ 70, were used along with para-toluenesulfonic acid as a homogeneous catalyst. The effect of increasing alcohol carbon chain length and branching on esterification rate at 60°C is presented. For all catalysts, the decrease in turnover frequency (TOF) with increasing carbon chain length of the alcohol is described in terms of steric hindrance, alcohol polarity, and hydroxyl group concentration. The kinetics of butyric acid esterification with 2-ethylhexanol using Amberlyst™ 70 catalyst is described with an activity-based, pseudo-homogeneous kinetic model that includes autocatalysis by butyric acid.


    Wei Huang; Ying Huang; Yun-zhao Yu


    MQ silicone resins were prepared through hydrolytic condensation of ethyl polysilicate or tetraethoxysilane and hexamethyl disiloxane. The unit ratio of the MQ resins was determined by 29Si-NMR.The relationship of the unit ratio of the product resins with that in the feed was studied. When the reaction was catalyzed by aqueous hydrochloric acid, and the unit ratio of M to Q in the feed was more than 1, the unit ratio of the product was usually lower than that of the feed. The MQ silicon with an unit ratio of M/Q>2 could not be obtained. However, if the reaction was catalyzed by concentrated sulfuric acid and the reverse hydrolysis process was employed, MQ silicone resin with very high M/Q ratio was successfully prepared.

  5. Recycling asymmetric hydrogenation catalysts by their immobilisation onto ion-exchange resins.

    Barbaro, Pierluigi; Bianchini, Claudio; Giambastiani, Giuliano; Oberhauser, Werner; Bonzi, Laura Morassi; Rossi, Filippo; Dal Santo, Vladimiro


    New systems based on cationic chiral phosphine-rhodium complexes anchored to a commercial cation-exchange gel-type resin showed high efficiency and easy recycling in the asymmetric hydrogenation of prochiral olefins.

  6. Synthesis and application of monodisperse oligo(oxyethylene)-grafted polystyrene resins for solid-phase organic synthesis.

    Lumpi, Daniel; Braunshier, Christian; Horkel, Ernst; Hametner, Christian; Fröhlich, Johannes


    In a preliminary investigation by our group, we found that poly(styrene-oxyethylene) graft copolymers (PS-PEG), for example, TentaGel resins, are advantageous for gel-phase (13)C NMR spectroscopy. Because of the solution-like environment provided by the PS-PEG resins, good spectral quality of the attached moiety can be achieved, which is useful for nondestructive on-resin analysis. The general drawbacks of such resins are low loading capacities and the intense signal in the spectra resulting from the PEG linker (>50 units). Here, we describe the characterization of solvent-dependent swelling and reaction kinetics on a new type of resin for solid-phase organic synthesis (SPOS) that allows an accurate monitoring by gel-phase NMR without the above disadvantages. A series of polystyrene-oligo(oxyethylene) graft copolymers containing monodisperse PEG units (n = 2-12) was synthesized. A strong correlation between the linker (PEG) length and the line widths in the (13)C gel-phase spectra was observed, with a grafted PEG chain of 8 units giving similar results in terms of reactivity and gel-phase NMR monitoring to TentaGel resin. Multistep on-resin reaction sequences were performed to prove the applicability of the resins in solid-phase organic synthesis.

  7. Sodium phosphate as a solid catalyst for biodiesel preparation

    S. T. Jiang


    Full Text Available Sodium phosphate (Na3PO4 was chosen as catalyst for biodiesel preparation from rapeseed oil. The effects of mass ratio of catalyst to oil, molar ratio of methanol to oil, reaction temperature and rotation speed on biodiesel yield were investigated. For a mass ratio of catalyst to oil of 3%, molar ratio of methanol to oil of 9:1, reaction temperature of 343K and rotation speed of 600rpm, the transesterification was nearly completed within 20 minutes. Na3PO4 has a similar activity to homogeneous catalysts. Na3PO4 could be used repeatedly for 8 runs without any activation treatment and no obvious activity loss was observed. The concentrations of catalyst in biodiesel ranged from 0.6 to 0.7 mg/g. Compared to Na3PO4, Na3PO4.10H2O was cheaper, but the final yield was 71.3%, much lower than that of Na3PO4 at 99.7%.

  8. Modeling of Isobutane/Butene Alkylation Using Solid Acid Catalysts in a Fixed Bed Reactor

    Liu Zheng; Tang Xiaojin; Hu Lifeng; Hou Shuandi


    A dynamic mass transfer model of isobutane/butene alkylation over solid acid catalysts in a ifxed bed reactor was established. In the model, a modiifed equation for the relationship between point activity and effective diffusion coefifcient was proposed. It is found that the simulation results ift the experimental data well and the breakthrough time of the bed layer is predicted accurately. By modeling the alkylation process, the time-space distribution of butene and point activity proifles of catalysts can be obtained. Furthermore, the reasons for the deactivation of solid acid catalysts were investigated. It indicates that the main reason for the deactivation of catalysts is the site coverage near the inlet of the reactor, while it is ascribed to the steric effect in the region far away from the inlet.

  9. Production of furans from pulp sheet over sulfated solid acid catalysts

    Hongdan Zhang


    Full Text Available Furans are high value-added biomass-derived chemicals that can be used to replace petrochemicals. In this study, sulfated solid acid catalysts were prepared by precipitation and impregnation and were used for the conversion of a cellulosic pulp sheet into furans. The physicochemical properties of the prepared sulfated solid acid with different calcination temperatures and different mol ratios of Ti-Al were characterized using XRD, elemental analysis, TG, and NH3-TPD. Furthermore, the effects of various processing parameters such as temperature, time, and catalyst dosage on the reaction performance were studied. The combined yield of 5-hydroxymethyl-furfural and furfural reached 8.9% and 4.5% of pulp sheet mass with a 5% dosage of SO42-/TiO2-Al2O3 catalyst at 220 oC for 30 min. The activity for recovered catalyst was also investigated in this study.

  10. Aerobic Oxidation of 5-(Hydroxymethyl)furfural in Ionic Liquids with Solid Ruthenium Hydroxide Catalysts

    Ståhlberg, Tim Johannes Bjarki; Eyjolfsdottir, Ester; Gorbanev, Yury


    ][OAc] at 100 °C with 30 bar of oxygen over Ru(OH) x /La2O3 which afforded 48 % of 2,5-furandicarboxylic acid and 12 % of 5-hydroxymethyl-2-furancarboxylic acid. During use the catalysts were found to leach some of the metal inventory. However, the leached Ru species did not contribute to the catalytic activity......The aerobic oxidation of 5-(hydroxymethyl)furfural was investigated over solid ruthenium hydroxide catalysts in ionic liquids at elevated temperatures and pressures. Several different catalyst supports were tested in combination with various ionic liquids. The best result was obtained in [EMIm...

  11. A microalgae residue based carbon solid acid catalyst for biodiesel production.

    Fu, Xiaobo; Li, Dianhong; Chen, Jie; Zhang, Yuanming; Huang, Weiya; Zhu, Yi; Yang, Jun; Zhang, Chengwu


    Biodiesel production from microalgae is recognized as one of the best solutions to deal with the energy crisis issues. However, after the oil extraction from the microalgae, the microalgae residue was generally discarded or burned. Here a novel carbon-based solid acid catalyst derived from microalgae residue by in situ hydrothermal partially carbonization were synthesized. The obtained catalyst was characterized and subjected to both the esterification of oleic acid and transesterification of triglyceride to produce biodiesel. The catalyst showed high catalytic activity and can be regenerated while its activity can be well maintained after five cycles.

  12. Ceria-based solid catalysts for organic chemistry.

    Vivier, Laurence; Duprez, Daniel


    Ceria has been the subject of thorough investigations, mainly because of its use as an active component of catalytic converters for the treatment of exhaust gases. However, ceria-based catalysts have also been developed for different applications in organic chemistry. The redox and acid-base properties of ceria, either alone or in the presence of transition metals, are important parameters that allow to activate complex organic molecules and to selectively orient their transformation. Pure ceria is used in several organic reactions, such as the dehydration of alcohols, the alkylation of aromatic compounds, ketone formation, and aldolization, and in redox reactions. Ceria-supported metal catalysts allow the hydrogenation of many unsaturated compounds. They can also be used for coupling or ring-opening reactions. Cerium atoms can be added as dopants to catalytic system or impregnated onto zeolites and mesoporous catalyst materials to improve their performances. This Review demonstrates that the exceptional surface (and sometimes bulk) properties of ceria make cerium-based catalysts very effective for a broad range of organic reactions.

  13. Stability of IRA-45 solid amine resin as a function of carbon dioxide absorption and steam desorption cycling

    Wood, Peter C.; Wydeven, Theodore


    The removal of CO2 from the NASA Space Station's cabin atmosphere, which may be undertaken by a solid-amine water (steam)-desorbed system, is presently evaluated with a view to long-term amine resin stability and adsorption/desorption cycling by means of an automated laboratory flow-testing facility. While the CO2-adsorption capacity of the IRA-45 amine resin used gradually decreased over time, the rate of degradation significantly decreased after the first 10 cycles. Attention is given to the presence (and possible need for removal) of trimethylamine in the process air downstream of the resin bed.

  14. Optimizing the Synthesis of Ethyl tert-Butyl Ether in Continuous Catalytic Distillation Column Using New Ion Exchange Resin Catalyst

    Muhammad Umar; Yahia Abubakar Al-Hamed; Abdulraheem Al-Zahrani; Hisham Saeed Bamufleh


    Liquid phase synthesis of one of the important fuel oxygenate, ethyl tert-butyl ether (ETBE), from etha-nol and tert-butyl alcohol (TBA) has been studied in catalytic distillation column (CDC) using ion exchange resin catalyst CT-145H. A packed CDC of 1.2 m height and 50 mm diameter with indigenously developed reactive sec-tion packing was used to generate experimental data. Effect of different key variables on product purity in distillate, was investigated to find the optimum operating conditions for ETBE synthesis. The optimum conditions for 0.2 kg·s-1 of ethanol feed were found:reboiler duty of 375 W, molar feed ratio of 1︰1.3 of reactants, and reflux ratio of 7. Concentration profiles for each component along each column section at optimum conditions were also drawn. Neither output nor input multiplicity was observed at experimental conditions.

  15. Experiments on decolourization with 122-resin for extraction of gibberellins from solid medium under different conditions

    WUHong-sheng; FANJia-qing; SHIGuang-hui; ZHAONan-hai


    The extracting liquid of gibberellins (Gibberella fujikurol) from solid medium for was decolorized separately with 75%,95% alcohol, and distilled water in static adsorption and vibrating way for different durations. The results showed that the content of GA3 in efflux extracted with alcohol is 10% higher than that with distilled water. With the increase of the durations of extraction,the content of GA3 increases and the dissolution of pigments also increase. For extraction of GA3 cultured in solid medium, the best decolorizing result was obtained when it was extracted with 75%-95% alcohol in static way for 1-3 h, or in a vibrating way for 30-60 min, and then to decolor in a static way for 30-60 min in 122 resin column.

  16. Improved resins and novel materials and methods for solid phase extraction and high performance liquid chromatography

    Freeze, Ronald [Iowa State Univ., Ames, IA (United States)


    Solid-phase extraction (SPE) has grown to be one of the most widely used methods for isolation and preconcentration of a vast range of compounds from aqueous solutions. By modifying polymeric SPE resins with chelating functional groups, the selective uptake of metals was accomplished. The resin, along with adsorbed metals, was vaporized in the ICP and detection of the metals was then possible using either mass or emission spectroscopy. Drug analyses in biological fluids have received heightened attention as drug testing is on the increase both in sports and in the work environment. By using a direct-injection technique, biological fluids can be injected directly into the liquid chromatographic system with no pretreatment. A new surfactant, a sulfonated form of Brij-30 (Brij-S) is shown to prevent the uptake of serum proteins on commercial HPLC columns by forming a thin coating on the silica C18 surface. Excellent separations of eight or more drugs with a wide range of retention times were obtained. The separations had sharper peaks and lower retention times than similar separations performed with the surfactant sodium dodecylsulfate (SDS). Quantitative recovery of a number of drugs with limits of detection near 1 ppm with a 5 μl injection volume were obtained. Finally, a method for solid-phase extraction in a syringe is introduced. The system greatly reduced the volume of solvent required to elute adsorbed analytes from the SPE bed while providing a semi-automated setup. SPE in a syringe consists of a very small bed of resin-loaded membrane packed into a GC or HPLC syringe. After extraction, elution was performed with just a few μl of solvent. This small elution volume allowed injection of the eluent directly from the syringe into the chromatographic system, eliminating the handling problems associated with such small volumes.

  17. Dry entrapment of enzymes by epoxy or polyester resins hardened on different solid supports.

    Barig, Susann; Funke, Andreas; Merseburg, Andrea; Schnitzlein, Klaus; Stahmann, K-Peter


    Embedding of enzymes was performed with epoxy or polyester resin by mixing in a dried enzyme preparation before polymerization was started. This fast and low-cost immobilization method produced enzymatically active layers on different solid supports. As model enzymes the well-characterized Thermomyces lanuginosus lipase and a new threonine aldolase from Ashbya gossypii were used. It was shown that T. lanuginosus lipase recombinantly expressed in Aspergillus oryzae is a monomeric enzyme with a molecular mass of 34kDa, while A. gossypii threonine aldolase expressed in Escherichia coli is a pyridoxal-5'-phosphate binding homotetramer with a mass of 180kDa. The enzymes were used freeze dried, in four different preparations: freely diffusing, adsorbed on octyl sepharose, as well as cross-linked enzyme aggregates or as suspensions in organic solvent. They were mixed with standard two-component resins and prepared as layers on solid supports made of different materials e.g. metal, glass, polyester. Polymerization led to encapsulated enzyme preparations showing activities comparable to literature values.

  18. Novel polymeric resin for solid phase extraction and determination of lead in waters

    Karaaslan, Nagihan M.; Cengiz, Emine; Yaman, Mehmet [Science Faculty, Department of Chemistry, Firat University, Elazig (Turkey); Senkal, B. Filiz [Science and Arts Faculty, Department of Chemistry, Istanbul Technical University, Istanbul (Turkey)


    Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry and the high costs of other sensitive methods in compared to flame atomic absorption spectrometry (FAAS). Among preconcentration techniques, solid-phase extraction is the most popular because of a number of advantages. In this work, thiol-containing sulfonamide resin was synthesized, characterized, and applied as a new sorption material for solid phase extraction and determination of lead in natural water samples. The optimization of experimental conditions was performed using the parameters including pH, contact time, and volumes of initial and elution solutions. After preconcentration procedure, FAAS was used for determinations. The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent as well as high sorption capacity. Consequently, 280-fold improvement in the sensitivity of analytical scheme was achieved by combining the slotted tube atom trap-atomic absorption spectrometry (STAT-FAAS) and the developed preconcentration method. The limit of detection was found to be 0.15 ng mL{sup -1}. The Pb{sup 2+} concentrations in the studied water samples were found to be in the range of 0.9-6.7 ng mL{sup -1}. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. Characterization and Design of Zeolite Catalysts Solid Acidity, Shape Selectivity and Loading Properties

    Niwa, Miki; Okumura, Kazu


    Zeolites are microporous, aluminosilicate minerals commonly used as commercial adsorbents. Zeolite-based catalysts are used by industrial chemical companies in the interconversion of hydrocarbons and the alkylation of aromatic compounds. The current book deals with the characterization of specific properties of Zeolites and calculations for the design of catalysts. Measurements and utilization of solid acidity, shape selectivity, and loading properties, that are three prominent properties of a Zeolite catalyst, are treated in detail. These features concern chemical vapor deposition of silica, shape selectivity, loading properties, solid activity, Brønsted or Lewis character, ammonia temperature programmed desorption, control of the pore-opening size by chemical vapor deposition of silica and XAFS analysis of metals being highly dispersed inside and outside a framework.

  20. Solid Catalyst with Ionic Liquid Layer (SCILL). A concept to improve the selectivity of selective hydrogenations

    Jess, A.; Korth, W. [Bayreuth Univ. (Germany). Chair of Chemical Engineering


    Catalytic hydrogenations are important for refinery processes, petrochemical applications as well as for numerous processes of the fine chemicals industry. In some cases, hydrogenations consist of a sequence of consecutive reactions, and the desired product is the intermediate. An important goal is then a high yield and selectivity to the intermediate, if possible at a high conversion degree. The selectivity to an intermediate primarily depends on the chemical nature of the catalyst, but may also be influenced by diffusion processes. Ionic liquids (ILs) are low melting salts (< 100 C) and represent a promising solvent class. This paper focuses on the concept of a Solid Catalyst with Ionic Liquid Layer (SCILL), where the solid catalyst is coated with a thin IL layer to improve the selectivity. (orig.)

  1. A study on production of biodiesel using a novel solid oxide catalyst derived from waste.

    Majhi, Samrat; Ray, Srimanta


    The issues of energy security, dwindling supply and inflating price of fossil fuel have shifted the global focus towards fuel of renewable origin. Biodiesel, having renewable origin, has exhibited great potential as substitute for fossil fuels. The most common route of biodiesel production is through transesterification of vegetable oil in presence of homogeneous acid or base or solid oxide catalyst. But, the economics of biodiesel is not competitive with respect to fossil fuel due to high cost of production. The vegetable oil waste is a potential alternative for biodiesel production, particularly when disposal of used vegetable oil has been restricted in several countries. The present study evaluates the efficacy of a low-cost solid oxide catalyst derived from eggshell (a food waste) in transesterification of vegetable oil and simulated waste vegetable oil (SWVO). The impact of thermal treatment of vegetable oil (to simulate frying operation) on transesterification using eggshell-derived solid oxide catalyst (ESSO catalyst) was also evaluated along with the effect of varying reaction parameters. The study reported that around 90 % biodiesel yield was obtained with vegetable oil at methanol/oil molar ratio of 18:1 in 3 h reaction time using 10 % ESSO catalyst. The biodiesel produced with ESSO catalyst from SWVO, thermally treated at 150 °C for 24 h, was found to conform with the biodiesel standard, but the yield was 5 % lower compared to that of the untreated oil. The utilization of waste vegetable oil along with waste eggshell as catalyst is significant for improving the overall economics of the biodiesel in the current market. The utilization of waste for societal benefit with the essence of sustainable development is the novelty of this work.


    The reaction of neat 5- or 8-oxobenzopyran-2(1H)-ones with a variety of aromatic and heteroaromatic hydrazines are remarkably accelerated upon irradiation in a household microwave oven in the absence of any catalyst, solid support or solvent. The approach provides an attractive a...

  3. Highly Selective Liquid-Phase Benzylation of Anisole with Solid-Acid Zeolite Catalysts

    Poreddy, Raju; Shunmugavel, Saravanamurugan; Riisager, Anders


    Zeolites were evaluated as solid acid catalysts for the liquid-phase benzylation of anisole with benzyl alcohol, benzyl bromide, and benzyl chloride at 80 °C. Among the examined zeolites, H-mordenite-10 (H-MOR-10) demonstrated particular high activity (>99 %) and excellent selectivity (>96...

  4. Alkene Isomerization Using a Solid Acid as Activator and Support for a Homogeneous Catalyst

    Seen, Andrew J.


    An upper-level undergraduate experiment that, in addition to introducing students to catalysis using an air sensitive transition-metal complex, introduces the use of a solid acid as an activator and support for the catalyst is developed. The increased stability acquired in the course of the process affords the opportunity to characterize the…

  5. Catalytic Upgrading of bio-oil using 1-octene and 1-butanol over sulfonic acid resin catalysts

    Zhang, Zhijun; Wang, Qingwen; Tripathi, Prabhat; Pittman, Charles U.


    Raw bio-oil from fast pyrolysis of biomass must be refined before it can be used as a transporation fuel, a petroleum refinery feed or for many other fuel uses. Raw bio-oil was upgraded with the neat model olefin, 1-octene, and with 1-octene/1-butanol mixtures over sulfonic acid resin catalysts frin 80 to 150 degrees celisus in order to simultaneously lower water content and acidity and to increase hydrophobicity and heating value. Phase separation and coke formation were key factors limiting the reaction rate during upgrading with neat 1-octene although octanols were formed by 1-octene hydration along with small amounts of octyl acetates and ethers. GC-MS analysis confirmed that olefin hydration, carboxylic acid esterification, acetal formation from aldehydes and ketones and O- and C-alkylations of phenolic compounds occurred simultaneously during upgrading with 1-octene/1-butanol mixtures. Addition of 1-butanol increased olefin conversion dramatically be reducing mass transfer restraints and serving as a cosolvent or emulsifying agent. It also reacted with carboxylic acids and aldehydes/ketones to form esters, and acetals, respectively, while also serving to stabilize bio-oil during heating. 1-Butanol addition also protected the catalysts, increasing catalyst lifetime and reducing or eliminationg coking. Upgrading sharply increased ester content and decreased the amounts of levoglucosan, polyhydric alcohols and organic acids. Upgrading lowered acidity (pH value rise from 2.5 to >3.0), removed the uppleasant ordor and increased hydrocarbon solubility. Water content decreased from 37.2% to < 7.5% dramatically and calorific value increased from 12.6 MJ kg to about 30.0 MJ kg.

  6. Ionic-liquid-impregnated resin for the microwave-assisted solid-liquid extraction of triazine herbicides in honey.

    Wu, Lijie; Song, Ying; Hu, Mingzhu; Yu, Cui; Zhang, Hanqi; Yu, Aimin; Ma, Qiang; Wang, Ziming


    Microwave-assisted ionic-liquid-impregnated resin solid-liquid extraction was developed for the extraction of triazine herbicides, including cyanazine, metribuzin, desmetryn, secbumeton, terbumeton, terbuthylazine, dimethametryn, and dipropetryn in honey samples. The ionic-liquid-impregnated resin was prepared by immobilizing 1-hexyl-3-methylimidazolium hexafluorophosphate in the microspores of resin. The resin was used as the extraction adsorbent. The extraction and enrichment of analytes were performed in a single step. The extraction time can be shortened greatly with the help of microwave. The effects of experimental parameters including type of resin, type of ionic liquid, mass ratio of resin to ionic liquid, extraction time, amount of the impregnated resin, extraction temperature, salt concentration, and desorption conditions on the extraction efficiency, were investigated. A Box-Behnken design was applied to the selection of the experimental parameters. The recoveries were in the range of 80.1 to 103.4% and the relative standard deviations were lower than 6.8%. The present method was applied to the analysis of honey samples.

  7. Synthesis of Resins with Chiral Salen Complexes

    WANG; YunPu


    The enormous growth in the use of polymer resin supports in solid phase combinatorial synthesis, and related methodologies, has re-stimulated interest in the area of polymer-supported transition metal complex catalyst .The recently developed chiral salen-based for the enantioselective ring opening of meso epoxides and kinetic resolution of terminal epoxides are appealing candidates for immobilization on solid support. The catalysts are reading prepare from inexpensive components, and are amenable to modification for attachment to a solid support.  ……

  8. Low-temperature, vapor-liquid-solid, laterally grown silicon films using alloyed catalysts

    LeBoeuf, Jerome L.; Brodusch, Nicolas; Gauvin, Raynald; Quitoriano, Nathaniel J.


    Using amorphous oxide templates known as micro-crucibles which confine a vapor-liquid-solid catalyst to a specific geometry, two-dimensional silicon thin-films of a single orientation have been grown laterally over an amorphous substrate and defects within crystals have been necked out. The vapor-liquid-solid catalysts consisted nominally of 99% gold with 1% titanium, chromium, or aluminum, and each alloy affected the processing of micro-crucibles and growth within them significantly. It was found that chromium additions inhibited the catalytic effect of the gold catalysts, titanium changed the morphology of the catalyst during processing and aluminum stabilized a potential third phase in the gold-silicon system upon cooling. Two mechanisms for growing undesired nanowires were identified both of which hindered the VLS film growth, fast silane cracking rates and poor gold etching, which left gold nanoparticles near the gold-vapor interface. To reduce the silane cracking rates, growth was done at a lower temperature while an engineered heat and deposition profile helped to reduce NWs caused by the second mechanism. Through experimenting with catalyst compositions, the fundamental mechanisms which produce concentration gradients across the gold-silicon alloy within a given micro-crucible have been proposed. Using the postulated mechanisms, micro-crucibles were designed which promote high-quality, single crystal growth of semiconductors.

  9. Transesterification of soybean oil catalyzed by potassium loaded on alumina as a solid-base catalyst

    Xie, Wenlei; Chen, Ligong [School of Pharmaceutical Technology and Science, Tianjin University, Tianjin 300072 (China); Peng, Hong [School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou 450052 (China)


    Biodiesel fuel, consisting of methyl esters of long chain fatty acids produced by transesterification of vegetable oils or animal fats with methanol, is a promising alternative diesel fuel regarding the limited resources of fossil fuels and the environmental concerns. In this work, an environmentally benign process for the transesterification of soybean oil to methyl esters using alumina loaded with potassium as a solid base catalyst in a heterogeneous manner was developed. The catalyst loaded KNO{sub 3} of 35wt.% on Al{sub 2}O{sub 3}, after being calcined at 773K for 5h, it was found to be the optimum catalyst, which can give the highest basicity and the best catalytic activity for this reaction. The effects of various reaction variables such as the catalyst loading, oil to methanol ratio, reaction time and temperature on the conversion of soybean oil were investigated. The catalysts were characterized by means of XRD, IR and Hammett titration method. The results indicated that K{sub 2}O derived from KNO{sub 3} at high temperature and that the Al-O-K groups were, probably, the main reasons for the catalytic activity towards the reaction. The catalyst activity was correlated closely with its basicity as determined by the Hammett method.

  10. A Microwave-Sensitive Solid Acid Catalyst Prepared from Sweet Potato via a Simple Method

    Hai-Ying Chen


    Full Text Available In this study, a microwave-sensitive solid acid catalyst was successfully synthesized from sweet potatoes via a simple process. The catalyst was proven to have superior microwave-sensitive and homogeneous properties. The physicochemical properties were characterized by Brunauer–Emmett–Teller (BET, X-ray diffraction (XRD, Fourier-transform infrared spectra (FT-IR, thermogravimetric (TGA, scanning electron microscope (SEM and elemental analysis (EA. Results showed that the total acid density and specific surface area for the catalyst were 6.35 mmol/g and 78.35 m2/g, respectively. The elemental sulfur content reached 7.449% after sulfonation and the catalytic activity could reach over 91% within 30 min with microwave power density of 1.0 W/mL. The catalytic reaction temperature should not exceed 200 °C, as shown in TGA curve, and the moisture content in the oil raw material should be within 1%–2%. The catalyst deactivated gradually to 64.38% after reutilization five times, but the catalytic activity could be simply regenerated by re-sulfonation, albeit slightly reduced (87.56%. The shift of diffraction peaks in the XRD patterns and new absorption peaks at 619.98 and 1190.49 cm−1 of FT-IR spectra demonstrated that the –SO3H group was effectively attached to the catalyst. The SEM images displayed a loose and porous amorphous structure in the end catalyst.

  11. Metal Chlorides Supported Solid Catalysts for F-C Acylations of Arenes

    李阳; 刘云龙; 穆曼曼; 陈立功


    A series of metal chlorides supported solid catalysts were prepared by simple wet impregnation method. Their catalytic performances for Friedel-Crafts acylation of toluene with benzoyl chloride were evaluated and the excellent results were obtained over FeCl3/SiO2. These catalysts were characterized by BET, NH3-TPD and FT-IR of pyridine adsorption to clarify the structure-activity relationship. It was found that FeCl3/SiO2 has larger pore size and pore volume than other catalysts, which increased the accessibility of the catalyst. In addition, FeCl3/SiO2 ex-hibited higher molar ratio of Lewis acid sites and Brφnsted acid sites, which might be another reason for the in-crease of toluene conversion. Furthermore, the reaction parameters, including temperature, time and molar ratio, were optimized. Under the optimized conditions, 91.2%, conversion and 82.0%, selectivity were obtained. Mean-while, the generality of the catalyst was demonstrated by the acylations of alkyl substituted aromatics. Finally, the catalyst was reused for four runs with slight loss in catalytic activity, which attributed to the drain of the active component.

  12. Self-Supporting Metal-Organic Layers as Single-Site Solid Catalysts

    Cao, Lingyun; Lin, Zekai; Peng, Fei; Wang, Weiwei; Huang, Ruiyun; Wang, Cheng; Yan, Jiawei; Liang, Jie; Zhang, Zhiming; Zhang, Teng; Long, Lasheng; Sun, Junliang; Lin, Wenbin (StockholmU); (UC); (Xiamen)


    Metal–organic layers (MOLs) represent an emerging class of tunable and functionalizable two-dimensional materials. In this work, the scalable solvothermal synthesis of self-supporting MOLs composed of [Hf6O4(OH)4(HCO2)6] secondary building units (SBUs) and benzene-1,3,5-tribenzoate (BTB) bridging ligands is reported. The MOL structures were directly imaged by TEM and AFM, and doped with 4'-(4-benzoate)-(2,2',2''-terpyridine)-5,5''-dicarboxylate (TPY) before being coordinated with iron centers to afford highly active and reusable single-site solid catalysts for the hydrosilylation of terminal olefins. MOL-based heterogeneous catalysts are free from the diffusional constraints placed on all known porous solid catalysts, including metal–organic frameworks. This work uncovers an entirely new strategy for designing single-site solid catalysts and opens the door to a new class of two-dimensional coordination materials with molecular functionalities.

  13. The application of Ce-Zr oxide solid solution to oxygen storage promoters in automotive catalysts

    Ozawa, Msakuni (Toyota Central Research and Development Labs. Inc., Aichi (Japan)); Kimura, Mareo (Toyota Central Research and Development Labs. Inc., Aichi (Japan)); Isogai, Akio (Toyota Central Research and Development Labs. Inc., Aichi (Japan))


    The complex oxides in the CeO[sub 2]-ZrO[sub 2] system were examined for the improvement of oxygen storage capacity in automotive catalysts. The formation of Ce-Zr oxide solid solution improved the thermal stability and activity of CeO[sub 2]. The Ce-Zr addition enhanced the removal activity for CO, NO[sub x] and hydrocarbons under dynamic air-fuel ratio condition. The automotive catalyst was designed and developed through research on the oxides in the CeO[sub 2]-ZrO[sub 2] system. (orig.)

  14. Catalytic esterification via silica immobilized p-phenylenediamine and dithiooxamide solid catalysts

    Thana Jaafar Al-Hasani


    Full Text Available The p-phenylenediamine (PDA and dithiooxamide (DTO were immobilized onto silica from rice husk ash (RHA using 3-chloropropyltriethoxyilane (CPTES to form a solid catalyst denoted as RHAPDA and RHADTO, respectively. BET measurements of the catalysts showed the surface area to be 145 and 9.7 m2 g−1 with an average pore diameter of 9.8 and 10.9 nm, respectively. The catalytic performance of RHAPDA and RHADTO was tested in the esterification of ethyl alcohol with acetic acid. A conversion of 48% and 69% was achieved, respectively with 100% selectivity toward ethyl acetate.

  15. Meso- and macroporous sulfonated starch solid acid catalyst for esterification of palm fatty acid

    Ibrahim M. Lokman


    Full Text Available In the present work, a heterogeneous solid acid catalyst was successfully developed from starch. The catalyst was prepared by a significant two-step process; the initial step was incomplete carbonization of starch (ICS at 400 °C for 12 h and consequently followed by sulfonation process using concentrated H2SO4 to produce sulfonated-incomplete carbonized starch (ICS-SO3H. The characterization of the ICS-SO3H catalyst was done for chemical and physical properties such as X-ray diffraction (XRD, ammonia-temperature programmed desorption (NH3-TPD, surface area analysis, thermal gravimetric analysis (TGA, elemental analysis and morphology analysis by scanning electron microscope (SEM. BET results showed the structure of ICS-SO3H consists of meso- and macro-porous properties, which allowed high density of the SO3H group attached on its carbon networks. The catalytic activity of ICS-SO3H catalyst was determined by analyzing the catalyst performance to esterify palm fatty acid distillate (PFAD and sequentially produced methyl ester. The maximum free fatty acid (FFA conversion and FAME yield were as high as 94.6% and 90.4%, respectively, at 75 °C using 10:1 methanol-to-PFAD molar ratio and 2 wt.% of catalyst within 3 h. The catalyst has sufficient potential to recycle up to 6 reactions without reactivation step and any remarkable loss of catalytic activity. It revealed that the heterogeneous ICS-SO3H catalyst exhibits high stability, reusability and catalytic activity.

  16. Biodiesel production from non-edible Silybum marianum oil using heterogeneous solid base catalyst under ultrasonication.

    Takase, Mohammed; Chen, Yao; Liu, Hongyang; Zhao, Ting; Yang, Liuqing; Wu, Xiangyang


    The aim of this study is to investigate modified TiO2 doped with C4H4O6HK as heterogeneous solid base catalyst for transesterification of non-edible, Silybum marianum oil to biodiesel using methanol under ultrasonication. Upon screening the catalytic performance of modified TiO2 doped with different K-compounds, 0.7 C4H4O6HK doped on TiO2 was selected. The preparation of the catalyst was done using incipient wetness impregnation method. Having doped modified TiO2 with C4H4O6HK, followed by impregnation, drying and calcination at 600 °C for 6 h, the catalyst was characterized by XRD, FTIR, SEM, BET, TGA, UV and the Hammett indicators. The yield of the biodiesel was proportional to the catalyst basicity. The catalyst had granular and porous structures with high basicity and superior performance. Combined conditions of 16:1 molar ratio of methanol to oil, 5 wt.% catalyst amount, 60 °C reaction temperature and 30 min reaction time was enough for maximum yield of 90.1%. The catalyst maintained sustained activity after five cycles of use. The oxidative stability which was the main problem of the biodiesel was improved from 2.0 h to 3.2h after 30 days using ascorbic acid as antioxidant. The other properties including the flash point, cetane number and the cold flow ones were however, comparable to international standards. The study indicated that Ti-0.7-600-6 is an efficient, economical and environmentally, friendly catalyst under ultrasonication for producing biodiesel from S. marianum oil with a substantial yield.

  17. Synthesis of a nano-crystalline solid acid catalyst from fly ash and its catalytic performance

    Chitralekha Khatri; Ashu Rani [Government P.G. College, Kota (India). Environmental Chemistry Laboratory


    The synthesis of nano-crystalline activated fly ash catalyst (AFAC) with crystallite size of 12 nm was carried out by chemical and thermal treatment of fly ash, a waste material generated from coal-burning power plants. Fly ash was chemically activated using sulfuric acid followed by thermal activation at 600{sup o}C. The variation of surface and physico-chemical properties of the fly ash by activation methods resulted in improved acidity and therefore, catalytic activity for acid catalyzed reactions. The AFAC was characterized by X-ray diffraction, FT-IR spectroscopy, N{sub 2}-adsorption-desorption isotherm, scanning electron microscopy, flame atomic absorption spectrophotometry and sulfur content by CHNS/O elemental analysis. It showed amorphous nature due to high silica content (81%) and possessed high BET surface area (120 m{sup 2}/g). The catalyst was found to be highly active solid acid catalyst for liquid phase esterification of salicylic acid with acetic anhydride and methanol giving acetylsalicylic acid and methyl salicylate respectively. A maximum yield of 97% with high purity of acetylsalicylic acid (aspirin) and a very high conversion 87% of salicylic acid to methyl salicylate (oil of wintergreen) was obtained with AFAC. The surface acidity and therefore, catalytic activity in AFAC was originated by increased silica content, hydroxyl content and higher surface area as compared to fly ash. The study shows that coal generated fly ash can be converted into potential solid acid catalyst for acid catalyzed reactions. Furthermore, this catalyst may replace conventional environmentally hazardous homogeneous liquid acids making an ecofriendly; solvent free, atom efficient, solid acid based catalytic process. 27 refs., 5 figs., 2 tabs.

  18. Solid state NMR investigation of silica aerogel supported Fischer-Tropsch catalysts

    Ma, Zhiru; Dunn, Brian C.; Turpin, Gregory C.; Eyring, Edward M.; Ernst, Richard D.; Pugmire, Ronald J. [Department of Chemistry, University of Utah, Salt Lake City, UT 84112 (United States)


    The Fischer-Tropsch (F-T) catalyst is the critical component for the F-T synthesis of a variety of hydrocarbons from syngas. Fischer-Tropsch cobalt, iron and ruthenium catalysts supported on silica aerogel have been prepared using a combination of sol-gel chemistry and vapor phase deposition methods. Solid state NMR spectroscopy, a very powerful technique for analyzing the structure and dynamics of various materials, was employed in the study of these F-T catalyst systems. The silica aerogel supported F-T catalysts have been investigated using both solid state {sup 29}Si and {sup 13}C NMR methods. The silica aerogel's tetrahedral sub-unit structure and the influence of the loaded metal compounds have been observed. Three types of Si(O{sub 1/2}){sub 4} tetrahedral unit structure (Q{sub 2}, Q{sub 3} and Q{sub 4}) are clearly resolved in the silica aerogel samples. The calcining process and the loading of metal compounds produce line broadening in the {sup 29}Si spectra sufficient to prevent clear resolution of the three distinct Q{sub n} spectral lines, but the broadened spectra indicate that the three Q sub-unit structures are still present. The ferrocene and ruthenocene molecules used in the vapor phase deposition method exhibit a rapid exchange within the silica aerogel support similar to what one would expect in the gas or liquid state. (author)


    Zuogang Guo


    Full Text Available Molecular distillation technology has been adopted to obtain a bio-oil fraction rich in carboxylic acids and ketones. This unique bio-oil fraction was then upgraded with a La-promoted solid acid catalyst. Three washing pretreatments were used to prepare catalysts A, B, and C, with the intention of reducing the amounts of residual sulfuric acid. Model reactions were used to estimate their catalytic activities and the residual amounts of sulfuric acid. Catalyst B, with washing after calcination, displayed higher catalytic activity (80.83% and lower residual amount of sulfuric acid (50 μmol/g. The catalysts were characterized by techniques such as BET, XRD, and SEM to explain the differences in their catalytic activities. The optimum catalyst B was used in the upgrading of the bio-oil molecular distillation fraction. After upgrading, the corrosivity of the bio-oil fraction declined and its storage stability was improved. The carboxylic acid content in the upgraded bio-oil fraction decreased from 18.39% to 2.70%, while the ester content increased from 0.72% to 31.17%. The conversion of corrosive carboxylic acids to neutral esters reduced the corrosivity of the bio-oil fraction. Moreover, the ketones with unsaturated carbon-carbon double bonds (such as 2-cyclopenten-1-one, 3-methyl-2-cyclopenten-1-one, etc. were converted into saturated compounds, which improved the stability of the bio-oil fraction.

  20. Ultrasound assisted transesterification of waste cooking oil using heterogeneous solid catalyst.

    Pukale, Dipak D; Maddikeri, Ganesh L; Gogate, Parag R; Pandit, Aniruddha B; Pratap, Amit P


    Transesterification based biodiesel production from waste cooking oil in the presence of heterogeneous solid catalyst has been investigated in the present work. The effect of different operating parameters such as type of catalyst, catalyst concentration, oil to methanol molar ratio and the reaction temperature on the progress of the reaction was studied. Some studies related to catalyst reusability have also been performed. The important physicochemical properties of the synthesized biodiesel have also been investigated. The results showed that tri-potassium phosphate exhibits high catalytic activity for the transesterification of waste cooking oil. Under the optimal conditions, viz. catalyst concentration of 3wt% K3PO4, oil to methanol molar ratio of 1:6 and temperature of 50°C, 92.0% of biodiesel yield was obtained in 90min of reaction time. Higher yield was obtained in the presence of ultrasound as compared to conventional approach under otherwise similar conditions, which can be attributed to the cavitational effects. Kinetic studies have been carried out to determine the rate constant at different operating temperatures. It was observed that the kinetic rate constant increased with an increase in the temperature and the activation energy was found to be 64.241kJ/mol. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Removal of Cl adsorbed on Mn-Ce-La solid solution catalysts during CVOC combustion.

    Wang, Xingyi; Ran, Le; Dai, Yu; Lu, Yuanjiao; Dai, Qiguang


    Mn-Ce-La oxide-mixed catalysts prepared by the method of complexation followed by calcination at 750°C were tested in the catalytic combustion of chlorobenzene (CB) taken as a model of chlorinated aromatics. XRD analyses show that Mn and La enter CeO2 matrix with a fluorite-like structure to form solid solution. The catalysts with high ratio of Mn/Mn+Ce+La exhibit high activity for CB combustion, due to high oxygen mobility. For all Mn-Ce-La catalysts, deactivation due to Cl adsorption is observed at different temperatures, depending on composition. At 330°C or higher temperature, the removal of Cl species from the surface in the forms of Cl2 (produced through Deacon reaction) and HCl (produced through hydrolysis of Cl) occurs and the activity of catalysts for CB combustion becomes thus stable. Either the addition of water or the increase in gaseous oxygen concentration can promote the removal of Cl species, and thus to increase the activity for CB combustion. High stable activity of Mn-Ce-La catalysts can be related to the combination of good oxidation and Deacon reaction performances.

  2. Resin-Immobilized Palladium Nanoparticle Catalysts for Organic Reactions in Aqueous Media: Morphological Aspects

    Piero Mastrorilli


    Full Text Available An insight into the nano- and micro-structural morphology of a polymer supported Pd catalyst employed in different catalytic reactions under green conditions is reported. The pre-catalyst was obtained by copolymerization of the metal-containing monomer Pd(AAEMA2 [AAEMA− = deprotonated form of 2-(acetoacetoxy ethyl methacrylate] with ethyl methacrylate as co-monomer, and ethylene glycol dimethacrylate as cross-linker. This material was used in water for the Suzuki-Miyaura cross-coupling of aryl bromides, and for the reduction of nitroarenes and quinolines using NaBH4 or H2, as reductants. TEM analyses showed that in all cases the pristine Pd(II species were reduced in situ to Pd(0, which formed metal nanoparticles (NPs, the real active species. The dependence of their average size (2–10 nm and morphology on different parameters (temperature, reducing agent, presence of a phase transfer agent is discussed. TEM and micro-IR analyses showed that the polymeric support retained its porosity and stability for several catalytic cycles in all reactions and Pd NPs did not aggregate after reuse. The metal nanoparticle distribution throughout the polymer matrix after several recycles provided precious information about the catalytic mechanism, which was truly heterogeneous in the hydrogenation reactions and of the so-called “release and catch” type in the Suzuki coupling.

  3. Solid-phase staudinger ligation from a novel core-shell-type resin: a tool for facile condensation of small peptide fragments.

    Kim, Hanyoung; Cho, Jin Ku; Aimoto, Saburo; Lee, Yoon-Sik


    [reaction: see text] Solid-phase Staudinger ligation of small peptides was performed on a novel core-shell-type resin. Solid-phase Staudinger ligation was mediated by synthetic solid-supported phosphinothiol, which was readily prepared by a straightforward synthetic route. This protocol afforded final peptide products in excellent yields and purities and thus could provide the opportunity to facilitate a simple manipulation for condensation of peptide fragments. In particular, the resulting resin could be recycled in a successful manner.

  4. Superparamagnetic mesoporous Mg-Fe bi-metal oxides as efficient magnetic solid-base catalysts for Knoevenagel condensations.

    Gao, Zhe; Zhou, Jian; Cui, Fangming; Zhu, Yan; Hua, Zile; Shi, Jianlin


    Superparamagnetic mesoporous Mg-Fe bi-metal oxides with varied Mg-Fe atomic ratios have been successfully synthesized as solid base catalysts. The M2F-400 catalyst with Mg/Fe atomic ratio = 2 showed extraordinarily high activities for Knoevenagel reactions even at room temperature. It could be magnetically separated, recycled, and reused for at least five cycles.

  5. Application of solid-acid catalyst and marine macro-algae Gracilaria verrucosa to production of fermentable sugars.

    Jeong, Gwi-Taek; Kim, Sung-Koo; Park, Don-Hee


    In this study, the hydrolysis of marine macro-algae Gracilaria verrucosa with a solid-acid catalyst was investigated. To optimize the hydrolysis, four reaction factors, including liquid-to-solid ratio, catalyst loading, reaction temperature, and reaction time, were investigated. In the results, the highest total reducing sugar (TRS) yield, 61 g/L (51.9%), was obtained under the following conditions: 1:7.5 solid-to-liquid ratio, 15% (w/v) catalyst loading, 140 °C reaction temperature, and 150 min reaction time. Under these conditions, 10.7 g/L of 5-HMF and 2.5 g/L of levulinic acid (LA) were generated. The application of solid-acid catalyst and marine macro-algae resources shows a very high potential for production of fermentable sugars. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Synthesis, solid-state NMR characterization, and application for hydrogenation reactions of a novel Wilkinson's-type immobilized catalyst.

    Abdulhussain, Safaa; Breitzke, Hergen; Ratajczyk, Tomasz; Grünberg, Anna; Srour, Mohamad; Arnaut, Danjela; Weidler, Heiko; Kunz, Ulrike; Kleebe, Hans Joachim; Bommerich, Ute; Bernarding, Johannes; Gutmann, Torsten; Buntkowsky, Gerd


    Silica nanoparticles (SiNPs) were chosen as a solid support material for the immobilization of a new Wilkinson's-type catalyst. In a first step, polymer molecules (poly(triphenylphosphine)ethylene (PTPPE); 4-diphenylphosphine styrene as monomer) were grafted onto the silica nanoparticles by surface-initiated photoinferter-mediated polymerization (SI-PIMP). The catalyst was then created by binding rhodium (Rh) to the polymer side chains, with RhCl3⋅x H2O as a precursor. The triphenylphosphine units and rhodium as Rh(I) provide an environment to form Wilkinson's catalyst-like structures. Employing multinuclear ((31)P, (29)Si, and (13)C) solid-state NMR spectroscopy (SSNMR), the structure of the catalyst bound to the polymer and the intermediates of the grafting reaction have been characterized. Finally, first applications of this catalyst in hydrogenation reactions employing para-enriched hydrogen gas (PHIP experiments) and an assessment of its leaching properties are presented.

  7. Biguanide-functionalized mesoporous SBA-15 silica as an efficient solid catalyst for interesterification of vegetable oils.

    Xie, Wenlei; Hu, Libing


    The biguanide-functionalized SBA-15 materials were fabricated by grafting of organic biguanide onto the SBA-15 silica through covalent attachments, and then this organic-inorganic hybrid material was employed as solid catalysts for the interesterification of triacylglycerols for the modification of vegetable oils. The prepared catalyst was characterized by FTIR, XRD, SEM, TEM, nitrogen adsorption-desorption and elemental analysis. The biguanide base was successfully tethered onto the SBA-15 silica with no damage to the ordered mesoporous structure of the silica after the organo-functionalization. The solid catalyst had stronger base strength and could catalyze the interesterification of triacylglycerols. The fatty acid compositions and triacylglycerol profiles of the interesterified products were noticeably varied following the interesterification. The reaction parameters, namely substrate ratio, reaction temperature, catalyst loading and reaction time, were investigated for the interesterification of soybean oil with methyl decanoate. The catalyst could be reused for at least four cycles without significant loss of activity.

  8. Solid phase extractive preconcentration of uranium(VI) using quinoline-8-ol anchored chloromethylated polymeric resin beads.

    Praveen, R S; Metilda, P; Daniel, S; Rao, T Prasada


    A new chelating polymeric sorbent has been developed using Merrifield chloromethylated resin anchored with quinoline-8-ol (HQ). The modified polymeric resin was characterized by FT-IR spectroscopy and elemental analysis. The HQ anchored resin showed superior binding affinity for U(VI) over Th(IV) and La(III). The influence of various physicochemical parameters on the recovery of U(VI) were optimized by both static and dynamic methods. The phase exchange kinetic studies performed for U(VI) revealed that XAD-16. The developed HQ anchored polymeric resin is highly selective as none of the extraneous species were found to have any deleterious effect. Solid phase extraction (SPE) studies performed using HQ anchored polymeric resin offered enrichment factor of 100 and the lowest concentration below which recoveries become non-quantitative is 5mugl(-1). The accuracy of the developed SPE method in conjunction with Arsenazo III procedure was tested by analyzing marine sediment (MESS-3) and soil (IAEA-Soil 7) reference materials. Furthermore, the above procedure has been successfully employed for the analysis of real soil and sediment samples.

  9. Preparation and application of zirconium sulfate supported on SAPO-34 molecular sieve as solid acid catalyst for esterification

    Xu, Dongyan, E-mail:; Ma, Hong; Cheng, Fei


    Graphical abstract: - Highlights: • SAPO-34 supported zirconium sulfate solid acid catalyst was prepared. • Esterification of acetic acid with ethanol can be catalyzed by ZS/SAPO-34. • The hydration of ZS is vital to the acidic property and catalytic performance. • The ZS/SAPO-34 catalyst treated at 200 °C shows good reusability. - Abstract: Zirconium sulfate (ZS) was supported on SAPO-34 molecular sieve by using an incipient wetness impregnation method with zirconium sulfate as the precursor. The as-prepared catalysts were used as solid acid catalyst for esterification reaction of acetic acid with ethanol. The influence of calcination temperature on the acidic property, catalytic activity, and reusability of ZS/SAPO-34 catalysts were mainly investigated. FT-IR, SEM, EDS and TG analysis have been carried out to demonstrate the characteristics of ZS/SAPO-34 catalysts. It was found that the 30 wt%ZS/SAPO-34 catalysts display the property of superacid irrespective of calcination temperature. The ZS/SAPO-34 catalyst treated at 200 °C can enhance the interaction between the supported ZS and SAPO-34 and keep the catalyst remaining substantially active after several reaction cycles. However, further increasing calcination temperature will cause the transfer of ZS from hydrate to anhydrous phase, and thus the decrease of activity.

  10. CO oxidation on Ta-Modified SnO2 solid solution catalysts

    Han, Xue; Xu, Xianglan; Liu, Wenming; Wang, Xiang; Zhang, Rongbin


    Co-precipitation method was adopted to prepare Sn-Ta mixed oxide catalysts with different Sn/Ta molar ratios and used for CO oxidation. The catalysts were investigated by N2-Brunauer-Emmett-Teller (N2-BET), X-ray diffraction patterns (XRD), H2-temperature programmed reduction (H2-TPR), Thermal Gravity Analysis - Differential Scanning Calorimetry (TGA-DSC) techniques. It is revealed that a small amount of Ta cations can be doped into SnO2 lattice to form solid solution by co-precipitation method, which resulted in samples having higher surface areas, improved thermal stability and more deficient oxygen species on the surface of SnO2. As a result, those Sn rich Sn-Ta solid solution catalysts with an Sn/Ta molar ratio higher than 4/2 showed significantly enhanced activity as well as good resistance to water deactivation. It is noted here that if tantala disperses onto SnO2 surface instead of doping into its lattice, it will then have negative effect on its activity.

  11. Catalytic conversion of xylose and corn stalk into furfural over carbon solid acid catalyst in γ-valerolactone.

    Zhang, Tingwei; Li, Wenzhi; Xu, Zhiping; Liu, Qiyu; Ma, Qiaozhi; Jameel, Hasan; Chang, Hou-min; Ma, Longlong


    A novel carbon solid acid catalyst was synthesized by the sulfonation of carbonaceous material which was prepared by carbonization of sucrose using 4-BDS as a sulfonating agent. TEM, N2 adsorption-desorption, elemental analysis, XPS and FT-IR were used to characterize the catalyst. Then, the catalyst was applied for the conversion of xylose and corn stalk into furfural in GVL. The influence of the reaction time, temperature and dosage of catalyst on xylose dehydration were also investigated. The Brønsted acid catalyst exhibited high activity in the dehydration of xylose, with a high furfural yield of 78.5% at 170°C in 30min. What's more, a 60.6% furfural yield from corn stalk was achieved in 100min at 200°C. The recyclability of the sulfonated carbon catalyst was perfect, and it could be reused for 5times without the loss of furfural yields.

  12. Development of Green Resin Using Solid Waste Protein Soybean Curd “Tofu” Production



    Full Text Available One of the most concerns associated with many commercially available composites is that they used of non-degradable resins and fibers that primarily made using non-degradable, petroleum-based chemicals as feed stock. These conditions will create a serious problem in term of waste disposal after end of their life. Unlike petroleum, plant based protein and starches are yearly renewable. These resins are increasingly developed for various applications as replacements for non-degradable petroleum based resins. In addition, these resins may be easily composted after their life. In this study, Soybean Pulp Hemi-cellulose (SPH was modified by cross-linking it with glutaraldehyde (GA. The modified SPH resins were characterized for its surface morphology, tensile and mass losses or biodegradability properties. The effect of GA on the surface morphology, tensile and biodegradability of the SPH resins were discussed. The SPH resins showed improved surface morphology and ductility. However, the increasing the GA content reduces the Young’s modulus of the SPH resins. The SPH resins exhibited fracture stress point and Young’s modulus maximum of and 3.02 MN/m2, respectively, and biodegradability of 40.42% after 30 days placed on the open air. These properties seem to be sufficient for developing green composites from the SPH resins reinforced with natural fiber for indoor structural applications

  13. Spent solid catalysts of chemical industry and petroleum refining; Les catalyseurs solides uses de l`industrie chimique et du raffinage petrolier

    Paillier, A.; Briand, Y.


    The aim of this work is the analysis of the heterogeneous catalysis. In a first part are given the utilizing sectors. There are mainly the petroleum refining, the chemical industry and the environment. A catalyst is chosen according to its selectivity and velocity, its cost and the wastes it induces. Thus are found three main heterogeneous catalysts series: the bulky metals, the supported metals: precious or heavy or their compounds, the zeolites and other silico-aluminates. Their most frequent uses are given. The catalysts used in the main petroleum refining processes (distillation, catalytic hydro-treatment, desulfurization, catalytic reforming, catalytic cracking, catalytic hydrocracking, alkylation) are also detailed. The second part deals with the spent solid catalysts. The reasons of the deactivation (poisons or contaminants, structure modification) are given. The spent catalysts are either regenerated or eliminated. The regeneration methods are described. The solid catalysts cannot be stored without being stabilized (decrease of its water permeability and of its leachable fraction). The stabilization methods are reviewed. The regulations on the spent solid catalysts are given in the last part. (O.M.)

  14. Cs salt of tungstophosphoric acid-promoted zirconium titanium phosphate solid acid catalyst: An active catalyst for the synthesis of bisphenols

    Niranjan Biswal; Dipti Prakasini Das; Kulamani Parida


    A series of novel CsTPA-ZTP ( = 30, 40, 50, 60 and 80 wt%) solid acid composite catalysts were synthesized by ion-exchange process using cesium nitrate, tungstophosphoric acid (TPA), zirconium titanium phosphate (ZTP) with varied surface areas, acidities and microstructures. Detailed characterizations of the composite catalysts were done by Powder X-ray Diffraction (PXRD), Fourier Transform Infrared (FTIR) Spectroscopy, N2 adsorption desorption, Scanning Electron Microscopy (SEM-EDS) analysis, X-ray Photoelectron Spectroscopy (XPS) and Temperature Programmed Desorption (TPD).We have studied the catalytic activities, kinetics and reusability of the catalysts. 60CsTPA-ZTP is found to be an effective and re-usable catalyst for the synthesis of bisphenol A (BPA) and bisphenol F (BPF) using acetonitrile as solvent.

  15. Solid Phase Synthesis of 2-Substituted 1,3-Oxazin-6-ones Using Resin-bound Cyclic Malonic Acid Ester

    LIU, Zhan-Xiang(刘占祥); RUAN, Xiu-Xiu(阮秀秀); HUANG, Xian(黄宪)


    A facile solid phase synthesis of 2-substituted 1,3-oxazin-6-ones using polymer-supported Meldrum's acid has been reported. Reaction of the resin-bound cyclic malonic acid ester with triethyl orthoformate and subsequent double substitution with amide, afforded the corresponding polymer-supported acylaminomethylene cyclic malonic acid ester, which upon thermal treatment led to 1, 3-oxazin-6-ones in good yields and with high purity.

  16. Characterization of Substituted Phenol-Formaldehyde Resins Using Solid-State Carbon-13 NMR


    cashew nut shell liquid , 3-n-pentadecylphenol and phenol with formaldehyde. The resulting resins were crosslinked and then investigated using...should be sent SYNOPSIS Crosslinked substituted phenol-formaldehyde resins were synthesized from cashew nut shell liquid , 3-n-pentadecylphenol and... nut shell liquid (CNSL) and are the basis for binder resins and friction particles in composite friction materials. CNSL is isolated from cashew nut

  17. D301 resin as a solid base for phosphine-free Heck reactions with heteroaryl halides

    Wen Pei; Xiang Mei Wu


    A new and practical method of the D301 resin,a weak basic anion exchange resin with secondary amine functionality (Grade Matrix Structure:Styrene-DVB D301R),used as base to Heck reactions catalyzed by palladium reagent without phosphine compound as ligand is described.It was found that the D301 resin used as base is an efficient and reusable base and can be regenerated and recycled in the reaction.The olefination of heteroaryl halides prepared the corresponding products in good yields using D301 resin as base.

  18. Catalytic hydrothermal pretreatment of corncob into xylose and furfural via solid acid catalyst.

    Li, Huiling; Deng, Aojie; Ren, Junli; Liu, Changyu; Lu, Qi; Zhong, Linjie; Peng, Feng; Sun, Runcang


    Selectively catalytic hydrothermal pretreatment of corncob into xylose and furfural has been developed in this work using solid acid catalyst (SO4(2-)/TiO2-ZrO2/La(3+)). The effects of corncob-to-water ratio, reaction temperature and residence time on the performance of catalytic hydrothermal pretreatment were investigated. Results showed that the solid residues contained mainly lignin and cellulose, which was indicative of the efficient removal of hemicelluloses from corncob by hydrothermal method. The prepared catalyst with high thermal stability and strong acid sites originated from the acid functional groups was confirmed to contribute to the hydrolysis of polysaccharides into monosaccharides followed by dehydration into furfural. Highest furfural yield (6.18 g/100g) could be obtained at 180°C for 120 min with 6.80 g/100g xylose yield when the corncob/water ratio of was 10:100. Therefore, selectively catalytic hydrothermal pretreatment of lignocellulosic biomass into important platform chemicals by solid acids is considered to be a potential treatment for biodiesel and chemical production.

  19. Synthesis of diverse indole libraries on polystyrene resin – Scope and limitations of an organometallic reaction on solid supports

    Knepper, Kerstin; Vanderheiden, Sylvia


    Summary The synthesis of diverse substituted indole structures on solid supports is described. The immobilization of nitrobenzoic acid onto Merrifield resin and the subsequent treatment with alkenyl Grignard reagents delivered indole carboxylates bound to solid supports. In contrast to results in the liquid phase, ortho,ortho-unsubstituted nitroarenes also delivered indole moieties in good yields. Subsequent palladium-catalyzed reactions (Suzuki, Heck, Sonogashira, Stille) delivered, after cleavage, the desired molecules in moderate to good yields over four steps. The scope and limitations are presented. PMID:23019447

  20. Synthesis of diverse indole libraries on polystyrene resin – Scope and limitations of an organometallic reaction on solid supports

    Kerstin Knepper


    Full Text Available The synthesis of diverse substituted indole structures on solid supports is described. The immobilization of nitrobenzoic acid onto Merrifield resin and the subsequent treatment with alkenyl Grignard reagents delivered indole carboxylates bound to solid supports. In contrast to results in the liquid phase, ortho,ortho-unsubstituted nitroarenes also delivered indole moieties in good yields. Subsequent palladium-catalyzed reactions (Suzuki, Heck, Sonogashira, Stille delivered, after cleavage, the desired molecules in moderate to good yields over four steps. The scope and limitations are presented.

  1. Comparison between liquid and solid acids catalysts on reducing sugars conversion from furfural residues via pretreatments.

    Lin, Keying; Ma, Baojun; Sun, Yuan; Liu, Wanyi


    Liquid sulphuric acid is adopted and compared with carbon-based sulfonated solid acids (coal tar-based and active carbon-based) for furfural residues conversion into reducing sugars. The optimum hydrolysis conditions of liquid acid are at 4% of sulphuric acid, 25:1 of liquid and solid ratio, 175°C of reaction temperature and 120 min of reaction time. The reducing sugar yields are reached over 60% on liquid acid via NaOH/H2O2, NaOH/microwave and NaOH/ultrasonic pretreatments, whereas only over 30% on solid acids. The TOFs (turnover number frequency) via NaOH/H2O2 pretreatments are 0.093, 0.020 and 0.023 h(-1) for liquid sulphuric acid, coal tar-based and active carbon-based solid acids catalysts, respectively. Considering the efficiency, cost and environment factors, the liquid and solid acids have their own advantages of potential commercial application values.

  2. Clean synthesis of biodiesel over solid acid catalysts of sulfonated mesopolymers


    FDU-15-SO3H,a solid acid material prepared from the sulfonation of FDU-15 mesoporous polymer,has been demonstrated to serve as an efficient catalyst in the esterification of palmitic acid with methanol as well as in the transesterification of fatty acid-edible oil mixture.FDU-15-SO3H achieved an acid conversion of 99.0% when the esterification was carried out at 343 K with a methanol/palmitic acid molar ratio of 6:1 and 5 wt% catalyst loading.It was capable of giving 99.0% yield of fatty acid methyl esters (FAME) when the transesterification of soybean oil was performed at 413 K and the methanol/oil weight ratio of 1:1.FDU-15-SO3H was further applied to the transesterification/esterification of the oil mixtures with a varying ratio of soybean oil to palmitic acid,which simulated the feedstock with a high content of free fatty acids.The yield of FAME reached 95% for the oil mixtures containing 30 wt% palmitic acid.This indicated the sulfonated mesopolymer was a potential catalyst for clean synthesis of fuel alternative of biodiesel from the waste oil without further purification.

  3. Environmentally Benign Neem Biodiesel Synthesis Using Nano-Zn-Mg-Al Hydrotalcite as Solid Base Catalysts

    Karthikeyan Chelladurai


    Full Text Available Hydrotalcite, also known as aluminum-magnesium layered double hydroxide (LDH or anionic clay, is a synthetic compound that was broadly investigated in the past decade due to its many potential applications. In this work, we present an environmentally benign process for the transesterification (methanolysis of neem oil to fatty acid methyl esters (FAME using Zn-Mg-Al hydrotalcites as solid base catalysts in a heterogeneous manner. The catalysts were characterized by XRD, FT-IR, TPD-CO2, and the BET surface area analysis. It is well-known that the catalytic performance of hydrotalcite is dramatically increased through the incorporation of Zn into the surface of Mg-Al hydrotalcite material. The optimized parameters, 10 : 1 methanol/oil molar ratio with 7.5 g catalysts reacted under stirring speed 450 rpm at 65°C for 4 h reaction, gave a maximum ester conversion of 90.5% for the sample with Zn-Mg-Al ratio of 3 : 3 : 1.

  4. An alternative preparation method for ion exchanged catalysts: Solid state redox reaction

    Schneider, E.; Hagen, A.; Grunwaldt, J.-D.


    A new method for modifying zeolites with zinc is proposed. The solid state redox reaction between metallic zinc and ZSM-5 zeolites with different Si/Al ratios was investigated by temperature programmed hydrogen evolution (TPHE), X-ray absorption near edge structure (XANES) and diffuse reflectance...... infrared Fourier transform spectroscopy (DRIFTS). The evolution of hydrogen was detected at temperatures above 620 K. The source of hydrogen was the solid state redox reaction of the metal with protons of the support. The samples exhibit catalytic activity in ethane aromatization indicating that zinc...... should be located at the same sites as in catalysts prepared by conventional methods. Combination of XANES and catalytic activity point to zinc being mainly present in tetrahedral geometry under reaction conditions....

  5. Preparation and characterization of biomass carbon-based solid acid catalyst for the esterification of oleic acid with methanol.

    Liu, Tiantian; Li, Zhilong; Li, Wei; Shi, Congjiao; Wang, Yun


    A solid acid catalyst, prepared by sulfonating carbonized corn straw, was proved to be an efficient and environmental benign catalyst for the esterification of oleic acid and methanol. Various synthetic parameters, such as carbonization temperature and time were systematically examined. It was found that the catalyst exhibited the highest acid density of 2.64 mmol/g by NaOH titration. A quantitative yield (98%) of ester was achieved, using the most active sulfonated catalyst at 333 K with a 7 wt.% catalyst/oleic acid ratio for 4h, at a 7:1 M ratio of methanol/oleic acid, while the commercial available Amberlyst-15 only gave 85% yield under the same reaction condition.

  6. Two solid-phase recycling method for basic ionic liquid [C4mim]Ac by macroporous resin and ion exchange resin from Schisandra chinensis fruits extract.

    Ma, Chun-hui; Zu, Yuan-gang; Yang, Lei; Li, Jian


    In this study, two solid-phase recycling method for basic ionic liquid (IL) 1-butyl-3-methylimidazolium acetate ([C4mim]Ac) were studied through a digestion extraction system of extracting biphenyl cyclooctene lignans from Schisandra chinensis. The RP-HPLC detection method for [C4mim]Ac was established in order to investigate the recovery efficiency of IL. The recycling method of [C4mim]Ac is divided into two steps, the first step was the separation of lignans from the IL solution containing HPD 5000 macroporous resin, the recovery efficiency and purity of [C4mim]Ac achieved were 97.8% and 67.7%, respectively. This method cannot only separate the lignans from [C4mim]Ac solution, also improve the purity of lignans, the absorption rate of lignans in [C4mim]Ac solution was found to be higher (69.2%) than that in ethanol solution (57.7%). The second step was the purification of [C4mim]Ac by the SK1B strong acid ion exchange resin, an [C4mim]Ac recovery efficiency of 55.9% and the purity higher than 90% were achieved. Additionally, [C4mim]Ac as solvent extraction of lignans from S. chinensis was optimized, the hydrolysis temperature was 90°C and the hydrolysis time was 2h.

  7. A Green Synthesis of 2-Ethylanthraquinone by Dehydration of 2-(4'-ethylbenzoyl) benzoic Acid over Solid Acid Catalysts

    Ren Shu XU; Xin Wen GUO; Gui Ru WANG; Zhu Xia ZHANG


    The dehydration of 2-(4'-ethylbenzoyl) benzoic acid (BE acid) to 2-ethylanthraquinone(2-EAQ) was investigated over solid acid catalysts. The results showed that H-beta zeolite catalyst modified by dilute HNO3 solution exhibited an excellent performance. In our study, theconversion of BE acid can reach 96.7%, and the selectivity to 2-EAQ is up to 99.6%.

  8. Novel magnetic porous carbon spheres derived from chelating resin as a heterogeneous Fenton catalyst for the removal of methylene blue from aqueous solution.

    Ma, Junjun; Zhou, Lincheng; Dan, Wenfeng; Zhang, He; Shao, Yanming; Bao, Chao; Jing, Lingyun


    Porous magnetic carbon spheres (MCS) were prepared from carbonized chelating resin composites derived from ethylenediaminetetraacetic acid-modified macroporous polystyrene (PS-EDTA) resin, and then loaded with iron composites via ion exchange. The resulting composites were characterized for this study using X-ray diffraction, MÖssbauer spectroscopy, and Raman spectroscopy, X-ray photoelectron spectroscopy, Brunauer-Emmett-Teller surface area method, scanning electron microscopy, and vibrating sample magnetometry. The porous magnetic carbon spheres were then used, in the existence of H2O2 and NH2OH, with a view to remove methylene blue from the aqueous solution by catalyze a heterogeneous Fenton reaction. Results indicated excellent removal rates and removal efficiency for this catalytic system. Optimal degradation was achieved (nearly 100% within 10 min) using initial concentrations of 5 mmol H2O2 L(-1), 2.5 mmol L(-1) NH2OH and 40 mg L(-1) methylene blue. The catalyst retained its activity after six reuses, indicating strong stability and reusability. Porosity of the catalyst contributed to its high activity, suggesting its potential application for the industrial treatment of wastewater.

  9. Effect Of Solid Acids In The Conversion Of Glycerol Over Ru/Bentonite Catalyst In Glycerol Hydrogenolysis Reaction

    Noraini Hamzah


    Full Text Available Glycerol known as by-product of transesterification of vegetables oil become an important materials after some chemical modification. In this study, hydrogenolysis reaction of glycerol to 1,2-propanediol was conducted using various supported ruthenium based catalyst. The support materials used in this study are bentonite ,TiO2, Al2O3 and SiO2. All experiments were carried out at reaction condition of 150°C, hydrogen pressure 20-30 bar for 7 hours and the 20%(wt glycerol content in distilled water. The result shows that activity of the catalyts increased following this order: Ru/SiO2< Ru/TiO2 ≈ Ru/Al2O3 < Ru/bentonite. High selectivity to 1,2-propanediol was obtained in hydrogenolysis glycerol over Ru/TiO2 (83.7% and Ru/bentonite (80.1% catalysts. Since Ru/bentonite catalyst performed better than other tested catalyst, we choose this catalyst system to investigate the effect of various solid acids (zeolite, ZrO2, Nb2O5 and amberlyst on conversion of glycerol in hydrogenolysis reaction. Addition of solid acid in hydrogenolysis glycerol had promote the activity of Ru/bentonite catalyst drastically. The result shows that the presence of zeolite make the conversion of glycerol increased to maximum from 62.8% to 81.6% compared the other solid acids. Interestingly, selectivity to 1,2-propanediol still was achieved over 80.0%. These catalysts system were characterized by XRD, XPS, BET, and TEM for obtaining some physicochemical properties of the catalysts.

  10. New Stable Cu(I) Catalyst Supported on Weakly Acidic Polyacrylate Resin for Green C-N Coupling: Synthesis of N-(Pyridin-4-yl)benzene Amines and N,N-Bis(pyridine-4-yl)benzene Amines.

    Kore, Nitin; Pazdera, Pavel


    A method for preparation of a new stable Cu(I) catalyst supported on weakly acidic polyacrylate resin without additional stabilizing ligands is described. A simple and efficient methodology for Ullmann Cu(I) catalyzed C-N cross coupling reactions using this original catalyst is reported. Coupling reactions of 4-chloropyridinium chloride with anilines containing electron donating (EDG) or electron withdrawing (EWG) groups, naphthalen-2-amine and piperazine, respectively, are successfully demonstrated.

  11. New Stable Cu(I Catalyst Supported on Weakly Acidic Polyacrylate Resin for Green C-N Coupling: Synthesis of N-(Pyridin-4-ylbenzene Amines and N,N-Bis(pyridine-4-ylbenzene Amines

    Nitin Kore


    Full Text Available A method for preparation of a new stable Cu(I catalyst supported on weakly acidic polyacrylate resin without additional stabilizing ligands is described. A simple and efficient methodology for Ullmann Cu(I catalyzed C-N cross coupling reactions using this original catalyst is reported. Coupling reactions of 4-chloropyridinium chloride with anilines containing electron donating (EDG or electron withdrawing (EWG groups, naphthalen-2-amine and piperazine, respectively, are successfully demonstrated.

  12. Simultaneous production of high quality biodiesel and glycerin from Jatropha oil using ion-exchange resins as catalysts and adsorbent.

    Shibasaki-Kitakawa, Naomi; Kanagawa, Keiichi; Nakashima, Kazunori; Yonemoto, Toshikuni


    The simultaneous production of high quality biodiesel and glycerin was realized by a bench-scale process using expanded-bed reactors packed with cation- and anion-exchange resins. The mixed-solution of crude Jatropha oil and methanol at a stoichiometric molar ratio was supplied to the process. The free fatty acid as well as triglyceride was completely converted to biodiesel. All by-products were adsorbed on the resin and the effluent from the process was free from them. The effluent fully met the international biodiesel standard specifications without any downstream purification processes except for removing methanol. The glycerin adsorbed on the resin was completely recovered as a transparent methanol solution during regeneration of the resin.

  13. Relationship between surface acidity and activity of solid-acid catalysts in vapour phase dehydration of methanol

    Mollavali, M.; Atashi, H. [Department of Chemical Engineering, Faculty of Engineering, University of Sistan and Baluchestan, P.O. Box 98164-161, Zahedan (Iran); Yaripour, F.; Mohammadi-Jam, S. [Catalyst Research Group, Petrochemical Research and Technology Company, National Petrochemical Company, 14358, Tehran (Iran)


    A series of solid-acid catalysts comprised of {gamma}-alumina and modified {gamma}-alumina with different of silica were prepared by co-precipitation method. The catalysts were characterized using XRD, TGA, NH{sub 3}-TPD and BET techniques. Dehydration of methanol to dimethyl ether (DME) on solid-acid catalysts was studied in a fixed-bed reactor at the same operating conditions (T = 300 C, P = 16 bar, WHSV = 26.07 h{sup -} {sup 1}). According to the experimental results, silica-modified catalysts have shown better performance compared to the pure {gamma}-alumina. It was found that surface areas increase with increasing silica loading. The results of NH{sub 3}-TPD analysis showed that the surface acidity of aluminosilicate catalysts increases with increase in SiO{sub 2}/Al{sub 2}O{sub 3} molar ratio. Also, it was found that the catalysts with highest portion of weak and/or moderate acid sites exhibit the best catalytic performance and stability. The sample with 3 wt.% silica loading has exhibited the best activity for methanol conversion. (author)

  14. High solids loading of aluminum nitride powder in epoxy resin: Dispersion and thermal conductivity

    Lee, Eunsung

    Most semiconductor devices are now packaged in an epoxy polymer composite, which includes a silica powder filler for reducing the thermal expansion coefficient. However, increased heat output from near-future semiconductors will require higher thermal conductivity fillers such as aluminum nitride powder, instead of silica. This thesis research is intended to apply improved dispersant chemistry, in order to achieve a high volume percentage of AlN powder in epoxy, increasing the thermal conductivity of the composite without causing excessive viscosity before the epoxy monomer is crosslinked. In initial experiments, the dispersibility of aluminum oxide in epoxy monomer resin was better than that of AlN, because of the weaker basicity of oxide surfaces compared with nitride. To improve the dispersibility of AlN, its surface was modified by pretreatment with silane coupling agents. Silane molecules with different head groups were investigated. In those experiments, methylsilane gave lower viscosities than chloro- or methoxysilane, while pretreatments using organic acids increased the viscosity of the AlN dispersion. The viscosity changes and FTIR peak intensity trends suggested that the silane molecules could be adsorbed on AlN surfaces in the form of a monolayer during optimization experiments, and the best silane monolayer coverage on the AlN powder surfaces was achieved with 2 wt% amounts in a 3 hour treatment. A particular phosphate ester was a good second layer dispersant for the AlN-plus-epoxy system. When that dispersant was added onto the silane-treated filler surfaces, the degree of viscosity reduction was dependent on the types of silane coupling agent functional groups. In the optimized results, silane pretreatment followed by dispersant addition was better than either alone. High solids loading, up to 57 vol.%, was achieved with a wide particle size distribution of powder, and the viscosity of that dispersion was 60,000 to 90,000 cps, which easily flowed by

  15. Modified calcium oxide as stable solid base catalyst for Aldol condensation reaction

    Ying Tang; Jingfang Xu; Xuefan Gu


    A highly efficient and stable solid-base catalyst for Aldol condensation was prepared by modifying commercial CaO with benzyl bromide in a simple way. It was found that modified CaO can effectively catalyse the Aldol condensation of cyclohexanone and benzaldehyde, as well as various benzaldehydes, to produce 2-benzylidenecyclohexanone with a good selectivity and high yield. Higher yield of 95.8% was obtained over modified CaO after 3 h, which is short compared with the yield of 92.1% after 12 h over commercial CaO. The influence of several reaction parameters, such as temperature, catalyst loading, was investigated. The humidity test over modified CaO reveals that the basic centres of modified CaO are stable for CO2 and moisture. From the results of Fourier transform-infrared (FT-IR) and Thermogravity analysis (TG) characterization, the modifier was bonded on surface of CaO chemically and almost no Ca(OH)2 formed during the modification process. The type of aldehyde has great influence on the yield of aldol condensation.

  16. Nanocasting Design and Spatially Selective Sulfonation of Polystyrene-Based Polymer Networks as Solid Acid Catalysts.

    Richter, Felix H; Sahraoui, Laila; Schüth, Ferdi


    Nanocasting is a general and widely applied method in the generation of porous materials during which a sacrificial solid template is used as a mold on the nanoscale. Ideally, the resulting structure is the inverse of the template. However, replication is not always as direct as anticipated, so the influences of the degree of pore filling and of potential restructuring processes after removal of the template need to be considered. These apparent limitations give rise to opportunities in the synthesis of poly(styrene-co-divinylbenzene) (PSD) polymer networks of widely varying porosities (BET surface area=63-562 m(2)  g(-1) ; Vtot =0.18-1.05 cm(3)  g(-1) ) by applying a single synthesis methodology. In addition, spatially selective sulfonation on the nanoscale seems possible. Together, nanocasting and sulfonation enable rational catalyst design. The highly porous nanocast and predominantly surface-sulfonated PSD networks approach the activity of the corresponding molecular catalyst, para-toluenesulfonic acid, and exceed those of commercial ion-exchange polymers in the depolymerization of macromolecular inulin.

  17. Supported organoiridium catalysts for alkane dehydrogenation

    Baker, R. Thomas; Sattelberger, Alfred P.; Li, Hongbo


    Solid supported organoiridium catalysts, a process for preparing such solid supported organoiridium catalysts, and the use of such solid supported organoiridium catalysts in dehydrogenation reactions of alkanes is provided. The catalysts can be easily recovered and recycled.

  18. Preparation and Catalytic Application of Novel Water Tolerant Solid Acid Catalysts of Zirconium Sulfate/HZSM-5

    JIANG Ya-jie; JUAN Joon Ching; MENG Xiu-juan; CAO Wei-liang; YARMO Mohd Ambar; ZHANG Jing-chang


    Esterification of acrylic acid(AA) to produce AA esters has widespread application in the chemical industry. A series of water tolerant solid acid catalysts was prepared, and characterized by XRD, nitrogen adsorption, TGA-DTA, XPS, and ammonia adsorption FTIR. The effects of Si/Al ratio, zirconium sulfate(ZS) loading on HZSM-5 and calcination temperature on the esterification were investigated. When 20%(mass fraction) ZS is loaded on HZSM-5, the conversion of AA reaches 100%. XRD analysis indicates that ZS is highly dispersed on HZSM-5 because no crystalline structure assigned to ZS is found. Catalytic activity and hydrophobicity of ZS supported on HZSM-5 are higher compared with those of parent ZS or HZSM-5. Results show that this kind of novel catalysts is an efficient water tolerant solid acid catalyst for esterification reactions.

  19. Solid-phase peptide synthesis of endothelin receptor antagonists on novel flexible, styrene-acryloyloxyhydroxypropyl methacrylate-tripropyleneglycol diacrylate [SAT] resin.

    Siyad, M A; Nair, Arun S V; Kumar, G S Vinod


    Novel cross-linked polymeric support by the copolymerization of styrene and 3-(acryloyloxy)-2-hydroxypropyl methacrylate with Tri(propyleneglycol) diacryalte (SAT) for solid-phase peptide synthesis is presented here. The synthesis of SAT is based on the cross-linking of 3-(acryloyloxy)-2-hydroxypropyl methacrylate with styrene by free-radical suspension polymerization, consisting of an ester and a secondary hydroxyl group. An additional cross-linker tri(propyleneglycol) diacryalte provides a hydrophilic environment throughout the resin, which will enhance the physicochemical properties of the resin toward organic synthesis. The resins were synthesized in various cross-linking densities to check the swelling property, mechanical stability, and functional loading capacity. The resin was characterized by the IR, (13)C NMR, and SEM techniques. The extent of swelling properties of the polymer of different cross-linking densities were studied and compared with Merrifield resin and TentaGel. To demonstrate the efficiency of SAT support was proved by synthesizing the challenging peptide sequence of acyl carrier protein (ACP) and compared with commercially available Merrifield resin. It was further tested by synthesizing endothelial receptor antagonist peptides using SAT resin and compared with commercially available TentaGel resin. The standard Fmoc strategy was adopted for peptide synthesis and was characterized by MALDI-TOF MS and analyzed the purity of peptides by HPLC.

  20. Diameter-Specific Growth of Semiconducting SWNT Arrays Using Uniform Mo2C Solid Catalyst.

    Zhang, Shuchen; Tong, Lianming; Hu, Yue; Kang, Lixing; Zhang, Jin


    Semiconducting single-walled nanotube (s-SWNT) arrays with specific diameters are urgently demanded in the applications in nanoelectronic devices. Herein, we reported that by using uniform Mo2C solid catalyst, aligned s-SWNT (∼90%) arrays with narrow-diameter distribution (∼85% between 1.0 and 1.3 nm) on quartz substrate can be obtained. Mo2C nanoparticles with monodisperse sizes were prepared by using molybdenum oxide-based giant clusters, (NH4)42[Mo132O372(H3CCOO)30(H2O)72]·10H3CCOONH4·300H2O(Mo132), as the precursor that was carburized by a gas mixture of C2H5OH/H2 during a temperature-programmed reduction. In this approach, the formation of volatile MoO3 was inhibited due to the annealing and reduction at a low temperature. As a result, uniform Mo2C nanoparticles are formed, and their narrow size-dispersion strictly determines the diameter distribution of SWNTs. During the growth process, Mo2C selectively catalyzes the scission of C-O bonds of ethanol molecules, and the resultant absorbed oxygen (Oads) preferentially etches metallic SWNTs (m-SWNTs), leading to the high-yield of s-SWNTs. Raman spectroscopic analysis showed that most of the s-SWNTs can be identified as (14, 4), (13, 6), or (10, 9) tubes. Our findings open up the possibility of the chirality-controlled growth of aligned-SWNTs using uniform carbide nanoparticles as solid catalysts for practical nanoelectronics applications.

  1. Selective Aerobic Oxidation of 5-Hydroxymethylfurfural in Water Over Solid Ruthenium Hydroxide Catalysts with Magnesium-Based Supports

    Gorbanev, Yury; Kegnæs, Søren; Riisager, Anders


    Solid catalyst systems comprised of ruthenium hydroxide supported on magnesium-based carrier materials (spinel, magnesium oxide and hydrotalcite) were investigated for the selective, aqueous aerobic oxidation of the biomass-derived chemical 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid...

  2. Developing a Thermal- and Coking-Resistant Cobalt-Tungsten Bimetallic Anode Catalyst for Solid Oxide Fuel Cells

    Yan, N.; Pandey, J.; Zeng, Y.; Amirkhiz, B.S.; Hua, B.; Geels, N.J.; Luo, J.L.; Rothenberg, G.


    We report the development of a novel Co–W bimetallic anode catalyst for solid oxide fuel cells (SOFCs) via a facile infiltration-annealing process. Using various microscopic and spectroscopic measurements, we find that the formed intermetallic nanoparticles are highly thermally stable up to 900 °C

  3. Deactivation of solid catalysts in liquid media: the case of leaching of active sites in biomass conversion reactions

    Sádaba, Irantzu; Lopez Granados, Manuel; Riisager, Anders;


    This review is aimed to be a brief tutorial covering the deactivation of solid catalysts in the liquid phase, with specific focus on leaching, which can be especially helpful to researchers not familiarized with catalytic processes in the liquid phase. Leaching refers to the loss of active specie...

  4. Metal nanoparticles immobilized on ion-exchange resins:A versatile and effective catalyst platform for sustainable chemistry

    Francesca Liguori; Carmen Moreno-Marrodan; Pierluigi Barbaro


    This paper reviews the recent achievements in the immobilization of metal nanoparticles on ion-exchange resins and the related catalytic application. The focus is on the production processes for fine and commodity chemicals for which a low environmental impact has been demonstrated. The most significant papers that appeared in the literature from January 2010 to July 2014 have been covered. Their uses in unselective processes, bulk chemicals production, fuel cells compo-nents, as well as the use of metal-free ion-exchange resins in acid/base-catalysed reactions, were not included.

  5. Development of molecular and solid catalysts for the direct low-temperature oxidation of methane to methanol.

    Palkovits, Regina; von Malotki, Christian; Baumgarten, Martin; Müllen, Klaus; Baltes, Christian; Antonietti, Markus; Kuhn, Pierre; Weber, Jens; Thomas, Arne; Schüth, Ferdi


    The direct low-temperature oxidation of methane to methanol is demonstrated on a highly active homogeneous molecular catalyst system and on heterogeneous molecular catalysts based on polymeric materials possessing ligand motifs within the material structure. The N-(2-methylpropyl)-4,5-diazacarbazolyl-dichloro-platinum(II) complex reaches significantly higher activity compared to the well-known Periana system and allows first conclusions on electronic and structural requirements for high catalytic activity in this reaction. Interestingly, comparable activities could be achieved utilizing a platinum modified poly(benzimidazole) material, which demonstrates for the first time a solid catalyst with superior activity compared to the Periana system. Although the material shows platinum leaching, improved activity and altered electronic properties, compared to the conventional Periana system, support the proposed conclusions on structure-activity relationships. In comparison, platinum modified triazine-based catalysts show lower catalytic activity, but rather stable platinum coordination even after several catalytic cycles. Based on these systems, further development of improved solid catalysts for the direct low-temperature oxidation of methane to methanol is feasible.

  6. Pyroacm Resin: An Acetamidomethyl Derived Resin for Solid Phase Synthesis of Peptides through Side Chain Anchoring of C-Terminal Cysteine Residues.

    Juvekar, Vinayak; Gong, Young Dae


    The design, synthesis and utilization of an efficient acetamidomethyl derived resin for the peptide synthesis is presented using established Fmoc and Boc protocols via side chain anchoring. Cleavage of the target peptide from the resin is performed using carboxymethylsulfenyl chloride under mild conditions which gave in situ thiol-sulfenyl protection of the cysteine residues. The utility of the resin is successfully demonstrated through applications to the syntheses of model peptides and natural products Riparin 1.1 and Riparin 1.2.

  7. Utilization of eggshell waste as low-cost solid base catalyst for biodiesel production from used cooking oil

    Asri, N. P.; Podjojono, B.; Fujiani, R.; Nuraini


    A solid CaO-based catalyst of waste eggshell was developed for biodiesel production from used cooking oil. The waste eggshell powder was calcined in air at 90° C for 4 h to convert calcium species in the eggshells into active CaO catalysts. The characterization of CaO catalyst was done by XRD and BET analysis. The CaO catalyst was then introduced for transesterification of used cooking oil (UCO) for testing of its catalytic activity. The experiment was conducted in batch type reactor that consists of three-neck glass equipped by reflux condenser and magnetic stirrer. Before tranesterification process, the UCO was treated by coconut coir powder in order to reduce the free fatty acid content. The result showed that the catalyst was potentially use for transesterification of used cooking oil into biodiesel with relatively high yield of 75.92% was achieved at reaction temperature, reaction time, molar ratio UCO to methanol and catalyst amount of 65° C, 7 h, 1:15 and 6%, respectively.

  8. Promoter of (Ce-Zr)O2 Solid Solution Modified by Praseodymia in Three-Way Catalysts

    汪文栋; 林培琰; 孟明; 伏义路; 胡天斗; 谢亚宁; 刘涛


    The three-way catalysts (TWCs) promoters (Ce-Zr)O2, (Pr-Ce-Zr)O2 and (Pr-Zr)O2 were prepared by sol-gel like method. They were characterized by XRD, EXAFS and BET surface area determination. The reduction features of the promoters were measured by temperature-programmed reduction (TPR) of H2 to access the potential for the promoters containing praseodymia as oxygen storage component in three-way catalyst. The (Pr-Zr)O2 cubic solid solution is formed at high temperature up to 800 ℃, which makes it more reducible than the (Ce-Zr)O2 solid solution. For the (Pr-Ce-Zr)O2 samples, the ternary solid solution plays an important role in the reduction process. The performance of the three-way catalysts with fully formulated Pt, Pd and Rh is proceeded by using both light-off temperature under a stoichiometric gas composition and the conversion of CO, C3H6 and NO under changing air/fuel ratio at a constant reaction temperature 400 ℃. The results indicate that a small amount of praseodymia doping into (Ce-Zr)O2 favors the light-off temperature of C3H6 and NO, and all the catalysts containing praseodymia obviously exhibits enhanced width of S value for NO conversion at lean region (S≥1.00).

  9. Effective immobilisation of a metathesis catalyst bearing an ammonium-tagged NHC ligand on various solid supports

    Krzysztof Skowerski


    Full Text Available An ammonium-tagged ruthenium complex, 8, was deposited on several widely available commercial solid materials such as silica gel, alumina, cotton, filter paper, iron powder or palladium on carbon. The resulting catalysts were tested in toluene or ethyl acetate, and found to afford metathesis products in high yield and with extremely low ruthenium contamination. Depending on the support used, immobilised catalyst 8 shows also additional traits, such as the possibility of being magnetically separated or the use for metathesis and subsequent reduction of the obtained double bond in one pot.

  10. Physiochemical characterization of taste masking levetiracetam ion exchange resinates in the solid state and formulation of stable liquid suspension for pediatric use

    Sivaneswari S.


    Full Text Available In the present work, an attempt has been made to mask the bitter taste of Levetiracetam using various ion-exchange resins such as Amberlite IRP69 and Duolite AP143. The physicochemical characteristics of the drug–resin complex in the solid state were studied. FT-IR studies revealed that there is no interaction between drug and resin. The DSC and XRD studies proved that the drug is in amorphous nature. Using the same concentration of resins, Xanthan gum as suspending agent in a liquid dosage form for pediatric use was formulated. Evaluation parameters such as drug content, sedimentation volume, re-dispersibility and viscosity of the prepared suspension were found to be satisfactory. The higher Zeta potential value indicates the stability of the suspension. Suspension prepared with Duolite AP 143 efficiently masks the bitter taste of Levetiracetam compared to Amberlite IRP69. From the in vitro drug release, a formulation with 1:2 ratios of resin has shown the maximum release at the end of 90 minutes. The sustained effect is due to one of the properties of the resin. The release profile follows zero order kinetics. The results obtained in this work show that drug–resin complexes effectively masked the bitter taste of Levetiracetam while liquid formulation provides an easier way to administer and to overcome problems with noncompliance of pediatrics.

  11. Adsorption of Rh(III) complexes from chloride solutions obtained by leaching chlorinated spent automotive catalysts on ion-exchange resin Diaion WA21J

    Shen Shaobo, E-mail: [Key Laboratory of Ecological and Recycling Metallurgy, Ministry of Education of China, Beijing 100083 (China); Department of Physical Chemistry, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Pan Tonglin; Liu Xinqiang; Yuan Lei [Key Laboratory of Ecological and Recycling Metallurgy, Ministry of Education of China, Beijing 100083 (China); Wang Jinchao [Key Laboratory of Ecological and Recycling Metallurgy, Ministry of Education of China, Beijing 100083 (China); Department of Physical Chemistry, School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhang Yongjian; Guo Zhanchen [Key Laboratory of Ecological and Recycling Metallurgy, Ministry of Education of China, Beijing 100083 (China)


    It was found that Rh, Pd and Pt contained in the spent ceramic automotive catalysts could be effectively extracted by dry chlorination with chlorine. In order to concentrate Rh(III) ions contained in the chloride solutions obtained, thermodynamic and kinetics studies for adsorption of Rh(III) complexes from the chloride solutions on an anionic exchange resin Diaion WA21J were carried out. Rh, Pd, Pt, Al, Fe, Si, Zn and Pb from the chloride solution could be adsorbed on the resin. The distribution coefficients (K{sub d}) of Rh(III) decreased with the increase in initial Rh(III) concentration or in adsorption temperature. The isothermal adsorption of Rh(III) was found to fit Langmuir, Freundlich and Dubinin-Kaganer-Radushkevich models under the adsorption conditions. The maximum monolayer adsorption capacities Q{sub max} based on Langmuir adsorption isotherms were 6.39, 6.61 and 5.81 mg/g for temperatures 18, 28 and 40 deg. C, respectively. The apparent adsorption energy of Rh was about -7.6 kJ/mol and thus Rh(III) adsorption was a physical type. The experimental data obtained could be better simulated by pseudo-first-order kinetic model and the activation energy obtained was 6.54 J/mol. The adsorption rate of Rh(III) was controlled by intraparticle diffusion in most of time of adsorption process.

  12. Liquid-phase benzene isopropylation using alumina solid lewis superacid-supported platinum catalyst

    Yamada, K.; Honda, K.; Kitahara, D.; Miyamoto, M.; Shiga, M.; Ayame, A. [Muroran Inst. of Tech., Hokkaido (Japan)


    Supporting platinum on alumina solid Lewis superacid (AmLSA; J. C. S., Chem. Commun., 645 (1989)) was prepared by using of the in situ CVD technique at 773 K with Ar{sup +}-sputtered platinum fine particles and dry chlorine, followed by reduction with hydrogen at 673 K. The AmLSA-supported platinum catalyst (Pt/AmLSA) was applied to isopropylation of benzene with propene in the hydrogen stream at ambient temperature, using a semibatch reactor. Products were mono-, di-, tri-, and tetra-isopropylbenzenes. Conversion of propene to propane was below 1 %, and a trace amount of cyclohexane from benzene was also observed. Deactivation of AmLSA due to strong adsorption of poly-substituted benzenes and/or propene oligomers was remarkably depressed by supporting platinum and supplying hydrogen into the propene stream. Consequently, the activity of Pt/AmLSA catalyst had increased almost 1.5 times that of AmLSA. At the same level of benzene conversion, the product distribution f isopropyl-substituted benzenes obtained on Pt/AmLSA was identical to that on AmLSA, and had shifted slightly into the mono-substituted benzene side compared with the result on AmLSA in the absence of hydrogen. In the isopropylation of benzene with 2-chloropropane, the results quite similar to those described above were obtained. From the above observations, synergetic effects of platinum supporting and hydrogen supplying were considered to be due to the presence of hydrogen atoms spilled over from the platinum surface to the strong Lewis acid sites. (author)


    HuWeibing; ZhangShengming; 等


    Sereral Pd-SnO2/D3520 and Pd-PbO/D3520 catalysts with Pd/D3520,SnO2/D3520 and PbO/D3520 catalysts as reference were studied by means of IR and XPS.Interaction between Pd and the second metal or between metal and support was observed.Results show that there is a strong interaction between Pd and the second metal,but there is not an obvious interaction between metal and support.The active constituent is Pd.Hydrogenation activity of the catalysts is altered because of the interaction between Pd and the second metal.The activity of the catalysis for hydrogenation has relation to outer layer valence electron density of Pd.

  14. Properties and efficiency of a Pt/Al2O3 catalyst applied in a solid fuel thermo-accumulating furnace



    Full Text Available A prototype of a solid fuel thermo-accumulating furnace has been developed. In order to achieve a higher combustion efficiency, a Pt/Al2O3 catalyst in the form of 3 ± 0.3 mm spheres was applied, which enabled further combustion of flue gases within the furnace. Experimental investigation of the influence of the catalyst on the conversion of CO has been done for different operation regimes and positions of the catalyst. Paper presents selected results regarding CO emission during wood and coal combustion. Investigations suggest a considerable effect of the catalyst and a strong influence of the catalyst position to CO emission reduction. The microstructure of the catalyst beads, characterized by selective chemisorption of CO, has shown the decrease of the number of Pt sites as a consequence of blockage by coke deposits formed during the combustion of solid fuel.

  15. Solid-Phase Organic Synthesis and Catalysis: Some Recent Strategies Using Alumina, Silica, and Polyionic Resins

    Basudeb Basu; Susmita Paul


    Solid-phase organic synthesis (SPOS) and catalysis have gained impetus after the seminal discovery of Merrifield’s solid-phase peptide synthesis and also because of wide applicability in combinatorial and high throughput chemistry. A large number of organic, inorganic, or organic-inorganic hybrid materials have been employed as polymeric solid supports to promote or catalyze various organic reactions. This review article provides a concise account on our approaches involving the use of (i) al...

  16. A Novel Way to Prepare γ-Al2O3 Supported SO42-/ZrO2 Solid Superacid Catalysts for n-Butane Isomerization


    Highly active solid superacid catalysts for n-butane isomerization, SZ/Al2O3-P, were prepared by supporting SO42-/ZrO2 (SZ) on γ-Al2O3 carrier using a precipitation method.The activities of some catalysts were enhanced significantly.The activity of the most active sample, 60%SZ/Al2O3-P, was even about 2 times more active than that of the SZ catalyst.

  17. Efficient formation of luminescent lanthanide(III) complexes by solid-phase synthesis and on-resin screening.

    Nakamura, Tatsuya; Mizukami, Shin; Tanaka, Miho; Kikuchi, Kazuya


    Time-resolved luminescence measurements of luminescent lanthanide complexes have advantages in biological assays and high-throughput screening, owing to their high sensitivity. In spite of the recent advances in their energy-transfer mechanism and molecular-orbital-based computational molecular design, it is still difficult to estimate the quantum yields of new luminescent lanthanide complexes. Herein, solid-phase libraries of luminescent lanthanide complexes were prepared through amide-condensation and Pd-catalyzed coupling reactions and their luminescent properties were screened with a microplate reader. Good correlation was observed between the time-resolved luminescence intensities of the solid-phase libraries and those of the corresponding complexes that were synthesized by using liquid-phase chemistry. This method enabled the rapid and efficient development of new sensitizers for Sm(III), Eu(III), and Tb(III) luminescence. Thus, solid-phase combinatorial synthesis combined with on-resin screening led to the discovery of a wide variety of luminescent sensitizers.

  18. Assessment of microcapsule—catalyst particles healing system in high performance fibre reinforced polymer composite

    Bolimowski, P. A.; Wass, D. F.; Bond, I. P.


    Autonomous self-healing in carbon fibre reinforced polymer (CFRP) is demonstrated using epoxy resin filled microcapsules and a solid-state catalyst. Microcapsules filled with oligomeric epoxy resin (20-450 μm) and particles of Sc(OTf)3 are embedded in an interleave region of a unidirectional CFRP laminate and tested under mode I loading. Double cantilever beam (DCB) test specimens containing variable concentrations of microcapsules and catalyst were prepared, tested and compared to those healed by manual injection with corresponding healing resin formulation. The healing efficiency was evaluated by comparing the maximum peak load recorded on load-displacement curves for pristine and healed specimens. A 44% maximum recovery was observed for specimens containing 10 wt% of solid phase catalyst and 11 wt% of epoxy microcapsules. However, a significant (80%) decrease in initial strain energy release rate (G IC) was observed for specimens with the embedded healing chemistries.

  19. Antisolvent Precipitation for the Synthesis of Monodisperse Mesoporous Niobium Oxide Spheres as Highly Effective Solid Acid Catalysts

    Li, Cheng Chao


    We have developed a low-cost reaction protocol to synthesize mesoporous Nb 2O 5-based solid acid catalysts with external shape control. In the synthesis, monodisperse glycolated niobium oxide spheres (GNOS) were prepared by means of a simple antisolvent precipitation approach and subsequently converted to mesoporous niobium oxide spheres (MNOS) with a large surface area of 312m 2g -1 by means of the hydrothermal treatment. The antisolvent acetone used to obtain GNOS was recovered through distillation at high purity. The obtained mesoporous MNOS were functionalized further with sulfate anions at different temperatures or incorporated with tungstophosphoric acid to obtain recyclable solid acid catalysts. These MNOS-based catalysts showed excellent performance in a wide range of acid-catalyzed reactions, such as Friedel-Crafts alkylation, esterification, and hydrolysis of acetates. As they are monodisperse spheres with diameters in the submicrometer range, the catalysts can be easily separated and reused. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Synthesis of a Sulfonated Two-Dimensional Covalent Organic Framework as an Efficient Solid Acid Catalyst for Biobased Chemical Conversion.

    Peng, Yongwu; Hu, Zhigang; Gao, Yongjun; Yuan, Daqiang; Kang, Zixi; Qian, Yuhong; Yan, Ning; Zhao, Dan


    Because of limited framework stability tolerance, de novo synthesis of sulfonated covalent organic frameworks (COFs) remains challenging and unexplored. Herein, a sulfonated two-dimensional crystalline COF, termed TFP-DABA, was synthesized directly from 1,3,5-triformylphloroglucinol and 2,5-diaminobenzenesulfonic acid through a previously reported Schiff base condensation reaction, followed by irreversible enol-to-keto tautomerization, which strengthened its structural stability. TFP-DABA is a highly efficient solid acid catalyst for fructose conversion with remarkable yields (97 % for 5-hydroxymethylfurfural and 65 % for 2,5-diformylfuran), good chemoselectivity, and good recyclability. The present study sheds light on the de novo synthesis of sulfonated COFs as novel solid acid catalysts for biobased chemical conversion. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Essential role of catalysts (Mn, Au, and Sn) in the vapor liquid solid growth kinematics of ZnS nanowires

    Rehman, S.; Shehzad, M. A.; Hafeez, M.; Bhatti, A. S., E-mail: [Center for Micro and Nano Devices (CMND), Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000 (Pakistan)


    In this paper, we demonstrate that surface energy of the catalyst is a vital parameter for the growth rate, self doping of the self assembled nanowires synthesized by employing vapor liquid solid growth technique. The synthesis of ZnS nanowires was done by selectively using three different catalysts (Mn, Au, and Sn), where Au, is the most common catalyst, was used as a reference. The distinctive difference in the growth rate was due to the surface energy of the metal alloy droplet and the interface energies, as explained theoretically using thermodynamic approach. We have found that the activation energy of diffusion of (Zn, S) species in the catalyst droplet was low in Sn (0.41 eV for Zn and 0.13 eV for S) and high in Mn (1.79 eV for Zn and 0.61 eV for S) compared to Au (0.62 eV for Zn and 0.21 eV for S) catalyzed ZnS nanostructures. The thermodynamic calculations predicted the growth rates of Sn (7.5 nm/s) catalyzed nanowires was faster than Au (5.1 nm/s) and Mn (4.6 nm/s) catalyzed ZnS nanostructures, which were in agreement with the experimental results. Finally, the location of the catalyst as dopant in the grown nanostructure was predicted and compared with experimental observations.

  2. High performance air electrode for solid oxide regenerative fuel cells fabricated by infiltration of nano-catalysts

    Lee, Sung-il; Kim, Jeonghee; Son, Ji-Won; Lee, Jong-Ho; Kim, Byung-Kook; Je, Hae-June; Lee, Hae-Weon; Song, Huesup; Yoon, Kyung Joong


    A high performance air electrode fabricated by infiltration of highly active nano-catalysts into a porous scaffold is demonstrated for high-temperature solid oxide regenerative fuel cells (SORFCs). The nitrate precursor solution for Sm0.5Sr0.5CoO3 (SSC) catalyst is impregnated into a porous La0.6Sr0.4Co0.2Fe0.8O3 (LSCF)-gadolinia-doped ceria (GDC) composite backbone, and extremely fine SSC nano-particles are uniformly synthesized by in-situ crystallization at the initial stage of SORFC operation via homogeneous nucleation induced by urea decomposition. The SSC nano-catalysts are in the size range of 40-80 nm and stable against coarsening upon the SORFC operation at 750 °C. The electrochemical performance is significantly improved by incorporation of SSC nano-catalysts in both power generation and hydrogen production modes. Systematic analysis on the impedance spectra reveals that the surface modification of the air electrode with nano-catalysts remarkably accelerates the chemical surface exchange reactions for both O2 reduction and O2- oxidation, which are the major limiting processes for SORFC performance.

  3. Direct production of biodiesel from high-acid value Jatropha oil with solid acid catalyst derived from lignin

    Pua Fei-ling


    Full Text Available Abstract Background Solid acid catalyst was prepared from Kraft lignin by chemical activation with phosphoric acid, pyrolysis and sulfuric acid. This catalyst had high acid density as characterized by scanning electron microscope (SEM, energy-dispersive x-ray spectrometry (EDX and Brunauer, Emmett, and Teller (BET method analyses. It was further used to catalyze the esterification of oleic acid and one-step conversion of non-pretreated Jatropha oil to biodiesel. The effects of catalyst loading, reaction temperature and oil-to-methanol molar ratio, on the catalytic activity of the esterification were investigated. Results The highest catalytic activity was achieved with a 96.1% esterification rate, and the catalyst can be reused three times with little deactivation under optimized conditions. Biodiesel production from Jatropha oil was studied under such conditions. It was found that 96.3% biodiesel yield from non-pretreated Jatropha oil with high-acid value (12.7 mg KOH/g could be achieved. Conclusions The catalyst can be easily separated for reuse. This single-step process could be a potential route for biodiesel production from high-acid value oil by simplifying the procedure and reducing costs.

  4. A novel mesoporous sulfated zirconium solid acid catalyst for Friedel-Crafts benzylation reaction

    Miao, Zhichao; Zhou, Jin; Zhao, Jinping; Liu, Dandan; Bi, Xu; Chou, Lingjun; Zhuo, Shuping


    In this paper, a novel mesoporous sulfated zirconium (M-ZrO2/SO42-) has been gotten by one-pot evaporation-induced self-assembly (one-pot EISA) strategy. The SXRD, N2-physisorption and TEM characterization techniques indicated that M-ZrO2/SO42- possessed distinct mesostructure with big specific surface area (133.5 m2 g-1), large pore volume (0.18 cm3 g-1) and narrow pore size distribution (4.90 nm). Moreover, the existing states and the influence in mesostructure of introduced S species were detailedly investigated by the XRD, N2-physisorption, TEM, TG-DSC, FT-IR and XPS techniques and the results showed that the S species, which existed as the type of SO42-, improved the textural properties of prepared materials. In addition, the NH3-TPD and IR spectra of adsorbed pyridine indicated the existence of strong Brønsted and Lewis acid sites in M-ZrO2/SO42- even evacuated at 400 °C. Furthermore, the M-ZrO2/SO42- was used as a promise solid acid catalyst and displayed excellent catalytic performance and reusability in Friedel-Crafts benzylation reaction.

  5. A bifunctional palladium-acid solid catalyst performs the direct synthesis of cyclohexylanilines and dicyclohexylamines from nitrobenzenes

    Rubio Marqués, Paula; Leyva Perez, Antonio; Corma Canós, Avelino


    Nitroderivatives are transformed to cyclohexylanilines at room temperature in good yields and selectivity via a hydrogenation-amine coupling cascade reaction using Pd nanoparticles on carbon as a catalyst and a Bronsted acid. Consolider-Ingenio MULTICAT subprograma de Apoyo a Centros y Universidades de Excelencia Severo Ochoa SEV 2012 0267 MICINN MAT2009-00889 FPU contract ITQ Rubio Marqués, P.; Leyva Perez, A.; Corma Canós, A. (2013). A bifunctional palladium-acid solid ca...

  6. Preparation of diglyceride with resin as catalyst%树脂催化酯化制备甘二酯的研究

    肖新生; 杨天奎


    Soybean oil fatty acid was esterified with glycerol to obtain diglyceride with strong acid cation exchange resin 732 as catalyst. The optimal conditions for synthesizing diglyceride were as follows; reaction temperature 100℃ , dosage of resin 10% ( based on the mass of fatty acid) , mass ratio of fatty acid to glycerol 5:1, reaction time 2 h. Under these conditions,the content of diglyceride in the reaction product was over 45% , and it could achieve 74% by molecular distillation for once. The contents of diglyceride obtained by soybean oil fatty acids with different contents of saturated fatty acids unchanged basically.%采用732型强酸性阳离子交换树脂作为催化剂,以甘油与大豆油脂肪酸为原料合成甘二酯,其最佳合成条件为:反应温度100℃,树脂用量为脂肪酸质量的10%,底物质量比(脂肪酸与甘油质量比)5∶1,反应时间2h.在此条件下得到反应产物中甘二酯的含量可达45%以上,经分子蒸馏一次提纯后,甘二酯含量可达74%.不同饱和脂肪酸含量的大豆油脂肪酸制得的甘二酯含量基本不变.

  7. Zirconium phosphate nanoparticles as a remarkable solid acid catalyst for selective solvent-free alkylation of phenol

    Abdol R. Hajipour; Hirbod Karimi


    A facile synthesis of α-zirconium phosphate (ZP) nanoparticles as an effective, eco-friendly, and recyclable solid acid catalyst is reported. Polyvinylpyrrolidone (PVP) and polyvinyl alcohol (PVA) were used as organic matrix as dispersing agents and served as a template for the nanoparticles. Hydrogen bonds between ZP and PVA or PVP, along the polymer chains, appear to play an im-portant role for improving the dispersion of in situ formed ZP. Following calcination of PVA/ZP or PVP/ZP, pure hexagonal ZP nanoparticles were obtained. The catalysts were characterized by ni-trogen sorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, Fouri-er transform infrared spectroscopy (FTIR), scanning electron microscopy, and transmission elec-tron microscopy. Pyridine-FTIR and temperature-programmed desorption of NH3 suggest the presence of Brönsted acid sites. The acidic properties of the catalyst were studied in Friedel-Crafts alkylation of phenol by tert-butanol, producing 2-tert-butylphenol, 4-tert-butylphenol, and 2,4-di-tert-butylphenol. The alkylation reaction was performed in the presence of catalysts P2O5/Al2O3, P2O5/SiO2, α-ZrP (prepared in the absence of the polymers), and various ionic liquids. The use of the hexagonal ZP nanoparticle catalyst afforded an excellent phenol conversion (86%) and selectivity towards 4-tert-butylphenol (83%) under optimized reaction conditions. The catalyst was easily recovered from the reaction mixture, regenerated, and reused at least four times without significant loss in the catalytic activity.

  8. Chromium speciation by solid phase extraction on Dowex M 4195 chelating resin and determination by atomic absorption spectrometry

    Saygi, Kadriye Ozlem; Tuzen, Mustafa [Gaziosmanpasa University, Faculty of Science and Arts, Chemistry Department, 60250 Tokat (Turkey); Soylak, Mustafa [Erciyes University, Faculty of Science and Arts, Chemistry Department, 38039 Kayseri (Turkey)], E-mail:; Elci, Latif [Pamukkale University, Faculty of Science and Arts, Chemistry Department, 20020 Denizli (Turkey)


    A solid phase extraction procedure has been established for chromium speciation in natural water samples prior to determination by atomic absorption spectrometry. The procedure is based on the solid phase extraction of the Cr(VI)- Dowex M 4195 chelating resin. After oxidation of Cr(III) to Cr(VI) by using H{sub 2}O{sub 2}, the presented method was applied to the determination of the total chromium. The level of Cr(III) is calculated by difference of total chromium and Cr(VI) levels. The procedure was optimized for some analytical parameters including pH, eluent type, flow rates of sample and eluent, matrix effects, etc. The presented method was applied for the speciation of chromium in natural water samples with satisfactory results (recoveries >95%, RSDs <10%). In the determinations of chromium species, flame atomic absorption spectrometer was used. The results were checked by using NIST SRM 2711 Montana soil and GBW 07603 Bush branched and leaves.

  9. Evaluation of Resin Dissolution Using an Advanced Oxidation Process - 13241

    Goulart de Araujo, Leandro; Vicente de Padua Ferreira, Rafael; Takehiro Marumo, Julio [Nuclear and Energy Research Institute, Av. Lineu Prestes, 2242., Sao Paulo, SP. (Brazil); Passos Piveli, Roque; Campos, Fabio [The Polytechnic School of the University of Sao Paulo, Av. Prof. Almeida Prado, 83, trav.2. Sao Paulo, SP (Brazil)


    The ion-exchange resin is widely used in nuclear reactors, in cooling water purification and removing radioactive elements. Because of the long periods of time inside the reactor system, the resin becomes radioactive. When the useful life of them is over, its re-utilization becomes inappropriate, and for this reason, the resin is considered radioactive waste. The most common method of treatment is the immobilization of spent ion exchange resin in cement in order to form a solid monolithic matrix, which reduces the radionuclides release into the environment. However, the characteristic of contraction and expansion of the resin limits its incorporation in 10%, resulting in high cost in its direct immobilization. Therefore, it is recommended the utilization of a pre-treatment, capable of reducing the volume and degrading the resin, which would increase the load capacity in the immobilization. This work aims to develop a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Advanced Oxidative Process (AOP) with Fenton's reagent (hydrogen peroxide and ferrous sulphate as catalyst). The resin evaluated was a mixture of cationic (IR 120P) and anionic (IRA 410) resins. The reactions were conducted by varying the concentration of the catalyst (25, 50, 100 e 150 mM) and the volume of the hydrogen peroxide, at three different temperatures, 50, 60 and 70 deg. C. The time of reaction was three hours. Total organic carbon content was determined periodically in order to evaluate the degradation as a function of time. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%, using up to 330 mL of hydrogen peroxide. The most effective temperature was about 60 deg. C, because of the decomposition of hydrogen peroxide in higher temperatures. TOC content was influenced by the concentration of the catalyst, interfering in the beginning of the

  10. Synthesis and Characterization of Tin (IV Tungstate Nanoparticles – A Solid Acid Catalyst

    Manoj Sadanandan


    Full Text Available Tin (IV tungstate, a tetravalent metal acid salt was synthesized in the nanoform by chemical coprecipitation method using EDTA as capping agent. The material was found to be stable in mineral acids, bases and organic solvents except  in HF and aquaregia. The material was characterized using EDS, TG/DTA, FTIR, XRD, SEM, HRTEM and BET surface area measurement. The molecular formula of the compound is 2SnO2 3WO3.5H2O determined from elemental analysis using TG/DTA. Surface morphology and particle size were obtained using SEM and HRTEM. The surface area was found to be 205-225m2/g. The Na+ exchange capacity found to be 3.8 meq/g, indicates the presence of surface hydroxyl group and hence the presence of Bronsted acid sites. The catalytic activity of the material was tested by using esterification and oxidation as model reactions. For the esterification of different alcohols, the percentage yield was found to be high for n-alcohol compared to isomeric alcohols. Oxidation of benzyl alcohol gives benzaldehyde and benzoic acid as the only products. Copyright © 2012 by BCREC UNDIP. All rights reservedReceived: 12nd June 2012, Revised: 23rd July 2012, Accepted: 29th July 2012[How to Cite: S. Manoj, R. Beena, (2012. Synthesis and Characterization of tin(IV Tungstate Nanoparticles – A Solid Acid Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 7 (2: 105-111. doi:10.9767/bcrec.7.2.3622.105-111] [How to Link / DOI: ] | View in 

  11. Recent progress in the development of solid catalysts for biomass conversion into high value-added chemicals

    Hara, Michikazu; Nakajima, Kiyotaka; Kamata, Keigo


    In recent decades, the substitution of non-renewable fossil resources by renewable biomass as a sustainable feedstock has been extensively investigated for the manufacture of high value-added products such as biofuels, commodity chemicals, and new bio-based materials such as bioplastics. Numerous solid catalyst systems for the effective conversion of biomass feedstocks into value-added chemicals and fuels have been developed. Solid catalysts are classified into four main groups with respect to their structures and substrate activation properties: (a) micro- and mesoporous materials, (b) metal oxides, (c) supported metal catalysts, and (d) sulfonated polymers. This review article focuses on the activation of substrates and/or reagents on the basis of groups (a)–(d), and the corresponding reaction mechanisms. In addition, recent progress in chemocatalytic processes for the production of five industrially important products (5-hydroxymethylfurfural, lactic acid, glyceraldehyde, 1,3-dihydroxyacetone, and furan-2,5-dicarboxylic acid) as bio-based plastic monomers and their intermediates is comprehensively summarized. PMID:27877800

  12. Recent progress in the development of solid catalysts for biomass conversion into high value-added chemicals

    Hara, Michikazu; Nakajima, Kiyotaka; Kamata, Keigo


    In recent decades, the substitution of non-renewable fossil resources by renewable biomass as a sustainable feedstock has been extensively investigated for the manufacture of high value-added products such as biofuels, commodity chemicals, and new bio-based materials such as bioplastics. Numerous solid catalyst systems for the effective conversion of biomass feedstocks into value-added chemicals and fuels have been developed. Solid catalysts are classified into four main groups with respect to their structures and substrate activation properties: (a) micro- and mesoporous materials, (b) metal oxides, (c) supported metal catalysts, and (d) sulfonated polymers. This review article focuses on the activation of substrates and/or reagents on the basis of groups (a)-(d), and the corresponding reaction mechanisms. In addition, recent progress in chemocatalytic processes for the production of five industrially important products (5-hydroxymethylfurfural, lactic acid, glyceraldehyde, 1,3-dihydroxyacetone, and furan-2,5-dicarboxylic acid) as bio-based plastic monomers and their intermediates is comprehensively summarized.

  13. Structural and catalytic properties of a novel vanadium containing solid core mesoporous silica shell catalysts for gas phase oxidation reaction

    N Venkatathri; Vijayamohanan K Pillai; A Rajini; M Nooka Raju; I A K Reddy


    A novel vanadium containing solid core mesoporous silica shell catalyst was synthesized with different Si/V ratios by sol-gel method under neutral conditions. The synthesized materials were characterized by various techniques and gas phase diphenyl methane oxidation reaction. The mesoporosity combined with microporosity are formed by incorporation of octadecyltrichloro silane and triethylamine in the catalyst and it was found out from E-DAX and BET—surface area analysis. The material was found to be nanocrystalline. Vanadium is present as V4+ species in as-synthesized samples and convert to V5+ on calcination. Most of the vanadium is present in tetrahedral or square pyramidal environment. Incorporation of vanadium in silica framework was confirmed by 29Si MAS NMR analysis. Among the various vanadium containing solid core mesoporous silica shell catalysts, the Si/V =100 ratio exhibited maximum efficiency towards diphenyl methane to benzophenone gas phase reaction. The optimum condition required for maximum conversion and selectivity was found out from the catalytic studies.

  14. Hydrolysis of Cellulose by a Mesoporous Carbon-Fe2(SO4)3/γ-Fe2O3 Nanoparticle-Based Solid Acid Catalyst

    Yamaguchi, Daizo; Watanabe, Koki; Fukumi, Shinya


    Carbon-based solid acid catalysts have shown significant potential in a wide range of applications, and they have been successfully synthesized using simple processes. Magnetically separable mesoporous carbon composites also have enormous potential, especially in separation and adsorption technology. However, existing techniques have been unable to produce a magnetically separable mesoporous solid acid catalyst because no suitable precursors have been identified. Herein we describe a magnetically separable, mesoporous solid acid catalyst synthesized from a newly developed mesoporous carbon-γ-Fe2O3 nanoparticle composite. This material exhibits an equivalent acid density and catalytic activity in the hydrolysis of microcrystalline cellulose, to that of the cellulose-derived conventional catalyst. Since it is magnetically separable, this material can be readily recovered and reused, potentially reducing the environmental impact of industrial processes to which it is applied.

  15. Solid-liquid extraction of Gd(Ⅲ) and separation possibilities of rare earths from phosphoric acid solutions using Tulsion CH-93 and Tulsion CH-90 resins

    S.Radhika; V.Nagaraju; B.Nagaphani Kumar; M.Lakshmi Kantam; B.Ramachandra Reddy


    Solid-liquid extraction of gadolinium was investigated from phosphoric acid medium using commercial amino phosphonic acid resin,Tulsion CH-93.The experimental conditions studied included equilibration time,acid concentration,mass of the resin,metal concentration,loading and elution.The percent extraction of Gd(Ⅲ) was studied as a function of phosphoric acid (0.05-3 mol/L) using Tulsion CH-93 resin.The corresponding lgD vs.equilibrium pH plot gave straight line with a slope of 1.8.The percent extraction decreased with acid concentration increasing,conforming ion exchange mechanism.Under observed experimental conditions the loading capacity of Tulsion CH-93 for gadolinium was 10.6 mg/g.Among several eluants screened,the quantitative elution of Gd(Ⅲ) from loaded Tulsion CH-93 was obtained with ammonium oxalate (0.15 mol/L).The extraction behavior of commonly associated metals with gadolinium was studied as a function of phosphoric acid concentration.Tulsion CH-93 resin showed selective extraction towards heavy rare earths (Lu and Yb) which could be separated from other rare earths at 3 mol/L H3PO4,similar to wet phosphoric acid (3-5 mol/L).On the other hand Gd(Ⅲ) and other rare earths were studied with chelating resin Tulsion CH-90.Light rare earths were highly extracted and these could be separated from heavy rare earths and Gd.

  16. Effect of solid particle loading on nucleophilic addition of epoxy-resin to isophorone diisocyanate

    Wei Zhang; Richard S.Blackburn; Abbas A.Dehghani-Sanij


    In the preparation of surface coatings made of conductive composites consisting of conductive particulate fillers in a soft matrix, cracks will develop with increase of the particulate loading, which is believed to be related to the nucleophilic addition reaction between glycidyl end-capped poly (bisphenol A-co-epichlorohydrin) and isophorone diisocyanate molecules. This curing reaction is responsible for the generation of cross-linking network throughout the coatings. The influence of solid particle loading on the chemical reaction may be described as a volume-excluded effect, that is, the high solid particle loading will occupy the space between the functional groups thus preventing the chemical reaction to take place. As a direct consequence, the cross-linking network cannot develop properly due to the insufficiency of curing reaction. This will lead to the generation of cracks, as was supported by FT-IR analysis in this work.

  17. 负载型钌-钇双金属催化剂催化萜烯树脂加氢反应研究%Study on the hydrogenation of terpene resin with supported ruthenium-yttrium bimetallic catalysts

    郑惠榕; 林嘉渭; 郑国才; 林棋


    采用浸渍法制备了负载型Ru-Y/TiO2催化剂,并考察了其在萜烯树脂加氢反应中的催化性能。结果表明,负载型Ru-Y/TiO2催化剂对萜烯树脂加氢反应具有较高的催化活性,在150℃,氢气压力4 MPa,反应时间6 h,制得了无色或浅色萜烯树脂,加氢反应前、后萜烯树脂的色差可达82%以上,且催化剂稳定性较好,循环使用5次后,其催化萜烯树脂加氢反应前后的色差仍高于75%。合成的无色或浅色萜烯树脂具有无毒、稳定和抗老化等特性,可广泛应用于塑料、油墨、涂料、黏合剂、电子产品、食品加工和医药材料等领域。%The supported Ru-Y/TiO2 catalysts was prepared by impregnation and characterized by XRD and SEM. The catalytic ac-tivity on the hydrogenation of terpene resin to colorless terpene resin was explored. The results indicated that,the hydrogenation of terpene resin exhibited higher activity under the optimal reaction conditions as:terpene resin 1. 000 g,2. 5%Ru-2. 5%Y/TiO2 0. 040 g,n-hexane 2 mL,150℃,4 MPa,6 h. Color-difference of terpene resin was up to 82. 7%before and after hydrogenation. Mo-reover,the products were conveniently separated from the catalyst by simple decantation, and the catalyst could be reused five times,the color-difference of terpene resin is higher 75%before and after hydrogenation. The decolorized terpene resins might be used as plastics,printing inks,paintings,adhesive,electronic products,food processing and health goods because it was innocuous, stable and aging-resistant.

  18. Kinetics Studies on Esterification Reaction of Acetic acid with Iso-amyl Alcohol over Ion Exchange Resin as Catalysts

    Bhaskar D. Kulkarni


    Full Text Available The low molecular weight organic esters have pleasing smell and are found in applications in the food industry for synthetic essence and perfume. Esterification reactions are ubiquitous reactions especially in pharmaceutical, perfumery and polymer industries, wherein; both heterogeneous and homogeneous catalysts have been extensively used. Iso-amyl acetate (or Iso-pentyl acetate is often called as banana oil, since it has the recognizable odor of this fruit. Iso-amyl acetate is synthesized by esterification of acetic acid with iso-amyl alcohol. (Eq.1. Since the equilibrium does not help the formation of the ester, it must be shifted to the right, in favor of the product, by using a surplus of one of the starting materials. Iso-amyl acetate is a kind of flavor reagent with fruit taste. The use of H2SO4 often originates the problems such as corrosion for equipments and pollution for environment.

  19. Vapor-phase Beckmann rearrangement of cyclohexanone oxime over solid acid catalysts

    Murakami, Y.; Saeki, Y.; Ito, K.


    Of various catalysts tested for the conversion of cyclohexanone oxime to epsilon-caprolactam, best results were obtained with the catalyst having the strongest acid sites, silica-alumina, which gave 60% selectivity at 100% conversion at 330/sup 0/C, 0.505 g catalyst hr/mole, and 0.0563 atm cyclohexanone oxime partial pressure. A decline in activity without loss of selectivity was observed for all catalysts as carbonaceous deposits formed with time on stream (e.g., the caprolactam yield on silica-alumina declined to 90% after 120 min and to 35% after 270 min). Pulse reactor tests with silica-alumina with and without preadsorbed caprolactam showed that cyclohexanone oxime adsorbed even more strongly than the strongly adsorbed caprolactam. The mechanism is discussed. Graphs and 21 references.

  20. Quantitative characterization of solid epoxy resins using comprehensive two dimensional liquid chromatography coupled with electrospray ionization-time of flight mass spectrometry.

    Julka, Samir; Cortes, Hernan; Harfmann, Robert; Bell, Bruce; Schweizer-Theobaldt, Andreas; Pursch, Matthias; Mondello, Luigi; Maynard, Shawn; West, David


    A comprehensive multidimensional liquid chromatography system coupled to Electrospray Ionization-Mass Spectrometry (LCxLC-ESI-MS) was developed for detailed characterization and quantitation of solid epoxy resin components. The two orthogonal modes of separation selected were size exclusion chromatography (SEC) in the first dimension and liquid chromatography at critical conditions (LCCC) in the second dimension. Different components present in the solid epoxy resins were separated and quantitated for the first time based on the functional groups and molecular weight heterogeneity. Coupling LCxLC separations with mass spectrometry enabled the identification of components resolved in the two-dimensional space. Several different functional group families of compounds were separated and identified, including epoxy-epoxy and epoxy-alpha-glycol functional oligomers, and their individual molecular weight ranges were determined. Repeatability obtained ranged from 0.5% for the main product to 21% for oligomers at the 0.4% concentration level.

  1. Synthesis of High Solid Polyester Resin%高固体分聚酯树脂的合成



    A high solid polyester resin was synthesized by polybasic acid and polyols using melting condensation reaction. The synthetic products were characterized by Fourier transform infrared spectrometry ( FTIR ) and gel permeation chromatography ( GPC ). The effects of monomers, the molar ratio of alcohol and acid, reaction temperature, reaction time and charging method on the performance of the synthetic products were researched.%以多元酸和多元醇为反应单体,采用熔融缩聚的方法合成了高固体分聚酯树脂。对合成产物进行了傅里叶变换红外光谱(FTIR)和凝胶渗透色谱(GPC)等表征。研究了反应单体、n醇/n酸、反应温度、反应时间、加料方法对合成产物性能的影响。

  2. Mechanistic studies of the vapor-phase Beckmann rearrangement on solid catalysts by in situ solid-state NMR spectroscopy

    Marthala, Venkata Ramana Reddy


    Epsilon-Caprolactam, the main product of the Beckmann rearrangement of cyclohexanone oxime, is an intermediate in the manufacture of nylon-6. Currently, most of the industrial plants produce epsilon-caprolactam by the Beckmann rearrangement of cyclohexanone oxime using sulphuric acid or oleum as a homogeneous catalyst. This process has two main disadvantages: (i) The production of uneconomical by-product, such as ammonium sulphate, and (ii) the environmentally unfriendly corrosive reaction me...

  3. Efficient hydrolysis of cellulose over a magnetic lignin-derived solid acid catalyst in 1-butyl-3-methylimidazolium chloride

    Hu, Lei; Wu, Zhen; Xu, Jiaxing; Zhou, Shouyong; Tang, Guodong [Huaiyin Normal University, Huaian (China)


    A green and efficient strategy for the hydrolysis of cellulose was developed by using a magnetic lignin-derived solid acid catalyst (MLC-SO{sub 3}H) in the presence of ionic liquid 1-butyl-3-methylimidazolium chloride ([BMIM]Cl). The results indicated that reaction temperature, reaction time, catalyst loading and water content have a big influence on the yield of total reducing sugars (TRS). By optimizing these reaction parameters, 69.3% TRS yield was observed at 140 .deg. C for 150 min with the addition of 40 wt% MLC-SO{sub 3}H and 1 wt% water. More importantly, MLC-SO{sub 3}H could be easily separated from the reaction mixture with an external magnet and could be repeatedly used five times without an obvious loss of catalytic activity, demonstrating that it possessed excellent recyclability. Furthermore, a plausible mechanism involving three consecutive processes of dissolution, adsorption and catalysis for the hydrolysis of cellulose in [BMIM]Cl over a catalyst of MLC-SO{sub 3}H was also proposed.

  4. Preparation, characterization and catalytic properties of S2O82-/ZrOe-CeO2 solid superacid catalyst

    FAN Guodong; SHEN Mao; ZHANG Zhao; JIA Farui


    A novel solid superacid catalyst S2O82-/ZrO2-CeO2 was prepared by a coprecipitation method and characterized by means of XRD, FTIR, BET, TEM and DSC/TG analysis methods. The results indicated that incorporation of appropriate amounts of Ce into the catalyst was beneficial to the formation of sole tetragonal ZrO2 and effectively prevented from the formation of monoclinic ZrO2, and restrained the loss of sulfated species. XRD revealed the presence of tetragonal Ceo0.16Zr0.84O2phase in the case of S2O82-/ZrO2-CeO2 calcined above 500 ℃. Catalytic activities of S2O82-/ZrO2-CEO2 for the estefification of lactic acid with n-butanol was studied. The results showed that the optimttrn conditions were as follows: calcination temperature of the catalyst 600 ℃, n(lactic acid):n(n-butyl alcohol)=1.0:3.0, w(S2O82-/ZrO2-CEO2)=12.0%, reaction temperature 145 ℃, and reaction time 2 h. The esterification efficiency of lactic acid was about 96.6%.

  5. Solid frustrated-Lewis-pair catalysts constructed by regulations on surface defects of porous nanorods of CeO2

    Zhang, Sai; Huang, Zheng-Qing; Ma, Yuanyuan; Gao, Wei; Li, Jing; Cao, Fangxian; Li, Lin; Chang, Chun-Ran; Qu, Yongquan


    Identification on catalytic sites of heterogeneous catalysts at atomic level is important to understand catalytic mechanism. Surface engineering on defects of metal oxides can construct new active sites and regulate catalytic activity and selectivity. Here we outline the strategy by controlling surface defects of nanoceria to create the solid frustrated Lewis pair (FLP) metal oxide for efficient hydrogenation of alkenes and alkynes. Porous nanorods of ceria (PN-CeO2) with a high concentration of surface defects construct new Lewis acidic sites by two adjacent surface Ce3+. The neighbouring surface lattice oxygen as Lewis base and constructed Lewis acid create solid FLP site due to the rigid lattice of ceria, which can easily dissociate H-H bond with low activation energy of 0.17 eV.

  6. Biodiesel production in a membrane reactor using MCM-41 supported solid acid catalyst.

    Xu, Wei; Gao, Lijing; Wang, Songcheng; Xiao, Guomin


    Production of biodiesel from the transesterification between soybean oil and methanol was conducted in this study by a membrane reactor, in which ceramic membrane was packed with MCM-41 supported p-toluenesulfonic acid (PTSA). Box-Behnken design and response surface methodology (RSM) were used to investigate the effects of reaction temperature, catalyst amount and circulation velocity on the yield of biodiesel. A reduced cubic model was developed to navigate the design space. Reaction temperature was found to have most significant effect on the biodiesel yield while the interaction of catalyst amount and circulation velocity have minor effect on it. 80°C of reaction temperature, 0.27 g/cm(3) of catalyst amount and 4.15 mL/min of circulation velocity were proved to be the optimum conditions to achieve the highest biodiesel yield. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Green and efficient synthesis of aryl/alkylbis(indolyl)methanes using Expanded Perlite-PPA as a heterogeneous solid acid catalyst in aqueous media



    Expanded Perlite-Polyphosphoric acid (EP-PPA) as a novel, efficient, recyclable and eco-benign heterogeneous catalyst has been applied for the green and rapid synthesis of aryl/alkylbis(indolyl)methanes, in water, in good to excellent yields. The catalyst was characterized by XRF, FT-IR, TGA/DTG, ICP-OES, SEMEDX and pH analysis. Importantly, the newly synthesized heterogeneous solid acid catalyst can be recovered and reused six times without any significant loss in its catalytic potential. The remarkable features of thepresent methodology are high conversions, shorter reaction times, cleaner reaction profiles and simple work-up procedures.

  8. Poly(N-4-vinylbenzyl-1,4,7-triazacyclononane Copper Complex Grafted Solid Catalyst for Oxidative Polymerization of 2,6-Dimethylphenol

    Kei Saito


    Full Text Available A new solid phase catalyst, poly(N-4-vinylbenzyl-1,4,7-triazacyclononane copper(I complex, grafted onto polystyrene particles, has been employed for the oxidative polymerization of 2,6-dimethylphenol using an aqueous biphasic (water/toluene solvent system. The solid catalyst was synthesized by first grafting N-(4-vinylbenzyl-1,4,7-triaza-cyclononane onto polystyrene particles using a radical mediated polymerization method and next by creating the polymer-metal complex of copper-triazacyclononane with these modified particles. Poly(2,6-dimethyl-1,4-phenylene oxide was successfully obtained from the polymerization of 2,6-dimethylphenol using this new metal-organic solid phase catalyst.

  9. Poly(N-4-vinylbenzyl-1,4,7-triazacyclononane) Copper Complex Grafted Solid Catalyst for Oxidative Polymerization of 2,6-Dimethylphenol.

    Saito, Kei; Miyamoto, Koji; Nanayakkara, Sepa; Ihara, Hirotaka; Hearn, Milton T W


    A new solid phase catalyst, poly(N-4-vinylbenzyl-1,4,7-triazacyclononane) copper(I) complex, grafted onto polystyrene particles, has been employed for the oxidative polymerization of 2,6-dimethylphenol using an aqueous biphasic (water/toluene) solvent system. The solid catalyst was synthesized by first grafting N-(4-vinylbenzyl)-1,4,7-triaza-cyclononane onto polystyrene particles using a radical mediated polymerization method and next by creating the polymer-metal complex of copper-triazacyclononane with these modified particles. Poly(2,6-dimethyl-1,4-phenylene oxide) was successfully obtained from the polymerization of 2,6-dimethylphenol using this new metal-organic solid phase catalyst.

  10. Preparation of Mg-doped Ce-Zr Solid Catalysts and Their Catalytic ...


    Addition of MgO to the Ce-Zr mixed metal oxides affected both particle size and catalytic activity. KEYWORDS ... effect on vascular smooth muscle.6 2,4-TZD has an active methy- ... catalytic properties and for a given reaction the activity and selectivity of the ... heterogeneous catalysts for fine chemical synthesis under green.

  11. Calcium Oxide Supported on Monoclinic Zirconia as a Highly Active Solid Base Catalyst

    Frey, A.M.; Haasterecht, van T.; Jong, de K.P.; Bitter, J.H.


    Calcium oxide supported on ZrO2 is a highly active catalyst for base-catalyzed reactions such as aldol-type reactions and transesterification reactions. The role of key parameters during preparation, that is, impregnation versus precipitation, heat treatment, and metal oxide loading on the basicity

  12. Glycerol Esters from Real Waste Cooking Oil Using a Robust Solid Acid Catalyst

    Venkatesh, S.; van Zwol, P.; Dimian, A.C.; Gitis, V.; Rothenberg, G.


    Notwithstanding the food-​for-​fuel debate, turning waste cooking oil and fat (WCO) into a valuable product is a classic example of green chem. We demonstrate that sulfated zirconia and lanthanum-​supported sulfated zirconia are good catalysts for the esterification of WCO free fatty acids (FFAs)

  13. Study of the reaction between polyethylene glycol and epoxy resins using N,N-dimethylbenzylamine as catalyst;Estudo da reacao entre polietileno glicol e resinas epoxi usando N,N-dimetilbenzilamina como catalisador

    Zacharuk, Mario; Coelho, Luiz A.F.; Pezzin, Sergio H., E-mail: pezzin@joinville.udesc.b [Universidade do Estado de Santa Catarina (UDESC), Joinville (Brazil). Centro de Ciencias Tecnologicas; Becker, Daniela [Sociedade Educacional de Santa Catarina (SOCIESC), Joinville (Brazil). Inst. Superior Tupy


    In this work the use of N,N-dimethylbenzylamine as a catalyst of the reaction of polyethylene glycol (PEG) and epoxy resin (DGEBA) was studied. The reaction products were evaluated by infra-red spectroscopy (FTIR), nuclear magnetic resonance spectroscopy (NMR) and viscosity measurements. Samples cured with a polyamine-based hardener were also submitted to tensile tests and differential scanning calorimetry (DSC). The results of the viscosity analyses, FTIR and RMN ({sup 1}H) had confirmed the occurrence of the reaction between DGEBA epoxy groups and PEG hydroxyl groups in the presence of N, N-dimethylbenzylamine as catalyst, at 100 deg C. DSC analyses and tensile tests of cured systems showed that the reaction of DGEBA with PEG leads to a reduction of the Tg, generating a more flexible material. (author)

  14. Chemically modified polymeric resins for solid-phase extraction and group separation prior to analysis by liquid or gas chromatography

    Schmidt, L.W.


    Polystyrene divinylbenzene was modified by acetyl, sulfonic acid, and quaternary ammonium groups. A resin functionalized with an acetyl group was impregnated in a PTFE membrane and used to extract and concentrate phenolic compounds from aqueous samples. The acetyl group created a surface easily wetted, making it an efficient adsorbent for polar compounds in water. The membrane stabilized the resin bed. Partially sulfonated high surface area resins are used to extract and group separate an aqueous mixture of neutral and basic organics; the bases are adsorbed electrostatically to the sulfonic acid groups, while the neutraons are adsorbed hydrophobically. A two-step elution is then used to separate the two fractions. A partially functionalized anion exchange resin is used to separate organic acids and phenols from neutrals in a similar way. Carboxylic acids are analyzed by HPLC and phenols by GC.

  15. Evaluation of the resin oxidation process using Fenton's reagent

    Araujo, Leandro G.; Goes, Marcos M.; Marumo, Julio T., E-mail: [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)


    The ion exchange resin is considered radioactive waste after its final useful life in nuclear reactors. Usually, this type of waste is treated with the immobilization in cement Portland, in order to form a solid monolithic matrix, reducing the possibility of radionuclides release in to environment. Because of the characteristic of expansion and contraction of the resins in presence of water, its incorporation in the common Portland cement is limited in 10% in direct immobilization, causing high costs in the final product. A pre-treatment would be able to reduce the volume, degrading the resins and increasing the load capacity of this material. This paper is about a method of degradation of ion spent resins from the nuclear research reactor of Nuclear and Energy Research Institute (IPEN/CNEN-SP), Brazil, using the Fenton's reagent. The resin evaluated was a mixture of cationic and anionic resins. The reactions were conducted by varying the concentration of the catalyst (25 to 80 mM), with and without external heat. The time of reaction was two hours. The concentration of 50 mM of catalyst was the most effective in degrading approximately 99%. The resin degradation was confirmed by the presence of CaCO{sub 3} as a white precipitate resulting from the reaction between the Ca(OH){sub 2} and the CO{sub 2} from the resin degradation. It was possible to degrade the resins without external heating. The calcium carbonates showed no correlation with the residual resin mass. (author)

  16. 一种新的光固化树脂齐聚物合成用催化剂%New Kind of Catalyst Used for Preparing Oligomer for Light-Curable Resin

    张瑾璐; 曹瑞军; 王素琴


    The shortcomings of conventional catalyst are bulky and low activity,that lead to long reaction time, large relic volume and high viscosity. A new kind of catalyst-triethyl-allyl ammonia chloride is designed and developed that can be used for preparing a proper oligomer for SL light-curable resin. Owing to unsaturated double bond of the new catalyst, it can participate the reaction when UV solidify,at the same time,the relic volume is decreased. The reaction can be finished at lower temperature(80~90 ℃) and shorter time(2 h) by the high activity of the new catalyst, and the viscosity of resin is also decreased.%针对常规催化剂体积大、活性低、反应时间(t)长、粘度及残余量大等缺点,设计合成了一种新的催化剂——三乙基烯丙基氯化胺,以用于SL(StereoLithography)法光固化树脂专用齐聚物的制备.因为新的催化剂带有不饱和双键,所以在紫外光固化时可参与聚合,残余量少,并且其催化活性高,可在较低温度(80~90 ℃)及较短时间(2 h)内完成反应,因此降低了体系的粘度.

  17. Selective conversion of cotton cellulose to glucose and 5-hydroxymethyl furfural with SO4(2-)/MxOy solid superacid catalyst.

    Yang, Fang; Li, Yang; Zhang, Qian; Sun, Xiaofeng; Fan, Hongxian; Xu, Nian; Li, Gang


    This paper presented a mild hydrothermal process for degradation of cotton cellulose with solid superacid catalyst and selective conversion of cotton cellulose to glucose and 5-hydroxymethyl furfural (HMF). Five kinds of solid superacid catalyst such as SO4(2-)/SnO2, SO4(2-)/TiO2, SO4(2-)/ZrO2, SO4(2-)/Fe2O3 and SO4(2-)/Al2O3 were prepared by impregnation method. The BET surface area of catalyst SO4(2-)/SnO2 was up to 118.8m(2)g(-1) when impregnation was performed with 1molL(-1) H2SO4 of impregnating solution at 550°C calcination temperature for 3h. It made the hydrothermal temperature of cellulose degradation decrease to 190°C successfully and suppressed the side reaction. The NH3-TPD profile of SO4(2-)/SnO2 indicated there was a wide region of stronger acid sites on the catalyst surface. The depolymerization of cotton cellulose obtained 11.0% yield and 22.0% selectivity of HMF and 26.8% yield and 53.4% selectivity of glucose, respectively. The regeneration and reuse of solid superacid catalyst were also discussed in this paper.

  18. Electrochemical catalyst recovery method

    Silva, Laura J.; Bray, Lane A.


    A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

  19. Selective catalytic reduction of NOx with NH3 over a Cu-SSZ-13 catalyst prepared by a solid state ion exchange method

    Wang, Di; Gao, Feng; Peden, Charles HF; Li, Junhui; Kamasamudram, Krishna; Epling, William S.


    A novel solid state method was developed to synthesize Cu-SSZ-13 catalysts with excellent NH3-SCR performance and durable hydrothermal stability. After the solid state ion exchange (SSIE) process, the SSZ framework structure and surface area was maintained. In-situ DRIFTS and NH3-TPD experiments provide evidence that isolated Cu ions were successfully exchanged into the pores, which are the active centers for the NH3-SCR reaction.

  20. Enhanced hydrolysis of bamboo biomass by chitosan based solid acid catalyst with surfactant addition in ionic liquid.

    Si, Wenqing; Li, Yichen; Zheng, Jie; Wei, Shun'an; Wang, Dan


    Surfactants were used for the hydrolysis of bamboo biomass to enhance lignocellulose hydrolysis. Tween 80, polyethylene glycol 4000 (PEG 4000), and sodium dodecyl sulfate (SDS) were tested as surfactants for improving the bamboo hydrolysis with a novel sulfonated cross-linked chitosan solid acid catalyst (SCCAC) in ionic liquid (IL). Compared to the use of only SCCAC in 1-Butyl-3-methylimidazolium chloride ([BMIM]Cl), the surfactants facilitated hydrolysis and improved the yield of total reducing sugar (TRS) under the same conditions. Tween 80 was the most effective surfactant, with a TRS yield of 68.01% achieved at 120°C after 24h. Surfactants broke the lignocellulose structure, promoted lignin removal, and increased positive interactions between cellulose and the catalyst, which were favorable for hydrolysis. This novel surfactant-assisted hydrolysis strategy with SCCAC and IL as the solvent demonstrated a promise for the large-scale transformation of biomass into biofuels and bioproducts. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Bimetallic Nickel/Ruthenium Catalysts Synthesized by Atomic Layer Deposition for Low-Temperature Direct Methanol Solid Oxide Fuel Cells.

    Jeong, Heonjae; Kim, Jun Woo; Park, Joonsuk; An, Jihwan; Lee, Tonghun; Prinz, Fritz B; Shim, Joon Hyung


    Nickel and ruthenium bimetallic catalysts were heterogeneously synthesized via atomic layer deposition (ALD) for use as the anode of direct methanol solid oxide fuel cells (DMSOFCs) operating in a low-temperature range. The presence of highly dispersed ALD Ru islands over a porous Ni mesh was confirmed, and the Ni/ALD Ru anode microstructure was observed. Fuel cell tests were conducted using Ni-only and Ni/ALD Ru anodes with approximately 350 μm thick gadolinium-doped ceria electrolytes and platinum cathodes. The performance of fuel cells was assessed using pure methanol at operating temperatures of 300-400 °C. Micromorphological changes of the anode after cell operation were investigated, and the content of adsorbed carbon on the anode side of the operated samples was measured. The difference in the maximum power density between samples utilizing Ni/ALD Ru and Pt/ALD Ru, the latter being the best catalyst for direct methanol fuel cells, was observed to be less than 7% at 300 °C and 30% at 350 °C. The improved electrochemical activity of the Ni/ALD Ru anode compared to that of the Ni-only anode, along with the reduction of the number of catalytically active sites due to agglomeration of Ni and carbon formation on the Ni surface as compared to Pt, explains this decent performance.

  2. Silica sulfuric acid: a reusable solid catalyst for one pot synthesis of densely substituted pyrrole-fused isocoumarins under solvent-free conditions

    Sudipta Pathak


    Full Text Available A convenient and efficient methodology for the synthesis of densely substituted pyrrole-fused isocoumarins, which employs solid-supported silica sulfuric acid (SSA as catalyst, has been developed. When the mixture of ninhydrin adducts of acetylacetone/ethyl acetoacetate and primary amines was heated on the solid surface of SSA under solvent-free conditions, the pyrrole-fused isocoumarins were formed in good yields. This synthetic method has several advantages such as the employment of solvent-free reaction conditions without the use of any toxic reagents and metal catalysts, the ease of product isolation, the use of a recyclable catalyst, the low cost, the easy availability of the starting materials, and the excellent yields of products.

  3. Synthesis and Characterization of Poly(α-Methylstyrene by Cationic Polymerization Using a New Solid Ecological Catalyst

    Moulkheir Ayat


    Full Text Available The cationic polymerization of α-methylstyrene (AMS is examined at 0°C in bulk and in solution in heterogenous phase using Maghnite-Na as a new solid ecological and efficient catalyst. Maghnite-Na is Algerian Montmorillonite sheet silicate clay, exchanged with sodium. Poly (α-methylstyrene (PAMS have been successfully prepared and characterized by differents techniques, such as, 1H NMR, 13C NMR, IR and DSC. The structural characteristics and thermal properties of the resulting polymers are elucidated. The influences of reaction temperature, initiator/monomer weight ratio and reaction time on the yields and the molecular weights are investigated. A mechanism for the reaction was proposed.

  4. Solid state 13C NMR studies of methane dehydroaromatization reaction on Mo/HZSM-5 and W/HZSM-5 catalysts.

    Yang, Jun; Ma, Ding; Deng, Feng; Luo, Qing; Zhang, Mingjin; Bao, Xinhe; Ye, Chaohui


    Methane dehydroaromatization on Mo/HZSM-5 and W/HZSM-5 catalysts was studied by solid state 13C NMR spectroscopy, both variation of the state of transition metal component and products such as ethane, benzene, ethene adsorbed on or in zeolite were observed after high temperature (900-1000 K) reaction.

  5. Solid phase extraction of chromium(VI) from aqueous solutions by adsorption of its diphenylcarbazide complex on an Amberlite XAD-4 resin column.

    Rajesh, N; Jalan, Rohit Kumar; Hotwany, Pinky


    A method has been developed for the solid phase extraction of chromium(VI) based on the adsorption of its diphenylcarbazide complex on an Amberlite XAD-4 resin column. The influence of acidity, stability of the column, sample volume, flow rate and interfering ions were studied in detail. The adsorbed complex could be eluted using acetone-sulfuric acid mixture and the concentration of chromium was determined using visible spectrophotometry. A detection limit of 6 microg L(-1) could be achieved. A preconcentration factor of 27 could be obtained for 400 mL sample volume. The validity of the method was checked in spiked water samples and electroplating wastewater.

  6. A one-pot method for the selective conversion of hemicellulose from crop waste into C5 sugars and furfural by using solid acid catalysts.

    Sahu, Ramakanta; Dhepe, Paresh Laxmikant


    We present a solid-acid catalyzed one-pot method for the selective conversion of solid hemicellulose without its separation from other lignocellulosic components, such as cellulose and lignin. The reactions were carried out in aqueous and biphasic media to yield xylose, arabinose, and furfural. To overcome the drawbacks posed by mineral acid methods in converting hemicelllulose, we used heterogeneous catalysts that work at neutral pH. In a batch reactor, these heterogeneous catalysts, such as solid acids (zeolites, clays, metal oxides etc.), resulted in >90 % conversion of hemicellulose. It has been shown that the selectivity for the products can be tuned by changing the reaction conditions, for example, a reaction carried out in water at 170 °C for 1 h with HBeta (Si/Al=19) and HUSY (Si/Al=15) catalysts gave yields of 62 and 56 % for xylose and arabinose, respectively. With increased reaction time (6 h) and in presence of only water, HUSY resulted in yields of 30 % xylose + arabinose and 18 % furfural. However, in a biphasic reaction system (water + p-xylene, 170 °C, 6 h) yields of 56 % furfural with 17 % xylose+arabinose could be achieved. It was shown that with the addition of organic solvent the furfural yield could be increased from 18 to 56 %. Under optimized reaction conditions, >90 % carbon balance was observed. The study revealed that catalysts were recyclable with a 20 % drop in activity for each subsequent run. It was observed that temperature, pressure, reaction time, substrate to catalyst ratio, solvent, and so forth had an effect on product formation. The catalysts were characterized by means of X-ray diffraction, temperature-programmed desorption of NH(3), inductively coupled plasma spectroscopy, elemental analysis, and solid-state NMR ((29)Si, (27)Al) spectroscopy techniques.

  7. On-resin N-formylation of peptides: a head-to-head comparison of reagents in solid-phase synthesis of ligands for formyl peptide receptors

    Christensen, Simon Bendt; Hansen, Anna Mette; Franzyk, Henrik


    General conditions for efficient on-resin N-formylation of peptides were identified by screening of a number of reagents comprising aliphatic formates (ethyl formate, 2,2,2-trifluoroethyl formate, and cyanomethyl formate), aromatic esters (phenyl formate and p-nitrophenyl formate), and N-formylim......General conditions for efficient on-resin N-formylation of peptides were identified by screening of a number of reagents comprising aliphatic formates (ethyl formate, 2,2,2-trifluoroethyl formate, and cyanomethyl formate), aromatic esters (phenyl formate and p-nitrophenyl formate), and N......-formylimidazole and in situ activation of formic acid with the coupling reagent 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. Initially, reaction time and influence of solvent were examined for the formylation of a short model peptide. The most efficient reagents were examined further by using different linkers and solid...... supports in the synthesis of an array of longer formyl peptide ligands. For p-nitrophenyl formate and N-formylimidazole, lmost complete conversion was reached within 2 h, albeit longer peptides attached to Tentagel resins via different linkers required an extended reaction time. Overall, the commercially...

  8. Determination of some trace metals by FAAS after solid-phase extraction with amberlite XAD-1180/TAN chelating resin.

    Yilmaz, Vedat; Kartal, Senol


    A new chelating resin was synthesized by immobilizing 1-(2-thiazolylazo)-2-naphthol through the -N=N- group on Amberlite XAD-1180. The resin was used for the preconcentration of Cd(II), Co(II), Cu(II), Mn(II), Ni(II), and Pb(II) ions and their determination by flame atomic absorption spectrometry (FAAS). The influences of some analytical parameters, such as the pH, volume of the sample, flow rates of the sample and eluent, matrix components, amount of the resin, and amount and type of the eluent on the recovery, were investigated. Those metals retained on the resin at pH 8.5 were eluted with 25 mL of 2 mol L(-1) HNO(3). The sorption capacity of the resin was determined, except for Pb(II). The recoveries were found to be ≥95%, and the relative standard-deviation values were ≤4.3%. The detection limits were in the range of 0.1 - 3.6 µg L(-1). For the accuracy of the method, the analysis of a certified reference material was performed. This method was applied to environmental water samples.

  9. Aplicação de resinas sulfônicas como catalisadores em reações de transesterificação de óleos vegetais Evaluation of sulfonic resins as catalysts in transesterification of vegetable oils

    Simone M. de Rezende


    Full Text Available Diferentes suportes poliméricos à base de estireno (S e divinilbenzeno (DVB foram sintetizados e suas morfologias caracterizadas por microscopia óptica e eletrônica de varredura. Foram preparados e caracterizados catalisadores sulfônicos a partir desses suportes e suas atividades catalíticas foram avaliadas na transesterificação de óleo vegetal com metanol. Os resultados obtidos com esses catalisadores foram comparados com os produzidos com uma resina sulfônica comercial. Verificou-se que os catalisadores sintetizados neste trabalho apresentaram desempenhos próximos ao da resina comercial.Different polymer supports based on styrene (S and divinylbenzene (DVB were synthesized and their morphology was characterized by optical and scanning electron microscopy. Sulfonic catalysts were prepared from these supports, characterized and their activities were evaluated in vegetal oil transesterification with methanol and compared with the performance of a commercial sulfonic resin. The synthesized catalysts showed results close to the commercial resin.

  10. 强酸性阳离子交换树脂催化合成乙酰水杨酸的研究%Synthesis of acetylsalicylic acid using strong-acidic cation-exchange resin as catalyst

    赵志刚; 谢志融; 陈靠山


    目的:探讨001×7强酸性阳离子交换树脂催化合成乙酰水杨酸的方法和最佳工艺.方法:通过正交试验探讨了乙酸酐与水杨酸的摩尔比、反应时间、催化剂用量和反应温度对乙酰水杨酸产率的影响,并探讨催化剂的催化能力与使用次数的关系.结果:乙酸酐与水杨酸的摩尔比为3:1、催化剂用量为水杨酸质量的14.50%、反应时间120 min、反应温度60 ℃时,乙酰水杨酸产率最高,为77.93%.结论:001×7强酸性苯乙烯系阳离子交换树脂对酯化反应催化效果好,副反应少,对环境污染小,能重复使用,值得大力推广.%Objective:To optimize the technology of synthesizing acetylsalicylic acid using 001 × 7 strong-acidic cation-exchange resin as catalyst . Methods : Orthogonal experiment was performed to examine the effect of molar ratio of reactants,reaction time, dosage of catalyst, and reaction temperature on the yield of product as well as the efficiency and frequencies of the resin recycled and shifted on the synthesis. Results :The optimal reaction conditions were 3:1 (the ratio of acetic anhydride to salicylic acid,n:n),in a dosage of the resin 14. 50% of salicylic acid,for the reaction time of 120 min at temperature of 60 ℃ , which led to a yield of 77.93 % . Conclusion: 001 × 7 strong-acidic cat ion-exchange resin works well on esterification reaction as a environmentally friendly catalyst and is worthy of wider use, for it has efficient activity, less adverse reaction and recyclable advantages.

  11. Novolak PF resins prepared from phenol liquefied Cryptomeria japonica and used in manufacturing moldings.

    Lee, Wen-Jau; Chen, Yi-Chun


    The wood of Japanese cedar (Cryptomeria japonica) was liquefied in phenol with H2SO4 and HCl as catalysts. The liquefied wood was reacted with formalin to prepare the novolak PF resin. The results showed that the reaction of liquefied Japanese cedar with formalin was an exothermic reaction, and formed a solid-like resin without extra heating. Two novolak PF resins were prepared from the liquefied wood which were identified as SF and CF that using the liquefied wood with H2SO4 and HCl as catalyst respectively. The novolak PF powder displayed thermo-melting characteristic. The resins of SF and CF had weight average molecular weight of 3638 and 3941 respectively and melting temperature of 149.4 degrees C and 127.5 degrees C respectively. Both of the novolak resins could be used to make moldings with good performance by mixing the novolak resin with wood powder, hardener and zinc stearate at the weight ratio of 60:30:10:1 and hot-pressed under 200 degrees C for 10min.

  12. Towards long-term stable solid state electrolyzers with infiltrated catalysts

    Ovtar, Simona; Chen, Ming; Brodersen, Karen

    performance of the fuel electrode of solid state electrolyzers (SOEC) will be presented. The infiltration process was optimized through choice of surfactants and concentrations of precursor solutions, to ensure easy penetration of the precursor solution into a Ni-YSZ (yttrium stabilized zirconia) composite...... manner. One of the promising solutions is the production of synthetic fuel by solid oxide electrolyzers. Electricity can be converted to gas and further to liquid products during times of electricity production excess. In times of need, these fuels can be converted back to electricity by either...... conventional power plants or fuel cells. Key challenges for a successful commercialization of solid oxide electrolyzers are up scale it, reduce cost and improve durability. Therefore, large efforts are allocated to improve cell performance. As a relatively novel method to introduce electro...

  13. An alternative preparation method for ion exchanged catalysts: Solid state redox reaction

    Schneider, E.; Hagen, A.; Grunwaldt, J.-D.


    A new method for modifying zeolites with zinc is proposed. The solid state redox reaction between metallic zinc and ZSM-5 zeolites with different Si/Al ratios was investigated by temperature programmed hydrogen evolution (TPHE), X-ray absorption near edge structure (XANES) and diffuse reflectance...... infrared Fourier transform spectroscopy (DRIFTS). The evolution of hydrogen was detected at temperatures above 620 K. The source of hydrogen was the solid state redox reaction of the metal with protons of the support. The samples exhibit catalytic activity in ethane aromatization indicating that zinc...

  14. A convenient synthesis of pyrroles catalyzed by acidic resin under solvent-free condition



    A convenient and effective Paal-Knorr condensations of 2,5-hexanedione with most amines have been carried out at room temperature under solvent-free condition. Macroporous strongly acidic styrol resin (D001) as a novel, efficient, cost-effective, and reusable solid acid catalyst for the synthesis of pyrroles under the same conditions. The pyrroles were obtained in high yields in short reaction times.

  15. Toughening of Epoxy Resin with Solid Amine Terminated Poly (ethy-lene glycol) Benzoate and Effect of Red Mud Waste Particles

    B.C.Samanta; T.Maity; S.Dalai; A.K.Banthia


    An investigation was carried out to modify the toughness of triethylene tetramine cured DGEBA (diglycidyl ether of bisphenol-A) resin using solid amine terminated poly (ethylene glycol) benzoate (ATPEGB) as modifier with and without red mud waste particles. The solid ATPEGB modifier synthesized from the acid catalyzed esterification reaction of poly (ethylene glycol) (PEG) and 4-amino benzoic acid was characterized by Fourier transform infrared spectroscopy (FT-IR) and 1H-NMR (nuclear magnetic resonance) spectroscopies, viscosity measurements, and solubility parameter calculation. The unfilled and red mud waste filled modified epoxy networks were evaluated with impact, adhesive, tensile, flexural and thermal properties by differential scanning calorimetry (DSC), thermogravimetric (TG) and dynamic mechanical analysis (DMA). The effect of modifier concentration and red mud waste particles on toughening behavior was also investigated. The optimum properties were obtained at 12.5 phr (parts per hundred parts of resin) concentration of the modifier. The ATPEGB modified cured epoxy was thermally stable up to 315℃. The morphology on fracture surfaces of cured epoxy was also analyzed by scanning electron microscopy (SEM).

  16. 炭基固体酸催化废油脂合成生物柴油动力学研究%Reaction Kinetics of Biodiesel Synthesis from Waste Oil Using a Carbon-based Solid Acid Catalyst

    舒庆; 高继贤; 廖玉会; 王金福


    The kinetics of simultaneous transesterification and esterification with a carbon-based solid acid catalyst was studied. Two solid acid catalysts were prepared by the sulfonation of carbonized vegetable oil asphalt and petroleum asphalt. These catalysts were characterized on the basis of elemental analysis, acidity site concentration, the Brunauer-Emmett-Teller (BET) surface area and pore size. The kinetic parameters with the two catalysts were determined, and the reaction system can be described as a pseudo homogeneous catalyzed reaction. All the forward and reverse reactions follow second order kinetics. The calculated concentration values from the kinetic equations are in good agreement with experimental values.

  17. N-Sulfonic acid poly(4-vinylpyridinum) hydrogen sulfate as a novel, efficient, and reusable solid acid catalyst for acylation under solvent-free conditions

    Nader Ghaffari Khaligh; Parisa Ghods Ghasem-Abadi


    N-Sulfonic acid poly(4-vinylpyridinum) hydrogen sulfate has been developed as a recyclable solid acid catalyst for the acetylation of alcohols, phenols, thiols, and amines, as well as the 1,1- diacetyla-tion of aldehydes under solvent-free conditions at room temperature. The acetylated products were formed in good to excellent yields over short reaction times, and the catalyst could be readily re-covered by filtration and used several times without any discernible loss in activity. The hydrogen sulfate anion of the catalytic system was found to play a critical role in enhancing the reaction time and yield of the acetylation reaction.



  19. Solid, double-metal cyanide catalysts for synthesis of hyperbranched polyesters and aliphatic polycarbonates

    Joby Sebastian; Srinivas Darbha


    Fe-Zn and Co-Zn double-metal cyanide (DMC) complexes exhibit highly efficient and selective catalytic activity for synthesis of hyperbranched polyesters (glycerol-succinic acid (G-SA) and glycerol-adipic acid (G-AA)) and aliphatic polycarbonates (via., alternative co-polymerization of cyclohexene oxide and CO2), respectively. The influence of method of preparation of DMC, in particular the mode of addition of reagents, on its physicochemical and catalytic properties was investigated. Co-Zn DMC was found highly selective for polycarbonate (than polyethers) formation. Catalysts prepared using tert-butanol and PEG-4000 as complexing and co-complexing agents, respectively, were found superior to those prepared without these agents. Apart from its role as a coordinating ligand, tert-butanol activated the Lewis acidic Zn2+ sites for reactions in polyester and polycarbonate formation. Hydrophobicity, micro-mesoporosity, acid strength and the amount of coordinated complexing agent are some of the crucial factors influenced the catalytic activity of DMC complexes.

  20. Building better lithium-sulfur batteries: from LiNO3 to solid oxide catalyst

    Ding, Ning; Zhou, Lan; Zhou, Changwei; Geng, Dongsheng; Yang, Jin; Chien, Sheau Wei; Liu, Zhaolin; Ng, Man-Fai; Yu, Aishui; Hor, T. S. Andy; Sullivan, Michael B.; Zong, Yun


    Lithium nitrate (LiNO3) is known as an important electrolyte additive in lithium-sulfur (Li-S) batteries. The prevailing understanding is that LiNO3 reacts with metallic lithium anode to form a passivation layer which suppresses redox shuttles of lithium polysulfides, enabling good rechargeability of Li-S batteries. However, this view is seeing more challenges in the recent studies, and above all, the inability of inhibiting polysulfide reduction on Li anode. A closely related issue is the progressive reduction of LiNO3 on Li anode which elevates internal resistance of the cell and compromises its cycling stability. Herein, we systematically investigated the function of LiNO3 in redox-shuttle suppression, and propose the suppression as a result of catalyzed oxidation of polysulfides to sulfur by nitrate anions on or in the proximity of the electrode surface upon cell charging. This hypothesis is supported by both density functional theory calculations and the nitrate anions-suppressed self-discharge rate in Li-S cells. The catalytic mechanism is further validated by the use of ruthenium oxide (RuO2, a good oxygen evolution catalyst) on cathode, which equips the LiNO3-free cell with higher capacity and improved capacity retention over 400 cycles.

  1. Characterization of CuO Species and Thermal Solid-Solid Interaction in CuO/CeO2-Al2O3 Catalyst by In-Situ XRD, Raman Spectroscopy and TPR

    He Mai; Luo Mengfei; Fang Ping


    Transference of CuO species and thermal solid-solid interaction in CuO/CeO2-Al2O3 catalyst prepared by an impregnation method were characterized by in-situ XRD, Raman spectroscopy and H2-TPR techniques.For the catalyst calcined at 300 ℃, two kinds of CuO species coexist on the surface, that is, highly dispersed and bulk CuO crystalline phase.Four kinds of CuO species are present for the catalyst calcined at 600 ℃: (1) highly dispersed CuO, (2) bulk CuO on the surface, (3) bulk CuO in the internal layer of CeO2, and (4) CuAl2O4 formed from CuO-Al2O3 interaction.For the catalyst calcined at 800 ℃, besides very little highly dispersed and bulk CuO on the surface, most of the CuO has transferred into the internal layer of CeO2 and the mass of CuAl2O4 are increased.At 900 ℃, all of CuO has diffused into the internal layer of CeO2 and formed CuAl2O4.The results show that the distribution of CuO species in the catalysts depends on the calcination temperature;the different CuO species can be effectively confirmed by in-situ XRD, Raman spectroscopy and H2-TPR techniques.

  2. Synthesis of SO4 2-/Zr-silicalite-1 zeolite catalysts for upgrading and visbreaking of heavy oil

    Su, Lu; Guan, Zhongjie; Li, Qiuye; Li, Chen; Wang, Xiaodong; Li, Xiaohong; Yang, Jianjun; Zhang, Zhijun


    Catalyst is crucially important to reduce the viscosity of heavy oil during the catalytic aquathermolysis. SO4 2--modified ZrO2-based nanoparticle catalyst is a commonly used catalyst. But less acid sites and poor hydrothermal stability limited further improving its catalytic performance and practical application. In this study, the Zr -doped silicalite zeolite catalysts with large surface area were prepared as a support matrix, and SO4 2--modified Zr-doped silicalite zeolite (denoted as SO4 2-/Zr-silicalite-1 zeolite) was used as a solid superacid catalyst to crack the heavy oil. A reference catalyst of SO4 2-/Zr-SiO2 nanoparticles (NPs) was also prepared, which has the same composition with the SO4 2-/Zr-silicalite-1 zeolite catalyst. Compared with the SO4 2-/Zr-SiO2 NP catalyst, the amount of acid sites for the SO4 2-/Zr-silicalite-1 zeolite catalyst is significantly increased and the viscosity reduction efficiency is also enhanced by 40%. More importantly, the SO4 2-/Zr-silicalite-1 zeolite catalyst exhibits a high hydrothermal stability. After catalytic aquathermolysis, the quality of the heavy oil was also ameliorated. The heavy resins and asphaltenes reduced, while the light saturated and aromatic hydrocarbon increased. The results suggest metal element-doped silicalite zeolite catalyst is a potential useful way to solving the less acid sites and poor hydrothermal stability for the SO4 2--modified nanoparticle catalyst. [Figure not available: see fulltext.

  3. Conversion of polar and non-polar algae oil lipids to fatty acid methyl esters with solid acid catalysts--A model compound study.

    Asikainen, Martta; Munter, Tony; Linnekoski, Juha


    Bio-based fuels are becoming more and more important due to the depleting fossil resources. The production of biodiesel from algae oil is challenging compared to terrestrial vegetable oils, as algae oil consists of polar fatty acids, such as phospholipids and glycolipids, as well as non-polar triglycerides and free fatty acids common in vegetable oils. It is shown that a single sulphonated solid acid catalyst can perform the esterification and transesterification reactions of both polar and non-polar lipids. In mild reaction conditions (60-70 °C) Nafion NR50 catalyst produces methyl palmitate (FAME) from the palmitic acid derivatives of di-, and tri-glyceride, free fatty acid, and phospholipid with over 80% yields, with the glycolipid derivative giving nearly 40% yields of FAME. These results demonstrate how the polar and non-polar lipid derivatives of algal oil can be utilised as feedstocks for biodiesel production with a single catalyst in one reaction step.

  4. Preparation of biodiesel from cottonseed oil catalyzed by solid based catalyst%固体碱催化棉籽油制备生物柴油

    姜绍通; 徐涟漪; 周勤丽; 潘丽军; 张福建; 张轶


    In order to study the related technology for preparing biodiesel by transesterification of cottonseed oil using solid based catalyst, with supported solid base Na3PO4/MgO as catalyst and biodiesel conversion rate as index, the optimum conditions for catalyst preparation were analyzed by single-factor and orthogonal experiments. The catalyst was characterized by methods of XRD, SEM and TG. Furthermore, the transesterification conditions from cottonseed oil to biodiesel were investigated using solid base catalyst. It was obtained that the optimum conditions for catalyst preparation were: 32% of Na3PO4 dosage on MgO, 600℃ of roasting temperature, 3 h of roasting time and 70℃ of blending temperature. Catalytic activity was related to Na3PO4 crystalline phase. The optimal conditions of transesterification with optimized catalyst were:2.5 h of reaction time, 70℃ of reaction temperature, 15:1 of mass ratio of methanol to oil, 5% of quality ratio of catalyst to oil.%为研究采用固体碱催化剂催化制备生物柴油的相关技术,以棉籽油为对象,选用Na3PO4/MgO负载型固体碱为催化剂,以棉籽油的生物柴油转换率为指标,通过单因素和正交试验,分析催化剂的最佳制备工艺,并对催化剂进行X射线衍射、扫描电镜和热重表征分析.在此基础上对该催化剂催化棉籽油制备生物柴油的工艺进行探讨.研究结果表明,催化剂的最佳制备工艺为:Na3PO4负载量32%,焙烧温度600℃,焙烧时间3 h,共混温度70℃;使用优选的催化剂制备生物柴油的工艺条件为:反应时间2.5h,反应温度70℃,醇油摩尔比15:1,催化剂用量5%;催化剂的活性与N%PO4晶相有关.

  5. Effect of catalyst diameter on vapour-liquid-solid growth of GaAs nanowires

    O' Dowd, B. J., E-mail:; Shvets, I. V. [CRANN, School of Physics, Trinity College, the University of Dublin, Dublin D2 (Ireland); Wojtowicz, T.; Kolkovsky, V.; Wojciechowski, T.; Zgirski, M. [Institute of Physics, Polish Academy of Sciences, Warsaw 02-668 (Poland); Rouvimov, S. [Notre Dame Integrated Imaging Facility (NDIIF), University of Notre Dame, Notre Dame, Indiana 46556 (United States); Liu, X.; Pimpinella, R.; Dobrowolska, M.; Furdyna, J. [Department of Physics, University of Notre Dame, Notre Dame, Indiana 46556 (United States)


    GaAs nanowires were grown on (111)B GaAs substrates using the vapour-liquid-solid mechanism. The Au/Pt nanodots used to catalyse wire growth were defined lithographically and had varying diameter and separation. An in-depth statistical analysis of the resulting nanowires, which had a cone-like shape, was carried out. This revealed that there were two categories of nanowire present, with differing height and tapering angle. The bimodal nature of wire shape was found to depend critically on the diameter of the Au-Ga droplet atop the nanowire. Transmission electron microscopy analysis also revealed that the density of stacking faults in the wires varied considerably between the two categories of wire. It is believed that the cause of the distinction in terms of shape and crystal structure is related to the contact angle between the droplet and the solid-liquid interface. The dependency of droplet diameter on contact angle is likely related to line-tension, which is a correction to Young's equation for the contact angle of a droplet upon a surface. The fact that contact angle may influence resulting wire structure and shape has important implications for the planning of growth conditions and the preparation of wires for use in proposed devices.

  6. Solar photocatalytic treatment of landfill leachate using a solid mineral by-product as a catalyst.

    Poblete, Rodrigo; Prieto-Rodríguez, Lucia; Oller, Isabel; Maldonado, Manuel I; Malato, Sixto; Otal, Emilia; Vilches, Luis F; Fernández-Pereira, Constantino


    The treatment of municipal solid waste landfill leachate in a pilot plant made up of solar compound parabolic collectors, using a solid industrial titanium by-product (WTiO(2)) containing TiO(2) and Fe(III) as a photocatalyst, was investigated. In the study evidence was found showing that the degradation performed with WTiO(2) was mainly due to the Fe provided by this by-product, instead of TiO(2). However, although TiO(2) had very little effect by itself, a synergistic effect was observed between Fe and TiO(2). The application of WTiO(2), which produced coupled photo-Fenton and heterogeneous catalysis reactions, achieved a surprisingly high depuration level (86% of COD removal), higher than that reached by photo-Fenton using commercial FeSO(4) (43%) in the same conditions. After the oxidation process the biodegradability and toxicity of the landfill leachate were studied. The results showed that the leachate biodegradability was substantially increased, at least in the first stages of the process, and again that WTiO(2) was more efficient than FeSO(4) in terms of increasing biodegradability. Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. SnxTi1-xO2 Solid Solution Catalysts for Nitrogen Oxide Selective Catalytic Reduction by Propene in Presence of Oxygen

    尉继英; 马军; 朱月香; 蔡小海; 谢有畅


    A series of SnO2-TiO2 binary oxide catalysts prepared by cocurrent precipitation method was found to be a novel and good system for the selective catalytic reduction of NO by propene in the presence of oxygen with high activity and good selectivity to N2. The NO conversion to N2 over SnO2-TiO2 oxide catalysts varied with SnO2 content and attainted a maximum at 65% over the catalyst with SnO2 content at 40wt% for a feed with 1186 ppm NO, 948 ppm propene and 2.23% O2 in He and a space velocity of 15000 h-1 at 350℃. The SnO2-TiO2catalysts could sustain moderate activity in the presence of 10% steam. Because of the identical valence and the similar radius of Sn4+ and Ti4+ , SnO2-TiO2 binary oxides can form solid solution in three different phases as proved by XRD,electron diffraction and TPR. Sn4+ is the main active species in the SnO2-TiO2 catalysts, and it is enriched on the solid solution surface as tested by XPS analysis. H2-TPR, NH3-TPD and BET tests show that SnO2-TiO2 solid solution can dilute SnO2 and suppress the activity of propene complete oxidation over SnO2. This may be beneficial to the reactivity enhancement of NO conversion.

  8. A green and efficient protocol for the synthesis of quinoxaline, benzoxazole and benzimidazole derivatives using heteropolyanion-based ionic liquids: as a recyclable solid catalyst.

    Vahdat, Seyed Mohammad; Baghery, Saeed


    In this paper, we introduce two nonconventional ionic liquid compounds which are composed of propane sulfonate functionalized organic cations and heteropolyanions as green solid acid catalysts for the highly efficient and green synthesis of 2,3-disubstitutedquinoxaline derivatives. These ionic liquids are in the solid state at room temperature and the synthesis is carried out via the one-pot condensation reaction of various o-phenylenediamine with 1,2-diketone derivatives. Benzoxazole and benzimidazole derivatives were also synthesized by these novel catalysts via the one-pot condensation from reaction orthoester with o-aminophenol (synthesis of benzoxazole derivatives) and ophenylenediamine (synthesis of benzimidazole derivatives). All experiments successfully resulted in the desired products. The described novel synthesis method has several advantages of safety, mild condition, high yields, short reaction times, simplicity and easy workup compared to the traditional method of synthesis.

  9. Synthesis of biodiesel from waste vegetable oil with large amounts of free fatty acids using a carbon-based solid acid catalyst

    Shu, Qing; Gao, Jixian; Nawaz, Zeeshan; Liao, Yuhui; Wang, Dezheng; Wang, Jinfu [Beijing Key Laboratory of Green Chemical Reaction Engineering and Technology, Department of Chemical Engineering, Tsinghua University, Beijing 100084 (China)


    A carbon-based solid acid catalyst was prepared by the sulfonation of carbonized vegetable oil asphalt. This catalyst was employed to simultaneously catalyze esterification and transesterification to synthesis biodiesel when a waste vegetable oil with large amounts of free fatty acids (FFAs) was used as feedstock. The physical and chemical properties of this catalyst were characterized by a variety of techniques. The maximum conversion of triglyceride and FFA reached 80.5 wt.% and 94.8 wt.% after 4.5 h at 220 C, when using a 16.8 M ratio of methanol to oil and 0.2 wt.% of catalyst to oil. The high catalytic activity and stability of this catalyst was related to its high acid site density (-OH, Broensted acid sites), hydrophobicity that prevented the hydration of -OH species, hydrophilic functional groups (-SO{sub 3}H) that gave improved accessibility of methanol to the triglyceride and FFAs, and large pores that provided more acid sites for the reactants. (author)

  10. Nucleophilic substitution reactions of alcohols with use of montmorillonite catalysts as solid Brønsted acids.

    Motokura, Ken; Nakagiri, Nobuaki; Mizugaki, Tomoo; Ebitani, Kohki; Kaneda, Kiyotomi


    We have developed an environmentally benign synthetic approach to nucleophilic substitution reactions of alcohols that minimizes or eliminates the formation of byproducts, resulting in a highly atom-efficient chemical process. Proton- and metal-exchanged montmorillonites (H- and Mn+-mont) were prepared easily by treating Na+-mont with an aqueous solution of hydrogen chloride or metal salt, respectively. The H-mont possessed outstanding catalytic activity for nucleophilic substitution reactions of a variety of alcohols with anilines, because the unique acidity of the H-mont catalyst effectively prevents the neutralization by the basic anilines. In addition, amides, indoles, 1,3-dicarbonyl compounds, and allylsilane act as nucleophiles for the H-mont-catalyzed substitutions of alcohols, which allowed efficient formation of various C-N and C-C bonds. The solid H-mont was reusable without any appreciable loss in its catalytic activity and selectivity. Especially, an Al3+-mont showed high catalytic activity for the alpha-benzylation of 1,3-dicarbonyl compounds with primary alcohols due to cooperative catalysis between a protonic acid site and a Lewis acidic Al3+ species in its interlayer spaces.

  11. Solid-state synthesis of ordered mesoporous carbon catalysts via a mechanochemical assembly through coordination cross-linking

    Zhang, Pengfei; Wang, Li; Yang, Shize; Schott, Jennifer A.; Liu, Xiaofei; Mahurin, Shannon M.; Huang, Caili; Zhang, Yu; Fulvio, Pasquale F.; Chisholm, Matthew F.; Dai, Sheng


    Ordered mesoporous carbons (OMCs) have demonstrated great potential in catalysis, and as supercapacitors and adsorbents. Since the introduction of the organic-organic self-assembly approach in 2004/2005 until now, the direct synthesis of OMCs is still limited to the wet processing of phenol-formaldehyde polycondensation, which involves soluble toxic precursors, and acid or alkali catalysts, and requires multiple synthesis steps, thus restricting the widespread application of OMCs. Herein, we report a simple, general, scalable and sustainable solid-state synthesis of OMCs and nickel OMCs with uniform and tunable mesopores (~4-10 nm), large pore volumes (up to 0.96 cm3 g-1) and high-surface areas exceeding 1,000 m2 g-1, based on a mechanochemical assembly between polyphenol-metal complexes and triblock co-polymers. Nickel nanoparticles (~5.40 nm) confined in the cylindrical nanochannels show great thermal stability at 600 °C. Moreover, the nickel OMCs offer exceptional activity in the hydrogenation of bulky molecules (~2 nm).

  12. 高分子量热固性酚醛树脂的合成与性能%Synthesis and Property of Solid Resol Phenolic Resins with High Molecular Weight

    杨丽君; 王明存


    In this paper the solid resol phenolic resins with high molecular weight were synthesized via a two-step protocol: firstly the Novolac phenolic resins as the raw materials were prepared; then the methylolation was conducted under alkaline catalysis to get resol phenolic resins. With the molecular weight of Novolac resin increasing, the gelation time of resol phenolic resins gradually decreases (all the resins can be cured in 3 rain at 150 ℃ ), while the viscosity of the corresponding resin's solution becomes higher. The dosage of HCHO increasing makes the viscosity of corresponding resin's solution higher. The influence of reaction time to resin's solution is ignorable after 12 h.%采用两步法,先合成热塑性酚醛树脂母体,再对其进行羟甲基化反应得到相对分子量800以上的热固性酚醛树脂。随树脂分子量增大,其凝胶时间缩短,在150℃可以实现〈3min内完全固化。同时随着原料Novolae树脂分子量增大,其改性后树脂溶液的黏度呈增长趋势,凝胶时间缩短;羟甲基化率(决定于甲醛用量)的增加可显著降低改性后树脂溶液的凝胶时间,但对溶液黏度的影响不明显;而反应时间在12h后对于凝胶时间和溶液黏度影响很小。

  13. Sulfanilic acid functionalized mesoporous SBA-15: A water-tolerant solid acid catalyst for the synthesis of uracil fused spirooxindoles as antioxidant agents

    Robabeh Baharfar; Razieh Azimi


    Incorporating sulfanilic acid as a hydrophobic Brønsted acid inside the nanospaces of SBA-15 led to a water-tolerant solid acid catalyst, SBA-15-PhSO 3 H, which showed excellent catalytic performance in synthesis of uracil-fused spirooxindoles in aqueous ethanol. The synthesized compounds were evaluated for their antioxidant activity by 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay.

  14. Solid Phase Extraction and Determination of Nickel in Water Samples by Using Novel Thiol-Containing Sulfonamide Polymeric Resin and Atomic Absorption Spectrophotometer

    Nagihan M Karaaslan; B Filiz Senkal; Cigdem Er; Halim Avci; Mehmet Yaman


    Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry.In this study,thiol-containing sulfonamide resin was synthesized,characterized and applied as a new sorption material for solid phase extraction of nickel in drinking water samples.After preconcentration procedure,flame atomic absorption spectrometry was used for determinations.Optimum parameters were found to be pH=3.2,contact time =20 min and eluate volume=3 mL.The limit of detection was found to be 0.75 ng · mL-1.The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent,high sorption capacity as well as the relatively fast extraction rate.The Ni concentrations in the studied 21 kind of water samples were found to be in the range of BDL-4.0 ng ·mL-1.



    The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin isreported. 2-Polystyrylsuifonamidoethanol resin 1 was reacted with acryloyl chloride to afford2-polystyrylsulfonylamidoethyl acrylate resin 2, which was further reacted with brominatedaldoximes by [3+2] cycioaddition to give isoxazoline resin 4. Resin 4 was treated with aqueous 6mol/L HCI solution to obtain isoxazolines in good yield and purity.

  16. Nanostructured Polyphase Catalysts Based on the Solid Component of Welding Aerosol for Ozone Decomposition

    Rakitskaya, Tatyana; Truba, Alla; Ennan, Alim; Volkova, Vitaliya


    Samples of the solid component of welding aerosols (SCWAs) were obtained as a result of steel welding by ANO-4, TsL-11, and UONI13/55 electrodes of Ukrainian manufacture. The phase compositions of the samples, both freshly prepared (FP) and modified (M) by water treatment at 60 °C, were studied by X-ray phase analysis and IR spectroscopy. All samples contain magnetite demonstrating its reflex at 2 θ ~ 35° characteristic of cubic spinel as well as manganochromite and iron oxides. FP SCWA-TsL and FP SCWA-UONI contain such phases as CaF2, water-soluble fluorides, chromates, and carbonates of alkali metals. After modification of the SCWA samples, water-soluble phases in their composition are undetectable. The size of magnetite nanoparticles varies from 15 to 68 nm depending on the chemical composition of electrodes under study. IR spectral investigations confirm the polyphase composition of the SCWAs. As to IR spectra, the biggest differences are apparent in the regions of deformation vibrations of M-O-H bonds and stretching vibrations of M-O bonds (M-Fe, Cr). The catalytic activity of the SCWAs in the reaction of ozone decomposition decreases in the order SCWA-ANO > SCWA-UONI > SCWA-TsL corresponding to the decrease in the content of catalytically active phases in their compositions.

  17. Synthesis of methyl esters from palm (Elaeis guineensis) oil using cobalt doped MgO as solid oxide catalyst.

    Rahman, Nur Ashikin Ab; Olutoye, M A; Hameed, B H


    The potential of Mg(x)Co(2-)(x)O(2) as heterogeneous reusable catalyst in transesterification of palm oil to methyl ester was investigated. The catalyst was prepared via co-precipitation of the metal hydroxides at different Mg-Co ratios. Mg(1.7)Co(0.3)O(2) catalyst was more active than Mg(0.3)Co(1.7)O(2) in the transesterification of palm oil with methanol. The catalysts calcined at temperature 300 °C for 4 h resulted in highly active oxides and the highest transesterification of 90% was achieved at methanol/oil molar ratio of 9:1, catalyst loading of 5.00 wt.%, reaction temperature of 150 °C and reaction time of 2 h. The catalyst could easily be removed from reaction mixture, but showed 50% decrease in activity when reused due to leaching of active sites. Copyright © 2011 Elsevier Ltd. All rights reserved.

  18. Aldol condensations of a variety of different aldehydes and ketones under ultrasonic irradiation using poly(N-vinylimidazole) as a new heterogeneous base catalyst under solvent-free conditions in a liquid-solid system

    Nader Ghaffari Khaligh; Taraneh Mihankhah


    An ultrasound-assisted aldol condensation reaction has been developed for a range of ketones with a variety of aromatic aldehydes using poly(N-vinylimidazole) as a solid base catalyst in a liquid-solid system. The catalyst can be recovered by simple filtration and reused at least 10 times without any significant reduction in its activity. The reaction is also amenable to the large scale, making the pro-cedure potentially useful for industrial applications.

  19. Application of epoxy resin to a solid-foam pelvic model: creating a dry-erase pelvis.

    Weaver, Michael J; Brubacher, Jacob W; Vrahas, Mark S


    The value of preoperative planning and templating has been well-established in fracture surgery. We have found that using 3-dimensional (3-D) models in preoperative planning aids in the understanding of anatomy, fracture-reduction techniques, and fixation methods, particularly in pelvic and acetabular fractures. To facilitate the correction of errors and reuse for future cases, we coat pelvic models with dry-erase epoxy resin. Fracture lines and planned implants are drawn onto the models with dry-erase markers. The creation of 3-D planning tools is useful in understanding the anatomy of pelvic and acetabular fractures.

  20. High efficient acetalization of carbonyl compounds with diols catalyzed by novel carbon-based solid strong acid catalyst


    The novel carbon-based acid catalyst has been applied to catalyzing the acetalization and ketalization. The results showed that the catalyst was very efficient with the average yield over 93%. The novel heterogeneous catalyst has the advantages of high activity, wide applicability even to 7-membered ring acetals, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the green process greatly.

  1. Nanostructured gadolinium-doped ceria microsphere synthesis from ion exchange resin: Multi-scale in-situ studies of solid solution formation

    Caisso, Marie [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France); Institut Européen des Membranes, UMR 5635 CNRS-ENSCM-UM2, CC047, Université Montpellier 2, F-34095 Montpellier Cedex 5 (France); Lebreton, Florent; Horlait, Denis [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France); Picart, Sébastien [CEA, DEN, DRCP/SERA/LCAR, F-30207 Bagnols-sur-Cèze Cedex (France); Martin, Philippe M.; Bès, René [CEA, DEN, DEC/SESC/LLCC, F-13108 Saint-Paul-Lez-Durance Cedex (France); Renard, Catherine; Roussel, Pascal [Unité de Catalyse et Chimie du Solide, UMR 8012 CNRS, Ecole Nationale Supérieure de Chimie de Lille BP 90108, 59652 Villeneuve d’Ascq Cedex (France); Neuville, Daniel R. [Institut de Physique du Globe de Paris-CNRS, Géochimie and Cosmochimie, 1 rue Jussieu, 75005 Paris (France); Dardenne, Kathy; Rothe, Jörg [Karlsruhe Institute of Technology, Institute for Nuclear Waste Disposal (KIT-INE), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany); Delahaye, Thibaud, E-mail: [CEA, DEN, DTEC/SDTC/LEMA, F-30207 Bagnols-sur-Cèze Cedex (France); Ayral, André [Institut Européen des Membranes, UMR 5635 CNRS-ENSCM-UM2, CC047, Université Montpellier 2, F-34095 Montpellier Cedex 5 (France)


    In the current nano-sized material revolution, the main limitations to a large-scale deployment of nanomaterials involve health concerns related to nano-dissemination via air. Developing new chemical routes benefiting from nano-size advantages while avoiding their hazards could overcome these limitations. Addressing this need, a chemical route leading to soft nano-particle agglomerates, i.e., macroscopic precursors presenting the ability to be decomposed into nano-sized materials, was developed and applied to Ce{sub 0.8}Gd{sub 0.2}O{sub 2−δ}. Using cerium/gadolinium-loaded ion exchange resin, the Ce{sub 0.8}Gd{sub 0.2}O{sub 2−δ} solid solution formation as a function of temperature was studied in-situ through X-ray diffraction, X-ray absorption spectroscopy and Raman spectroscopy. Temperatures corresponding to the organic skeleton decomposition and to the mixed oxide crystallization were identified. An optimal heat treatment, leading to nanostructured soft agglomerates, was established. Microsphere processing capabilities were evaluated and particle size distribution measurements were recorded. A very low fracture strength was calculated, and a nanometric particle size distribution (170 nm) was determined. - Graphical abstract: The elaboration of micro-spherical precursors leading to the formation of nano-oxide soft agglomerates was studied and approved through the use of ion exchange resin loaded with cerium and gadolinium. The formation of the solid solution was followed through in-situ measurements such as XAS, XRD, Raman, TGA and DSC. Key temperatures were identified for the formation of the mixed-oxide. Following this study, the microstructure and particle size of oxide microspheres formed highlight the formation of soft nano-arrangments. - Highlights: • Soft microspherical agglomerates able to be decomposed into nano-sized materials. • In situ study of cerium/gadolinium-loaded ion exchange resin conversion in oxide. • In situ multi-scale study

  2. Perfluorosulfonic acid resin catalyst for dimethyl ether synthesis by methanol dehydration%甲醇制二甲醚用全氟磺酸树脂催化剂的研究

    史立杰; 李晨佳; 常俊石


    A new catalyst perfluorosulfonate resin/SiO2 for vapor phase dehydration of methanol(Me) to dimethyl ether(DME) was prepared by sol-gel method. The as-prepared catalyst was characterized by X-ray diffraction,Fourier transform infrared spectroscopy,thermogravimetry-dirfferential scanning calorimetry , low-temperature nitrogen adsorption method and NH3 temperature-programmed desorption. The effects of reaction conditions such as temperature,liquid hourly space velocity (LHSV) and active component content on the reaction performance and catalyst stability were investigated. The results indicated that the BET specific surface area of microporous catalyst was 820m2/g. After a continuous run under conditions:w(PFSA)=10.0%,LHSV(Me)=1h-1,t=184℃,it is found that the activity and stability of the catalyst kept steady with the Me conversion,DME selectivity being>91.5%,>99.9%respectively.%采用溶胶-凝胶法制备了用于甲醇气相脱水制二甲醚的新型催化剂全氟磺酸树脂/二氧化硅,应用X射线衍射、红外光谱、热重-差示扫描量热、低温氮物理吸附和氨程序升温脱附法对所得催化剂进行了表征。考察了反应温度、甲醇液空速、全氟磺酸树脂含量对甲醇气相催化脱水制二甲醚反应性能和催化剂稳定性的影响。结果表明,催化剂比表面积达820m2/g,在全氟磺酸树脂负载量10.0%、甲醇液空速1h-1、反应温度184℃时,甲醇转化率92.0%,二甲醚选择性99.9%,经350h实验测试,活性和稳定性没有明显变化。

  3. Synthesis, characterization and application of a nano-manganese-catalyst as an efficient solid catalyst for solvent free selective oxidation of ethylbenzene, cyclohexene, and benzylalcohol

    Habibi, Davood; Faraji, Ali Reza


    The object of this study is to synthesize the heterogeneous Mn-nano-catalyst (MNC) which has been covalently anchored on a modified nanoscaleSiO2/Al2O3, and characterized by FT-IR, UV-Vis, CHN elemental analysis, EDS, TEM, and EDX. The method is efficient for the highly selective oxidation of ethylbenzene, cyclohexene, and benzylalcohol without the need to any solvents, using tert-butyl hydroperoxide (TBHP) as an oxidant. Oxidation of ethylbenzene, cyclohexene, and benzylalcohol gave acetophenone, 2-cyclohexene-1-one and benzaldehyde, respectively, as major products. Reaction conditions have been optimized by considering the effect of various factors such as reaction time, amounts of substrates and oxidant, Mn-nano-catalyst and application of various solvents.

  4. Oil palm trunk and sugarcane bagasse derived solid acid catalysts for rapid esterification of fatty acids and moisture-assisted transesterification of oils under pseudo-infinite methanol.

    Ezebor, Francis; Khairuddean, Melati; Abdullah, Ahmad Zuhairi; Boey, Peng Lim


    The use of pseudo-infinite methanol in increasing the rate of esterification and transesterification reactions was studied using oil palm trunk (OPT) and sugarcane bagasse (SCB) derived solid acid catalysts. The catalysts were prepared by incomplete carbonisation at 400°C for 8h, followed by sulfonation at 150°C for 15h and characterised using TGA/DTA, XRD, FT-IR, SEM-EDS, EA and titrimetric determinations of acid sites. Under optimal reaction conditions, the process demonstrated rapid esterification of palmitic acid, with FAME yields of 93% and 94% in 45min for OPT and SCB catalysts, respectively. With the process, moisture levels up to 16.7% accelerated the conversion of low FFA oils by sulfonated carbon catalysts, through moisture-induced violent bumping. Moisture assisted transesterification of palm olein containing 1.78% FFA and 8.33% added water gave FAME yield of 90% in 10h, which was two folds over neat oil.

  5. Selective hydrogenation of 1,3-butadiene from crude C{sub 4} cracker stream with a solid catalyst with ionic liquid layer (SCILL). DSC and solubility study

    Mangartz, T.; Korth, W.; Kern, C.; Jess, A. [Bayreuth Univ. (Germany). Dept. of Chemical Engineering


    In petroleum as well as in fine chemical industry, selective catalytic hydrogenation is an important reaction. The selective hydrogenation of 1,3-butadiene (BD) to butene (trans-,1- and cis-butene) from the crude C4 steam cracker fraction represents one example, but under today's technical conditions undesired butane forms inevitably in relevant amounts. To increase the butene yield, the concept of Solid Catalyst with Ionic Liquid Layer (SCILL) was employed. The SCILL catalyst, in contrast to the uncoated catalyst, yielded a remarkably high selectivity to butenes (S{sub butenes} > 99 %) even at high residence times or at high hydrogen partial pressure. Nearly no butane (S{sub butane} {approx} 0 %) was analytically detected. We expected that due to different solubility, the poorer soluble compounds discharged from the ionic liquid and, thus, caused the shift in selectivity to a great extent. Temperature dependent solubility measurements in the used ionic liquid ([DMIM][DMP]) revealed that the order of increasing solubility is 1,3-butadiene > butenes > butane which matches the assumption. However, since differences in solubility cannot explain this SCILL effect satisfyingly, ionic liquids are expected to affect the surface of the catalyst (side-specific ligand-type effect). Investigations using spectroscopic methods (e.g. FTIR) confirmed this suggestion. (orig.)

  6. Cobalt Ions Improve the Strength of Epoxy Resins

    Stoakley, D. M.; St. Clair, A. K.


    Technique developed for improving mechanical strength of epoxy resins by adding cobalt ions in form of tris(acetylacetonato)cobalt (III) complex. Solid cast disks prepared from cobalt ion-containing epoxy resins tested for flexural strength and stiffness. Incorporation of cobalt ions into epoxies increased flexural strength of resins by 10 to 95 percent. Suitable resins for this technique include any liquid or solid TGMDA resins. Improved epoxy formulation proves useful as composite matrix resin, adhesive, or casting resin for applications on commercial and advanced aircraft.

  7. Porous polymers bearing functional quaternary ammonium salts as efficient solid catalysts for the fixation of CO2 into cyclic carbonates

    Cai, Sheng; Zhu, Dongliang; Zou, Yan; Zhao, Jing


    A series of porous polymers bearing functional quaternary ammonium salts were solvothermally synthesized through the free radical copolymerization of divinylbenzene (DVB) and functionalized quaternary ammonium salts. The obtained polymers feature highly cross-linked matrices, large surface areas, and abundant halogen anions. These polymers were evaluated as heterogeneous catalysts for the synthesis of cyclic carbonates from epoxides and CO2 in the absence of co-catalysts and solvents. The results revealed that the synergistic effect between the functional hydroxyl groups and the halide anion Br- afforded excellent catalytic activity to cyclic carbonates. In addition, the catalyst can be easily recovered and reused for at least five cycles without significant loss in activity.

  8. The modification of ion exchange heterogeneous catalysts for biodiesel synthesis

    Hartono, R.; Mulia, B.; Sahlan, M.; Utami, T. S.; Wijanarko, Anondho; Hermansyah, Heri


    Conventionally, biodiesel is produced by using the homogeneous catalyst which has difficulty in high cost of the separation process. The heterogeneous catalysts ion exchange resin by its Solid phase can make an easier separation process, able to be reactivated and used repeatedly. In this research, the heterogeneous catalyst from various source such as Lewatit macro porous resin, Amberlite gel resin and natural zeolite bayah was investigated their performance to produced biodiesel from used cooking oil. Initially, the preparation of the ion exchange process with variations in time, temperature, the concentration of HCl and NaOH solution was investigated. Then, the activity of heterogeneous catalyst to produced biodiesel under the variation of stirring rate, zeolite particle size, and comparison of different ion exchange catalysts were also investigated. Finally, the stability test and regeneration treatment were also investigated. The optimum operating conditions of biodiesel synthesis process is at the temperature of 60 °C for 2 h with a stirring speed of 700 rpm. Natural zeolite Bayah with 6 M of NaOH solution produced 16.19%, Amberlite gel with 6 M HCL produced 65.22% of biodiesel yield and material Lewatit macro porous with 6 M of NaOH solution produced 85.94% as the maximum result. As the best result, Material Lewatit macro porous selected as the material which was used in the variation of stirring speed, temperature, and reaction time, the concentration of base and stability test. According to the results of analysis, calculations yield methyl oleic HPLC produced by Lewatit macro porous with 6 M NaOH at 62.95%.

  9. New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+ as a Green Solid Catalyst

    Lahouaria Medjdoub


    Full Text Available Nucleophilic substitution on hexachlorocyclotriphosphazene (HCCTP with allylamine in order to give hexa(allylaminocyclotriphosphazene (HACTP  is performed for the first time under mild conditions by using diethylether as solvent to replace benzene which is very toxic. The reaction time is reduced to half and also performed at room temperature but especially in the presence of an eco-catalyst called Maghnite-H+. This catalyst has a significant role in the industrial scale. In fact, the use of Maghnite is preferred for its many advantages: a very low purchase price compared to other catalysts, the easy removal of the reaction mixture. Then, Maghnite-H+ is became an excellent catalyst for many chemical reactions. The structure of HACTP synthesized in the presence of Maghnite-H+ to 5% by weight is confirmed by 1H-NMR, 13C-NMR, 31P-NMR (Nuclear magnetic resonance and FTIR (Fourier Transform Infrared spectroscopy. MALDI-TOF (Matrix-Assisted Laser Desorption/Ionisation-time-of-flight mass spectrometry is used to establish the molecular weight of HACTP which is 471 g/mol. DSC (Differential Scanning Calorimetery and TGA (Thermogravimetric Analysis show that HACTP is a crystalline product with a melting point of 88 °C. It is reactive after melting but is degraded from 230 °C. Copyright © 2016 BCREC GROUP. All rights reserved Received: 28th September 2015; Revised: 5th December 2015; Accepted: 4th January 2016 How to Cite: Medjdoub, L., Mohammed, B. (2016. New Method for Nucleophilic Substitution on Hexachlorocyclotriphosphazene by Allylamine Using an Algerian Proton Exchanged Montmorillonite Clay (Maghnite-H+ as a Green Solid Catalyst. Bulletin of Chemical Reaction Engineering & Catalysis, 11 (2: 151-160 (doi:10.9767/bcrec.11.2.541.151-160 Permalink/DOI:

  10. Easy solid-phase synthesis of pH-insensitive heterogeneous CNTs/FeS Fenton-like catalyst for the removal of antibiotics from aqueous solution.

    Ma, Jie; Yang, Mingxuan; Yu, Fei; Chen, Junhong


    We report a facile solid method to synthesize efficient carbon-based Fenton-like catalyst (CNTs/FeS) using as-prepared carbon nanotubes (APCNTs), which makes full use of the iron nanoparticles in APCNTs without needless purification. Furthermore, the CNTs/FeS was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric (TG) and other analysis techniques, and then the CNTs/FeS was used as a Fenton-like catalyst for removing ciprofloxacin from aqueous solution. Response Surface Methodology (RSM) was applied to find the effect of the reaction parameter and the optimum operating condition. Results shows the catalytic reaction had better suitability than previous studies in a wide range of pH values (pH 3-8) and the Fenton-like catalyst CNTs/FeS exhibits good catalytic activity for removing of antibiotic, which be attributed to the synergistic effect of adsorption-advanced oxidation and significantly improves efficiency of advanced oxidation. More importantly, the CNTs/FeS catalyst exhibit good regeneration performance and retains a high catalytic capacity (>75%) even after four reaction cycles. The catalytic mechanism were also studied further, the removal mechanism of ciprofloxacin by a CNTs/FeS heterogeneous Fenton-like process primarily involves three removal pathways occurring simultaneously: (a) adsorption removal by CNTs, (b) Fenton-like degradation catalyzed by FeS, (c) catalytic degradation by CNTs catalyst. And these actions also have synergistic effects for ciprofloxacin removal. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Recent Advances in Solid Catalysts Obtained by Metalloporphyrins Immobilization on Layered Anionic Exchangers: A Short Review and Some New Catalytic Results

    Shirley Nakagaki


    Full Text Available Layered materials are a very interesting class of compounds obtained by stacking of two-dimensional layers along the basal axis. A remarkable property of these materials is their capacity to interact with a variety of chemical species, irrespective of their charge (neutral, cationic or anionic. These species can be grafted onto the surface of the layered materials or intercalated between the layers, to expand or contract the interlayer distance. Metalloporphyrins, which are typically soluble oxidation catalysts, are examples of molecules that can interact with layered materials. This work presents a short review of the studies involving metalloporphyrin immobilization on two different anionic exchangers, Layered Double Hydroxides (LDHs and Layered Hydroxide Salts (LHSs, published over the past year. After immobilization of anionic porphyrins, the resulting solids behave as reusable catalysts for heterogeneous oxidation processes. Although a large number of publications involving metalloporphyrin immobilization on LDHs exist, only a few papers have dealt with LHSs as supports, so metalloporphyrins immobilized on LHSs represent a new and promising research field. This work also describes new results on an anionic manganese porphyrin (MnP immobilized on Mg/Al-LDH solids with different nominal Mg/Al molar ratios (2:1, 3:1 and 4:1 and intercalated with different anions (CO32− or NO3−. The influence of the support composition on the MnP immobilization rates and the catalytic performance of the resulting solid in cyclooctene oxidation reactions will be reported.

  12. Rapid determination of strontium-90 by solid phase extraction using DGA Resin® for seawater monitoring

    Tazoe, H.; Obata, H.; Yamagata, T.; Karube, Z.; Yamada, M.


    Strontium-90 concentrations in seawater exceeding the background level have been observed at the accidents of nuclear facilities, such as Chernobyl and Fukushima. However, analytical procedure for strontium-90 in seawater is still quite complicated and challenging. Here we show a simple and rapid analytical technique for the determination of strontium-90 in seawater samples without time-consuming separation of strontium from calcium. The separation with DGA Resin® is used to determine the abundance of strontium-90, which selectively collects yttrium-90, progeny of strontium-90. Naturally occurring radioactive nuclides (such as potassium, lead, bismuth, uranium, and thorium) and anthropogenic radionuclides (such as cesium, barium, lanthanum, and cerium) were separated from yttrium. Through a sample separation procedure, a high chemical yield of yttrium-90 was achieved at 93.9 % for seawater. The result of IAEA 443 certified seawater analysis was in good agreement with the certified value. At 20 hrs counting a lower detection limit of 1.5 mBq L-1 was obtained from 3 L of seawater. The proposed method can finish analyzing 8 samples per day, which is a reasonably fast throughput in actual seawater monitoring. Reproducibility was found to be 3.4 % according to 10 separate analyses of natural seawater samples from the vicinity of Fukushima Daiichi Nuclear Power Plant in September 2013.

  13. Nano-TiCl4/SiO2: An efficient heterogeneous solid acid catalyst for the one pot cascade five-component synthesis of densely functionalized tetrahydropyridines

    Abdolhamid Bamoniri; Bi Bi Fatemeh Mirjalili; Reza Tarazian


    Nano-TiCl4/SiO2 was found to be an inexpensive and efficient heterogeneous solid acid catalyst for the synthesis of one-pot cascade synthesis of highly functionalized asymmetric tetrahydropyridines from the five-component condensation reaction of the para-substituted anilines and aromatic aldehydes with ethyl acetoacetate under thermal conditions. Novel methodology, environmentally benign conditions, clean protocol, easy work-up and high yields are the important advantages of this protocol. The products were characterized using physical and spectroscopic data such as FT-IR, 1H-NMR and in some cases 13C-NMR and CHN analysis.

  14. Bamboo-type carbon nanotube solids derived from low-cost epoxy resins and their potential application for air filtration

    Keller, Teddy M.; Laskoski, Matthew; Long, Jeffrey W.; Qadri, Syed B.; Peterson, Gregory W.


    Carbon nanotubes (CNTs) are formed in bulk solids from the thermal decomposition of catalytic amounts of Fe2(CO)9 or Co2(CO)8 in the presence of an excess amount of a novolac epoxy carbon precursor during the conversion to a shaped thermoset composition and pyrolysis to 1,000 °C. The as-pyrolyzed carbonaceous solid is composed of either Fe or Co nanoparticles embedded in the nanostructured carbon, which contains bamboo-type carbon nanotubes, MWNTs, and some amorphous carbon. The Fe and Co nanoparticles, formed in situ from thermal decomposition of the corresponding salts, are responsible for the formation of the CNTs. The amorphous carbon is removed by selective combustion leaving a high surface area, porous composition. The pore network facilitates the transport of gaseous molecules such as ammonia to the adsorptive sites at the CNT surface and at entrained Fe or Co nanoparticle sites. During the combustion, the Fe and Co nanoparticles are oxidized to the corresponding nanostructured oxides, which are more receptive to ammonia absorption relative to the reduced metal. The ability to produce nanostructured solid compositions containing CNTs in any shape or form from inexpensive, commercially available carbon precursors is facilitating the development for application such as energy, gas sorption, chemical sensor, membrane, and nanodevices.

  15. One-pot Green Synthesis of Pyrrole Derivatives Catalyzed by Nano Sulfated Zirconia as a Solid Acid Catalyst%One-pot Green Synthesis of Pyrrole Derivatives Catalyzed by Nano Sulfated Zirconia as a Solid Acid Catalyst

    Teimouri, Abbas; Chermahini, Alireza Najafi


    A new and efficient method for the preparation of N-substituted pyrroles from one-pot Paal-Knorr condensation has been accomplished using nano-crystalline sulfated zirconia (SZ) as the catalyst in ethanol at moderate temperature. This new protocol has the advantages of easy availability, stability, reusability and eco-friendliness of the catalyst, high to excellent yields, simple experimental and work-up procedure. The synthesized compounds were confirmed through spectral characterization using IR, 1H NMR, 13C NMR and mass spectra.

  16. Steam Reforming of Dimethyl Ether over Coupled Catalysts of CuO-ZnO-Al2O3-ZrO2 and Solid-acid Catalyst%二甲醚水蒸气重整制氢CuO-ZnO-Al2O3-ZrO2/固体酸复合催化剂

    冯冬梅; 左宜赞; 王德峥; 王金福


    Steam reforming (SR) of dimethyl ether (DME) was investigated for the production of hydrogen for fuel cells. The activity of a series of solid acids for DME hydrolysis was investigated. The solid acid catalysts were ZSM-5[Si/Al= 25, 38 and 50: denoted Z(Si/Al)] and acidic alumina (γ-Al2O3) with an acid strength order that was Z(25)>Z(38)>Z(50)>γ-Al2O3. Stronger acidity gave higher DME hydrolysis conversion. Physical mixtures containing a CuO-ZnO-Zl2O3-ZrO2 catalyst and solid acid catalyst to couple DME hydrolysis and methanol SR were used to examine the acidity effects on DME SR. DME SR activity strongly depended on the activity for DME hydrolysis. Z(25) was the best solid acid catalyst for DME SR and gave a DME conversion>90% [T= 240℃,n(H2O)/n(DME) = 3.5, space velocity = 1179 ml·(g cat) -1·h-1, and P= 0.1MPa]. The influences of the reaction temperature, space velocity and feed molar ratio were studied. Hydrogen production significantly depended on temperature and space velocity. A bifunctional catalyst of CuO-ZnO-Al2O3-ZrO2 catalyst and ZSM-5 gave a high H2 production rate and CO2 selectivity.

  17. 超声波辅助固体酸催化塔尔油脂肪酸制备生物柴油%Preparation of biodiesel by ultrasonic assisted esterification of Tall oil fatty acid over solid acid catalyst

    林炎平; 陈学榕; 黎邵华; 廖燕华; 黄彪


    将强酸性阳离子交换树脂加入塔尔油脂肪酸和甲醇混合液中,并在超声波辐射辅助下得到生物柴油,对生物柴油的制备工艺和性能进行研究,同时建立动力学模型.结果表明,超声波辐射的辅助强化,能有效提高生物柴油的得率;在反应温度65℃、反应时间1h、甲醇与TOFA摩尔比为10∶1、脱水剂用量为TOFA6%、树脂NKC-9用量为TOFA40%的最佳工艺条件下,反应平衡常数可达11.18,生物柴油得率为90.0%.建立的动力学模型补充了超声波辐射辅助酯化反应动力学参数,并用此模型解释了各工艺参数呈现的规律.以廉价的制浆黑液回收物塔尔油脂肪酸为原料制备生物柴油,能有效地降低生物柴油价格,提高其市场竞争力,实现塔尔油高附加值利用,具有良好的发展前景.%Biodiesel was prepared by the esterification of Tall oil fatty acid (TOFA) with methanol over the cation exchange resin solid acid catalyst under the assistance of ultrasonic. The preparation process and the characteristic of the biodiesel obtained were investigated; a kinetic model was built. The results showed that the ultrasonic irradiation can effectively improve the yield of biodiesel. The optimum processing condition is 65 t, reaction time of 1 h, mol ratio of methanol/TOFA being 10, dehydrating agent quantity of 6% (based on TOFA) and catalyst amount of 40% (based on TOFA); under such a condition, the biodiesel yield reaches 90.0%. The kinetic parameters for the ultrasonic assisted esterification are obtained, which can well explain process regulation. Current process is economical to prepare biodiesel on the market, because cheap TOFA from black liquor is used as the raw material; it may provide a potential way to efficiently utilize TOFA.

  18. Esterification of Waste Frying Oil Using Styrene Type Cation Exchange Resin Catalyst%苯乙烯型阳离子交换树脂催化废煎炸油的酯化反应

    吕鹏梅; 刘莉梅; 杨玲梅; 袁振宏; 陈子博


    Porous polystyrene-divinylbenzene was prepared by suspension polymerization,and then sulfonie acid ion exchange resin was obtained by sulfonated porous polystyrene-divinylbenzene.The resin' s morphology and degree of sulfonation were characterized with SEM/EDS,BET,IR respectively.Esterification of waste frying oils with acid value of 63.0 mg/g was studied using cation exchange resin as catalyst to investigate its catalytic activity.40.0% dosage of porogen was preferred when the polymerization conditions were 360 r/min,1.0% dispersant,1.0% initiator,75℃ for 4 h and the heat to 85 ℃ for 6 h,while the sulfonation conditions were 1.0 mL/g dichloroethane,5.0 mL/g sulfuric acid,70℃ sulfonated for 1 h and the heat to 80 ~ 85℃ for 3 h,the optimum swelling time was 1 h,and the concentration of sulfuric acid was 98%.The maximum exchange capacity of the cation exchange resin W2 was 5.2 mmol/g in that condition.When the esterification was performed in the condition of 40.0% methanol,10.0% W2,70℃ stirring.for 1.5 h,the crushing rate of W2 was only 10.0% and the conversion rate of FFA reached to 86.8%.W2 is better than commercially available cation exchange resin PC101,and could be reused for 5 times.%以液体石蜡、邻苯二甲酸二丁酯为混合致孔剂,采用悬浮聚合法制备多孔聚苯乙烯-二乙烯苯,磺化后得到磺酸型阳离子交换树脂.利用SEM/EDS、BET、IR等手段对其形貌、磺化程度进行表征,并通过酸值为63.0 mg/g(以KOH计)煎炸油的酯化反应考察催化剂的活性.结果表明:磺酸根基团成功接到PS分子链上;在聚合条件为360 r/min、1.0%分散剂、1.0%引发剂、75℃保温4h、升温至85℃保温6h时,混合致孔剂的最佳添加量为40.0%液体石蜡、50.0%邻苯二甲酸二丁酯;在磺化条件为二氯乙烷1.0 mL/g、硫酸5.0 mL/g、70℃磺化1h后升温至80~85℃磺化3h时的最佳溶胀时间为1h、硫酸体积分数98%,

  19. 4-Amino-l,2,4-triazole Resin-supported Palladium Complex as Phosphine-free Catalyst for Suzuki Reaction in Aqueous Phase

    WU Xiang-mei; WANG Yan; GUO Sheng-rong


    @@ 1 Introduction The Suzuki cross-coupling reaction is a powerful and versatile method for the generation of unsymme-trical biaryls from arylboronic acids and aryl halides in a single step~([1-3]).However,the reaction is usually performed in the presence of Pd catalyst along with phosphine ligand,which sometimes creates practical problems because organophosphines tend to be expensive,poisonous,and air sensitive.Recently,phosphine-free ligands,such as nitrogen or sulfur-containing ligands~([4-6]) and N-heterocyclic car-benes~([7-12]) have been applied in Suzuki reaction effectively.

  20. Esterification of bio-oil from mallee (Eucalyptus loxophleba ssp. gratiae) leaves with a solid acid catalyst: Conversion of the cyclic ether and terpenoids into hydrocarbons.

    Hu, Xun; Gunawan, Richard; Mourant, Daniel; Wang, Yi; Lievens, Caroline; Chaiwat, Weerawut; Wu, Liping; Li, Chun-Zhu


    Bio-oil from pyrolysis of mallee (Eucalyptus loxophleba ssp. gratiae) leaves differs from that obtained with wood by its content of cyclic ethers, terpenoids and N-containing organic compounds. Upgrading of the leaf bio-oil in methanol with a solid acid catalyst was investigated and it was found that the N-containing organics in the bio-oil lead to deactivation of the catalyst in the initial stage of exposure and have to be removed via employing high catalyst loading to allow the occurrence of other acid-catalysed reactions. Eucalyptol, the main cyclic ether in the bio-oil, could be converted into the aromatic hydrocarbon, p-cymene, through a series of intermediates including α-terpineol, terpinolene, and α-terpinene. Various steps such as ring-opening, dehydration, isomerisation, and aromatization were involved in the conversion of eucalyptol. The terpenoids in bio-oil could also be converted into aromatic hydrocarbons that can serve as starting materials for the synthesis of fine chemicals, via the similar processes.

  1. Hydrogen Production from Water by Photolysis, Sonolysis and Sonophotolysis with Solid Solutions of Rare Earth, Gallium and Indium Oxides as Heterogeneous Catalysts

    Marta Penconi


    Full Text Available In this work, we present the hydrogen production by photolysis, sonolysis and sonophotolysis of water in the presence of newly synthesized solid solutions of rare earth, gallium and indium oxides playing as catalysts. From the experiments of photolysis, we found that the best photocatalyst is the solid solution Y0.8Ga0.2InO3 doped by sulphur atoms. In experiments of sonolysis, we optimized the rate of hydrogen production by changing the amount of water, adding ethanol and tuning the power of our piezoelectric transducer. Finally, we performed sonolysis and sonophotolysis experiments in the presence of S:Y0.8Ga0.2InO3 finding a promising synergistic effect of UV-visible electromagnetic waves and 38 kHz ultrasound waves in producing H2.

  2. Water-compatible dummy molecularly imprinted resin prepared in aqueous solution for green miniaturized solid-phase extraction of plant growth regulators.

    Wang, Mingyu; Chang, Xiaochen; Wu, Xingyu; Yan, Hongyuan; Qiao, Fengxia


    A water-compatible dummy molecularly imprinted resin (MIR) was synthesized in water using melamine, urea, and formaldehyde as hydrophilic monomers of co-polycondensation. A triblock copolymer (PEO-PPO-PEO, P123) was used as porogen to dredge the network structure of MIR, and N-(1-naphthyl) ethylenediamine dihydrochloride, which has similar shape and size to the target analytes, was the dummy template of molecular imprinting. The obtained MIR was used as the adsorbent in a green miniaturized solid-phase extraction (MIR⬜mini-SPE) of plant growth regulators, and there was no organic solvent used in the entire MIR⬜mini-SPE procedure. The calibration linearity of MIR⬜mini-SPE⬜HPLC method was obtained in a range 5⬜250ngmL(↙1) for IAA, IPA, IBA, and NAA with correlation coefficient (r) Ⱕ0.9998. Recoveries at three spike levels are in the range of 87.6⬜100.0% for coconut juice with relative standard deviations Ⱔ8.1%. The MIR⬜mini-SPE method possesses the advantages of environmental friendliness, simple operation, and high efficiency, so it is potential to apply the green pretreatment strategy to extraction of trace analytes in aqueous samples.

  3. Glyoxal-Urea-Formaldehyde Molecularly Imprinted Resin as Pipette Tip Solid-Phase Extraction Adsorbent for Selective Screening of Organochlorine Pesticides in Spinach.

    Yang, Chen; Lv, Tianwei; Yan, Hongyuan; Wu, Gaochan; Li, Haonan


    A new kind of glyoxal-urea-formaldehyde molecularly imprinted resin (GUF-MIR) was synthesized by a glyoxal-urea-formaldehyde (GUF) gel imprinting method with 4,4'-dichlorobenzhydrol as a dummy template. The obtained GUF-MIR was characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) and applied as a selective adsorbent of miniaturized pipet tip solid-phase extraction (PT-SPE) for the separation and extraction of three organochlorine pesticides (dicofol (DCF), dichlorodiphenyl dichloroethane (DDD), and tetradifon) in spinach samples. The proposed pretreatment procedures of spinach samples involved only 5.0 mg of GUF-MIR, 0.7 mL of MeOH-H2O (1:1, v/v) (washing solvent), and 0.6 mL of cyclohexane-ethyl acetate (9:1, v/v) (elution solvent). In comparison with other adsorbents (such as silica gel, C18, NH2-silica gel, and neutral alumina (Al2O3-N)), GUF-MIR showed higher adsorption and purification capacity for DCF, DDD, and tetradifon in aqueous solution. The average recoveries at three spiked levels ranged from 89.1% to 101.9% with relative standard deviations (RSDs) ≤ 7.1% (n = 3). The presented GUF-MIR-PT-SPE method combines the advantages of molecularly imprinted polymers (MIPs), GUF, and PT-SPE and can be used in polar solutions with high affinity and selectivity to the analytes in complex samples.

  4. Matrix effect on leaching of Bisphenol A diglycidyl ether (BADGE) from epoxy resin based inner lacquer of aluminium tubes into semi-solid dosage forms.

    Lipke, Uwe; Haverkamp, Jan Boris; Zapf, Thomas; Lipperheide, Cornelia


    To study the impact of different semi-solid dosage form components on the leaching of Bisphenol A (BPA) and Bisphenol A diglycidyl ether (BADGE) from the epoxy resin-based inner lacquer of aluminium tubes, the tubes were filled with different matrix preparations and stored at an elevated temperature. Despite compliance with the European Standards EN 15348 and EN 15766 on porosity and polymerisation of internal coatings of aluminium tubes, the commercially available tubes used in the study contained an increased amount of polymerisation residues, such as unbound BPA, BADGE and BADGE derivatives in the lacquer, as determined by acetonitrile extraction. Storage of Macrogol ointments in these tubes resulted in an almost quantitative migration of the unbound polymerisation residues from the coating into the ointment. In addition, due to alterations observed in the RP-HPLC chromatograms of the matrix spiked with BADGE and BADGE derivatives it is supposed that the leachates can react with formulation components. The contamination of the medicinal product by BPA, BADGE and BADGE derivatives can be precluded by using aluminium tubes with an internal lacquer with a low degree of unbound polymerisation residues. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  5. Determination of organophosphorus pesticides in ecological textiles by solid-phase microextraction with a siloxane-modified polyurethane acrylic resin fiber.

    Hu, Xianlei; Zhang, Mingqiu; Ruan, Wenhong; Zhu, Fang; Ouyang, Gangfeng


    A novel solid-phase microextraction (SPME) fiber coating was prepared with siloxane-modified polyurethane acrylic resin by photo-cured technology. The ratio of two monomers was investigated to obtain good microphase separation structure and better extraction performance. The self-made fiber was then applied to organophosphorus pesticides (OPPs) analysis and several factors, such as extraction/desorption time, extraction temperature, salinity, and pH, were studied. The optimized conditions were: 15 min extraction at 25 °C, 5% Na(2)SO(4) content, pH 7.0 and 4 min desorption in GC inlet. The self-made fiber coating exhibited better extraction efficiency for OPPs, compared with three commercial fiber coatings. Under the optimized conditions, the detection limits of 11 OPPs were from 0.03 μg L(-1) to 0.5 μg L(-1). Good recoveries and repeatabilities were obtained when the method was used to determine OPPs in ecological textile.

  6. Determination of copper, lead and iron in water and food samples after column solid phase extraction using 1-phenylthiosemicarbazide on Dowex Optipore L-493 resin.

    Yildiz, Ozden; Citak, Demirhan; Tuzen, Mustafa; Soylak, Mustafa


    A novel solid phase extraction procedure for determination of copper, lead and iron in natural water and food samples has been established in the presented work. 1-Phenylthiosemicarbazide (1-PTSC) as ligand and Dowex Optipore L-493 resin as adsorbent were used in a mini chromatographic column. Various analytical conditions for the quantitative recoveries of analyte ions including pH, amounts of adsorbent, eluent, sample volume, etc. were investigated. The recovery values for analyte ions were higher than 95%. The determination of copper, lead and iron was performed by flame atomic absorption spectrometry. The influences of some alkali, alkali earth and transition metals on the recoveries of analyte ions were investigated. The preconcentration factor was 62.5. The limit of detections of the understudied analytes (k=3, N=21) were 0.64 μg L(-1) for copper, 0.55 μg L(-1) for lead and 0.82 μg L(-1) for iron. The relative standard deviation was found to be lower than 6%. The accuracy of the method was confirmed with certified reference material (GBW 07605 Tea). The method was successively applied for the determination of copper, lead and iron in water and some food samples including cheese, bread, baby food, pekmez, honey, milk and red wine after microwave digestion.

  7. Microwave-assisted solid-phase peptide synthesis of the 60-110 domain of human pleiotrophin on 2-chlorotrityl resin.

    Friligou, Irene; Papadimitriou, Evangelia; Gatos, Dimitrios; Matsoukas, John; Tselios, Theodore


    A fast and efficient microwave-assisted solid phase peptide synthesis (MW-SPPS) of a 51mer peptide, the main heparin-binding site (60-110) of human pleiotrophin (hPTN), using 2-chlorotrityl chloride resin (CLTR-Cl) following the 9-fluorenylmethyloxycarbonyl/tert-butyl (Fmoc/tBu) methodology and with the standard N,N'-diisopropylcarbodiimide/1-hydroxybenzotriazole (DIC/HOBt) coupling reagents, is described. An MW-SPPS protocol was for the first time successfully applied to the acid labile CLTR-Cl for the faster synthesis of long peptides (51mer peptide) and with an enhanced purity in comparison to conventional SPPS protocols. The synthesis of such long peptides is not trivial and it is generally achieved by recombinant techniques. The desired linear peptide was obtained in only 30 h of total processing time and in 51% crude yield, in which 60% was the purified product obtained with 99.4% purity. The synthesized peptide was purified by reversed phase high performance liquid chromatography (RP-HPLC) and identified by electrospray ionization mass spectrometry (ESI-MS). Then, the regioselective formation of the two disulfide bridges of hPTN 60-110 was successfully achieved by a two-step procedure, involving an oxidative folding step in dimethylsulfoxide (DMSO) to form the Cys(77)-Cys(109) bond, followed by iodine oxidation to form the Cys(67)-Cys(99) bond.

  8. Two-dimensional near-infrared photonic crystal fabrication by generation of void channels in solid resin

    Guangyong Zhou; Michael James Ventura; Min Gu


    Two-dimensional (2D) triangular void channel photonic crystals with different lattice constants stacked in two different directions were fabricated by using femtosecond laser micro-explosion in solid polymer material. Fundamental and higher-order stop gaps were observed both in the infrared transmission and reflection spectra. There is an approximately linear relationship between the gap position and the lattice constant. The suppression of the fundamental gap is as high as 70% for 24-layer structures stacked in the Г-M direction.

  9. Extration liquede -solide du ZN (II) en mileu acetate par des resines amberlites type xad impregnees dextractantzs organophsphores.


    Léxtraction solide-liquide est largeinent utilisée dans le domaine de l'hydrométallurgie et dans le traitement des eaux contaminées du fait de sa simplicité de mise en oeuvre.ainsi de la facilite de régénérer les résines. Notre travail porte sur l'extraction du Zn(ll) acétate par des résines de type Amberlite (AXD, XAD4, XAD7, XAD1180).

  10. Catalyst in Basic Oleochemicals

    Eva Suyenty


    Full Text Available Currently Indonesia is the world largest palm oil producer with production volume reaching 16 million tones per annum. The high crude oil and ethylene prices in the last 3 – 4 years contribute to the healthy demand growth for basic oleochemicals: fatty acids and fatty alcohols. Oleochemicals are starting to replace crude oil derived products in various applications. As widely practiced in petrochemical industry, catalyst plays a very important role in the production of basic oleochemicals. Catalytic reactions are abound in the production of oleochemicals: Nickel based catalysts are used in the hydrogenation of unsaturated fatty acids; sodium methylate catalyst in the transesterification of triglycerides; sulfonic based polystyrene resin catalyst in esterification of fatty acids; and copper chromite/copper zinc catalyst in the high pressure hydrogenation of methyl esters or fatty acids to produce fatty alcohols. To maintain long catalyst life, it is crucial to ensure the absence of catalyst poisons and inhibitors in the feed. The preparation methods of nickel and copper chromite catalysts are as follows: precipitation, filtration, drying, and calcinations. Sodium methylate is derived from direct reaction of sodium metal and methanol under inert gas. The sulfonic based polystyrene resin is derived from sulfonation of polystyrene crosslinked with di-vinyl-benzene. © 2007 BCREC UNDIP. All rights reserved.[Presented at Symposium and Congress of MKICS 2007, 18-19 April 2007, Semarang, Indonesia][How to Cite: E. Suyenty, H. Sentosa, M. Agustine, S. Anwar, A. Lie, E. Sutanto. (2007. Catalyst in Basic Oleochemicals. Bulletin of Chemical Reaction Engineering and Catalysis, 2 (2-3: 22-31.  doi:10.9767/bcrec.2.2-3.6.22-31][How to Link/DOI: || or local:

  11. Production of biodiesel from palm fatty acid distillate using sulfonated-glucose solid acid catalyst:Characterization and optimization

    Ibrahim M Lokman; Umer Rashid; Yun Hin Taufiq-Yap


    A palm fatty acid distillate (PFAD) has been used for biodiesel production. An efficient sulfonated-glucose acid catalyst (SGAC) was prepared by sulfonation to catalyze the esterification reaction. The effect of three variables i.e. methanol-to-PFAD molar ratio, catalyst amount and reaction time, on the yield of PFAD esters was studied by the response surface methodology (RSM). The optimum reaction conditions were:12.2:1 methanol-to-PFAD molar ratio, 2.9%catalyst concentration and 134 min of time as predicted by the RSM. The reaction under the optimum conditions resulted in 94.5%of the free fatty acid (FFA) conversion with 92.4%of the FAME yield. The properties of the PFAD esters were determined according to biodiesel standards.

  12. 固体碱负载Ru催化山梨醇氢解制备低碳二元醇%Solid base supported Ru catalysts for sorbitol hydrogenolysis

    周静红; 王雪峰; 刘国才; 隋志军; 周兴贵; 袁渭康


    Hydrogenolysis of biomass-derived sorbitol into ethylene and propylene glycols, an alternative route for petroleum based process, usually takes place over metal catalyst with a base promoter. The presence of soluble bases introduces additional problems for their separation and recovery, increasing the complexity and operating cost of the process. Sometimes, these base additives result in the formation of more side-products. Ru supported on various solid bases to facilitate catalyst recovery and recycle was investigated. Ru catalysts supported on 2 solid bases, hydrotalcite (HT) and hydroxyapatite, were prepared and investigated for sorbitol hydrogenolysis activity in base-free aqueous solution, and their performance was compared with that of Ru catalyst supported on carbon nanofibers (Ru/CNFs), with and without promotion by CaO. The physico-chemical properties of both supports and the supported Ru catalysts were characterized by SEM, N2 physisorption, XRD, TEM and CO2-TPD. The results indicate that Ru particles well disperse on the basic support and show as good activity as Ru/CNFs catalysts in sorbitol hydrogenolysis. The Ru catalyst using HT calcined at 500°C as a support shows the best catalytic performance with promoted sorbitol conversion, higher selectivity to desired glycols and fewer byproducts. As a result, Ru/HT is believed to be a promising catalyst for sorbitol hydrogenolysis without added base. This is relevant to the development of a green process to produce glycols from biomass.%采用羟基磷灰石和镁铝水滑石两种固体碱为载体制备了Ru催化剂,通过N2物理吸附、扫描电子显微镜、高分辨透射显微镜、X 射线衍射分析表征了形貌和物理化学性能,并与纳米碳纤维负载的Ru催化剂(Ru/CNFs)在无碱促进剂及有碱促进剂存在下催化山梨醇氢解制备二元醇的活性进行了比较。结果表明,固体碱负载的 Ru催化剂,在无碱促进剂的条件下在山

  13. Latent catalyst; Senzaisei shokubai



    Epoxy resin, an important function material to support such main industries as electric and electronic devices, automobiles, civil engineering, and building construction, is demanded of development of single liquid type resin having excellent quick hardening performance and storage stability. This requirement comes from environmental problems with an intention of saving energies and reducing resin wastes. The Company, using freely its independent phase separation technology that controls molecular structure of catalysts, developed a latent catalyst having excellent storage stability and high-temperature quick hardening performance. Its major features may be summarized as follows: (1) excellent storage stability at room temperature keeping the product stable for 2.5 months or longer (2 days in conventional products); (2) quick hardening performance hardening the resin in seven seconds at 150 degrees C (equivalent to conventional products); and (3) excellent insulation performance of hardened resin at 140 degrees C of 7 times 10 {sup 13} (ohm) (center dot) cm (2 times 10 {sup 12} (ohm) (center dot) cm in conventional products) (translated by NEDO)

  14. Hydroxyapatite supported caesium carbonate as a new recyclable solid base catalyst for the Knoevenagel condensation in water

    Monika Gupta


    Full Text Available The Knoevenagel condensation between aromatic aldehydes and malononitrile, ethyl cyanoacetate or malonic acid with hydroxyapatite supported caesium carbonate in water is described. HAP–Cs2CO3 was found to be a highly active, stable and recyclable catalyst under the reaction conditions.

  15. PEG-related polymer resins as synthetic supports


    Combinatorial chemistry has become a significant part of the discovery and optimization process for novel drugs,affinity ligands,and catalysts.The polymeric supports play a key role in combinatory chemistry.Therefore,various kinds of functional polymer resins have been exploited as supports,reagents,and catalysts in organic synthesis.In comparison to the conventional Merrifield resins,the poly(ethylene glycol)(PEG)-related polymer resins have advantages including good compatibilities with polar solvents,good solvent absorbency and swelling properties.This review focuses primarily on the more recent work in the field of developing PEG-related polymer resins as supports for organic synthesis.

  16. The Deactivation Mechanism and Regeneration Methods of Resin Catalyst for the Esterification of Camphene%莰烯酯化制乙酸异龙脑酯催化剂失活机理及再生方法的研究

    屈艳艳; 郑辉东; 邹文虎; 王莹淑; 吴燕翔


    通过BET、FT-IR、元素分析、SEM、N2低温吸附、离子交换容量测定等表征手段对莰烯酯化制备乙酸异龙脑酯固定床催化剂(CT800)失活机理及再生方法进行了研究.结果表明,催化剂活性降低的主要原因是反应过程中生成的聚合物对催化剂活性中心的覆盖造成的.通过乙醇浸取的方法对失活催化剂再生后,其酯化反应的活性接近新鲜催化剂水平,是一种较好的再生手段.%Cation exchange resin as catalyst for the preparation of isobornyl acetate by the esterification of camphene is widely used in industry. However this type of catalyst is easy to lose its activity during the reaction. In this paper, the deactivation mechanism and regeneration method of the catalyst ( CT800 ) were investigated. It showed that the deactivation of catalyst was mainly caused by the overlay of polymer byproducts on the resin activity centers. The deactivated catalyst can be regenerated by washing with ethanol. The activity of the regenerated catalyst is close to that of fresh one. This proves that this generation method is effective.

  17. Transesterification of vegetable oil to biodiesel using a heteropolyacid solid catalyst%固体杂多酸催化制备芸芥生物柴油

    柴芳; 曹凤华; 翟凤英; 陈阳; 王晓红; 苏忠民


    研制出清洁、环境友好的制备生物柴油的方法.以固体杂多酸Cs2.5H0.5PW12O40为非均相催化剂,芸芥植物油为原料,与甲醇进行酯交换反应制备生物柴油.考查了反应时间、反应温度、醇油摩尔比、催化剂用量及催化剂的使用次数对芸芥油转化率的影响.探究出制备生物柴油的最佳反应条件.与传统的均相催化剂(H2SO4、NaOH)相比,固体杂多酸Cs2.5H0.5PW12O40表现出相同的催化活性,并易于分离,可重复使用.而且杂多酸的催化活性不受芸芥油中游离脂肪酸和水含量的影响.可在短时间、低温(室温)条件下完成酯化反应.结果表明,耐水型Cs2.5H0.5PW12O40是制备生物柴油的环境友好型固体酸催化剂.芸芥生物柴油的各项指标符合美国生物柴油标准.%A clean,facile,ecologically friendly method of production of biodiesel has been developed.A solid acid,namely heteropolyacid(HPA)Cs2.5H0.5PW12O40 has been used as a heterogeneous catalyst for the production of biodiesel from Eruca Sativa Gars oils(ESG oil)with methanol at certain temperature.A study for optimizing the reaction conditions such as the reaction time,temperature,the oil to methanol ratio,the amount of catalyst,and the usage times of the catalyst,have been performed.The Cs2.5H0.5PW12O40 heterogeneous acid catalyst shows almost the same activity under the optimized reaction conditions compared to conventional homogeneous catalyst such as sodium hydroxide or sulfuric acid,and can easily be separated from the products and carl be used more times.The most important feature of this catalyst is that the catalytic activity is not effected by the content of free fatty acid and content of water in the vegetable oil and the esterification can occur at a lower temperature (room temperature) and be finished within a shorter time.The results illustrate that the Cs2.5H0.5PW12O40 is an excellent water-tolerant and environmentally benign solid acid catalyst for

  18. La-Sr-Ni-Co-O based perovskite-type solid solutions as catalyst precursors in the CO 2 reforming of methane

    Valderrama, Gustavo; Kiennemann, Alain; Goldwasser, Mireya R.

    La 1- xSr xNi 0.4Co 0.6O 3 and La 0.8Sr 0.2Ni 1- yCo yO 3 solid solutions with perovskite-type structure were synthesized by the sol-gel resin method and used as catalytic precursors in the dry reforming of methane with CO 2 to syngas, between 873 and 1073 K at atmospheric pressure under continuous flow of reactant gases with CH 4/CO 2 = 1 ratio. These quaternary oxides were characterized by X-ray diffraction (XRD), BET specific surface area and temperature-programmed reduction (TPR) techniques. XRD analyses of the more intense diffraction peaks and cell parameter measurements showed formation of La-Sr-Ni-Co-O solid solutions with La 0.9Sr 0.1CoO 3 and/or La 0.9Sr 0.1NiO 3 as the main crystallographic phases present on the solids depending on the degree of substitution. TPR analyses showed that Sr doping decreases the temperature of reduction via formation of intermediary species producing Ni 0, Co 0 with particle sizes in the range of nanometers over the SrO and La 2O 3 phases. These metallic nano particles highly dispersed in the solid matrix are responsible for the high activity shown during the reaction and avoid carbon formation. The presence of Sr in doping quantities also promotes the secondary reactions of carbon formation and water-gas shift in a very small extension during the dry reforming reaction.

  19. La-Sr-Ni-Co-O based perovskite-type solid solutions as catalyst precursors in the CO{sub 2} reforming of methane

    Valderrama, Gustavo [Laboratorio de Catalisis, Petroleo y Petroquimica, Unidad de Estudios Basicos, Universidad de Oriente - Nucleo Bolivar, La Sabanita - Calle San Simon, Estado Bolivar 8001 (Venezuela); Kiennemann, Alain [Laboratoire des Materiaux et Procedes pour la Catalyse, UMR 7515, ECPM, Universite Louis Pasteur, 25 rue Becquerel, 67087 Strasbourg Cedex 2 (France); Goldwasser, Mireya R. [Centro de Catalisis, Petroleo y Petroquimica, Facultad de Ciencias - Universidad Central de Venezuela. Paseo los Ilustres, Los Chaguaramos, Caracas 1040 (Venezuela)


    La{sub 1-x}Sr{sub x}Ni{sub 0.4}Co{sub 0.6}O{sub 3} and La{sub 0.8}Sr{sub 0.2}Ni{sub 1-y}Co{sub y}O{sub 3} solid solutions with perovskite-type structure were synthesized by the sol-gel resin method and used as catalytic precursors in the dry reforming of methane with CO{sub 2} to syngas, between 873 and 1073 K at atmospheric pressure under continuous flow of reactant gases with CH{sub 4}/CO{sub 2} = 1 ratio. These quaternary oxides were characterized by X-ray diffraction (XRD), BET specific surface area and temperature-programmed reduction (TPR) techniques. XRD analyses of the more intense diffraction peaks and cell parameter measurements showed formation of La-Sr-Ni-Co-O solid solutions with La{sub 0.9}Sr{sub 0.1}CoO{sub 3} and/or La{sub 0.9}Sr{sub 0.1}NiO{sub 3} as the main crystallographic phases present on the solids depending on the degree of substitution. TPR analyses showed that Sr doping decreases the temperature of reduction via formation of intermediary species producing Ni{sup 0}, Co{sup 0} with particle sizes in the range of nanometers over the SrO and La{sub 2}O{sub 3} phases. These metallic nano particles highly dispersed in the solid matrix are responsible for the high activity shown during the reaction and avoid carbon formation. The presence of Sr in doping quantities also promotes the secondary reactions of carbon formation and water-gas shift in a very small extension during the dry reforming reaction. (author)

  20. Preparation and properties of hydroxyl functionalized star acrylic resin for high solid coating%高固体分涂料用含羟基星形丙烯酸酯树脂的制备及性能

    任强; 黄春燕; 周琳楠; 李坚; 汪称意; 邓健; 方建波


    以占单体物质的量0.01%的低铜盐用量催化剂体系进行电子转移活化再生催化剂原子转移自由基聚合(ARGET ATRP),制备了丙烯酸丁酯、甲基丙烯酸甲酯和丙烯酸羟丙酯为单体的线形和六臂星形共聚物。采用折光指数-激光-黏度三检测联用GPC,1H NMR和DSC对聚合物的分子结构、共聚组成和玻璃化转变行为进行了研究。将聚合物配制成涂料用树脂溶液,流变行为研究表明星形聚合物溶液黏度最低。在高固含量时,星形聚合物降低黏度的优势更明显。在适合喷涂施工的黏度下,六臂星形共聚物比普通自由基聚合得到的商品化丙烯酸酯树脂的固含量可提高10%。采用异氰酸酯固化剂固化得到的漆膜性能测试表明,星形聚合物对应清漆的表干时间很短,同时力学性能达到良好水平。%The copolymers of n-butyl acrylate, methyl methacrylate and 2-hydroxypropyl acrylate were prepared by activators regenerated by electron transfer atom transfer radical polymerization(ARGET ATRP)using the hexa-functional and mono-functional initiators and 0.01%low concentration of complex catalyst. The molecular structure, copolymer composition and glass transition behavior of the polymers were characterized by refractive index-multi angle laser light scattering-viscometer triple detection gel permeation chromatography, hydrogen proton nuclear resonance (1H NMR) and differential scanning calorimetry (DSC), respectively. The obtained polymers were formulated into solutions for coating. Rheology tests revealed that viscosity of star polymers was the lowest. The viscosity decreasing efficiency was more remarkable at high solids contents. Under suitable spray viscosity, the solid content of star copolymer increased by 10%compared with commercial acrylic resin obtained by conventional free radical polymerization. The tack-free time of varnish composed of star polymers and isocyanate curing agent was

  1. Investigation of the behaviour of solid acid catalysts for acylations and cyanisations of aromatics. Final report; Untersuchungen zur Wirkungsweise von festen sauren Katalysatoren bei Acylierungen und Cyanierungen von Aromaten. Abschlussbericht

    Kemnitz, E.


    The present state of the art in the field of FRIEDEL-CRAFTS-ACYLATIONS is characterized by the application of homogenous catalysts (at least stochiometric amounts) like AlCl{sub 3} or FeCl{sub 3}. Problems arising from this application are corrosions, difficult product separations from the catalyst and the origin of acid waste water. Hence, the aim of this project was the development of suitable solid catalysts which overcome the problems ascribed above. Sulfated zirconia (SZ) was found to be an excellent solid Br.o/nsted-acid to be used especially in their aerogel or cryogel form. Thus with this catalyst system, in the benzoylation of anisol nearly 100% conversion may be achieved. In this way it could be proved, that with SZ a solid Br.o/nsted-acid might be available which gives reasonable hope to substitute in a near future, at least for some reactions, the classical homogeneous catalysts and to overcome their problems in use. (orig.)

  2. Correlations between (51)V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts.

    Fenn, Annika; Wächtler, Maria; Gutmann, Torsten; Breitzke, Hergen; Buchholz, Axel; Lippold, Ines; Plass, Winfried; Buntkowsky, Gerd


    The parameters describing the quadrupolar and CSA interactions of 51V solid-state MAS NMR investigations of model complexes mimicking vanadoenzymes as well as vanadium containing catalysts and enzyme complexes are interpreted with respect to the chemical structure. The interpretation is based on the data of 15 vanadium complexes including two new complexes with previously unpublished data and 13 complexes with data previously published by us. Correlations between the chemical structure and the 51V solid-state NMR data of this class of compounds have been established. Especially for the isotropic chemical shift delta(iso) and the chemical shift anisotropy delta(sigma), correlations with specific structural features like the coordination number of the vanadium atom, the number of coordinating nitrogens, the number of oxygen atoms and the chemical surrounding of the complex could be established for these compounds. Moreover, quantitative correlations between the solid-state NMR parameters and specific bond angles and bond lengths have been obtained. Our results can be of particular interest for future investigations concerning the structure and the mode of action of related vanadoenzymes and vanadate protein assemblies, including the use of vanadate adducts as transition state analogs for phosphate metabolizing systems.

  3. 固体酸催化蓖麻油制备生物柴油%Preparation of biodiesel from castor seed oil using solid acid as a catalyst

    靳福全; 牛宇岚; 李晓红


    以一水硫酸氢钠固体酸为催化剂,对蓖麻油酯交换制备生物柴油进行了研究.在反应温度为75℃条件下,考察了醇油摩尔比、催化剂用量(占油质量)及反应时间对酯交换反应的影响.在反应温度为75℃、醇油摩尔比为9:1、催化剂用量为4%、反应时间为8 h的优化工艺条件下,平均甘油收率达93%,产物中甲酯总含量为95.20%.甲酯和甘油静置分层快,后处理简单,对环境无污染.%The transesterification of castor seed oil to produce biodiesel catalyzed by solid acid sodium bisulfate monohydrate was studied. At the temperature of 75 ℃, effects of molar ratio of methanol to oil, catalyst dosage ( mass ratio of catalyst to oil) and reaction time on the transesterification were investigated. Under the optimal conditions of reaction temperature 75 ℃, molar ratio of methanol to oil 9: 1, catalyst dosage 4% and reaction time 8 h, the average yield of glycerine arrived 93% . The products were analyzed by GC - MS and the mass fraction of methyl ester was 95.20%. The methyl ester and the glycerine were easily separated, and the method had no pollution to the environment.

  4. Curing Mechanism of Condensed Polynuclear Aromatic Resin and Thermal Stability of Cured Resin

    Li Shibin; Sun Qiqian; Wang Yuwei; Wu Mingbo; Zhang Zailong


    In order to improve the thermal stability of condensed polynuclear aromatic (COPNA) resin synthesized from vacuum residue, 1,4-benzenedimethanol was added to cure COPNA resin. The curing mechanism was investigated by pro-ton nuclear magnetic resonance spectrometry, solid carbon-13 nuclear magnetic resonance spectrometry and Fourier trans-form infrared spectroscopy. Microstructures of the uncured and the cured COPNA resins were studied by scanning electron microscopy and X-ray diffractometry. The thermal stability of COPNA resins before and after curing was tested by thermo-gravimetric analysis. The element composition of the cured COPNA resin heated at different temperatures was analyzed by an element analyzer. The results showed that the uncured COPNA resin reacted with the cross-linking agent during the cur-ing process, and the curing mechanism was conifrmed to be the electrophilic substitution reaction. Compared with the un-cured COPNA resin, the cured COPNA resin had a smooth surface, well-ordered and streamlined sheet structure with more crystalline solids, better molecular arrangement and orientation. The weight loss process of the uncured and cured COPNA resins was divided into three stages. Carbon residue of the cured COPNA resin was 41.65%at 600℃, which was much higher than 25.02%of the uncured COPNA resin, which indicated that the cured COPNA resin had higher thermal stability.

  5. Performance improvement of direct internal reforming solid oxide fuel cell fuelled by H2S-contaminated biogas with paper-structured catalyst technology

    Shiratori, Y.; Sakamoto, M.


    Direct internal reforming (DIR) operation of a solid oxide fuel cell (SOFC) is a very attractive concept for downsizing and cost reduction of SOFC systems. This study aimed to develop stable operation of a DIR-SOFC fuelled by biogas. The current-voltage (I-V) curves of 2 × 2 cm2 planar SOFCs (anode- and electrolyte-supported cells, ASC and ESC, respectively.) were measured at 800 °C in the direct feed of a simulated biogas mixture (CH4/CO2 = 1), and the flexible structured catalyst material (paper-structured catalyst (PSC)) was applied on the anode material for performance enhancement. By applying a hydrotalcite (HT)-dispersed PSC (HT-PSC), the sulfur tolerance of the SOFC in the DIR operation was remarkably improved. By the effect of the HT-PSC, for both ASC and ESC, a stable cell voltage higher than 800 mV was obtained over 200 h at 0.2 A cm-2 in the direct feed of simulated biogas under 5 ppm H2S poisoning.

  6. Synthesis and characterization of mesoporous Si-MCM-41 materials and their application as solid acid catalysts in some esterification reactions

    Tarun F Parangi; Rajesh M Patel; Uma V Chudasama


    Mesoporous MCM-41 has been synthesized by sol–gel method at room temperature possessing good thermal stability, high surface area as well as retention of surface area at high temperature. The MCM-41 neutral framework has been modified and put to practical use by incorporating Al3+ in the siliceous MCM-41 framework and supporting 12-TPA (12-tungstophosphoric acid) onto MCM-41 by process of anchoring and calcination to induce Brønsted acidity in MCM-41 to yield Al-MCM-41 and 12TPA-MCM-41, respectively. The synthesized materials have been characterized for elemental analysis by ICP-AES, XRD, SEM, TEM, EDX, FT–IR and TGA. Surface area has been determined by BET method and pore size and pore size distribution determined by BJH method. Surface acidity has been evaluated by NH3-TPD method. The potential use of Al-MCM-41 and 12TPA-MCM-41 as solid acid catalysts has been explored and compared by studying esterification as a model reaction wherein monoesters such as ethyl acetate (EA), propyl acetate (PA), butyl acetate (BA) and benzyl acetate (BzA) have been synthesized, optimizing several parameters such as catalyst amount, reaction time, reaction temperature and mole ratio of reagents.

  7. Superior performance of metal-organic frameworks over zeolites as solid acid catalysts in the Prins reaction: green synthesis of nopol.

    Opanasenko, Maksym; Dhakshinamoorthy, Amarajothi; Hwang, Young Kyu; Chang, Jong-San; Garcia, Hermenegildo; Čejka, Jiří


    The catalytic performance of a set of metal-organic frameworks [CuBTC, FeBTC, MIL-100(Fe), MIL-100(Cr), ZIF-8, MIL-53(Al)] was investigated in the Prins condensation of β-pinene with formaldehyde and compared with the catalytic behavior of conventional aluminosilicate zeolites BEA and FAU and titanosilicate zeolite MFI (TS-1). The activity of the investigated metal-organic frameworks (MOFs) increased with the increasing concentration of accessible Lewis acid sites in the order ZIF-8zeolites BEA and FAU, which showed significantly lower selectivity to the target nopol than the MOFs. Its high activity, the preservation of its structure and active sites, and the possibility to use it in at least three catalytic cycles without loss of activity make MIL-100 (Fe) the best performing catalyst of the series for the Prins condensation of β-pinene and paraformaldehyde. Our report exemplifies the advantages of MOFs over zeolites as solid catalysts in liquid-phase reactions for the production of fine chemicals.

  8. Influence of Ce0.35Zr0.55Y0.10 Solid Solution on Performance of Pt-Rh Three-Way Catalysts


    Ce0.35Zr0.55Y0.10 solid solution was prepared by co-precipitation technique and characterized by specific surface area measurements (BET) and X-ray diffraction (XRD). Ce0.35Zr0.55Y0.10 was used to prepare low Pt-Rh three-way catalyst (TWC), and its influence on the performance of TWC was investigated. The results revealed that Ce0.35Zr0.55Y0.10 had a cubic structure similar to Ce0.50Zr0.50O2 and its specific surface area can maintain higher than Ce0.50Zr0.50O2 after 1000 ℃ calcination for 5 h. Being hydrothermal aged at 1000 ℃ for 5 h, the catalyst containing Ce0.35Zr0.55Y0.10 still exhibited higher conversion of C3H8, CO and NO and lower light-off temperature in comparison with Ce0.50Zr0.50O2 TWC.

  9. Production of furfural from xylose, water-insoluble hemicelluloses and water-soluble fraction of corncob via a tin-loaded montmorillonite solid acid catalyst.

    Li, Huiling; Ren, Junli; Zhong, Linjie; Sun, Runcang; Liang, Lei


    The conversion of xylose, water-insoluble hemicelluloses (WIH) and water-soluble fraction (WSF) of corncob to furfural was performed using montmorillonite with tin ions (Sn-MMT) containing double acid sites as a solid acid catalyst. The co-existence of Lewis acids and Brønsted acids in Sn-MMT was shown to improve the furfural yield and selectivity. 76.79% furfural yield and 82.45% furfural selectivity were obtained from xylose using Sn-MMT as a catalyst in a biphasic system with 2-s-butylphenol (SBP) as the organic extracting layer and dimethyl sulfoxide (DMSO) as the co-solvent in contact with an aqueous phase saturated with NaCl (SBP/NaCl-DMSO) at 180°C for 30min. Furthermore, Sn-MMT also demonstrated the excellent catalytic performance in the conversion of pentose-rich materials of corncob and 39.56% and 54.15% furfural yields can be directly obtained from WIH and WSF in the SBP/NaCl-DMSO system, respectively.

  10. Epoxy resins.

    Bray, P G


    Epoxy resins have an extraordinarily broad range of commercial applications, especially as protective surface coatings and adhesives. Epoxy resin systems include combinations of epoxy monomers, hardeners, reactive diluents, and/or a vast array of other additives. As a result, an epoxy resin system may have a number of chemical ingredients with the potential for attendant health hazards. Most, but not all, of these health hazards arise in the occupational setting. The most frequent adverse effects are irritation or allergic mechanisms involving the dermal and respiratory systems. Sensitization usually is caused by low molecular weight or short-chain compounds. This review discusses the diagnosis, treatment, and prevention of epoxy resin-related adverse health effects.

  11. EP-toxicity test of saturated GT-73 resin and resin in grout

    Bibler, J.P.


    The results of EP-toxicity tests on mercury saturated Duolite{reg_sign} GT-73 cation exchange resin clarify options for the ultimate disposal of spent resin. Samples of GT-73 saturated with mercury passed the EP-toxicity test, indicating that fully spent resin may be classifed as ``solid``-not``hazardous``-waste and stored or disposed-of as such. Samples of GT-73 resin saturated with mercury and then incorporated into Portland Type 1 cement did not pass the EP-toxicity test and fall into the ``hazardous waste`` category. Samples of GT-73 resin less-than-saturated with mercury which were in corporated in Portland Type 1 cement passed the EP-toxicity test and may be classified as ``solid waste.`` Other commercially available materials are being investigated for incorporating fully spent GT-73 resin in a solid waste form.

  12. Periodic Mesoporous Organosilica Functionalized with Sulfonic Acid Groups as Acid Catalyst for Glycerol Acetylation

    Pascal Van Der Voort


    Full Text Available A Periodic Mesoporous Organosilica (PMO functionalized with sulfonic acid groups has been successfully synthesized via a sequence of post-synthetic modification steps of a trans-ethenylene bridged PMO material. The double bond is functionalized via a bromination and subsequent substitution obtaining a thiol functionality. This is followed by an oxidation towards a sulfonic acid group. After full characterization, the solid acid catalyst is used in the acetylation of glycerol. The catalytic reactivity and reusability of the sulfonic acid modified PMO material is investigated. The catalyst showed a catalytic activity and kinetics that are comparable with the commercially available resin, Amberlyst-15, and furthermore our catalyst can be recycled for several subsequent catalytic runs and retains its catalytic activity.

  13. Spatially resolved characterization of catalyst-coated membranes by distance-controlled scanning mass spectrometry utilizing catalytic methanol oxidation as gas-solid probe reaction.

    Li, Nan; Assmann, Jens; Schuhmann, Wolfgang; Muhler, Martin


    The spatially resolved catalytic activity of a catalyst-coated membrane (CCM), which is the essential part of PEM fuel cells, was visualized rapidly without any damage by a distance-controlled scanning mass spectrometer with an improved resolution of 250 microm. Methanol oxidation was identified as a suitable gas-solid probe reaction for the characterization of local catalytic activity. In addition, defects were manually generated in the CCM to simulate inhomogeneous coating and pinholes. The measurements successfully demonstrated that catalytically active and less active regions can be clearly distinguished. Simultaneously, the local topography was recorded, providing additional information on the location of the scratches and pinholes. The catalytic results were highly reproducible due to the constant-distance feedback loop rendering scanning mass spectrometry a promising tool for the quantitative quality control of CCMs.

  14. Immobilized Ruthenium Catalyst for Carbon Dioxide Hydrogenation

    Ying Min YU; Jin Hua FEI; Yi Ping ZHANG; Xiao Ming ZHENG


    Three kinds of cross linked polystyrene resin (PS) supported ruthenium complexes were developed as catalysts for the synthesis of formic acid from carbon dioxide hydrogenation. Many factors, such as the functionalized supports, solvents and ligands, could influence their activities and reuse performances greatly. These immobilized catalysts also offer the industrial advantages such as easy separation.

  15. Comparison of Cashew Nut Shell Liquid (CNS Resin with Polyester Resin in Composite Development

    C. C. Ugoamadi


    Full Text Available Natural resins can compete effectively with the synthetic ones in composite development. In this research, cashew nuts were picked and processed for the extraction of the resin content. The resin (natural resin so obtained was mixed with cobalt amine (accelerator, methyl ethyl ketone peroxide (catalyst to develop two sets of composite specimens – specimens without fibres and specimens reinforced with glass fibres. This method of sample specimen development was repeated with polyester (synthetic resin. Compressive and tensile strength tests conducted proved that composites developed with cashew nut shell liquid (CNSL resin were comparable to those developed with polyester resin. In the results, CNSL has an ultimate compressive strength of 55MPa compared to that of polyester resin with an ultimate strength of 68MPa. The result of tensile strength proved cashew nut shell liquid resin (with ultimate strength of 44MPa to be better than polyester resin with 39MPa as ultimate tensile strength. This means that natural resins could be a better substitute for the synthetic ones when the required quantities of fibers (reinforcements and fillers are used in the fibre-reinforced plastic composite developments.

  16. 负载型固体碱催化剂在酯交换反应中的研究进展%Progress in Research on Supported Solid Base Catalyst in Transesterification

    崔晓燕; 邓成


    At present transesterification is the main method to prepare biodiesel in industrial production. Supported solid base catalyst which is used to catalyze transesterification is a kind of environment friendly solid base catalyst. The studies on supported solid base catalysts applied in the transesterification at home and abroad are introduced which uses Al2O3, active carbon, ZrO2, microporous molecular sieves and mesoporous molecular sieves as carriers. It is proposed that the new supported solid base catalyst should meet the requirements of environmental protection and industrial demand.%酯交换法是目前生物柴油工业生产的主要方法,负载型固体碱催化剂是催化酯交换反应的一种环境友好型固体碱催化剂.介绍了国内外负载型固体碱催化剂(主要包括以Al2O3、活性炭、ZrO2、微孔分子筛和介孔分子筛为载体的固体碱催化剂)在酯交换反应中的研究情况,同时提出今后应进一步深入研究符合环保要求和工业化需求的新型负载型固体碱催化剂.


    Edy Cahyono


    Full Text Available Kinetic in cyclisation-acetylation of (R-(+-citronellal with acetic anhydride was investigated over Zn2+-Natural zeolite (Zn2+-Natzeo as a catalyst. (R-(+-citronellal has been isolated from citronella oil by fractional distillation under reducing pressure. Enantioselective capillary GC on a Supelco β-DEX 225 column has been used for analysis the enantiomers ratio of citronellal. Catalyst Zn2+-Natzeo has prepared through acid activation of natural zeolite from Malang using HF 1% and HCl 6 M, followed by ion-exchange with 3 M NH4Cl and calcination at 450 °C for 1 h under nitrogen to obtained H-natural zeolite (H-Natzeo. H-Natzeo was modified to Zn2+-Natzeo by ion exchange with 0.1 M ZnCl2. Cyclisation-acetylation reaction was carried out by heating (R-(+-citronellal (CIT, acetic anhydride (AA, and 1 g catalyst in glass batch reactor with vigorous stirring at 80 °C. Molar ratio CIT/AA that used, i.e. 0.25; 0.5; 1.0; 1.2 and 1.5. As the reaction proceeded, 1 mL sample was taken off at 10; 20; 30; 60; 120; 180 min and extracted using n-hexane for every molar ratio. Structure analysis of product was conducted by GC-MS. Kinetic of the cyclisation-acetylation reaction was analyzed according to the Langmuir-Hinshelwood mechanism. Increasing molar ratio of CIT/AA will decrease the isopulegyl acetate (IPA and neo-isopulegyl acetate (NIPA formation. Rate constant of cyclisation-acetylation reaction catalyzed by Zn2+-Natzeo was 30.964-47.619 mmol(min. g cat-1 at 80 °C, 30 min and the ratio  adsorption equilibrium constant KCIT/KAA was 7.09.   Keywords: Cyclisation-acetylation, (R-(+-citronellal, Zn2+-natural zeolite, kinetic

  18. 无机碳材料负载固相金属催化剂研究进展%Research progress in inorganic carbon material supported solid metal catalyst

    杨玉; 许佩瑶; 汪黎东


    综述了无机碳材料纳米碳管、活性炭纤维和膨胀石墨作为固相金属催化剂载体的国内外研究进展,探讨催化剂的不同负载方法,分析无机碳材料负载固相金属催化剂活性的影响因素及其应用领域。发现无机碳材料负载固相金属催化剂已经应用于催化加氢、光催化、电催化、水处理及大气处理方面,将其用于烟气脱硫副产物亚硫酸盐的处理,不仅能解决催化剂浪费问题,还能避免二次污染的发生。%The research progress in carbon nanotube materials,activated carbon fiber and expanded graphite as solid phase metallic catalyst carriers at home and abroad was reviewed. The different loading methods of the catalysts were discussed. The influence factors of the activity of the solid phase metallic catalysts sup-ported on inorganic carbon materials and their application fields were analyzed. It was found that the solid phase metallic catalysts supported on inorganic carbon materials were applied in the catalytic hydrogenation, photocatalysis,electro-catalysis,water treatment and air treatment. The solid phase metallic catalysts sup-ported on inorganic carbon materials were used for the treatment of by-product sulfite from flue gas desul-furization,which could solve the problem of the catalyst waste,and secondary pollution.

  19. Ionic liquids as efficient phase-transfer catalysts for the solid base-promoted monoalkylation of diethyl malonate

    Hui Sun; Juan Li; Xiao Chen Cai; Dong Jiang; Li Yi Dai


    Ionic liquids (ILs) based on 1,3-dialkylimidazolium and teraalkylammonium cations were employed as a series of efficient,environmentally benign phase-transfer catalysts (PTCs) for the base-promoted monoalkylation of diethyl malonate. The influence of various heterogeneous bases on yields was studied. Good yields and high selectivity were obtained. Solvent-free, mild reaction condition, short reaction time, and easy purification were the merits of this method. The catalytic system (IL-base) could also be recycled after the extraction of products with ether.

  20. Solid-Phase Random Glycosylation

    Agoston, K.; Kröger, Lars; Dekany, Gyula


    Two different approaches were employed to study solid phase random glycosylations to obtain oligosaccharide libraries. In approach I, Wang resin esters were attached to the acceptors structures. Following their glycosylation and resin cleavage, the peracetylated components of the oligosaccharide ...

  1. Session 4: Bio-diesel fuel (BDF) production by the trans-esterification of soybean and castor oils and the esterification of fatty acid using fixed bed reactor with solid super-acid and amorphous zirconia catalysts

    Satoshi, Furuta; Kyoji, Yano [Petroleum Refining Research and Technology Center, Japan Energy Corporation Niizo-minami, Toda, Saitama (Japan); Hiromi, Matsuhashi; Kazushi, Arata [Hokkaido University of Education, Dept. of Science, Hakodate (Japan)


    The monoesters produced by trans-esterification of vegetable oils with alcohol are known as bio-diesel fuel. Most of the bio-diesel fuels are currently made using alkaline catalysts, because the trans-esterification reaction by homogeneous acid catalysts are much slower than that by alkaline catalysts. There are several comprehensive studies of base catalyzed transesterification. The alkaline catalysts show high performance for obtaining vegetable oils with high quality, but a question often arises; that is, the oils contain significant amounts of free fatty acids, which cannot be converted into bio-diesels but to a lot of soap. As for solid catalysts, the uses of acid catalysts are quite few in contrast to solid bases. It appears that solid super-acids promote the trans-esterification of vegetable oils as well as the esterification of free fatty acids. Sulfated zirconia (SO{sub 4}/ZrO{sub 2}: SZA) and tungstate zirconia (WO{sub 3}/ZrO{sub 2}: WZA) are typical examples of those super acids and exhibit high catalytic activities for various reactions. Sulfated tin oxide (SO{sub 4}/SnO{sub 2}: STO) is one of the candidates with strong acidity on the surface. It has been reported that the acid strength is higher than that of SZ. This study was aimed to apply three types of solid super-acid catalysts and two types of amorphous zirconia catalysts to the transesterification of soybean oil and the esterification of normal octanoic acid with methanol. We also found that amorphous zirconia, doped with Al and Ti (Al/Zr, Ti/Zr), show high activities for the transesterification. The trans-esterification reaction was conducted in a fixed-bed once-through reactor with 4.0 g of catalyst. Methanol (4.4 g/h) and soybean oil (3.0 g/h), 40 in the molar ratio, were supplied to the reactor for 21 hrs. All catalysts showed little deactivation with time for WZA as an example. WZA together with amorphous zirconia, Al/Zr and Ti/Zr, showed quite high performance for the trans


    SUNWeimin; LUOJuntao; 等


    The solid-phase synthesis of isoxazolines on 2-polystyrylsulfonamidoethanol resin is reported.2-Polystyrylsulfonamidoethanol resin 1 was reacted with acryloyl chloride to afford 2-polystyrylsulfonylamidoethyl acrylate resin 2,which was further reacted with brominated aldoximes by [3+2] cycloaddition to give isoxazoline resin 4.Resin 4 was treated with aqueous 6 mol/L HCl solution to obtain isoxazolines in good yield and purity.

  3. Búsqueda de Catalizadores Sólidos Básicos para la Producción de Biodiesel Searching for Solid base Catalysts for Biodiesel Production

    Mónica Becerra


    Full Text Available Esta investigación tuvo como objetivo la búsqueda de catalizadores sólidos básicos activos y estables que contribuyan al desarrollo de sistemas de reacción heterogéneos para producción limpia de biodiesel. Se prepararon y evaluaron en la transesterificación de triacetina tres tipos de catalizadores: CaO, γ-Al2O3 modificada con Na y K, y MgO modificado con Na, Li, Rb y Cs. Se analizó la influencia de las propiedades texturales, tipo y cantidad de metal impregnado y la activación con N2, sobre la basicidad y el comportamiento catalítico. Se estudió la estabilidad de estos materiales mediante absorción atómica y reusos consecutivos. Los resultados mostraron que la impregnación de metales no conduce a la formación de sólidos estables, ya que éstos se lixivian en el medio de reacción. El CaO mantuvo una elevada actividad catalítica durante cinco ciclos de reacción convirtiéndolo en un material con alto potencial para ser utilizado en un proceso industrial.This work aimed to find active and stable solid base catalysts for clean biodiesel production using heterogeneous reaction systems. Three types of catalysts were synthesized and evaluated in the transesterification of triacetin: CaO, γ-Al2O3 modified with Na and K, and MgO modified with Na, Li, Rb and Cs. The influence of the textural proprieties, the type and amount of alkali metal impregnated and the activation with N2 on the basicity and the catalytic behavior were analyzed. Stability of catalysts was analyzed using atomic absorption measurements and reuse reactions. Results showed that metal impregnation does not lead to the formation of stable solids, because they present lixiviation in the reaction system. The CaO maintained a high catalytic activity during five reaction cycles showing its high potential of its use in an industrial process.

  4. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Styrene

    Hasmukh S. Patel


    Full Text Available Novel unsaturated poly (ester-amide resins (UPEAs were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Styrene (STY. to produce a homogeneous resin syrup. The curing of these UPEAs-STY. resin blends was carried out by using benzoyl peroxide (BPO as a catalyst and was monitored by using a differential scanning calorimeter (DSC. The glass fibre reinforced composites (i.e. laminates of these UPEA-STY. resin blends were fabricated using the DSC data. The chemical, mechanical and electrical properties of the glass fibre composites have also been evaluated. The unreinforced cured samples of the UPEA-STY. resin blends were also analyzed by thermogravimetry (TGA.

  5. Change of asphaltene and resin properties after catalytic aquathermolysis

    Yi Yufeng; Li Shuyuan; Ding Fuchen; Yu Hang


    Resin and asphaltene were separated from Liaohe heavy oil.Catalytic aquathermolysis of asphaltene and resin was investigated by using water soluble catalysts (NiSO4 and FeSO4) and oil soluble catalysts (nickel naphthenate and iron naphthenate).Before and after aquathermolysis, the properties of the resin and asphaltene was compared by means of ultimate analysis, vapor pressure osmometer (VPO) average molecular weight, X-ray diffraction (XRD), 13C and 1H nuclear magnetic resonance (NMR).The conversion sequence was as follows: No-catalystcatalysts, the amount of H2 and CO increased significantly, while H2S in the gas product decreased.The molecular weight of asphaltene and resin increased after reaction without catalyst.But the catalysts restrained this trend.The H/C ratio of asphaitene and resin decreased after reaction.From the results of average structural parameters and molecular weight, it was found that asphaltene and resin were partly aggregated after aquathermolysis.

  6. Oxidation catalyst

    Ceyer, Sylvia T.; Lahr, David L.


    The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

  7. 低成本E0级实木复合地板用PUF树脂胶的研制%Research on Low Cost PUF Resin for Manufacturing E0 Grade Solid Composition Flooring

    赵临五; 王春鹏; 张伟; 石建军; 储富祥


    按酚醛树脂的制备工艺,用NaOH为催化剂,在碱性条件下制备了U/P质量比为150%~158%的苯酚改性脲醛树脂.该胶制备工艺简单,反应平稳,操作易控制,再现性好,成本较低,贮存期达30d.该PUF胶压制的杨木三合板,桉-杨实木复合地板,胶合强度符合Ⅱ类胶合板的要求,甲醛释放量<0.5mg/L,100℃沸水煮6h浸渍剥离为0.%The phenol-urea-formaldehyde (PUF) resin for Eo degree flooring board were synthesized by alkali traditional process and using NaOH as the catalyst, with a U/P mass ratio of 150% - 158% and a F/ (P+U) mole ratio of 0.97 or 0.99. The adhesive production had many advantages of simple manufacture process, smooth reacting, easy operation and good reproducibility. The resulted PUF resins had such as low free formaldehyde, low free phenol, low cost and long reserving time(>30 days). The bond strength of PUF resin bonded composition flooring could meet the requirements of type Ⅱ plywood, the formaldehyde emission was less than 0.5mg/L, and no peeling off occurred in immersion test (PUF bonded samples immersed in l00℃ boiling water for 6hr).

  8. Transesterification of linoleic and oleic sunflower oils to biodiesel using CaO as a solid base catalyst

    Predojević Zlatica


    Full Text Available The purpose of this work is to characterize biodiesel (i.e. methyl esters, MEs produced from linoleic and oleic sunflower oils (LSO and OSO, respectively by alkali transesterification with methanol and CaO as a heterogeneous catalyst under different reaction parameters. The parameters investigated were the methanol/oil molar ratio (4.5:1, 6:1, 7.5:1, 9:1 and 12:1 and the mass ratio of CaO to oil (2% and 3%. The physical and chemical properties of the feedstocks and MEs, like density at 15oC, kinematic viscosity at 40oC, acid value, iodine value, saponification value, cetane index, fatty acid (methyl ester composition, were determined in order to investigate the effects of LSO and OSO properties and reaction parameters on the product characteristics, yields and purity. The properties of feedstock had decisive effect on the physical and chemical properties of MEs as majority of them did not differ significantly under studied reaction conditions. The MEs produced generally met the criteria required for commercial biodiesel; in fact, the only exception was in the case of iodine value of ME produced from LSO. The product yields only slightly changed with the applied conditions; the highest yield (99.22% was obtained for ME-LSO produced at 6 mol% methanol to oil ratio, while the lowest one (93.20% was for ME-OSO produced under the lowest methanol/oil molar ratio (4.5:1. The applied catalyst amounts had similar influence on the oil conversion to biodiesel. The yields of ME-LSOs were in general somewhat higher than those obtained for ME-OSOs under the same conditions, which was attributed to the influence of the respective feedstocks' acid value and viscosity.

  9. Resin composites

    Benetti, Ana Raquel; Peutzfeldt, Anne; Lussi, Adrian;


    OBJECTIVE: To investigate how the modulus of elasticity of resin composites influences marginal quality in restorations submitted to thermocyclic and mechanical loading. METHODS: Charisma, Filtek Supreme XTE and Grandio were selected as they were found to possess different moduli of elasticity...... of resin composite (p=0.81) on the quality of dentine margins was observed, before or after loading. Deterioration of all margins was evident after loading (p....008). CONCLUSIONS: The resin composite with the highest modulus of elasticity resulted in the highest number of gap-free enamel margins but with an increased incidence of paramarginal enamel fractures. CLINICAL SIGNIFICANCE: The results from this study suggest that the marginal quality of restorations can...

  10. Flow-injection spectrophotometric determination of captopril in pharmaceutical formulations using a new solid-phase reactor containing AgSCN immobilized in a polyurethane resin

    Fernando Campanhã Vicentini


    Full Text Available A simple flow-injection analysis procedure was developed for determining captopril in pharmaceutical formulations employing a novel solid-phase reactor containing silver thiocyanate immobilized in a castor oil derivative polyurethane resin. The method was based on silver mercaptide formation between the captopril and Ag(I in the solid-phase reactor. During such a reaction, the SCN- anion was released and reacted with Fe3+, which generated the FeSCN2+ complex that was continuously monitored at 480 nm. The analytical curve was linear in the captopril concentration range from 3.0 × 10-4 mol L-1 to 1.1 × 10-3 mol L-1 with a detection limit of 8.0 × 10-5 mol L-1. Recoveries between 97.5% and 103% and a relative standard deviation of 2% for a solution containing 6.0 × 10-4 mol L-1 captopril (n = 12 were obtained. The sample throughput was 40 h-1 and the results obtained for captopril in pharmaceutical formulations using this procedure and those obtained using a pharmacopoeia procedure were in agreement at a 95% confidence level.Um procedimento simples de análise por injeção em fluxo foi desenvolvido para a determinação de captopril em formulações farmacêuticas empregando um novo reator em fase sólida contendo tiocianato de prata imobilizado em resina poliuretana obtida a partir de óleo de mamona. O método foi baseado na formação de um mercapto composto de prata, no reator em fase sólida, obtido entre o captopril e Ag (I imobilizada. Durante a reação, íons SCN- eram liberados e reagiam com Fe3+, gerando o complexo FeSCN2+, que foi continuamente monitorado em 480 nm. A curva analítica foi linear no intervalo de concentração de captopril entre 3,0 × 10-4 a 1,1 × 10-3 mol L-1 com um limite de detecção de 8,0 × 10-5 mol L-1. Recuperações entre 97,5-103% e desvio padrão relativo de 2% para uma solução contendo 6,0 × 10-4 mol L-1 de captopril (n = 12 foram obtidos. A frequência de amostragem foi de 40 h-1 e os resultados

  11. Paraffin Alkylation Using Zeolite Catalysts in a slurry reactor: Chemical Engineering Principles to Extend Catalyst Lifetime

    Jong, K.P. de; Mesters, C.M.A.M.; Peferoen, D.G.R.; Brugge, P.T.M. van; Groot, C. de


    The alkylation of isobutane with 2-butene is carried out using a zeolitic catalyst in a well stirred slurry reactor. Whereas application of fixed bed technology using a solid acid alkylation catalyst has in the led to catalysts lifetimes in the range of minutes, in this work we report catalyst

  12. Soot combustion over Ce1-xFexO2-δ and CeO2/Fe2O3 catalysts: Roles of solid solution and interfacial interactions in the mixed oxides

    Li, Hongcheng; Li, Kongzhai; Wang, Hua; Zhu, Xing; Wei, Yonggang; Yan, Dongxia; Cheng, Xianming; Zhai, Kang


    Two series of CeO2-Fe2O3 catalysts (CeO2-based and Fe2O3-supported oxides) with varying composition were synthesized by a hydrothermal method and characterized using various techniques. The comparison on the activity and thermal stability of different catalysts for low-temperature soot oxidation was also performed. The presence of both Ce-Fe-O solid solution and CeO2-Fe2O3 interaction were observed over the two types of catalysts. The oxygen vacancy in the solid solution is the crucial active site to facilitating the soot combustion over the CeO2-based samples. Small CeO2 nanoparticles are well dispersed on the Fe2O3-supported catalysts, which results in the formation of Fe-O-Ce species due to the strong CeO2-Fe2O3 interaction. The Fe-O-Ce species could achieve the coupling of the Ce4+-Ce3+ and Fe3+-Fe2+ couples in the CeO2-Fe2O3 interface, which is also identified as an active species for catalytic soot oxidation. The concentration of oxygen vacancy is closely related to the content of iron in ceria lattice, while the formation of Fe-O-Ce species strongly relies on the particle size of CeO2. It is also found that the oxygen vacancy is more active than the Fe-O-Ce species for soot oxidation, but it is very easy to decompose at high temperature, resulting in obvious deactivation of catalysts. By contrast, the Fe-O-Ce species is very stable under high-temperature treatments. For the fresh samples, the CeO2-based and Fe2O3-supported catalysts showed comparable catalytic activity. After long term aging at 800 °C, the loss on activity over the CeO2-based catalyst (Ce-Fe-O solid solution) is much higher than that over the Fe2O3-supported sample. The Fe2O3-supported catalysts are more suitable for practical application than the Ce-Fe-O solid solution.

  13. Porous solid ion exchange wafer for immobilizing biomolecules

    Arora, Michelle B.; Hestekin, Jamie A.; Lin, YuPo J.; St. Martin, Edward J.; Snyder, Seth W.


    A porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer. Also disclosed is a porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer containing a biomolecule with a tag. A separate bioreactor is also disclosed incorporating the wafer described above.

  14. Protic acid immobilized on solid support as an extremely efficient recyclable catalyst system for a direct and atom economical esterification of carboxylic acids with alcohols.

    Chakraborti, Asit K; Singh, Bavneet; Chankeshwara, Sunay V; Patel, Alpesh R


    A convenient and clean procedure of esterification is reported by direct condensation of equimolar amounts of carboxylic acids with alcohols catalyzed by an easy to prepare catalyst system of perchloric acid immobilized on silica gel (HClO(4)-SiO(2)). The direct condensation of aryl, heteroaryl, styryl, aryl alkyl, alkyl, cycloalkyl, and long-chain aliphatic carboxylic acids with primary/secondary alkyl/cycloalkyl, allyl, propargyl, and long-chain aliphatic alcohols has been achieved to afford the corresponding esters in excellent yields. Chiral alcohol and N-t-Boc protected chiral amino acid also resulted in ester formation with the representative carboxylic acid or alcohol without competitive N-t-Boc deprotection and detrimental effect on the optical purity of the product demonstrating the mildness and chemoselectivity of the procedure. The esters of long-chain (>C(10)) acids and alcohols are obtained in high yields. The catalyst is recovered and recycled without significant loss of activity. The industrial application of the esterification process is demonstrated by the synthesis of prodrugs of ibuprofen and a few commercial flavoring agents. Other protic acids such as H(2)SO(4), HBr, TfOH, HBF(4), and TFA that were adsorbed on silica gel were less effective compared to HClO(4)-SiO(2) following the order HClO(4)-SiO(2) > H(2)SO(4)-SiO(2) > HBr-SiO(2) > TfOH-SiO(2) > HBF(4)-SiO(2) approximately TFA-SiO(2). When HClO(4) was immobilized on other solid supports the catalytic efficiency followed the order HClO(4)-SiO(2) > HClO(4)-K10 > HClO(4)-Al(2)O(3) (neutral) > HClO(4)-Al(2)O(3) (acidic) > HClO(4)-Al(2)O(3) (basic).

  15. Structure-property relationships of solid polymeric catalysts: isopropanol dehydration to propylene catalyzed by sulfonated polyethylene-grafted styrene

    Cooper, C.A.


    Isopropanol dehydration to propylene catalyzed by sulfonated polyethylene-grafted styrene was used to measure the effects on the catalytic activity of structural charges induced in the membranes by constant-rate, cold drawing by 75, 150, and 200 3< of their initial lengths. The form of the rate expression for the reaction with undrawn and drawn membranes at 100/sup 0/C and 1 atm under differential reaction conditions was the same and could be explained by a concerted reaction mechanism involving intermediate isopropanol hydrogen bonded to about four -SO/sub 3/H groups. The maximum reaction rate (based on catalyst acidity) increased by approx. 80% from the undrawn membrane to the 150% drawn membrane and then decreased by approx. 70% from the maximum observed for the 150% drawn membrane to the 200% drawn membrane. A structural model was developed on the basis that the -SO/sub 3/H groups are confined to the amorphous phase due to steric exclusion but that they redistribute to more favorable arrangements during drawing. Model predictions were supported by X-ray and birefringence studies.

  16. Ethylated Urea - Ether - Modified Urea - Formaldehyde Resins,

    Mathew Obichukwu EDOGA


    Full Text Available First, phenol - formaldehyde (PF and urea - formaldehyde (UFII resins were separately conventionally prepared in our laboratory. Also, UF resin synthesized from the acid modified synthesis procedure was synthesized in a purely acid medium of pH 1.0, FU molar ratio of 1.0 and at 50oC (one-stage acid modified-synthesis procedure. Subsequently, the UF resin II was modified during synthesis by incorporating ethylated urea-ether (EUER (i.e. UFIII and glycerol (GLYC (i.e. UFV cured with and without acid curing agent. The structural and physicochemical analyses of the various resin samples were carried out.The results showed that the unmodified UF resin (UF II synthesized in acid medium of pH 1.0, F/U molar ratio 1.0, and at 50oC, cured in absence of acid curing catalyst, showed features in their spectra which are consistent with a tri-, and/or tetra-substituted urea in the reaction to give a 3 - dimensional network cured UF resin. Modification of the UF resin(UF II with ethylated urea-ether and glycerol to produce UF resins III and respectively V prominently increased the absorbance of methylene and ether groups in the spectra which are consistent with increased hydrophobicity and improved hydrolytic stability. For the conventional UF resin (UF I, the only clear distinction between spectra for the UF resin II and UF resins (III/V is the presence of diminished peaks for methylene groups at 2.2 ppm. The relationship between the logarithmic viscosity of cured PF resin with time showed continuos dependence of viscosity with time during cure up to 70 minutes. Similar trends were shown by UF resins (III/V, cured in absence of acid catalyst. In contrast, the conventional UF resins I and UF IV (i.e. UF II cured with NH4CL showed abrupt discontinuity in viscosity with time just after about 20 minutes of cure.

  17. A nickel tripeptide as a metallodithiolate ligand anchor for resin-bound organometallics.

    Green, Kayla N; Jeffery, Stephen P; Reibenspies, Joseph H; Darensbourg, Marcetta Y


    The molecular structure of the acetyl CoA synthase enzyme has clarified the role of individual nickel atoms in the dinickel active site which mediates C-C and C-S coupling reactions. The NiN2S2 portion of the biocatalyst (N2S2 = a cysteine-glycine-cysteine or CGC4- tripeptide ligand) serves as an S-donor ligand comparable to classical bidentate ligands operative in organometallic chemistry, ligating the second nickel which is redox and catalytically active. Inspired by this biological catalyst, the synthesis of NiN2S2 metalloligands, including the solid-phase synthesis of resin-bound Ni(CGC)2-, and sulfur-based derivatization with W(CO)5 and Rh(CO)2+ have been carried out. Through comparison to analogous well-characterized, solution-phase complexes, Attenuated Total Reflectance FTIR spectroscopy establishes the presence of unique heterobimetallic complexes, of the form [Ni(CGC)]M(CO)x, both in solution and immobilized on resin beads. This work provides the initial step toward exploitation of such an evolutionarily optimized nickel peptide as a solid support anchor for hybrid bioinorganic-organometallic catalysts.

  18. Bimetallic-catalyst-mediated syntheses of nanomaterials (nanowires, nanotubes, nanofibers, nanodots, etc) by the VQS (vapor-quasiliquid-solid, vapor- quasisolid-solid) growth mechanism

    Mohammad, S. N.


    The enhanced synergistic, catalytic effect of bimetallic nanoparticles (BNPs), as compared to monometallic nanoparticles (NPs), on the nanomaterials (nanowires, nanotubes, nanodots, nanofibers, etc) synthesed by chemical vapor deposition has been investigated. A theoretical model for this catalytic effect and hence for nanomaterial growth, has been developed. The key element of the model is the diffusion of the nanomaterial source species through the nanopores of quasiliquid (quasisolid) BNP, rather than through the liquid or solid BNP, for nanomaterial growth. The role of growth parameters such as temperature, pressure and of the BNP material characteristics such as element mole fraction of BNP, has been studied. The cause of enhanced catalytic activity of BNPs as compared to NPs as a function of temperature has been explored. The dependence of growth rate on the nanomaterial diameter has also been examined. The calculated results have been extensively compared with available experiments. Experimental supports for the growth mechanism have been presented as well. Close correspondence between the calculated and experimental results attests to the validity of the proposed model. The wide applicability of the proposed model to nanowires, nanotubes, nanofibers, nanodots, etc suggests that it is general and has broad appeal.

  19. Redox properties of manganese-containing zirconia solid solution catalysts analyzed by in situ UV-vis spectroscopy and crystal field theory.

    Klokishner, Sophia I; Reu, Oleg; Chan-Thaw, Carine E; Jentoft, Friederike C; Schlögl, Robert


    The optical absorption spectra of manganese-promoted sulfated zirconia, a highly active alkane isomerization catalyst, were found to be characterized by oxygen-to-manganese charge-transfer transitions at 300-320 nm and d-d transitions of manganese ions at 580 and 680 nm. The latter were attributed to Mn(4+) and Mn(3+) ions, which are known to be incorporated in the zirconia lattice. The oxygen surroundings of these ions were modeled assuming a substitutional solid solution. The crystal field splittings, vibronic coupling constants, and oscillator strengths of the manganese ions were calculated on the basis of a cluster model that considers the manganese center as a complex with the adjacent ions of the lattice as ligands. The ratio of Mn(3+) to Mn(4+) ions was determined using the spectra and the model, and the relative concentrations of Mn(2+), Mn(3+), and Mn(4+) ions were determined with the help of the average valence known from X-ray absorption data in the literature. The redox behavior of manganese-promoted sulfated zirconia in oxidizing and inert atmosphere was elucidated at temperatures ranging from 323 to 773 K.

  20. Effect of praseodymium on catalytic graphitization of furan resin carbon

    易守军; 陈金华; 肖雄; 刘露; 樊桢


    We introduced a new catalyst,rare earth element praseodymium,for the catalytic graphitization of furan resin carbon.The extent of graphitization of the furan resin carbon was examined by X-ray diffraction and Raman spectroscopy.The morphology of furan resin carbon was characterized by scanning electron microscopy.The effects of the praseodymium content and the heat-treatment temperature on the catalytic graphitization of furan resin carbon were also investigated.The results indicated that the praseodymium c...

  1. Catalytic synthesis of C4-6 mixed dimethyl esters with composite solid acid catalyst%固体酸催化合成C4~6混合二元酸二甲酯

    崔欣; 黄集钺; 石鸣彦


    C4-6 mixed dimethyl esters (DME) are prepared using C4-6 mixed dibasic acids (DBA) and methanol as raw materials and composite solid acid as catalyst.The effects are tested in different reaction condition of catalyst, reaction time, mole ratio of methanol to DBA, catalyst amount and catalyst recycled times.The optimum conditions are as follows: reaction temperature 74~82 ℃, mole ratio of methanol to DBA 5/1, dosage of composite solid acid mass ratio to DBA 10 % and reaction time 4.5 h.Under these conditions, the yield of DME is 87.8 %.When composite solid acid is recycled for 4 times, the yield of DME is still above 80%, which shows good stability and reusability of composite solid acid.%以C4~6混合二元酸、甲醇为原料,回体酸为催化剂,合成C4~6混合二元酸二甲酯.进行了不同种类催化剂筛选、反应工艺条件优化及催化剂寿命的实验研究,确定了适宜的酯化反应条件:以于氢树脂酸为催化剂,反应时间4.5 h、酸醇物质的量比1:5、催化剂加入量10%、反应温度74~82℃.在此条件下,混合二元酸转化率达87.8%.干氢树脂酸催化剂连续使用4次时,混合二元酸转化率仍达80%以上.

  2. Highly cost-effective and sulfur/coking resistant VOx-grafted TiO2 nanoparticles as an efficient anode catalyst for direct conversion of dry sour methane in solid oxide fuel cells

    Garcia, A.; Yan, N.; Vincent, A.; Singh, A.; Hill, J.M.; Chuang, K. T.; Luo, J.L.


    In this work, we show that grafted metal oxide can be a highly cost-effective and active anode for solid oxide fuel cells for sour methane conversion. The developed electro-catalyst was composed of vanadium oxide grafted TiO2 nanoparticles (VOx/TiO2) infiltrated into a porous La0.4Sr0.5Ba0.1TiO3+δ e

  3. Metal oxide nanostructures synthesized on flexible and solid substrates and used for catalysts, UV detectors, and chemical sensors

    Willander, Magnus; Sadollahkhani, Azar; Echresh, Ahmad; Nur, Omer


    In this paper we demonstrate the visibility of the low temperature chemical synthesis for developing device quality material grown on flexible and solid substrates. Both colorimetric sensors and UV photodetectors will be presented. The colorimetric sensors developed on paper were demonstrated for heavy metal detection, in particular for detecting copper ions in aqueous solutions. The demonstrated colorimetric copper ion sensors developed here are based on ZnO@ZnS core-shell nanoparticles (CSNPs). These sensors demonstrated an excellent low detection limit of less than 1 ppm of copper ions. Further the colorimetric sensors operate efficiently in a wide pH range between 4 and 11, and even in turbulent water. The CSNPs were additionally used as efficient photocatalytic degradation element and were found to be more efficient than pure ZnO nanoparticles (NPs). Also p-NiO/n-ZnO thin film/nanorods pn junctions were synthesized by a two-step synthesis process and were found to act as efficient UV photodetectors. Additionally we show the effect of the morphology of different CuO nanostructures on the efficiency of photo catalytic degradation of Congo red organic dye.

  4. Synthesis and Evaluation of Cu/SAPO-34 Catalysts for NH3-SCR 2: Solid-state Ion Exchange and One-pot Synthesis

    Gao, Feng; Walter, Eric D.; Washton, Nancy M.; Szanyi, Janos; Peden, Charles HF


    Cu-SAPO-34 catalysts are synthesized using two methods: solid-state ion exchange (SSIE) and one-pot synthesis. SSIE is conducted by calcining SAPO-34/CuO mixtures at elevated temperatures. For the one-pot synthesis method, Cu-containing chemicals (CuO and CuSO4) are added during gel preparation. A high-temperature calcination step is also needed for this method. Catalysts are characterized with surface area/pore volume measurements, temperature programmed reduction (TPR), electron paramagnetic resonance (EPR) and nuclear magnetic resonance (NMR) spectroscopies, and scanning electron microscopy (SEM). Catalytic properties are examined using standard ammonia selective catalytic reduction (NH3-SCR) and ammonia oxidation reactions. In Cu-SAPO-34 samples formed using SSIE, Cu presents both as isolated Cu2+ ions and unreacted CuO. The former is highly active and selective in NH3-SCR, while the latter catalyzes a side reaction; notably, the non-selective oxidation of NH3 above 350 ºC. Using the one-pot method followed by a high-temperature aging treatment, it is possible to form Cu SAPO-34 samples with predominately isolated Cu2+ ions at low Cu loadings. However at much higher Cu loadings, isolated Cu2+ ions that bind weakly with the CHA framework and CuO clusters also form. These Cu moieties are very active in catalyzing non-selective NH3 oxidation above 350 ºC. Low-temperature reaction kinetics indicate that Cu-SAPO-34 samples formed using SSIE have core-shell structures where Cu is enriched in the shell layers; while Cu is more evenly distributed within the one-pot samples. Reaction kinetics also suggest that at low temperatures, the local environment next to Cu2+ ion centers plays little role on the overall catalytic properties. The authors gratefully acknowledge the US Department of Energy (DOE), Energy Efficiency and Renewable Energy, Vehicle Technologies Office for the support of this work. The research described in this paper was performed at the Environmental

  5. Combined use of titration calorimetry and spectrofluorimetry for the screening of the acidity of solid catalysts in different liquids

    Gervasini, Antonella, E-mail: [Dipartimento di Chimica, Università degli Studi di Milano, via Camillo Golgi, 19, 20133 Milano (Italy); Auroux, Aline, E-mail: [Université Lyon 1, CNRS, UMR 5256, Institut de Recherches sur la Catalyse et l‘Environnement de Lyon (IRCELYON), 2 Avenue A. Einstein, 69626 Villeurbanne (France)


    Graphical abstract: Measurements of acidity of oxides of catalytic importance in various liquids open the possibility to know their effective acidity, which is related with their activity in liquid-heterogeneous catalysis. Titration-calorimetry alone or in connection with spectrofluorimetry is efficient for this scope. - Highlights: • Measurements of acidity of oxides of catalytic importance in various liquids. • Titration-calorimetry alone or in connection with spectrofluorimetry is efficient for this scope. • Effective acidities are expressed by given sample in various liquids. • Nb-containing samples are able to maintain acidity in protic liquids. - Abstract: The effective acid and base surface properties of selected acidic and basic samples of catalytic interest (alumina, titania, zirconia, silica–alumina, niobium oxide, niobium phosphate, boron nitride, and hydrotalcite) were measured by titration with basic and acidic molecular probes (aniline, 2-phenylethylamine, and phenol) in various liquids (cyclohexane, 1,4-dioxane, isopropanol, n-decane, and toluene) with different polar and protic characteristics. The combined use of a reaction calorimeter and a spectrofluorimeter has been performed. The set-up of the coupled technique and the most interesting results are shown here. The study confirmed that the acid–base properties of solids are deeply affected by the nature and properties of the liquid surrounding the samples. Few oxides are able to maintain their surface acidity in highly polar and protic solvents, in particular whose containing niobium. In general, the solvating and coordinative ability of the most polar and protic liquids caused remarkable loss of acidity/basicity of the oxide surfaces.

  6. Review: Resin Composite Filling

    Desmond Ng; Jimmy C. M. Hsiao; Keith C. T. Tong; Harry Kim; Yanjie Mai; Keith H. S. Chan


    The leading cause of oral pain and tooth loss is from caries and their treatment include restoration using amalgam, resin, porcelain and gold, endodontic therapy and extraction. Resin composite restorations have grown popular over the last half a century because it can take shades more similar to enamel. Here, we discuss the history and use of resin, comparison between amalgam and resin, clinical procedures involved and finishing and polishing techniques for resin restoration. Although resin ...

  7. Synthesis and Characterizations of Melamine-Based Epoxy Resins

    Raffaele Cioffi


    Full Text Available A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I or by adding a silane derivative (resin II. The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials.

  8. Synthesis and characterizations of melamine-based epoxy resins.

    Ricciotti, Laura; Roviello, Giuseppina; Tarallo, Oreste; Borbone, Fabio; Ferone, Claudio; Colangelo, Francesco; Catauro, Michelina; Cioffi, Raffaele


    A new, easy and cost-effective synthetic procedure for the preparation of thermosetting melamine-based epoxy resins is reported. By this innovative synthetic method, different kinds of resins can be obtained just by mixing the reagents in the presence of a catalyst without solvent and with mild curing conditions. Two types of resins were synthesized using melamine and a glycidyl derivative (resins I) or by adding a silane derivative (resin II). The resins were characterized by means of chemical-physical and thermal techniques. Experimental results show that all the prepared resins have a good thermal stability, but differ for their mechanical properties: resin I exhibits remarkable stiffness with a storage modulus value up to 830 MPa at room temperature, while lower storage moduli were found for resin II, indicating that the presence of silane groups could enhance the flexibility of these materials. The resins show a pot life higher than 30 min, which makes these resins good candidates for practical applications. The functionalization with silane terminations can be exploited in the formulation of hybrid organic-inorganic composite materials.

  9. Development of a solid phantom prototype of Mo-99, Tc-99, and Co-57 in epoxy resins for evaluating of the uniformity in SPECT systems images; Desarrollo de un prototipo de fantoma solido de Mo-99, Tc-99, y Co-57 en resinas epoxicas para evaluacion de la uniformidad en imagenes de sistemas SPECT

    Garcia D, O.C. [Facultad de Medicina, UAEM, Toluca, Mexico (Mexico); Cortes P, A.; Becerril V, A. [Instituto Nacional de Investigaciones Nucleares, A.P. 18-1027, 11801 Mexico D.F. (Mexico); Garcia R, J.C. [Instituto de Psiquiatria Ramon de la Fuente, Mexico D.F. (Mexico)


    A manufacture method of solid phantoms prototype of resin with different radioisotopes is described. The phantom manufactured of molybdenum 99 has an uniformity of 96% determined with a Na(Tl) detector mono channel analyzer with a lead collimator of 1 cm diameter. (Author)

  10. A flexible and versatile strategy for the covalent immobilization of chiral catalysts based on pyridinebis(oxazoline) ligands.

    Cornejo, Alfonso; Fraile, José M; García, José I; Gil, María J; Luis, Santiago V; Martínez-Merino, Víctor; Mayoral, José A


    [reaction: see text] Flexible and versatile methods have been developed for the immobilization of chiral pyridinebis(oxazoline) ligands by covalent bonding to a solid support, either by grafting or by polymerization. Different spacers can easily be introduced to modulate the support-ligand distance and the electronic properties of the chiral ligand. As an example, 2,6-bis[(S)-4-isopropyloxazolin-2-yl]pyridine has been immobilized on polystyrene resins, both on a Merrifield-type resin by grafting and on supports prepared by polymerization of 4-vinyl-substituted ligands. The corresponding Ru complexes have been tested as catalysts in the cyclopropanation reaction between styrene and ethyl diazoacetate. The catalytic activity, the enantioselectivity, and the recyclability are strongly dependent on the catalyst preparation method and the total exclusion of oxygen and moisture in the filtration process. Under such optimized conditions, yields over 60% with up to 90% ee can be obtained in four successive reactions-the best cyclopropanation results described to date for a chiral solid ruthenium catalyst.

  11. 高固体份新型树脂改性硝基清漆的研制%Study on modification of nitrocellulose varnish by high solid new type resin

    孙立德; 李施扬; 韩文超


    本文主要研究了利用硝化纤维素本身存在-OH和-NO2基,通过交联反应,用新型树脂进行改性,使改性的硝基清漆的固体份由原来的30%提高到40%,克服了原硝基清漆的弱点.%The new type resin was modified by cross linking reaction using -OH and NO2 group in nitro-cotton. The solid fraction of modified nitrocellulose varnish was raised from 30% to 40%. The defaults of original nitrocellulose varnish were overcome.

  12. Operando UV-Vis spectroscopy of a catalytic solid in a pilos-scale reactor: deactivation of a CrOx/Al2O3 propane dehydrogenation catalyst

    Sattler, J.J.H.B.|info:eu-repo/dai/nl/328235601; Gonzalez-Jimenez, I.D.; Mens, A.J.M.|info:eu-repo/dai/nl/313707065; Arias, M.J.|info:eu-repo/dai/nl/314076727; Visser, T.|info:eu-repo/dai/nl/110288327; Weckhuysen, B.M.|info:eu-repo/dai/nl/285484397


    A novel operando UV-Vis spectroscopic set-up has been constructed and tested for the investigation of catalyst bodies loaded in a pilot-scale reactor under relevant reaction conditions. Spatiotemporal insight into the formation and burning of coke deposits on an industrial CrOx/Al2O3 catalyst during

  13. Operando UV-Vis spectroscopy of a catalytic solid in a pilos-scale reactor: deactivation of a CrOx/Al2O3 propane dehydrogenation catalyst

    Sattler, J.J.H.B.; Gonzalez-Jimenez, I.D.; Mens, A.J.M.; Arias, M.J.; Visser, T.; Weckhuysen, B.M.


    A novel operando UV-Vis spectroscopic set-up has been constructed and tested for the investigation of catalyst bodies loaded in a pilot-scale reactor under relevant reaction conditions. Spatiotemporal insight into the formation and burning of coke deposits on an industrial CrOx/Al2O3 catalyst during

  14. A conditioning process for ion exchanger resins contaminated with radioactive elements. Procede de conditionnement de resines echangeuses d'ions contaminees par des elements radioactifs

    Legros, R.; Wiegert, B.; Zeh, J.L.


    Ion exchanger resins are embedded in a pre-polymer syrup prepared from acrylic monomers having high boiling point. A curing catalyst (a peroxide) and an activation agent (a tertiary amine) are added. 12 examples are given. 9 p.

  15. Determination of palladium, platinum and rhodium in used automobile catalysts and active pharmaceutical ingredients using high-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sample analysis

    Resano, Martín, E-mail: [Department of Analytical Chemistry, Aragón Institute of Engineering Research (I3A), University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Flórez, María del Rosario [Department of Analytical Chemistry, Aragón Institute of Engineering Research (I3A), University of Zaragoza, Pedro Cerbuna 12, 50009 Zaragoza (Spain); Queralt, Ignasi [Institute of Earth Sciences Jaume Almera ICTJA-CSIC, Sole Sabarís s/n, 08028 Barcelona (Spain); Marguí, Eva [Department of Chemistry, Faculty of Sciences, Universitat de Girona, Campus Montilivi s/n, 17071 Girona (Spain)


    This work investigates the potential of high-resolution continuum source graphite furnace atomic absorption spectrometry for the direct determination of Pd, Pt and Rh in two samples of very different nature. While analysis of active pharmaceutical ingredients is straightforward and it is feasible to minimize matrix effects, to the point that calibration can be carried out against aqueous standard solutions, the analysis of used automobile catalysts is more challenging requiring the addition of a chemical modifier (NH{sub 4}F·HF) to help in releasing the analytes, a more vigorous temperature program and the use of a solid standard (CRM ERM®-EB504) for calibration. However, in both cases it was possible to obtain accurate results and precision values typically better than 10% RSD in a fast and simple way, while only two determinations are needed for the three analytes, since Pt and Rh can be simultaneously monitored in both types of samples. Overall, the methods proposed seem suited for the determination of these analytes in such types of samples, offering a greener and faster alternative that circumvents the traditional problems associated with sample digestion, requiring a small amount of sample only (0.05 mg per replicate for catalysts, and a few milligrams for the pharmaceuticals) and providing sufficient sensitivity to easily comply with regulations. The LODs achieved were 6.5 μg g{sup −1} (Pd), 8.3 μg g{sup −1} (Pt) and 9.3 μg g{sup −1} (Rh) for catalysts, which decreased to 0.08 μg g{sup −1} (Pd), 0.15 μg g{sup −1} (Pt) and 0.10 μg g{sup −1} (Rh) for pharmaceuticals. - Highlights: • Solid sampling HR CS GFAAS permits the fast and direct determination of Pd, Pt and Rh. • 2 determinations suffice for the 3 elements (2 of them can be measured simultaneously). • Samples as different as car catalysts and pharmaceuticals can be accurately analyzed. • Aqueous standards (pharmaceuticals) or a solid CRM (catalysts) is used for calibration.

  16. Single Pellet String Reactor for Intensification of Catalyst Testing in Gas/Liquid/Solid Configuration Réacteur catalytique de type “filaire” pour l’intensification de tests catalytiques en configuration gaz/liquide/solide

    Hipolito A.I.


    has been shown that the pressure drop is controlled by the liquid/solid friction surface and that the pressure drop is not a limiting parameter in the reactor’s operation (values always lower than 0.1 bar. So, from a hydrodynamic point of view, this new reactor exhibits characteristics suitable for its use in catalytic tests. Finally, this reactor was implemented under reaction conditions to study hydrogenation reactions with a real industrial catalyst. The selective hydrogenation of allene was studied. The string reactor was shown to run isothermal kinetic tests with a very small amount of industrial-sized catalyst particles (less than 2 cc and to explore kinetics of fast reaction at high space velocities impossible to achieve in standard fixed bed units with appropriate hydrodynamic conditions. For constant residence time, the allene conversion does not vary with pressure and feed flow rate, which confirms that the string reactor allows one to perform catalytic tests with such a fast reaction without external mass transfer resistance. L’optimisation du catalyseur est une etape cle pour l’optimisation d’un procede catalytique du point de vue des rendements, de l’efficacite energetique et de la selectivite des reactions. La strategie de developpement d’un catalyseur comprend des tests effectues sur des reacteurs pilotes avec des charges reelles ou modeles. Cette etape a fait l’objet de nombreuses etudes ces dernieres decennies portant sur le dimensionnement des reacteurs, l’amelioration des outils d’analyses et les procedures operatoires. La plupart des etudes ont pour but de determiner l’activite catalytique de catalyseur sous forme de grain dans des conditions isothermes de facon a pouvoir determiner les parametres cinetiques de la reaction. Avec l’optimisation des catalyseurs, les flux de transfert de matieres externes aux grains peuvent devenir l’etape limitante, dans les reacteurs de laboratoire standard, par rapport aux flux de reaction

  17. Large Scale Solid Phase Synthesis of Peptide Drugs: Use of Commercial Anion Exchange Resin as Quenching Agent for Removal of Iodine during Disulphide Bond Formation

    K. M. Bhaskara Reddy


    Full Text Available The S-acetamidomethyl (Acm or trityl (Trt protecting groups are widely used in the chemical synthesis of peptides that contain one or more disulfide bonds. Treatment of peptides containing S-Acm protecting group with iodine results in simultaneous removal of the sulfhydryl protecting group and disulfide formation. However, the excess iodine needs to be quenched or adsorbed as quickly as possible after completion of the disulfide bond formation in order to minimize side reactions that are often associated with the iodination step. We report here a simple method for simultaneous quenching and removal of iodine and isolation of disulphide bridge peptides. The use of excess inexpensive anion exchange resin to the oxidized peptide from the aqueous acetic acid/methanol solution affords quantitative removal of iodine and other color impurities. This improves the resin life time of expensive chromatography media that is used in preparative HPLC column during the purification of peptide using preparative HPLC. Further, it is very useful for the conversion of TFA salt to acetate in situ. It was successfully applied commercially, to the large scale synthesis of various peptides including Desmopressin, Oxytocin, and Octreotide. This new approach offers significant advantages such as more simple utility, minimal side reactions, large scale synthesis of peptide drugs, and greater cost effectiveness.

  18. Determination of Some Trace Metals in Environmental Samples by Flame AAS Following Solid Phase Extraction with Amberlite XAD-2000 Resin after Complexing with 8-Hydroxyquinoline

    DURAN Celal; SENTURK H.Basri; GUNDOGDU Ali; BULUT V.Numan; EICi Latif; SOYLAK Mustafa; TUFEKCI,Mehmet; UYGUR Yaprak


    A procedure for preconcentration of Mn(Ⅱ), Fe(Ⅱ), Co(Ⅱ), Cu(Ⅱ), Cd(Ⅱ), Zn(Ⅱ), Pb(Ⅱ) and Ni(Ⅱ) based on retention of their complexes with 8-hydroxyquinoline (HQ) on Amberlite XAD-2000 resin in a column was proposed for the analysis of environmental samples by flame AAS. Various parameters such as pH, eluent type, volume,concentration, flow rate and volume of sample solution, and matrix interference effect on the retention of the metal ions were investigated. The optimum pHs for the retention of metal complexes in question were about 6 except for Mn2+ for whose value is 8. The loading capacity of the adsorbent for these metals and their recoveries from the resin under the optimum conditions were in the range 6.82-9.26 mg·g-1 and 95%-101%, respectively. The enrichment factor was calculated as 100 and the limit of detection was in the range 0.3-2.2 μg·L 1 (n=20, blank+3s). The proposed enrichment method was applied to tap water, stream water and vegetable samples. The validation of the procedure was carried out by analysis of certified reference material and standard addition. The analytes were determined with a relative standard deviation lower than 6% in all samples.

  19. Mechanochemistry, catalysis, and catalysts

    Butyagin, P.Yu.


    The physical basis of mechanochemistry and the reasons for the initiation and acceleration of chemical reactions upon the mechanical treatment of solids have been considered. The phenomenon of mechanical catalysis has been described in the example case of the oxidation of CO on oxide surfaces, and the nature of the active sites and the laws governing the mechanically activated chemisorption of gases on cleavage and friction surfaces of solids have been examined. The possibilities of the use of the methods of mechanochemistry in processes used to prepare catalysts have been analyzed in examples of decomposition reactions of inorganic compounds and solid-phase synthesis.

  20. TMI-2 purification demineralizer resin study

    Thompson, J D; Osterhoudt, T R


    Study of the Makeup and Purification System demineralizers at TMI-2 has established that fuel quantities in the vessels are low, precluding criticality, that the high radioactive cesium concentration on the demineralizer resins can be chemically removed, and that the demineralizer resins can probably be removed from the vessels by sluicing through existing plant piping. Radiation measurements from outside the demineralizers establishing that there is between 1.5 and 5.1 (probably 3.3) lb of fuel in the A vessel and less than that amount in the B vessel. Dose rates up to 2780 R per hour were measured on contact with the A demineralizer. Remote visual observation of the A demineralizer showed a crystalline crust overlaying amber-colored resins. The cesium activity in solid resin samples ranged from 220 to 16,900 Based on this information, researchers concluded that the resins cannot be removed through the normal pathway in their present condition. Studies do show that the resins will withstand chemical processing designed to rinse and elute cesium from the resins. The process developed should work on the TMI-2 resins.

  1. Poly(4-vinylpyridinium) perchlorate as an efficient solid acid catalyst for the chemoselective preparation of 1,1-diacetates from aldehydes under solvent-free conditions

    Nader Ghaffari Khaligh


    Poly(4-vinylpyridinium) perchlorate has been used as a supported, recyclable, environmental-ly-benign catalyst for the formation of acylals from aliphatic and aromatic aldehydes in good to excellent yields under solvent-free conditions. Notably, the reaction conditions were tolerant of ketones. This methodology offers several distinct advantages, including its operational simplicity and high product yield, as well as being green in terms of avoiding the use of toxic catalysts and solvents. Furthermore, the catalyst can be recovered and reused several times without any loss in its activity.

  2. Mesoporous molecular sieve catalysts

    Højholt, Karen Thrane

    be used as solid acid catalysts but can also be used as a size-selective matrix. It was shown that it is possible to encapsulate 1-2 nm sized gold nanoparticles by silicalite-1 or ZSM-5 zeolite crystals thereby forming a sintering-stable and substrate size-selective oxidation catalyst. After carrying out...... calcination experiments, both in situ and ex situ indicated that the gold nanoparticles embedded in the crystals were highly stable towards sintering. The catalytic tests proved that the embedded gold nanoparticles were active in selective aldehyde oxidation and were only accessible through the micropores...

  3. Solid superacid catalyst SO42-/Kaolin for preparation of levulinic acid%固体超强酸催化剂SO42-/高岭土制备乙酰丙酸

    刘焘; 李利军; 黄文艺; 刘柳


    Solid superacid catalyst SO42−/Kaolin was prepared by twice impregnation-roasting,and the synthesis mechanism of conversion of lactose to levulinic acid was studied. The effects of technological condition , such as catalyst calcination temperature , catalyst dosage , lactose concentration,reaction temperature,reaction time on the relative yield of levulinic acid were investigated and orthogonal experiment was used to determine the optimum conditions. The result showed that the highest relative yield of levulinic acid was 79.13% under the optimal conditions of catalyst calcination temperature 650 ℃,lactose concentration 5 g/L,reaction temperature 200 ℃, reaction time 120 min,catalyst dosage 15%of lactose.%  利用二次浸渍焙烧法制备固体超强酸催化剂SO42−/高岭土,对其催化水解乳糖制备乙酰丙酸的反应机理作了推理,并通过单变量法考察了催化剂的焙烧温度、乳糖浓度、反应温度、反应时间、催化剂用量等对乙酰丙酸相对收率的影响,采用正交实验来确定最佳工艺条件,研究结果表明:当催化剂的焙烧温度为650℃、乳糖浓度5 g/L、反应温度200℃、反应时间120 min、催化剂用量为乳糖加入量的15%时,乙酰丙酸的相对收率最大,达到79.13%。

  4. A comparative study of solid carbon acid catalysts for the esterification of free fatty acids for biodiesel production. Evidence for the leaching of colloidal carbon.

    Deshmane, Chinmay A; Wright, Marcus W; Lachgar, Abdessadek; Rohlfing, Matthew; Liu, Zhening; Le, James; Hanson, Brian E


    The preparation of a variety of sulfonated carbons and their use in the esterification of oleic acid is reported. All sulfonated materials show some loss in activity associated with the leaching of active sites. Exhaustive leaching shows that a finite amount of activity is lost from the carbons in the form of colloids. Fully leached catalysts show no loss in activity upon recycling. The best catalysts; 1, 3, and 6; show initial TOFs of 0.07 s(-1), 0.05 s(-1), and 0.14 s(-1), respectively. These compare favorably with literature values. Significantly, the leachate solutions obtained from catalysts 1, 3, and 6, also show excellent esterification activity. The results of TEM and catalyst poisoning experiments on the leachate solutions associate the catalytic activity of these solutions with carbon colloids. This mechanism for leaching active sites from sulfonated carbons is previously unrecognized.

  5. Experimental Research of Erosion Wear of Modified Epoxy Resin Solid Particle%改性环氧树脂固体颗粒冲蚀磨损试验研究

    王彦平; 龚卓; 王起才


    采用气流挟沙喷射法对改性环氧树脂材料进行固体颗粒冲蚀磨损试验,考查冲蚀速度和角度对其冲蚀磨损的影响,并探讨了其冲蚀磨损机理,对比了相同冲蚀条件下几种材料冲蚀率的大小。实验结果表明,改性环氧树脂材料冲蚀率与冲蚀速度近似呈线性关系;在不同的冲蚀速度下,改性环氧树脂材料的冲蚀率在45°冲蚀时最大,表现出半塑性材料的冲蚀特征;在相同的冲蚀条件下,改性环氧树脂材料冲蚀率是对比材料(如 M30砂浆、水泥石等)冲蚀率的1/16~1/4,适合用作强风沙流环境下混凝土桥梁墩身的防护材料;冲蚀形貌扫描电子显微镜照片表明,冲蚀能量的法向分量使材料表面产生裂纹和破碎,而其切向分量使材料表面产生切削。%Experiments were carried out to study the effects of impingement angle and particle velocity on the solid particle erosion behaviour of modified epoxy resin by sandblast method,and the mechanism of erosion wear was discussed,in addition,the erosion rates for several different materials were compared. Experimental results show that the relationship between erosion rates of modified epoxy resin and wind-sand flow velocity approximates linear relationship. The erosion rates for modified epoxy resin are highest at 45° impingement angle under different velocity,which follows semi-ductile material erosion laws. The erosion rate of modified epoxy resin is approximately 1/16 ~1/4 of the reference materials (such as M30 mortar, cement stone etc.) at the same condition. Therefore,the modified epoxy resin can be used protection material for concrete bridge pier under gobi wind-sand flow environment. The morphologies scanning electron microscope photoes show that the normal component of erosion energy makes to produce cracks and debris,and the tangential component to produce surface cutting.

  6. Dehydration of sorbitol to isosorbide on solid acid catalyst%催化山梨醇脱水制备异山梨醇的固体酸催化剂

    孙鹏; 耿红冉; 李正文; 张小伟; 余定华


    为提高目标产物异山梨醇的产率,考察多种固体酸催化剂催化山梨醇脱水的反应性能.结果表明:催化剂酸性与其催化性能之间有密切联系,酸性较强的H3PO4/Nb2O5催化剂显示出比其他催化剂更优异的催化性能.对磷酸负载量进行优化后,在n(P)/n(Nb)为0.8的H3 PO4/Nb2O5催化剂上得到了100%的山梨醇转化率和63%的异山梨醇选择性.%Dehydration of sorbitol to isosorbide on various solid acids was investigated to improve isosor-bide yield. The results showed that the catalytic performances of solid acids were closely related to their acidities. H3PO4/Nb2O5 catalyst with stronger acidity showed better catalytic performance than other solid acids. The 100% sorbitol conversion and 63% isosorbide selectivity was obtained on H3PO4/Nb2O5 catalyst with n(P)/n(Nb) =0.8.

  7. Polystyrene-supported chloroaluminate ionic liquid as a new heterogeneous Lewis acid catalyst for Knoevenagel condensation

    Kaveh Parvanak Boroujeni; Mina Jafarinasab


    Non-hygroscopic polystyrene-supported chloroaluminate ionic liquid was prepared from the reaction of Merrifield resin with 1-methylimidazole followed by reaction with aluminum chloride.This Lewis acidic ionic liquid is environmentally friendly heterogeneous catalyst for the Knoevenagel condensation of aromatic and aliphatic aldehydes with ethyl cyanoacetate.The catalyst is stable (as a bench top catalyst) and reusable.

  8. Synthesis and Thermal Properties of a Novel Nitrogen-containing Epoxy Resin

    Xing Hong ZHANG; Hong Mei WAN; Yu Qin MIN; Zuo FANG; Guo Rong QI


    A new nitrogen-containing epoxy resin (XT resin) was synthesized from chain extension of xylenephenolformaldehyde resin (XPF) and triglycidyl isocyanurate (TGIC) in the presence of base catalyst. FT-IR and 1H-NMR analysis confirmed the chemical structure of XT resin. It was cured with dicyandiamide (DICY) and diaminodiphenyl sulfone (DDS). Dynamic mechanical analysis (DMA) results showed that the introduction of triazine ring provides epoxy polymer with good thermal stability. Furthermore, high char yields at 800℃ in thermogravimetric (TGA)analysis indicated that XT resin had potential flame retardance.

  9. Direct asymmetric aldol reaction using MBHA resin-supported peptide containing L-proline unit

    Liang Zhang; Wen Bo Ding; Yong Ping Yu; Hong Bin Zou


    MBHA resin-supported tripeptide catalyst system containing L-proline unit has been developed for use in the direct asymmetric aldol reaction of acetone and aldehydes,which afford the corresponding products with satisfactory isolated yields and enantiomeric excesses.

  10. Functionalization of zeolitic cavities: grafting NH2 groups in framework T sites of B-SSZ-13--a way to obtain basic solids catalysts?

    Regli, Laura; Bordiga, Silvia; Busco, Claudia; Prestipino, Carmelo; Ugliengo, Piero; Zecchina, Adriano; Lamberti, Carlo


    Insertion of B atoms into an Al-free zeolitic framework with CHA topology results in the formation of B-SSZ-13 zeotype with Si/B = 11. B K-edge NEXAFS testifies that B forms [B(OSi)4] units in a Td-like geometry (sp3-hybridized B atoms). According to B K-edge NEXAFS and IR, template burning results in the formation of [B(OSi)3] units in a D3h-like geometry (sp2-hybridized B atoms) with a break of a B-O-Si bond and the formation of a Si-OH group. The activated material contains B(III) Lewis acid centers able to specifically coordinate bases like NH3. Such [B(OSi)3] units are reactive toward ammonia, resulting in the formation of B-NH2 surface functionality inside the pores of B-SSZ-13 already under mild conditions, i.e., 35 mbar of NH3 at 373 K for 30 min and without crystallinity degradation. A minor fraction of Si-NH2 cannot be excluded owing to the presence of two IR doublets at 3500 and 3430 cm-1 and at 1600 and 1550 cm-1. Ab initio B3LYP/6-31+G(d,p) calculations on a cluster model, supported by a single-point MP2 on B3LYP/6-31+G(D,P) optimized structures, found the break by NH3 of a B-O-Si bond of the [B(OSi)3] unit with formation of [SiOH] and [H2N-B(OSi)2] species to be energetically favored. Comparison between experimental and computed frequency shifts shows them to be in semiquantitative agreement. The high stability of the B-NH2 surface functionality is probed by N K-edge NEXAFS spectra collected under UHV conditions. These findings can open a new route in the preparation of shape selective solid basic catalysts.

  11. 固体催化剂催化牛油制取生物柴油工艺优化%Optimization of transesterification of beef tallow for biodiesel production catalyzed by solid catalysts

    赵昕宇; 徐桂转; 余泳昌; 延晓斌; 张百良


      利用固体催化剂催化废弃动物油脂制取生物柴油可以实现催化剂的重复利用、降低原料成本,从而提高生物柴油的市场竞争力。该文以牛油为原料,在自制固体催化剂Cs2O/γ-Al2O3的催化作用下与甲醇酯交换反应制备生物柴油。采用响应面法对反应过程进行了优化,试验考察了醇油摩尔比、催化剂用量、反应时间和反应温度等操作条件对酯交换反应的影响,并得到了最优反应条件,即反应温度66℃,醇油摩尔比10.5:1,催化剂用量5.3%,反应时间120 min,生物柴油的酯交换率达到95.5%。反应后固体催化剂在400℃下灼烧4 h后可以重复利用,重复利用8次后酯交换率下降不到6%。研究结果将为固体催化剂催化废弃动物油脂制取生物柴油的连续和产业化生产提供试验基础,为提高生物柴油的市场竞争力提供参考。%The production of biodiesel from abandoned animal fat catalyzed by solid catalysts can realize the catalysts reutilization, decrease the cost of raw materials, thus enhancing the market competitiveness of biodiesel. The transesterification reaction of beef tallow and methanol to product biodiesel using Cs2O/γ-Al2O3 as solid catalyst was studied in this study. Response surface methodology and Box-Behnken experimental design were employed to optimize the reaction conditions. The variables of the molar ratio of methanol to oil, catalyst amount, reaction time and reaction temperature were investigated, and the optimum conditions were obtained:molar ratio of methanol to oil 10.5:1, catalyst amount 5.3%(based on the weight of oil), reaction time 120 min, reaction temperature 66℃. Under this optimum reaction conditions, the biodiesel yield was 95.5%. The collected catalyst can be reused after being calcined for 4 h at 400℃ and the biodiesel yields decreased less than 6%after the catalyst being reused for eight cycles in the repeated experiments

  12. Highly Durable Catalysts for Ignition of Advanced Monopropellants Project

    National Aeronautics and Space Administration — Monopropellants are readily ignited or decomposed over a bed of solid catalyst. A serious limitation of existing catalysts in the ignition of advanced...

  13. 碳基固体酸催化剂加压催化合成生物柴油%Synthesis of biodiesel using carbon-based solid acid catalyst under pressure

    司展; 蒋剑春; 王奎; 徐俊明


    Due to the environmental pollution caused by the widely use of and the depletion of fossil energy resources, the search for renewable energy has gained worldwide attention. Biodiesel has been considered as an alternativeto conventional fuels, because it is biodegradable and has high cetane number, low aromatic hydrocarbon content and excellent lubrication performance. Traditionally, the catalysts used for the esterification of inedible oil into biodiesel are liquid acids such as sulfuric acid, which is corrosive and difficult to reprocess. To alleviate these problems, a carbon-based solid acid catalyst was developed by the sulfonation of incompletely carbonized cellulose. The cellulose was heated at an 500℃ under N2 flow about 11 hrs to produce incomplete carbonization. The resulting material with 4 g was then ground to powders and heated in 50mL of concentrated H2SO4 (98%) under N2 flow to introduce SO3H into the aromatic carbon rings. The catalyst was characterized by a series of measurements. The layer structure was found from the Scanning Electron Microscope (SEM) image of the prepared carbon material. The BET result showed the catalyst had no pore structure on the SEM image. The powder X-ray diffraction (XRD) pattern of carbon material after the sulfonation showed broad and weak diffraction peaks attributable to amorphous carbon composed of aromatic carbon sheets oriented in a considerably random fashion. The temperature programmed desorption of NH3 (NH3-TPD) profiles showed that the catalyst had two distinct desorption peaks from 100 to 300℃and 750 to 800℃that were assigned to two types of acid sites. The low and high temperature peaks were corresponded to the weak and strong acid sites, respectively. The catalytic performance of the carbon-based solid acid catalyst for the synthesis of biodiesel was investigated via the esterification of palmitic acid and methanol. The effects of reaction conditions (molar ratio of methanol to palmitic acid, reaction

  14. Homogeneous catalysts

    Chadwick, John C; Freixa, Zoraida; van Leeuwen, Piet W N M


    This first book to illuminate this important aspect of chemical synthesis improves the lifetime of catalysts, thus reducing material and saving energy, costs and waste.The international panel of expert authors describes the studies that have been conducted concerning the way homogeneous catalysts decompose, and the differences between homogeneous and heterogeneous catalysts. The result is a ready reference for organic, catalytic, polymer and complex chemists, as well as those working in industry and with/on organometallics.

  15. Petroleum Resins: Separation, Character, and Role in Petroleum

    Andersen, Simon Ivar; Speight, James


    In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes are precipi......In petroleum science, the term resin generally implies material that has been eluted from various solid adsorbents, whereas the term maltenes (or petrolenes) indicates a mixture of the resins and oils obtained as filtrates from the asphaltene precipitation. Thus, after the asphaltenes...... are precipitated, adsorbents are added to the n-pentane solutions of the resins and oils, by which process the resins are adsorbed and subsequently recovered by the use of a more polar solvent, and the oils remain in solution. The resin fraction plays an important role in the stability of petroleum and prevents...... of the fact that the resin fraction is extremely important to the stability of petroleum, there is surprisingly little work reported on the characteristics of the resins. This article summarizes the work that has been carried out in determining the character and properties of the resin constituents...

  16. Gas-solid catalytic reactions over ruthenium-based catalysts%钌基催化剂催化的气固相反应

    施文博; 刘霄龙; 曾俊淋; 王健; 魏耀东; 朱廷钰


    防止高温焙烧导致催化剂烧结.对于 HCl氧化虽然研究较少,但是 Over等人对 HCl氧化机理进行了深入研究,并且日本住友化工设计的 Ru基催化剂已经商业化. Ru基催化剂可以有效降低甲烷部分氧化的反应温度和压力,并具有高的选择性和稳定性,避免副产物生成.现有催化系统以及新型催化剂开发仍面临诸多挑战,例如:对于单一 VOC氧化过程和多元 VOCs催化氧化的机理和动力学需要进一步研究;对于氨合成需要寻求具有高电导率的载体,从而将电子快速转移到 Ru颗粒表面,使得氨合成在更低温度下进行;为了避免副产物生成,需确保新型 Ru基催化剂上PROX和甲烷部分氧化在低温低压条件下进行; Ru基催化剂理化性质对活性的影响以及失活等问题需要进一步研究.%Ruthenium (Ru)‐based catalysts are widely employed in several types of gas‐solid reactions because of their high catalytic activities. This review provides theoretical research on Ru‐based catalysts and an analysis of their basic properties and oxidation behavior. There is particular emphasis on Ru‐catalyzed gas‐solid catalytic reactions, including the catalytic oxidation of VOCs, preferential oxidation of CO, synthesis of ammonia, oxidation of HCl and partial oxidation of CH4. Recent litera‐ture on catalysis is summarized and compared. Finally, we describe current challenges in the field and propose approaches for future development of Ru‐based catalysts.


    Zhen-zhong Yang


    In this review,our recent work in phase inversion emulsification (PIE)for polymer(especially epoxy resin) waterborne dispersions is summarized.Based on experimental results about PIE process,the physical model is proposed which Can guide the synthesis of the waterborne dispersions such as polymer/nanoparticle composite dispersion.In the presence of a latent curing catalyst,PIE can give a crosslinkable epoxy resin waterborne dispersion.The dispersions can form cured transparent coatings with some unique properties such as UV shielding.They are promising in functional coatings,waterborne resin matrices for composites,and sizing for high performance fibers.

  18. Preparation of Pd-Cu Bimetal Catalyst Loaded on Ion Exchange Resin and its Catalytic Denitrification for Water Containing Nitrate%离子交换树脂负载Pd-Cu双金属催化剂的制备及其对硝酸盐的催化脱除作用

    高建峰; 徐春彦; 高保娇; 庄源益


      The loading-type Pd-Cu bimetal catalyst was prepared using anion exchange resin (AIER) as carrier and complex reagent EDTA as an intermedium. The as-prepared catalyst was used in reduction of nitrate in water to remove nitrate using H2 as reductant. The effects of the composition of bimetal, the property of the carrier and the presence of NaCl on the denitrification were investigated. The results showed that the metal ions (Cu2+and Pd2+) can be combined onto resin surface by the strong adsorption of AIER towards EDTA and the strong chelation of EDTA for metal ions. Via reduction of hydrazine hydrate for the metal ions, the loading-type catalyst Pd-Cu/AIER with high bimetal capacity and firm combination property were obtained. For the aqueous solution mere containing nitrate, NO3- only was reduced into NH4+ by the catalysis of Pd-Cu/ AIER. In the presence of higher concentration NaCl, the reduction of NO3-into N2 could be accelerated greatly. The activity and selectivity of the catalyst prepared is poorer if the weak alkaline anion exchange resins were used.%  采用阴离子交换树脂(AIER)为载体,以络合剂EDTA为媒介物,制备了Pd-Cu双金属负载性型催化剂;以H2为还原剂,将催化剂应用于水介质中NO3-还原为N2的脱除反应;考察了双金属催化剂组成、载体阴离子交换树脂的性质及水介质中NaCl存在对还原脱除反应的影响规律.研究结果表明,凭借阴离子交换树脂对EDTA强烈的吸附作用及EDTA对金属离子的强螯合作用,可将大量的金属离子(Cu2+与Pd2+)结合到树脂表面,再通过水合肼的还原作用,可制得金属负载量高且结合程度牢的双金属负载性型催化剂Pd-Cu/AIER.在单纯含有硝酸盐的水溶液中,在催化剂Pd-Cu/AIER的作用下,NO3-只能被还原为NH4+离子,不能还原为N2;水介质中大量氯离子的存在,能大大促进NO3-转变为N2的还原反应;载体阴离子交换树脂的碱性越弱,最终制得的催化剂活性与选择性越差.

  19. Review: Resin Composite Filling

    Chan, Keith H. S.; Mai, Yanjie; Kim, Harry; Tong, Keith C. T.; Ng, Desmond; Hsiao, Jimmy C. M.


    The leading cause of oral pain and tooth loss is from caries and their treatment include restoration using amalgam, resin, porcelain and gold, endodontic therapy and extraction. Resin composite restorations have grown popular over the last half a century because it can take shades more similar to enamel. Here, we discuss the history and use of resin, comparison between amalgam and resin, clinical procedures involved and finishing and polishing techniques for resin restoration. Although resin composite has aesthetic advantages over amalgam, one of the major disadvantage include polymerization shrinkage and future research is needed on reaction kinetics and viscoelastic behaviour to minimize shrinkage stress.

  20. Self-encoding resin beads of combinatorial library screening

    Lei, Du; Zhao, Yuandi; Cheng, Tongsheng; Zeng, Shaoqun; Luo, Qingming


    The latest self-encoding resin bead is a novel technology for solid phase synthesis combinatorial library screening. A new encode-positional deconvolution strategy which was based on that technology been illustrated compared with positional scanning and iterative strategies. The self-encoding resin beads technology provides an efficient method for improving the high-throughput screening of combinatorial library.

  1. Studies concerning the anion ex-change resins catalyzed esterification of epichlorohydrin with organic acids

    E.I. Muresan


    Full Text Available The paper studies the esterification of carboxylic acids with epichlorohydrin over two macroporous strong base anion exchange resins with different polymer matrix. For both resins, the influence of reaction parameters (temperature, catalyst loading, molar ratio on the reaction rate and the yields of the two isomeric esters were investigated.

  2. Nanopore and nanoparticle catalysts.

    Thomas, J M; Raja, R


    The design, atomic characterization, performance, and relevance to clean technology of two distinct categories of new nanocatalysts are described and interpreted. Exceptional molecular selectivity and high activity are exhibited by these catalysts. The first category consists of extended, crystallographically ordered inorganic solids possessing nanopores (apertures, cages, and channels), the diameters of which fall in the range of about 0.4 to about 1.5 nm, and the second of discrete bimetallic nanoparticles of diameter 1 to 2 nm, distributed more or less uniformly along the inner walls of mesoporous (ca. 3 to 10 nm diameter) silica supports. Using the principles and practices of solid-state and organometallic chemistry and advanced physico-chemical techniques for in situ and ex situ characterization, a variety of powerful new catalysts has been evolved. Apart from those that, inter alia, simulate the behavior of enzymes in their specificity, shape selectivity, regio-selectivity, and ability to function under ambient conditions, many of these new nanocatalysts are also viable as agents for effecting commercially significant processes in a clean, benign, solvent-free, single-step fashion. In particular, a bifunctional, molecular sieve nanopore catalyst is described that converts cyclohexanone in air and ammonia to its oxime and caprolactam, and a bimetallic nanoparticle catalyst that selectively converts cyclic polyenes into desirable intermediates. Nanocatalysts in the first category are especially effective in facilitating highly selective oxidations in air, and those in the second are well suited to effecting rapid and selective hydrogenations of a range of organic compounds.

  3. Synthesis of novel perfluoroalkylglucosides on zeolite and non-zeolite catalysts.

    Nowicki, Janusz; Mokrzycki, Łukasz; Sulikowski, Bogdan


    Perfluoroalkylglucosides comprise a very important class of fluorine-containing surfactants. These compounds can be synthesized by using the Fisher reaction, starting directly from glucose and the required perfluoroalcohols. We wish to report on the use of zeolite catalysts of different structure and composition for the synthesis of perfluoroalkylglucosides when using glucose and 1-octafluoropentanol as substrates. Zeolites of different pore architecture have been chosen (ZSM-5, ZSM-12, MCM-22 and Beta). Zeolites were characterized by XRD, nitrogen sorption, scanning electron microscopy (SEM) and solid-state 27Al MAS NMR spectroscopy. The activity of the zeolite catalysts in the glycosidation reaction was studied in a batch reactor at 100 °C below atmospheric pressure. The performance of zeolites was compared to other catalysts, an ion-exchange resin (Purolite) and a montmorillonite-type layered aluminosilicate. The catalytic performance of zeolite Beta was the highest among the zeolites studied and the results were comparable to those obtained over Purolite and montmorillonite type catalysts.

  4. Acetylene-chromene terminated resins as high temperature thermosets

    Godschalx, J. P.; Inbasekaran, M. N.; Bartos, B. R.; Scheck, D. M.; Laman, S. A.


    A novel phase transfer catalyzed process for the preparation of propargyl ethers has been developed. The propargyl ethers serve as precursors to a new class of thermosetting resins called acetylene-chromene terminated (ACT) resins. Heat treatment of a solution of propargyl ethers with various catalysts, followed by removal of solvent leads to the ACT resins via partial conversion of the propargyl ether groups to chromenes. This process reduces the energy content of the resin systems and reduces the amount of shrinkage found during cure. Due to the presence of the solvent the process is safe and gives rise to low viscosity products suitable for resin transfer molding and filament winding type applications. Due to the high glass transition temperature, high modulus, and low moisture uptake the cured resins display better than 232 C/wet performance. The thermal stability of the ACT resins in air at 204 C is superior to that of conventional bismaleimide resins. The resins also display excellent electrical properties.

  5. Acetylene-chromene terminated resins as high temperature thermosets

    Godschalx, J. P.; Inbasekaran, M. N.; Bartos, B. R.; Scheck, D. M.; Laman, S. A.


    A novel phase transfer catalyzed process for the preparation of propargyl ethers has been developed. The propargyl ethers serve as precursors to a new class of thermosetting resins called acetylene-chromene terminated (ACT) resins. Heat treatment of a solution of propargyl ethers with various catalysts, followed by removal of solvent leads to the ACT resins via partial conversion of the propargyl ether groups to chromenes. This process reduces the energy content of the resin systems and reduces the amount of shrinkage found during cure. Due to the presence of the solvent the process is safe and gives rise to low viscosity products suitable for resin transfer molding and filament winding type applications. Due to the high glass transition temperature, high modulus, and low moisture uptake the cured resins display better than 232 C/wet performance. The thermal stability of the ACT resins in air at 204 C is superior to that of conventional bismaleimide resins. The resins also display excellent electrical properties.

  6. Study on binder system of CO2-cured phenol-formaldehyde resin used in foundry

    Liu Weihua; Li Yingmin; Qu Xueliang; Liu Xiuling


    A new aqueous alkaline resol phenol-formaldehyde resin has been prepared from phenol and formaldehyde using NaOH as catalyst;the optimum synthetic process has been determined.With addition of some cross-linking agents,after passing carbon dioxide gas through the resin bonded sand,high as-gassed strength and 24 h strength are achieved.The bonding bridge of the resin bonded sand fracture has been analyzed by using SEM.

  7. Application of resin system for sand consolidation, mud-loss control, and channel repairing

    Wasnik, A.; Mete, S.; Ghosh, B. [Maharashtra Inst. of Technology (India)


    Sand production is one of the major challenges facing oil well operators. A technique for sand consolidation and channel repairing with a resin system was described along with a methodology for placing a chemical casing during or after drilling a shale zone that is prone to caving. The methodology is intended to facilitate drilling with reduced mud weight, without reducing the hole size. The resin comprises a mixture of elastomers UF, MF and a suitable plasticizer to impart flexibility and impact resistance. The resin system includes both the resin and a hardener which is a mixture of 2 mild Lewis acids to control curing time. A special additive can be used to enhance surface bonding between the sand and resin. Experiments were then performed to examine the efficiency of resin (Asmid 603) with 7 different chemicals and resin Furmel 301 with Furmel catalyst as a curing modifier. The best combination for sand consolidation and chemical casing was found to be resin Asmid 603 with 0.6 per cent o-phosphoric acid at 80 degrees C and Furmel 301 with 2.5 per cent Furmel catalyst and CFNL with 0.6 per cent o-phosphoric acid. When this combination was used, the permeability was found to be nearly zero after consolidation of resin. The newly developed resin system costs one-third that of epoxy resins. Since it is water soluble, it is also easy to handle and environmentally sound. 15 refs., 2 tabs., 6 figs.

  8. Color test for selective detection of secondary amines on resin and in solution

    Boas, Ulrik; Mirsharghi, Sahar


    Resins for solid-phase synthesis give orange to red-brown resin beads selectively when secondary amines are present on the resin when treated with a solution of acetaldehyde and an Fmoc-amino acid in NMP. The method shows good specificity and gives colorless beads when exposed to a variety of oth...

  9. Research progress of high solids and low viscosity water-borne hydroxyl acrylic resin%高固低黏羟基丙烯酸树脂水分散体研究进展

    袁腾; 王锋; 胡剑青; 涂伟萍; 周显宏


    介绍了羟基丙烯酸树脂的水分散规律及原理、溶液聚合的溶剂及水分散的助溶剂的选用方法。综述了制备高固体分低黏度羟基丙烯酸树脂水分散体的研究进展,主要包括提高聚合温度、选用过氧化二叔戊基等引发剂合成低分子量低交联度聚合物;合成核壳结构或以叔碳酸缩水甘油酯、叔碳酸乙烯酯、甲基丙烯酸苄酯、(甲基)丙烯酸异冰片酯、甲基丙烯酸环己酯、甲基丙烯酸叔丁基环己酯等功能单体合成枝化结构羟基丙烯酸树脂;采用多步聚合工艺制备具有特殊结构或较低分子量的共聚物,并对其原理进行了简要分析。最后总结了羟基丙烯酸树脂水分散体目前存在的一些问题,主要包括耐水耐溶剂性、稳定性、成膜性等;并对解决上述一系列问题的研究方向进行了展望,主要包括树脂结构、成膜机理、涂料配方等。%This paper introduces the principles of dispersion of hydroxyl acrylic resin in water and the selection of polymerization solvent and the co-solvent of water dispersion.It summarizes the latest development in preparing high solids and low viscosity water-borne hydroxyl acrylic resin,including higher temperature of polymerization,choosing peroxide di-tert-pentyl to synthesize low molecular weight and low-degree crosslinking polymers,synthesizing core-shell structure,or branching structure hydroxyl acrylic resin from glycidyl versatate,vinyl versatate,methacrylic acid benzyl ester,(meth) acrylate isobornyl ester,methacrylic acid cyclohexyl ester,methyl acrylic acid tert-butyl cyclohexyl ester and other functional monomers,preparing a specially-structured or low-molecular weight copolymer by using multi-step polymerization technology(with a brief analysis of its principle).In conclusion,this article describes some existing problems about hydroxy acrylic resin aqueous dispersion,including water resistance,solvent resistance,stability,and film


    M. Rafizadeh; H. Ghasemi; V. Haddadi-Asl


    Due to its mechanical properties and ease of use, vinyl ester resin is enjoying increasing consideration. This resin normally is produced by reaction between epoxy resin and unsaturated carboxylic acid. In the present study, bis-phenol A based epoxy resin and methacrylic acid was used to produce vinyl ester resin. The reaction was conducted under both stoichiometric and non-stoichiometric conditions in the presence of triphenylphosphine as catalyst. The stoichiometric and non-stoichiometric experiments were conducted at 95, 100, 105 and 110℃ and at 90 and 95℃, respectively. The first order rate equation and mechanism based rate equation were examined. Parameters are evaluated by least square method. A comparison of mechanism based rate equation and experimental data show an excellent agreement. Finally, Arrhenius equation and activation energy were presented.

  11. An eco-friendly N-sulfonylation of amines using stable and reusable Zn-Al-hydrotalcite solid base catalyst under ultrasound irradiation.

    Mokhtar, M; Saleh, T S; Ahmed, N S; Al-Thabaiti, S A; Al-Shareef, R A


    Synthetic nanosized Zn-Al-hydrotalcite (Zn-Al-HT) with 20 nm crystallite size and 61 m(2)/g BET-surface area is found to be a mild and efficient catalyst for N-sulfonylation of amines in quantitative yields under ultrasound irradiation. Exclusive synthesis of sulfonamides, using Zn-Al-HT, under ultrasound irradiation, was realized by compatible basic sites of catalyst used. The products were isolated after simple work-up in high yields and purity. Copyright © 2010 Elsevier B.V. All rights reserved.

  12. Solid Base Catalysis

    Ono, Yoshio


    The importance of solid base catalysts has come to be recognized for their environmentally benign qualities, and much significant progress has been made over the past two decades in catalytic materials and solid base-catalyzed reactions. The book is focused on the solid base. Because of the advantages over liquid bases, the use of solid base catalysts in organic synthesis is expanding. Solid bases are easier to dispose than liquid bases, separation and recovery of products, catalysts and solvents are less difficult, and they are non-corrosive. Furthermore, base-catalyzed reactions can be performed without using solvents and even in the gas phase, opening up more possibilities for discovering novel reaction systems. Using numerous examples, the present volume describes the remarkable role solid base catalysis can play, given the ever increasing worldwide importance of "green" chemistry. The reader will obtain an overall view of solid base catalysis and gain insight into the versatility of the reactions to whic...

  13. Synthesis of Organic Compounds over Selected Types of Catalysts

    Omar Mohamed Saad Ismail


    Full Text Available This study provides an overview for the utilization of different catalytic material in the synthesis of organic compounds for important reactions such as heck reaction, aldol reaction, Diels- Alder and other reactions. Comparisons between multiple catalysts for the same reaction and justifications for developing new catalyzed materials are discussed. The following topics are introduced in this work; (1 solid base catalysts, (2 clay catalysts, (3 palladium catalysts, and (4 catalysts to produce organic compound from CO2. The features of these catalysts a long with the conjugated reactions and their selectivity are explained in details, also, some alternatives for toxic or polluting catalysts used in industry are suggested.

  14. Synthesis and Mechanism of Metal-Mediated Polymerization of Phenolic Resins

    Zhao Yi


    Full Text Available Phenol-formaldehyde (PF resin is a high performance adhesive, but has not been widely developed due to its slow curing rate and high curing temperature. To accelerate the curing rate and to lower the curing temperature of PF resin, four types of metal-mediated catalysts were employed in the synthesis of PF resin; namely, barium hydroxide (Ba(OH2, sodium carbonate (Na2CO3, lithium hydroxide (LiOH, and zinc acetate ((CH3COO2Zn. The cure-acceleration effects of these catalysts on the properties of PF resins were measured, and the chemical structures of the PF resins accelerated with the catalysts were investigated by using Fourier transform infrared (FT-IR spectroscopy and quantitative liquid carbon-13 nuclear magnetic resonance (13C NMR. The results showed that the accelerated efficiency of these catalysts to PF resin could be ordered in the following sequence: Na2CO3 > (CH3COO2Zn > Ba(OH2 > LiOH. The catalysts (CH3COO2Zn and Na2CO3 increased the reaction activity of the phenol ortho position and the condensation reaction of ortho methylol. The accelerating mechanism of (CH3COO2Zn on PF resin is probably different from that of Na2CO3, which can be confirmed by the differences in the differential thermogravimetric (DTG curve and thermogravimetric (TG data. Compared to the Na2CO3-accelerated PF resin, the (CH3COO2Zn-accelerated PF resin showed different peaks in the DTG curve and higher weight residues. In the synthesis process, the catalyst (CH3COO2Zn may form chelating compounds (containing a metal-ligand bond, which can promote the linkage of formaldehyde to the phenolic hydroxyl ortho position.

  15. Profiling and Preparation of Metabolites from Pyragrel in Human Urine by Online Solid-Phase Extraction Coupled with High Performance Liquid Chromatography Tandem Mass Spectrometry Followed by a Macroporous Resin-Based Purification Approach.

    Zhao, Xin; Jiang, Jingjing; Yang, Guang; Huang, Jie; Yang, Guoping; He, Guangwei; Chu, Zhaoxing; Hang, Taijun; Fan, Guorong


    Pyragrel, a new anticoagulant drug, is derived from the molecular combination of ligustrazine and ferulic acid. Pyragrel showed significant inhibitory activity against platelet aggregation induced by adenosine diphosphate (ADP), and had been approved for a phase I clinical trial by CFDA. To characterize the metabolites of Pyragrel in human urine after intravenous administration, a reliable online solid-phase extraction couple with high performance liquid chromatography tandem mass spectrometry (online SPE-HPLC-MS(n)) method was conceived and applied. Five metabolites were detected and tentatively identified, which suggested that the major metabolic pathways of Pyragrel in human were double-bond reduction, double-bond oxidation, and then followed by glucuronide conjugation. Two main metabolites were then prepared using β-glucuronide hydrolysis and macroporous resin purification approach followed by preparative high-performance liquid chromatography (PHPLC) method, with their structures confirmed on the basis of nuclear magnetic resonance (NMR) data. This study provided information for the further study of the metabolism and excretion of Pyragrel.

  16. The role of nano-Ni catalyst in MgH2 obtained by reactive mechanical milling method for solid hydrogen storage application

    Jalil, Zulkarnain; Rahwanto, Adi; Handoko, Erfan; Mustanir


    Magnesium (Mg) is regarded as one of the candidate material for absorbing hydrogen, because theoretically, has the ability to absorb hydrogen in the large quantities (7.6 wt%). However, Mg has shortage, namely its kinetic reaction is very slow, it takes time to absorb hydrogen at least 60 minutes with very high operating temperatures (300-400°C). The aim of this study is to improve the hydrogen desorption temperature of Mg-based hydrogen storage material. In this work, we used nano-nickel (Ni) as catalyst in MgH2 and obtained by reactive mechanical milling method. The duration of milling was done in 2 hours (soft milling) with the 2 mol% Ni catalyst and milled under hydrogen atmosphere (10 bar). As the results, small amount of 2 mol% Ni in nanometer scale acts as a suitable catalyst for improvement the kinetics of MgH2 which could absorp 5.5 wt% of hydrogen within 10 minutes at 300°C. It is obvious that small amount has much better as catalyst in nanoparticle size and at the same time allowed to reduce the milling process in short time.

  17. Synthesis of bio-based methacrylic acid by decarboxylation of itaconic acid and citric acid catalyzed by solid transition-metal catalysts

    Notre, le J.E.L.; Witte-van Dijk, S.C.M.; Haveren, van J.; Scott, E.L.; Sanders, J.P.M.


    Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84%) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200–2508C without any external added pressure, conditions

  18. Synthesis of bio-based methacrylic acid by decarboxylation of itaconic acid and citric acid catalyzed by solid transition-metal catalysts

    Notre, le J.E.L.; Witte-van Dijk, S.C.M.; Haveren, van J.; Scott, E.L.; Sanders, J.P.M.


    Methacrylic acid, an important monomer for the plastics industry, was obtained in high selectivity (up to 84%) by the decarboxylation of itaconic acid using heterogeneous catalysts based on Pd, Pt and Ru. The reaction takes place in water at 200–2508C without any external added pressure, conditions

  19. Method of performing sugar dehydration and catalyst treatment

    Hu, Jianli [Kennewick, WA; Holladay, Johnathan E [Kennewick, WA; Zhang, Xinjie [Burlington, MA; Wang, Yong [Richland, WA


    The invention includes a method of treating a solid acid catalyst. After exposing the catalyst to a mixture containing a sugar alcohol, the catalyst is washed with an organic solvent and is then exposed to a second reaction mixture. The invention includes a process for production of anhydrosugar alcohol. A solid acid catalyst is provided to convert sugar alcohol in a first sample to an anhydrosugar alcohol. The catalyst is then washed with an organic solvent and is subsequently utilized to expose a second sample. The invention includes a method for selective production of an anhydrosugar. A solid acid catalyst is provided within a reactor and anhydrosugar alcohol is formed by flowing a starting sugar alcohol into the reactor. The acid catalyst is then exposed to an organic solvent which allows a greater amount of additional anhydrosugar to be produced than would occur without exposing the acid catalyst to the organic solvent.

  20. Resin phantoms as skin simulating layers

    Karsten, AE


    Full Text Available on the efficiency of Photodynamic Therapy (PDT) treatment. Two resin based solid phantoms were prepared to simulate two different skin types. Cells were prepared and PDT treatment were done on cells with and without the phantoms, by keeping the total dose delivered...

  1. Fundamental studies of the mechanism of catalytic reactions with catalysts effective in the gasification of carbon solids and the oxidative coupling of methane. Quarterly report, October 1, 1994--December 31, 1994

    Iglesia, E.; Perry, D.L.; Heinemann, H.


    This report describes research on the oxidative coupling of methane and catalysts involved in coal gasification. Topics include methane pyrolysis and catalysts, and magnetic properties of the coal gasification catalyst Ca-Ni-K-O system.

  2. 高固体含量线性酚醛树脂的固化动力学%Curing Kinetics of Novolac-Type Phenolic Resin with High Solid Content

    理莎莎; 齐暑华; 刘乃亮; 曹鹏


    合成了高固体含量(〉85%)的线性酚醛树脂,经凝胶渗透色谱/多角度激光光散射(SEC/MALLS)联用仪测定其数均分子量为1577,且分子量分布范围较窄,-Mw/-Mn仅为1.127。采用差示扫描量热(DSC)分析技术在50℃~300℃温度范围内,以不同的升温速率(2.5℃/min、5℃/min、7.5℃/min和10℃/min)研究了该酚醛树脂的固化反应过程。结果表明,该高固体含量线性酚醛树脂的凝胶化温度Tgel=110.61℃,固化温度Tcure=129.14℃,后处理温度Ttreat=146.96℃;根据Kissinger方程、Ozawa方程和Crane方程以及n级动力学模型确定该树脂的固化动力学方程为dα(t)/dt=2.09×1017(1-α)0.95exp(-2.10235×104/T)。%Novolac-type resin with high solid content(85%) was synthesized,of which number average molecular weight is 1577 and distribution is narrow.The curing process was studied by differential scanning calorimetry(DSC) at different heating rates of 2.5 ℃/min,5 ℃/min,7.5 and 10 ℃/min between 50 ℃~300 ℃.The gelation temperature,curing temperature and post processing temperature of the resin are 136.68 ℃,163.16 ℃ and 197.39 ℃ respectively.According to Kissinger equation,Ozawa equation,Crane equation and the n-level kinetic model,the curing kinetic equation is dα(t)/dt=2.09×1017(1-α)0.95exp(-210235×103/T).

  3. 凹凸棒黏土负载型固体酸催化合成乙酰水杨酸%Synthesis of Acetylsalicylic Acid over Attapulgite Supported Solid Acid Catalyst

    吴洁; 蒋金龙; 钱晓敏


    Attapulgite (ATP) supported H+ and AlCl3 solid acid catalysts (H+/ATP and AlCl3/ATP) were prepared and their catalytic activities for synthesis of acetylsalicylic acid (AA) from salicylic acid and acetic anhydride were compared with the free acids.The results suggested that the solid acid catalysts exhibited higher activity than those of the free acids, especially AlCl3/ATP catalyst.Under the optimum conditions of AlCl3/ATP catalyst mass fraction 5% (based on salicylic acid), reaction temperature 80 ℃, reaction time 30 min and mole ratio of acetic anhydride to salicylic acid 2.0, the yield and the purity of AA reached 92.5% and 99.5% respectively.The synthesized AA was characterized by means of FTIR and 1H NMR.The AA yield still reached 89.2% after it was regenerated and reused for 5 times.%以凹凸棒黏土(ATP)为载体,制备了负载H+和AlCl3的固体酸催化剂(分别标记为H+/ATP,AlCl3/ATP),比较了负载前后催化剂对乙酰水杨酸合成反应的催化活性.实验结果表明,固体酸催化剂的活性高于游离酸催化剂,其中AlCl3/ATP催化剂的活性最高.以AlCl3/ATP为催化剂催化合成乙酰水杨酸的最佳工艺条件为:催化剂用量为5%(基于水杨酸质量),n(乙酸酐):n(水杨酸)=2.0,反应温度80℃,反应时间30 min;在此条件下,乙酰水杨酸收率达92.5%,纯度为99.5%.用FTIR和1H NMR表征了产物结构.AlCl3/ATP催化剂经活化再生重复使用5次后,乙酰水杨酸收率仍可达89.2%,表明AlCl3/ATP催化剂具有一定的稳定性,可实现再生利用.

  4. Ni-loaded nanocrystalline ceria-zirconia solid solutions prepared via modified Pechini route as stable to coking catalysts of CH4 dry reforming

    Sadykov Vladislav A.


    Full Text Available Mixed nanocrystalline Ce-Zr-O oxides (Ce/Zr = 1 or 7/3 were prepared by modified Pechini route using ethylene glycol solutions of metal salts. Detailed characterization of their real structure and surface properties by X-ray diffraction on synchrotron radiation with the full-profile Rietveld analysis, high resolution electron microscopy with elemental analysis, Raman spectroscopy, UV-Vis and X-ray photoelectron spectroscopy revealed a high homogeneity of cations distribution in nanodomains resulting in stabilization of disordered cubic phase. This provides a high dispersion of NiO loaded on these mixed oxides by wet impregnation, a high reactivity and mobility of oxygen in these catalysts and strong interaction of Ni with support in the reduced state. This helps to achieve a high activity and coking stability of developed catalysts in CH4 dry reforming in feeds with CH4 concentration up to 15% and CH4/CO2 ratio =1.

  5. Acetalization of carbonyl compounds with 2,2,4-trimethyl-1,3-pentanedio catalyzed by novel carbon based solid acid catalyst

    Ling Liu; Yuechang Zhao; Shan Gan; Xuezheng Liang; Jianguo Yang; Mingyuan He


    The synthesis of 2, 4-diisopropyl-5,5-dimethyl-1,3-dioxane through the acetalization of isobutyraldehyde with 2, 2,4-trimethyl-1,3-pentanediol (TMPD) catalyzed by the novel carbon based acid was first carried out. High conversion (≥98%) and specific selectivity were obtained using the novel carbon based acid, which kept high activity after it was reused 5 times.Moreover, the catalyst could be used to catalyze the acetalization and ketalization of different aldehydes and ketones with superior yield. The yield of several products was over 90%. The novel heterogeneous catalyst has the distinct advantages of high activity, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the success of the green process greatly.

  6. Mechanistic studies of the methanol-to-olefin process on acidic zeolite catalysts by in situ solid-state NMR-UV/Vis spectroscopy

    Jiang, Yijiao


    Due to the increasing demand for light olefins, the catalytic conversion of methanol-to-olefins (MTO) on acidic zeolite catalysts continues to be an industrially interesting process in heterogeneous catalysis. During the last decades, increasing efforts were made to clarify the mechanism of the MTO process. Recent progress revealed that, in the MTO process, the conversion of an equilibrium mixture of methanol and dimethyl ether (DME) is dominated by a “hydrocarbon pool” route in which methano...

  7. Study of catalytic effect of ammonium molybdate on the bisphthalonitrile resins curing reaction with aromatic amine

    Wen Ting Li; Fang Zuo; Kun Jia; Xiao Bo Liu


    A kind of catalyst, ammonium molybdate was developed in this paper to promote the curing reaction of bisphthalonitrile resins with aromatic amine as curing agent, and the catalytic effect was studied by differential scanning calorimetry (DSC), rheometric measurements and thermogravimetric analysis (TGA). The results indicated that the catalyst could improve the curing rate and increase the curing degree, which could be regulated by the content of the catalyst used in the reaction.

  8. Catalyst mixtures

    Masel, Richard I.; Rosen, Brian A.


    Catalysts that include at least one catalytically active element and one helper catalyst can be used to increase the rate or lower the overpotential of chemical reactions. The helper catalyst can simultaneously act as a director molecule, suppressing undesired reactions and thus increasing selectivity toward the desired reaction. These catalysts can be useful for a variety of chemical reactions including, in particular, the electrochemical conversion of CO.sub.2 or formic acid. The catalysts can also suppress H.sub.2 evolution, permitting electrochemical cell operation at potentials below RHE. Chemical processes and devices using the catalysts are also disclosed, including processes to produce CO, OH.sup.-, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, O.sub.2, H.sub.2, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.

  9. Highly redox-resistant solid oxide fuel cell anode materials based on La-doped SrTiO3 by catalyst impregnation strategy

    Shen, X.; Sasaki, K.


    An anode backbone using 40 wt% (ZrO2)0.89(Sc2O3)0.1(CeO2)0.01 (SSZ)-Sr0.9La0.1TiO3 (SLT) cermet was prepared for SSZ electrolyte-supported SOFC single cells. 15 mgcm-2 Ce0.9Gd0.1O2 (GDC) was impregnated to totally cover the SSZ-SLT anode backbone surface acting as a catalyst, and the cell voltage achieved 0.865 V at 200 mAcm-2 using (La0.75Sr0.25)0.98MnO3 (LSM)-SSZ cathode in 3%-humidified hydrogen fuel at 800 °C. Cell performance was substantially improved from 0.865 V to >0.97 V when 0.03 mgcm-2 Pd or Ni was further incorporated as a secondary catalyst into the anode layer. 50 redox cycles were performed to investigate redox stability of this high performance anode. It was found that even after the 50 redox cycle long-term degradation test, cell voltage at 200 mAcm-2 was retained around 0.94 V, higher than the cell performance using the conventional Ni-SSZ cermet anode. The catalytically-active reaction sites at ceria-Pd or ceria-Ni may account for the excellent performance, and the extremely low metal catalyst concentration prevent serious metal aggregation in achieving excellent redox stability.

  10. Photo-oxidation catalysts

    Pitts, J. Roland; Liu, Ping; Smith, R. Davis


    Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

  11. Solid acid catalysis from fundamentals to applications

    Hattori, Hideshi


    IntroductionTypes of solid acid catalystsAdvantages of solid acid catalysts Historical overviews of solid acid catalystsFuture outlookSolid Acids CatalysisDefinition of acid and base -Brnsted acid and Lewis acid-Acid sites on surfacesAcid strengthRole of acid sites in catalysisBifunctional catalysisPore size effect on catalysis -shape selectivity-Characterization of Solid Acid Catalysts Indicator methodTemperature programmed desorption (TPD) of ammoniaCalorimetry of adsorption of basic moleculesInfrare

  12. 固体碱催化剂KF/Al2O3催化合成乙二醇丁醚%Synthesis of Ethylene Glycol Monobutyl Ether with KF/Al2O3 Solid Base Catalyst

    郭登峰; 刘红; 刘准; 曹惠庆; 赵文; 石兆君


    针对乙二醇丁醚合成中传统催化剂产物后处理工艺复杂、污染环境等缺点,采用浸渍法制备KF/Al2O3负载型固体碱催化剂,催化环氧乙烷(EO)与丁醇反应合成乙二醇丁醚.考察了催化剂前驱体/载体比例、焙烧温度对催化性能的影响.结果表明氟化钾(KF)负载量为30%,焙烧温度为600℃时,催化剂时EO和丁醇反应催化活性最高.对催化剂进行了XRD表征,并采用Hammett指示剂法测定了催化剂的碱强度:pKa>9.3的总碱量为3.0mmol/g催化剂,碱强度(H_)≥18.4,属中等碱强度催化剂.KF/Al2O3固体碱催化剂用于催化合成乙二醇丁醚最佳工艺条件为:反应温度110℃,反应压力0.20~0.30 MPa,催化剂用量为0.5%(m/m),n(BuOH)∶n(EO)为5∶1,反应时间100~120 min,EO转化率达99.47%.%In order to solve the problems that the traditional catalysts are dealt in difficult and polluted environments in ethylene glycol monobutyl ether production, the KF/Al2O3 solid base catalysts are prepared via impregnation method and their catalytic properties for the etherification to synthesize ethylene glycol monobutyl ether from ethylene oxide(EO) and butanol are evaluated.The influences of loading amount of KF over Al2O3 support, calcinate temperature of catalysts are examined.The results indicate that the catalyst possesses the best catalytic activity under the conditions of catalyst calcinate temperature 600 ℃ and 30% of loading amount of KF.The catalysts are characterized by means of X-ray diffraction( XRD)and surface alkalinity are determined by Hammett indicator method.The results show that its base strength is higher than 18.4 and the base amount(pKa>9.3)is 3.0 mmol/g Cat.The optimal etherification condition is as follows: reaction temperature 110℃, pressure O.20 ~0.30 MPa,reaction time 100 ~ 120 min,w(catalyst)= O.5% and n(BuOH) :n( EO)= 5:1.Under such reaction conditions,the conversion of EO reaches 99.47%.

  13. Decomposition studies of filtered slurries using the enhanced comprehensive catalyst

    Wilmarth, W.R.; Crawford, C.L.; Peterson, R.A.


    This study examined decomposition of the soluble phenylborates at elevated temperatures (45 degrees Celsius) to determine the effects of filtering the solid tetraphenylborate, solid sludge and monosodium titanate and spiking additional levels of transition metal catalyst.

  14. Catalysis by nonmetals rules for catalyst selection

    Krylov, Oleg V


    Catalysis by Non-metals: Rules of Catalyst Selection presents the development of scientific principles for the collection of catalysts. It discusses the investigation of the mechanism of chemosorption and catalysis. It addresses a series of properties of solid with catalytic activity. Some of the topics covered in the book are the properties of a solid and catalytic activity in oxidation-reduction reactions; the difference of electronegativities and the effective charges of atoms; the role of d-electrons in the catalytic properties of a solid; the color of solids; and proton-acid and proton-ba

  15. Visbreaking of heavy petroleum oil catalyzed by SO42-/ZrO2 solid super-acid doped with Ni2+ or Sn2+


    SO42-/ZrO2 solid super-acid catalysts (SZ)doped with Ni2+ or Sn2+ (Ni2+/SZ,Sn2+/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field.The visbreaking reactions were carried out at 240℃ and 3-4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 :0.05.The effect of water content on viscosity of heavy petroleum oil was also investigated.Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced for (Sn2+/SZ) with visbreaking rates of 57.7% and 48.9%,respectively.After visbreaking,the saturated hydrocarbon content increased while aromatics,resin,asphaltene,sulfur and nitrogen content decreased.The presence of water was disadvantageous to visbreaking of heavy petroleum oil.


    Jianghua Wang


    Full Text Available Solid nanocatalyst aluminum dodecatungstophosphate (Al0.9H0.3PW12O40, abbreviated as AlPW with nanotube structure was synthesized through a natural cellulose fiber template. The AlPW nanotubes, which are highly water-tolerant and acid-tolerant, can be described as green double acids, as they combine both Brønsted and Lewis acid sites. They have been applied as an efficient nanoheterogeneous catalyst for the preparation of biodiesel from waste cooking oil containing 26.89 wt% high free fatty acids (FFAs and 1% moisture via esterification of FFAs and transesterification of triglycerides in one pot under mild conditions.

  17. Study on Preparation of Isosorbitol Using Solid acid Catalyst%固体酸催化合成异山梨醇的研究



    To prepare isosorbitol by dehydration reaction of sorbitol with p-toluenesulfonic acid as the catalyst, tolu- ene as dehydrating agent. The product quality reached Japanese standards, the yield was 50%.%以对甲苯磺酸为催化剂、甲苯为带水剂,山梨醇脱水制备异山梨醇,产品质量符合日本药典XV质量标准,收率约为50%。

  18. Use of FTIR in the obtention of resins and peptides synthesis in solid phase; Uso da FTIR na obtencao de resinas e na sintese de peptideos em fase solida

    Cespedes, Graziely Ferreira; Vicente, Eduardo Festozo; Cilli, Eduardo Maffud, E-mail: cilli@iq.unesp.b [Universidade Estadual Paulista (IQ/UNESP), Araraquara, SP (Brazil). Inst. de Quimica. Dept. de Bioquimica e Tecnologia Quimica; Jubilut, Guita Nicolaewsky; Nakaie, Clovis Ryuichi [Universidade Federal de Sao Paulo (UNIFESP), SP (Brazil). Dept. de Biofisica


    Despite the increase in peptide chain aggregation, which decreases the rate of coupling reactions, the synthesis and use of very highly substituted resins still remains as a controversial point in the SPPS, due to its clear economical advantages (lesser solvent consumption and higher amount of peptide per synthesis). In order to better investigate the synthesis and the use of very highly substituted resins, the FTIR, NMR and EPR were compared. By FTIR techniques it was possible to follow all the steps of resin synthesis and the factors affecting the aggregation of the chains inside the peptidil-BHAR and MBHAR. (author)

  19. [Radiopacity of composite resins].

    Tamburús, J R


    The author studied the radiopacity of six composite resins, submitted to radiographic examination in standardized conditions, only with kilovoltage variations. Along with resins it was radiographed an aluminium penetrometer, to compare their optical densities. The results showed that kilovoltagem variations interfered in optical densities of the resins, being more pronounced in 50-55, 55-60 and 60-65 kilovoltages. Despite this, the relations of optical densities as compared with that of penetrometer steps kept unaltered most fo the kilovoltages used.

  20. Biocompatibility of composite resins

    Sayed Mostafa Mousavinasab


    Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concern...

  1. Highly dispersed metal catalyst

    Xiao, Xin; West, William L.; Rhodes, William D.


    A supported catalyst having an atomic level single atom structure is provided such that substantially all the catalyst is available for catalytic function. A process of forming a single atom catalyst unto a porous catalyst support is also provided.


    another ’million-modulus’ epoxy resin. Cast resin properties from a series of epoxy resins hardened with several aromatic diamines are reported, but these data are sufficient to advance only speculative conclusions. (Author)

  3. Catalyst Architecture

    Kiib, Hans; Marling, Gitte; Hansen, Peter Mandal


    How can architecture promote the enriching experiences of the tolerant, the democratic, and the learning city - a city worth living in, worth supporting and worth investing in? Catalyst Architecture comprises architectural projects, which, by virtue of their location, context and their combination...... of programs, have a role in mediating positive social and/or cultural development. In this sense, we talk about architecture as a catalyst for: sustainable adaptation of the city’s infrastructure appropriate renovation of dilapidated urban districts strengthening of social cohesiveness in the city development...

  4. Environmentally friendly one-pot synthesis of alpha-alkylated nitriles using hydrotalcite-supported metal species as multifunctional solid catalysts.

    Motokura, Ken; Fujita, Noriaki; Mori, Kohsuke; Mizugaki, Tomoo; Ebitani, Kohki; Jitsukawa, Koichiro; Kaneda, Kiyotomi


    A ruthenium-grafted hydrotalcite (Ru/HT) and hydrotalcite-supported palladium nanoparticles (Pd(nano)/HT) are easily prepared by treating basic layered double hydroxide, hydrotalcite (HT, Mg(6)Al(2)(OH)(16)CO(3)) with aqueous RuCl(3)n H(2)O and K(2)[PdCl(4)] solutions, respectively, using surface impregnation methods. Analysis by means of X-ray diffraction, and energy-dispersive X-ray, electron paramagnetic resonance, and X-ray absorption fine structure spectroscopies proves that a monomeric Ru(IV) species is grafted onto the surface of the HT. Meanwhile, after reduction of a surface-isolated Pd(II) species, highly dispersed Pd nanoclusters with a mean diameter of about 70 A is observed on the Pd(nano)/HT surface by transmission electron microscopy analysis. These hydrotalcite-supported metal catalysts can effectively promote alpha-alkylation reactions of various nitriles with primary alcohols or carbonyl compounds through tandem reactions consisting of metal-catalyzed oxidation and reduction, and an aldol reaction promoted by the base sites of the HT. In these catalytic alpha-alkylations, homogeneous bases are unnecessary and the only by-product is water. Additionally, these catalyst systems are applicable to one-pot syntheses of glutaronitrile derivatives.

  5. Investigations of toughening mechanisms of epoxy resins

    Koenig, T.


    Composite material technology was applied to the solid rocket booster by the development of a carbon filament-epoxy resin case which yields a net increase of 4000 lbs. in payload in the shuttle. The question of reusability of the new composite tanks has not yet been answered and will depend on the toughness of the matrix resin. The present study was aimed at providing conditions whereby test specimens of the epoxy resin (EPON/85) and curing agents of systematically varied structures could be produced in a controlled manner. Three sets of conditions were found that might allow the isolation of the structural effects on toughness from the cure effects. The kinetic methods leading to the determination of these conditions are described.

  6. 固体酸催化合成水杨酸甲酯进展%Progress of Catalytic Synthesis for Methyl Salicylate with Solid Acid

    刘美艳; 俞善信


    Solid acid is a good catalyst that can be used as catalyst for the esterification instead of sulphuric acid. The synthesis of methyl salicylate catalyzed by p-toluene sulfonic acid, amino sulfonic acid,strongly acidic cationic exchanged resin,cupric bromide, sodium bisulfate monohydrate, solid super acid,heteropoly acid and molecular sieve etc. were reviewed.%固体酸是一种优良的催化剂,能够替代硫酸作为酯化催化剂.评述了对甲苯磺酸、氨基磺酸、强酸性阳离子交换树脂、溴化铜、一水硫酸氢钠、固体超强酸、杂多酸和分子筛等催化合成水杨酸甲酯的方法.

  7. Method for reactivating catalysts and a method for recycling supercritical fluids used to reactivate the catalysts

    Ginosar, Daniel M.; Thompson, David N.; Anderson, Raymond P.


    A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

  8. Heterogeneous Catalysts

    Dakka, J.; Sheldon, R.A.; Sanderson, W.A.


    Abstract of GB 2309655 (A) Heterogeneous catalysts comprising one or more metal compounds selected from the group consisting of tin, molybdenum, tungsten, zirconium and selenium compounds deposited on the surface of a silicalite are provided. Preferably Sn(IV) and/or Mo(VI) are employed. The cat

  9. Preparation of a Sulfonated Carbonaceous Material from Lignosulfonate and Its Usefulness as an Esterification Catalyst

    Duckhee Lee


    Full Text Available Sulfonated carbonaceous material useful as a solid acid catalyst was prepared from lignosulfonate, a waste of the paper-making industry sulfite pulping process, and characterized by 13C-NMR, FT-IR, TGA, SEM and elemental analysis, etc. The sulfonic acid group density and total density of all acid groups in the sulfonated carbonaceous material was determined by titration to be 1.24 mmol/g and 5.90 mmol/g, respectively. Its catalytic activity in the esterification of cyclohexanecarboxylic acid with anhydrous ethanol was shown to be comparable to that of the ionic exchange resin Amberlyst-15, when they were used in the same amount. In the meantime, the sulfonic acid group was found to be leached out by 26%–29% after it was exposed to hot water (95 °C for 5 h. The catalytic usefulness of the prepared carbonaceous material was investigated by performing esterifications.

  10. Interacting Blends of Novel Unsaturated Polyester Amide Resin with Vinyl Acetate

    H. S. Patel


    Full Text Available Novel unsaturated poly (ester- amide resins (UPEAs were prepared by the reaction between an epoxy resin, namely diglycidyl ether of bisphenol–A (DGEBA and unsaturated aliphatic bisamic acids using a base catalyst. These UPEAs were then blended with a vinyl monomer namely, Vinyl acetate (VA to produce a homogeneous resin syrup. The curing of these UPEAs-VA resin blends was carried out by using benzoyl peroxide (BPO as an initiator for the radical polymerization and was monitored by using a differential scanning calorimeter (DSC. The glass fibre reinforced composites (i.e. laminates of these UPEA-VA resin blends were fabricated using the DSC data. The chemical, mechanical and electrical properties of the glass fibre composites have also been evaluated. The unreinforced cured samples of the UPEA-VA resin blends were also analyzed by thermogravimetry (TGA.

  11. Enhanced Heavy Oil Recovery in Mild Conditions by SO42-/TiO2-ZrO2 Solid Superacid Prepared by Different Methods

    Chen Li


    Full Text Available The important key of heavy oil efficient exploring is to decrease the viscosity and increase the flowability. Solid acid catalyst is one of the commonly used catalysts to reducing the viscosity of heavy oil, but good dispersion in oil phase and better catalytic activity are difficult to achieve. Herein, ZrO2-TiO2 was selected as the fundamental catalyst because of its superior solid superacid properties, and CTAB was selected as the surfactant package coat to help enhance catalytic activity. The as-prepared catalysts were characterized systematically by TEM, XRD, FTIR, and N2 adsorption-desorption isotherms measurement. The reduction efficiency of the heavy oil viscosity achieved as high as 66.3% at 180°C. At the same time, the portion of asphaltenes and resins slipped down by 4.93% and 3.78%, respectively, while saturated and aromatic hydrocarbon component increased by 5.37% and 3.26%, respectively, indicating that our catalyst showed a good activity for reducing the viscosity and improving the quality of heavy crude oil.


    Kyser, E.


    The flowsheet for the digestion of Reillex{trademark} HPQ was validated both under the traditional alkaline conditions and under strongly acidic conditions. Due to difficulty in performing a pH adjustment in the large tank where this flowsheet must be performed, the recommended digestion conditions were changed from pH 8-10 to 8 M HNO{sub 3}. Thus, no pH adjustment of the solution is required prior to performing the permanganate addition and digestion and the need to sample the digestion tank to confirm appropriate pH range for digestion may be avoided. Neutralization of the acidic digestion solution will be performed after completion of the resin digestion cycle. The amount of permanganate required for this type of resin (Reillex{trademark} HPQ) was increased from 1 kg/L resin to 4 kg/L resin to reduce the amount of residual resin solids to a minimal amount (<5%). The length of digestion time at 70 C remains unchanged at 15 hours. These parameters are not optimized but are expected to be adequate for the conditions. The flowsheet generates a significant amount of fine manganese dioxide (MnO{sub 2}) solids (1.71 kg/L resin) and involves the generation of a significant liquid volume due to the low solubility of permanganate. However, since only two batches of resin (40 L each) are expected to be digested, the total waste generated is limited.


    XUMancai; OUZhize; 等


    Possibilities for enhancement of catalytic reaction rate by combining phase transfer catalysis and hydrogen bonding of the catalyst with the substrate and reagent were studied.A phase transfer catalyst library with sixty polystyrene-supported quaternary ammonium salt catalysts was synthesized.The reduction of acetophenone by NaBH4 was used as the probing reaction to select out the ost active catalyst in the library by using iterative method.which was the gel-type triethanolamine aminsating strongly asic anion exchange resin with the crosslinking degeree of 2% A hydrogen bonding assisted catalytic mechanism was proposed to explain the high catalytic activity of the catalyst.

  14. Synthesis and Characterization of Modified Epoxy Resins by Silicic Acid Tetraethyl Ester and Nano-SiO2

    李海燕; 张之圣


    A kind of modified epoxy resins was obtained by condensation of epoxy resin with silicic acid tetraethyl ester(TEOS) and nano-SiO2. The reactions were performed with hydrochloric acid as a catalyst at 63 °C.The structure, thermal stability and morphological characteristics of the modified epoxy resins were studied through infrared spectra(FT-IR) analysis, thermogravimetric (TG) analysis and scanning electron microscopy respectively. It has been found from the IR and TG study that modified epoxy resins have greater thermal stability than epoxy resins, and its thermal stability has been improved by the formation of inter-crosslinked network structure. The modified epoxy resins exhibit heterogeneous morphology and heterogeneity increases with more TEOS feeding, which in turn confirms the formation of inter-crosslinked network structure in modified epoxy resins.

  15. Heterogeneous Baylis-Hillman using a polystyrene-bound 4-(N-benzyl-N-methylamino)pyridine as reusable catalyst.

    Corma, Avelino; García, Hermenegildo; Leyva, Antonio


    An insoluble Merrifield type resin having 4-aminopyridine units is a suitable and reusable heterogeneous catalyst for the Baylis-Hillman coupling of aromatic aldehydes and alpha,beta-unsaturated ketones.

  16. A multisite molecular mechanism for Baeyer-Villiger oxidations on solid catalysts using environmentally friendly H2O2 as oxidant.

    Boronat, Mercedes; Corma, Avelino; Renz, Michael; Sastre, Germán; Viruela, Pedro M


    The molecular mechanism of the Baeyer-Villiger oxidation of cyclohexanone with hydrogen peroxide catalyzed by the Sn-beta zeolite has been investigated by combining molecular mechanics, quantum-chemical calculations, spectroscopic, and kinetic techniques. A theoretical study of the location of Sn in zeolite beta was performed by using atomistic force-field techniques to simulate the local environment of the active site. An interatomic potential for Sn/Si zeolites, which allows the simulation of zeolites containing Sn in a tetrahedral environment, has been developed by fitting it to the experimental properties of quartz and SnO2(rutile). The tin active site has been modeled by means of a Sn(OSiH3)3OH cluster, which includes a defect in the framework that provides the flexibility necessary for the interaction between the adsorbates and the Lewis acid center. Two possible reaction pathways have been considered in the computational study, one of them involving the activation of the cyclohexanone carbonyl group by Sn (1) and the other one involving hydrogen peroxide being activated through the formation of a tin-hydroperoxo intermediate (2). Both the quantum-chemical results and the kinetic study indicate that the reaction follows mechanism 1, and that the catalyst active site consists of two centers: the Lewis acid Sn atom to which cyclohexanone has to coordinate, and the oxygen atom of the Sn-OH group that interacts with H2O2 forming a hydrogen bond.

  17. Preparation of FexCe1-xOy solid solution and its application in Pd-only three-way catalysts

    Jianqiang Wang; Meiqing Shen; Jun Wang; Mingshan Cui; Jidong Gao; Jie Ma; Shuangxi Liu


    FeOx-CeO2 mixed oxides with increasing Fe/(Ce+Fe) atomic ratio (1-20 mol%) were prepared by sol-gel method and characterized by X-ray powder diffraction (XRD),Brunauer-Emmett-Teller (BET) and Hydrogen temperature-programmed reduction (H2-TPR) techniques.The dynamic oxygen storage capacity (DOSC) was investigated by mass spectrometry with CO/O2 transient pulses.The powder XRD data following Rietveld refinement revealed that the solubility limit of iron oxides in the CeO2 was 5 mol% based on Fe/(Ce+Fe).The lattice parameters experienced a decrease followed by an increase due to the influence of the maximum solubility limit of iron oxides in the CeO2.TPR analysis revealed that Fe introduction into ceria strongly modified the textual and structural properties,which influenced the oxygen handling properties.DOSC results revealed that Ce-based materials containing Fe oxides with multiple valences contribute to the majority of DOSC.The kinetic analysis indicated that the calculated apparent kinetic parameters obey the compensation effect.The three-way catalytic performance for Pd-only catalysts based on the Fe doping support exhibited the redundant iron species separated out of the CeO2 and interacted with the ceria and Pd species on the surface,which seriously influenced the catalytic properties,especially after hydrothermal aging treatment.

  18. Determination of Human-Health Pharmaceuticals in Filtered Water by Chemically Modified Styrene-Divinylbenzene Resin-Based Solid-Phase Extraction and High-Performance Liquid Chromatography/Mass Spectrometry

    Furlong, Edward T.; Werner, Stephen L.; Anderson, Bruce D.; Cahill, Jeffery D.


    In 1999, the Methods Research and Development Program of the U.S. Geological Survey National Water Quality Laboratory began the process of developing a method designed to identify and quantify human-health pharmaceuticals in four filtered water-sample types: reagent water, ground water, surface water minimally affected by human contributions, and surface water that contains a substantial fraction of treated wastewater. Compounds derived from human pharmaceutical and personal-care product use, which enter the environment through wastewater discharge, are a newly emerging area of concern; this method was intended to fulfill the need for a highly sensitive and highly selective means to identify and quantify 14 commonly used human pharmaceuticals in filtered-water samples. The concentrations of 12 pharmaceuticals are reported without qualification; the concentrations of two pharmaceuticals are reported as estimates because long-term reagent-spike sample recoveries fall below acceptance criteria for reporting concentrations without qualification. The method uses a chemically modified styrene-divinylbenzene resin-based solid-phase extraction (SPE) cartridge for analyte isolation and concentration. For analyte detection and quantitation, an instrumental method was developed that used a high-performance liquid chromatography/mass spectrometry (HPLC/MS) system to separate the pharmaceuticals of interest from each other and coextracted material. Immediately following separation, the pharmaceuticals are ionized by electrospray ionization operated in the positive mode, and the positive ions produced are detected, identified, and quantified using a quadrupole mass spectrometer. In this method, 1-liter water samples are first filtered, either in the field or in the laboratory, using a 0.7-micrometer (um) nominal pore size glass-fiber filter to remove suspended solids. The filtered samples then are passed through cleaned and conditioned SPE cartridges at a rate of about 15

  19. Synthesis of carbon nanotubes via Fe-catalyzed pyrolysis of phenolic resin

    Wang, Junkai; Deng, Xiangong; Zhang, Haijun; Zhang, Yuanzhuo; Duan, Hongjuan; Lu, Lilin; Song, Jianbo; Tian, Liang; Song, Shupeng; Zhang, Shaowei


    Carbon nanotubes (CNTs) with 40-100 nm in diameter and tens of micrometers in length were prepared via catalytic pyrolysis of phenol resin in Ar at 673-1273 K using ferric nitrate as a catalyst precursor. Structure and morphology of pyrolyzed resin were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy. Ferric nitrate was transformed to Fe3O4 at 673 K, and to metallic Fe and FexC carbide at 873-1273 K. The optimal weight ratio of Fe catalyst to phenol resin for growing CNTs was 1.00 wt%, and the optimal temperature was 1073 K. In addition, use of a high pressure increased the yield of CNTs. Density functional theory (DFT) calculations suggest that Fe catalysts facilitate the CNTs growth by increasing the bond length and weakening the bond strength in C2H4 via donating electrons to the C atoms in it.

  20. Biocidal quaternary ammonium resin

    Janauer, G. E.


    Activated carbon (charcoal) and polymeric resin sorbents are widely used in the filtration and treatment of drinking water, mainly to remove dissolved organic and inorganic impurities and to improve the taste. Earlier hopes that activated carbon might "disinfect' water proved to be unfounded. The feasibility of protecting against microbial infestation in charcoal and resin beds such as those to be incorporated into total water reuse systems in spacecraft was investigated. The biocidal effect of IPCD (insoluable polymeric contact disinfectants) in combination with a representative charcoal was assessed. The ion exchange resins (IPCD) were shown to adequately protect charcoal and ion exchange beds.

  1. Biocompatibility of composite resins

    Sayed Mostafa Mousavinasab


    Full Text Available Dental materials that are used in dentistry should be harmless to oral tissues, so they should not contain any leachable toxic and diffusible substances that can cause some side effects. Reports about probable biologic hazards, in relation to dental resins, have increased interest to this topic in dentists. The present paper reviews the articles published about biocompatibility of resin-restorative materials specially resin composites and monomers which are mainly based on Bis-GMA and concerns about their degradation and substances which may be segregated into oral cavity.

  2. Study on catalyst for the sodium borohydride hydrolysis

    WANG; Shu-ming; JIANG; Li-jun; LIU; Xiao-peng; WANG; Shu-mao


    The effects of preparation methods, supports and active parts on both the activation and stability of catalyst for the sodium borohydride hydrolysis were studied, and the results showed that the activation and stability of the catalysts prepared by impregnation method is better than that prepared by chemical plating. Compared to exchange resin and activated alumina, the diatomite with high BET surface area and porosity is more suitable for as the catalyst's support. Co is much better than Ni when used as catalytic active part.

  3. Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments

    Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan


    Objective: The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. Materials and Methods: A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the res...

  4. Synthesis, Characterization and Thermal Analysis of Resins from Different Cardanol Based Dyes

    Tapan K. Das


    Full Text Available Cardanol(Cashew phenol is subjected to diazotisation with Aniline and m-Toluidine to get monomers like Cardanol based dye from Aniline (CBDFA and Cardanol based dye from m-Toludine (CBDFT. Such monomers have been condensed with formaldehyde in presence of acid catalyst to form resins. The resins have been characterized by FTIR spectra and their thermal behaviour have been studied.

  5. Determination of the gel point of a polyfurfuryl alcohol resin and characterization of its curing rheokinetics

    Dominguez, Juan Carlos; Madsen, Bo


    The determination of the gel point of a resin is a key in order to design and optimize the manufacturing process of composite materials. In this work, the gel point of a biobased polyfurfuryl alcohol (FA) resin has been determined by rheological isothermal tests at different curing temperatures. The obtained gel times using three different amounts of catalyst (2, 4 and 6 % wt.) were correlated to temperature by the Macosko model; to predict the gel time at any temperature within the studied r...

  6. Synthesis and characterization of MCM-41-supported nano zirconia catalysts

    Mohamed S. Abdel Salam


    Full Text Available Series of MCM-41 supported sulfated Zirconia (SZ catalysts with different loadings (2.5–7.5% wt. were prepared using direct impregnation method. The acquired solid catalysts were characterized structurally and chemically using X-RD, HRTEM, BET, FT-IR, Raman spectroscopy and TPD analysis. The acidity of the solid catalysts was investigated through cumene cracking and isopropanol dehydration at different temperatures. As the SZ loading increases, the surface acidity of the mesoporous catalysts was enhanced, this was reflected by the higher catalytic activity toward cumene cracking and isopropanol dehydration.

  7. Self-encoding Functional Resin Applying for Combinatorial Chemistry and High Throughput Screening

    DU Lei; CHEN Tong-sheng


    A novel solid phase organic synthesis resin was synthesized for combinatorial high-throughput screening,which based on FTIR spectra self-encoding functional resin technology. A new deconvolution strategy termed position encoding deconvolution had illustrated and was compared with some popular combinatorial deconvolution strategies in efficiency and information content. The mimic high throughput screening of hexapeptide library successfully proved the applying of the self-encoding functional resin technology and the position encoding deconvolution strategy.

  8. Chemical Stablilisation of Sand : Part VIII Furan Resins as Dune and Coastal Sand Stabiliser

    Ram Gopal


    Full Text Available Studies on furan resin as dune sand stabiliser are presented. Influence of acid catalysts, viz. phenol disulphonic acid, sulphuric acid, hydrochloric acid and phosphoric acid and other catalysts, viz. trichlorotoluene and benzoyl chloride along with promoters, zinc chloride and ferric chloride, on the strength of stabilised furan resin-sand specimens has been discussed. Optimisation studies on resin content, catalysts and promoters and curing conditions have revealed that maximum strength of 260 kg/cm/sup 2/ of the standard specimens made by compaction of coastal sand using furan resins (10 per cent, sulphuric acid (9N, 30 per cent and a curing time of 2 hr at 40 degree Centigrade is higher than the 170 kg/cm/sup 2/ of specimens made of Rajasthan desert sand. Sandy patches stabilised by seepage technique recorded a maximum strength of 125 kg/cm/sup 2/. Physico-chemical characteristics of this system and effect of environment on stabilised specimens have also been studied and field trials conducted successfully. This resin-catalyst system would be extremely useful in humid and saline field (coastal areas for different military applications.

  9. Catalyst Architecture

    Kiib, Hans; Marling, Gitte; Hansen, Peter Mandal


    of programs, have a role in mediating positive social and/or cultural development. In this sense, we talk about architecture as a catalyst for: sustainable adaptation of the city’s infrastructure appropriate renovation of dilapidated urban districts strengthening of social cohesiveness in the city development...... meaningful for everyone. The exhibited works are designed by SANAA, Diller Scofidio + Renfro, James Corner Field Operation, JBMC Arquitetura e Urbanismo, Atelier Bow-Wow, Ateliers Jean Nouvel, COBE, Transform, BIG, Topotek1, Superflex, and by visual artist Jane Maria Petersen....

  10. Process for encapsulating toxic or radioactive wastes into thermosetting resins. Procede de conditionnement de dechets radioactifs ou toxiques dans des resines thermodurcissables

    Barlou, A.; Beltritti, A.; Gramondi, P.; Vidal, H.


    A liquid hardener non miscible with water and with a density higher than water density is mixed to wastes stored in water. After decantation water is removed and the wastes with the hardening agent are mixed with the epoxy resin to obtain a solid block. In particular wastes can be ion exchange resins. Addition of hardener to wastes in water limits temperature increase during hardening and improves density of solid products.

  11. Nanostructured Basic Catalysts: Opportunities for Renewable Fuels

    Conner, William C; Huber, George; Auerbach, Scott


    This research studied and developed novel basic catalysts for production of renewable chemicals and fuels from biomass. We focused on the development of unique porous structural-base catalysts zeolites. These catalysts were compared to conventional solid base materials for aldol condensation, that were being commercialized for production of fuels from biomass and would be pivotal in future biomass conversion to fuels and chemicals. Specifically, we had studied the aldolpyrolysis over zeolites and the trans-esterification of vegetable oil with methanol over mixed oxide catalysts. Our research has indicated that the base strength of framework nitrogen in nitrogen substituted zeolites (NH-zeolites) is nearly twice as strong as in standard zeolites. Nitrogen substituted catalysts have been synthesized from several zeolites (including FAU, MFI, BEA, and LTL) using NH3 treatment.

  12. Dimerisation of isobutene on acidic ion-exchange resins

    Honkela, Maija


    Dimerisation of isobutene produces diisobutenes that can be hydrogenated to isooctane (2,2,4-trimethyl pentane). Isooctane can be used as a high octane gasoline component. The aim of this work was to study the selective production of diisobutenes through the dimerisation of isobutene on ion-exchange resin catalysts and to construct kinetic models for the reactions in the system for reactor design purposes. High selectivities for diisobutenes were obtained in the presence of polar componen...


    班卫平; 高世萍; 宋文静; 朱宏伟; 崔贺


    采用负载型有机高分子固体酸和液体质子酸混合催化水合萜二醇脱水合成松油醇,总产率99%,松油醇选择性83%,产率74%以上,考察了催化剂用量、反应时间、醇水比等对松油醇产率的影响,确定了最佳工艺条件,为松油醇的工业生产提供条件。%Organic solid acid, together with liquid acid, was used ascatalyst for preparing terpineol from terpene hydrate at total yield 99%, selectivity of terpineol 83%, terpineol yield 74%. Effects of catalyst amount, reaction time, ratio of terpene hydrate to water on the yield of terpineol were examined. Optimal conditions for synthesizing terpineol were obtained.

  14. Catalysts derived from waste slag for transesterification

    Xiaowei Zhang; Wei Huang


    MgO-CaO/SiO2 solid catalysts derived from waste slag (WS) of metal magnesium plant were prepared.The catalytic performances were evaluated in the transesterification of rapeseed oil with methanol to biodiesel in a 500 mL three-necked reactor under atmospheric pressure.The basic strengh of the catalyst reached 22.0 measured by indicators accroding to Hammett scale.The results show that the MgO-CaO/SiO2 is an excellent catalyst for transesterification, and the conversion of rapeseed oil reach 98% under the optimum condition.

  15. Imide modified epoxy matrix resins

    Scola, D. A.


    The results of a program designed to develop tough imide modified epoxy resins cured by bisimide amine (BIA) hardeners are described. State-of-the-art epoxides MY720 and DER383 were used, and four bismide amines were evaluated. These were the BIA's derived from the 6F anhydride (4,4'-(hexafluoroisopropylidene) bis(phthalic anhydride) and the diamines 3,3'-diaminodiphynyl sulfone, 4,4'-oxygianiline, 4,4'-methylene dianiline, and 1,12-dodecane diamine. A key intermediate, designated 6F anhydride, is required for the synthesis of the bisimide amines. Reaction parameters to synthesize a precursor to the 6F anhydride (6FHC) in high yields were investigated. The catalyst trifluoromethane sulfonic acid was studied. Although small scale runs yielded the 6FHC in 50 percent yield, efforts to ranslate these results to a larger scale synthesis gave the 6FHC in only 9 percent yield. Results show that the concept of using bisimide amine as curing agents to improve the toughness properties of epoxies is valid.

  16. Application conditions for ester cured alkaline phenolic resin sand

    Ren-he Huang; Bao-ping Zhang; Yao-ji Tang


    Five organic esters with different curing speeds: propylene carbonate (i.e. high-speed ester A); 1, 4-butyrolactone; glycerol triacetate (i.e. medium-speed ester B); glycerol diacetate; dibasic ester (DBE) (i.e. low-speed ester C), were chosen to react with alkaline phenolic resin to analyze the application conditions of ester cured alkaline phenolic resin. The relationships between the curing performances of the resin (including pH value, gel pH value, gel time of resin solution, heat release rate of the curing reaction and tensile strength of the resin sand) and the amount of added organic ester and curing temperature were investigated. The results indicated the folowing: (1) The optimal added amount of organic ester should be 25wt.%-30wt.% of alkaline phenolic resin and it must be above 20wt.%-50 wt.% of the organic ester hydrolysis amount. (2) High-speed ester A (propylene carbonate) has a higher curing speed than 1, 4-butyrolactone, and they were both used as high-speed esters. Glycerol diacetate is not a high-speed ester in alkaline phenolic resin although it was used as a high-speed ester in ester cured sodium silicate sand; glycerol diacetate and glycerol triacetate can be used as medium-speed esters in alkaline phenolic resin. (3) High-speed ester A, medium-speed ester B (glycerol triacetate) and low-speed ester C (dibasic ester, i.e., DBE) should be used below 15 ºC, 35 ºC and 50 ºC, respectively. High-speed ester A or low-speed ester C should not be used alone but mixed with medium-speed ester B to improve the strength of the resin sand. (4) There should be a suitable solid content (generaly 45wt.%-65wt.% of resin), alkali content (generaly 10wt.%-15wt.% of resin) and viscosity of alkaline phenolic resin (generaly 50-300 mPa·s) in the preparation of alkaline phenolic resin. Finaly, the technique conditions of alkaline phenolic resin preparation and the application principles of organic ester were discussed.

  17. High energy electron beam curing of epoxy resin systems incorporating cationic photoinitiators

    Janke, Christopher J.; Lopata, Vincent J.; Havens, Stephen J.; Dorsey, George F.; Moulton, Richard J.


    A mixture of epoxy resins such as a semi-solid triglycidyl ether of tris (hydroxyphenyl) methane and a low viscosity bisphenol A glycidyl ether and a cationic photoinitiator such as a diaryliodonium salt is cured by irradiating with a dosage of electron beams from about 50 to about 150 kGy, forming a cross-linked epoxy resin polymer.

  18. Heterogeneous Catalyst Deactivation and Regeneration: A Review

    Morris D. Argyle


    Full Text Available Deactivation of heterogeneous catalysts is a ubiquitous problem that causes loss of catalytic rate with time. This review on deactivation and regeneration of heterogeneous catalysts classifies deactivation by type (chemical, thermal, and mechanical and by mechanism (poisoning, fouling, thermal degradation, vapor formation, vapor-solid and solid-solid reactions, and attrition/crushing. The key features and considerations for each of these deactivation types is reviewed in detail with reference to the latest literature reports in these areas. Two case studies on the deactivation mechanisms of catalysts used for cobalt Fischer-Tropsch and selective catalytic reduction are considered to provide additional depth in the topics of sintering, coking, poisoning, and fouling. Regeneration considerations and options are also briefly discussed for each deactivation mechanism.

  19. Furfural resin-based bio-nanocomposites reinforced by reactive nanocrystalline cellulose

    Wang, C.; Sun, S.; Zhao, G.; He, B.; Xiao, H.


    The work presented herein has been focused on reinforcing the furfural resins (FA) by reactive-modified nanocrystalline cellulose (NCC) in an attempt to create a bio-nanocomposite completely based on natural resources. FA prepolymers were synthesized with an acid catalyst, and NCC was rendered reactive via the grafting of maleic anhydride (MAH). The resulting NCC and nanocomposites were characterized using TEM, SEM and FT-IR. It was found that NCC appeared to be spherical in shape with diameters under 100 nm. FT-IR confirmed that there were hydrogen and esterification bonding between MAH and NCC or FA prepolymer. After solidified with paratoluenesulfonic acid, NCC-reinforced FA resin composites showed granular cross-section while FA resin with layered structures. Mechanical property tests indicated that NCC-reinforced FA resin composites possessed the improved tensile and flexural strengths, in comparison with FA resin.

  20. Electrodeposition of a Au-Dy2O3 Composite Solid Oxide Fuel Cell Catalyst from Eutectic Urea/Choline Chloride Ionic Liquid

    Claudio Mele


    Full Text Available  In this research we have fabricated and tested Au/Dy2O3 composites for applications as Solid Oxide Fuel Cell (SOFC electrocatalysts. The material was obtained by a process involving electrodeposition of a Au-Dy alloy from a urea/choline chloride ionic liquid electrolyte, followed by selective oxidation of Dy to Dy2O3 in air at high temperature. The electrochemical kinetics of the electrodeposition bath were studied by cyclic voltammetry, whence optimal electrodeposition conditions were identified. The heat-treated material was characterised from the morphological (scanning electron microscopy, compositional (X-ray fluorescence spectroscopy and structural (X-ray diffractometry points of view. The electrocatalytic activity towards H2 oxidation and O2 reduction was tested at 650 °C by electrochemical impedance spectrometry. Our composite electrodes exhibit an anodic activity that compares favourably with the only literature result available at the time of this writing for Dy2O3 and an even better cathodic performance.

  1. Disintegration and dissolution of spent radioactive cationic exchange resins using Fenton-like oxidation process

    Wan, Zhong; Xu, Lejin [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Wang, Jianlong, E-mail: [Collaborative Innovation Center for Advanced Nuclear Energy Technology, INET, Tsinghua University, Beijing 100084 (China); Beijing Key Laboratory of Radioactive Wastes Treatment, Tsinghua University, Beijing 100084 (China)


    Highlights: • The spent radioactive resins could be oxidized by Fenton-like process. • The influencing factors on resin oxidation were evaluated. • Chemical oxygen demand (COD) reduction rate was more than 99%. • SEM and Raman spectrum were used to analyze the resins morphological change. - Abstract: The treatment and disposal of the spent radioactive resins is essential for the sustainable development of the nuclear industry. In this paper, the disintegration and dissolution of spent cationic resins were studied by Fenton-like process. The influencing factors on resin dissolution, such as pH, temperature, type and concentration of catalysts were evaluated. The results showed that the spent resins could be effectively dissolved at pH < 1, [Fe{sup 2+}] = 0.2 M and T = 97 ± 2 °C. Chemical oxygen demand (COD) reduction rate was more than 99%. The scanning electron microscopy and the Raman spectrum were used to observe the morphological changes of the spent resins during the dissolution process. Fenton-like oxidation is an efficient method for the volume reduction and stabilization of the spent resins before further immobilization.

  2. Study on selective alkylation of camphene with O-Cresol over solid acid catalyst%固体酸催化莰烯与邻甲酚的选择性烷基化反应

    周调调; 刘六军; 白杨; 宋先亮


    详细考察了各类固体酸催化剂对莰烯与邻甲酚烷基化产物选择性的影响.采用气相色谱、气相色谱-质谱联用技术、核磁和红外表征了烷基化产物,并对结果进行了分析.实验结果表明:以丝光沸石为催化剂,用量为6%,莰烯与邻甲酚的物质的量的比为1∶1.5,反应温度为160℃,莰烯的转化率为99.89%,目标C-C烷基化产物的选择性可达77.48%.以脱铝丝光沸石,Al -HM为催化剂,莰烯的转化率分别达到99.36%、99.6%,目标C-C烷基化产物的选择性分别为77.57%和80.5%.%The selectivity of alkylation product of camphene with o-cresol over various types of solid acid catalysts were studied in detail. The alkylation products were identified by GC, GC-MS, IR, 'H-NMR, and the results were analyzed. The results show that when 6% of H-Mordenite is used, reacting at 160℃ with o-cresol and camphene molar ratio of 1. 5:1 ,the conversion of camphene is 99. 89% ,and the selectivity of the desired C-C alkylation product is up to 77. 48% ;When dealuminated HM and Al-HM are taken as catalysts respectively, the conversion rates of camphene are 99.36% and 99.6% respectively, and the selectivity of the desired C-C alkylation product are up to 77.57% and 80. 5% separately.

  3. Research progress in H2O2/solid catalyst carrier for oxidative desulfurization%H2O2/固体催化剂氧化脱硫体系中载体的研究进展

    王广建; 崔会杰; 冯庆吉; 韩亚飞; 王芳


    从研究应用角度出发,综述了近年来 H2O2/固体催化剂氧化脱硫体系中载体的研究进展和发展趋势,分别从单一氧化物载体、复合氧化物载体、活性炭载体、分子筛及复合分子筛载体4个方面论述了氧化脱硫催化剂载体各自的优缺点及应用成果。单一氧化物载体重点介绍了 Al2O3、TiO2、SiO2、ZrO2;复合氧化物载体主要对二元复合氧化物进行了综述;重点介绍了以 ZSM-5、SBA-15、MCM-41、HMS 为代表的分子筛及复合分子筛载体。最后将不同类型载体的结构特点、反应优缺点等进行了归纳总结,展望了氧化脱硫催化剂载体未来的研究方向,并提出分子筛及复合分子筛载体将是氧化脱硫催化剂载体研究的焦点。%The article summarizes the research progress and development of carriers in the system of oxidative desulfurization with solid catalyst H2O2. Advantages,disadvantages and application results are discussed from following four aspects:single oxide carrier,mixed oxide carrier,activated carbon carrier,molecular sieve and composite molecular sieve carrier. As single carriers,Al2O3,TiO2,SiO2 and ZrO2 are emphatically introduced; and binary compound oxides are specially introduced in mixed oxide carriers. The molecular sieve and composite molecular sieve carrier represented by ZSM-5, SBA-15,MCM-41 and HMS are also introduced emphatically. Finally,we give an induction and summarization on structural characteristics,advantages and disadvantages in the reaction of different carriers. The research tendency of oxidative desulfurization carrier is prospected,meanwhile,molecular sieve and composite molecular sieve carrier are proposed as the key research focuses of catalyst carriers for oxidative desulfurization in the future.


    LingDaren; LiuYucheng; 等


    The self-diffusion of Eu3+ ion in porous resins D72 and D751 was studied by isotope exchange reaction.Applying Kataoka's bidisperse pore model,the intraparticle effective diffusivity De were resolved into a solid diffusivity Dg and a macropore diffusivity Dp.The experiments show that De.Dp and Dg all increase with the increase of reaction temperature;the response Dp and Dg of D751 resin is smaller than that of D72 resin;the diffusivity of Eu3+ ion in solution is larger than Dp,which leads to the conclusion that the diffusion of ion in the pore of resin can not completely be equal to that in solution.

  5. Stabilization and volume reduction of radioactive spent ionexchange resins


    Stabilization and volume reduction of spent radioactive ion-exchange resins (IERs)were studied. Stabilization technology includes volume reduction with wet chemicaloxidation process and immobilization of the residue into cement. Undersuitable conditions, the exhaustedradioactive ion-exchange resins were dissolved successfully in aH2O2-Fe2+/Cu2+ catalytic oxidationsystem (Fenton reagent). The analytical results indicated that the radioactive nuclides loaded in the resins were concentrated in decomposed solution and solid residues. The process parameters ofwet chemical oxidation and solidification were also obtained. Thedecomposition ratios were 100%and more than 90% for cation and anion IERs respectively. The waste volume was decreased by40% compared with that of original spent resins.

  6. Catalyst Architecture

    the projects as case studies, which contribute with strategic knowledge rather than generalizing from average considerations. These are ‘strategic projects’ where we have looked for the specific and the particular (Flyvbjerg 1991). According to the case studies, we use the case study method developed by Bent......’ interpretations and architectural strategies are included in the analyses. This implies that there is a large variation of empirical knowledge about the selected problems. That is the reason why we give a short introduction to the exact use of approaches and methods in the beginning of each case study. Based...... in experience? Which design qualities do the best examples of architecture as urban catalysts have, and how can we as citizens, politicians and professionals use knowledge about this in the development of our cities as good places to live? We wish to throw light on these key questions through case studies...

  7. 固体单相催化剂CVD法制备成束或分散MWCNT%Solid Single Phase Catalyst for Growth of Bundled or Dispersed MWCNT by CVD

    徐军明; 张孝彬; 李昱; 陶新永; 陈飞; 杨晓芳


    Fe-Mo-Mg-O catalyst prepared by combustion method has great efficiency to grow carbon nanotubes with CVD method. Through investigation of TEM, it is found that bundles of multi-wall carbon nanotubos (MWCNT) can be got when the catalyst is directly used to synthesize the product in CH4/H2 afinosphere; however, the dispersed carbon nanotubes are obtained while the catalyst is reduced firstly in the H2 before the synthesis. The morphology and structure of the catalysts before and after reduced are analyzed by TEM and XRD. The growth mechanism is suggeested for the formation off these two kinds of carbon nanotubes.

  8. Catalyst design for biorefining.

    Wilson, Karen; Lee, Adam F


    The quest for sustainable resources to meet the demands of a rapidly rising global population while mitigating the risks of rising CO2 emissions and associated climate change, represents a grand challenge for humanity. Biomass offers the most readily implemented and low-cost solution for sustainable transportation fuels, and the only non-petroleum route to organic molecules for the manufacture of bulk, fine and speciality chemicals and polymers. To be considered truly sustainable, biomass must be derived from resources which do not compete with agricultural land use for food production, or compromise the environment (e.g. via deforestation). Potential feedstocks include waste lignocellulosic or oil-based materials derived from plant or aquatic sources, with the so-called biorefinery concept offering the co-production of biofuels, platform chemicals and energy; analogous to today's petroleum refineries which deliver both high-volume/low-value (e.g. fuels and commodity chemicals) and low-volume/high-value (e.g. fine/speciality chemicals) products, thereby maximizing biomass valorization. This article addresses the challenges to catalytic biomass processing and highlights recent successes in the rational design of heterogeneous catalysts facilitated by advances in nanotechnology and the synthesis of templated porous materials, as well as the use of tailored catalyst surfaces to generate bifunctional solid acid/base materials or tune hydrophobicity.

  9. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    Chang, Binbin; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng


    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl2 using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl2 at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of -SO3H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N2 adsorption-desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of -SO3H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of -SO3H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and -SO3H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles.

  10. A conveniently prepared Tc-99m resin for semisolid gastric emptying studies

    Wirth, N.; Swanson, D.; Shapiro, B.; Nakajo, M.; Coffey, J.L.; Eckhauser, F.; Owyang, C.


    A polystyrene resin, suitable for semi-solid gastric emptying studies, was rapidly (less than 20 min) and conveniently prepared using commercially available reagents. Using the outlined procedure, Chelex-100 resin bound Tc-99m with greater than 98% labeling efficiency. The resulting Tc-99m Chelex-100 resin demonstrated excellent in vitro and in vivo stability. The clinical application of Tc-99m Chelex-100 resin, mixed with oatmeal, was tested in normal subjects and in various patient groups, including diabetic autonomic neuropathy, pyloric obstruction, postoperative dumping syndrome, and morbidly obese patients before and after gastroplasty.

  11. Conveniently prepared Tc-99m resin for semisolid gastric emptying studies

    Wirth, N. (Univ. of Michigan, Ann Arbor); Shapiro, B.; Nakajo, M.; Coffey, J.L.; Eckhauser, F.; Owyang, C.


    A polystyrene resin, suitable for semi-solid gastric emptying studies, was rapidly (<20 min) and coveniently prepared using commercially available reagents. Using the outlined procedure, Chelex-100 resin bound Tc-99m with greater than 98% labeling efficiency. The resulting Tc-99m Chelex-100 resin demonstrated excellent in vitro and in vivo stability. The clinical application of Tc-99m Chelex-100 resin, mixed with oatmeal, was tested in normal subjects and in various patient groups, including diabetic autonomic neuropathy, pyloric obstruction, postoperative dumping syndrome, and morbidly obese patients before and after gastroplasty.


    King, W; Fernando Fondeur, F; Bill Wilmarth, B; Myra Pettis, M; Shirley Mccollum, S


    Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.

  13. Reactivity of Resorcinol Formaldehyde Resin with Nitric Acid

    King, William D.; Fondeur, Fernando F.; Wilmarth, William R.; Pettis, Myra E.


    Solid-state infrared spectroscopy, differential scanning calorimetry, and elemental analysis have been used to evaluate the reactivity of resorcinol formaldehyde resin with nitric acid and characterize the solid product. Two distinct reactions were identified within the temperature range 25-55 C. The first reaction is primarily associated with resin nitration, while the second involves bulk oxidation and degradation of the polymer network leading to dissolution and off-gassing. The threshold conditions promoting reaction have been identified. Reaction was confirmed with nitric acid concentrations as low as 3 M at 25 C applied temperature and 0.625 M at 66 C. Although a nitrated resin product can be isolated under appropriate experimental conditions, calorimetry testing indicates no significant hazard associated with handling the dry material.


    WU Shihua; ZHU Changying; HUANG Wenqiang


    D-72 resin supported nickel-copper catalysts prepared by solvated metal atom impregnation (SMAI) were studied by magnetic measurements and X-ray photoelectron spectroscopy (XPS). The Ni particles on the catalysts are very highly dispersed and display superparamagnetic behaviour. Ni-Cu alloy clusters were found to be formed. The surface compositions are different from the bulk concentrations. In contrast with the surface enrichment in copper generally observed on conventional Ni-Cu catalysts, the surfaces of these catalysts are enriched in nickel. The nickel is in both zero and valent states, while copper is mainly in metallic state. Catalytic data show that the formation of Ni-Cu alloy clusters has a profound effect on the catalytic activities of the catalysts in the hydrogenation of furfural. The activity of the Ni:Cu ratio of one bimetallic catalysts is much higher than that of the Ni or Cu monometallic catalyst.

  15. Preparation and application of aqueous organosilicon-modified polyester resin%水性有机硅改性聚酯树脂的合成与应用

    张丽丽; 曾敬荣; 江俊鸿; 杨雁; 俞金柱


    In this paper, hydroxy polyester resins were synthesized through melting. In this process, anti-monous oxide was used as catalyst and 10%, 30% and 50% of organosilicon intermediate was used to chemical modification respectively. The modified organosilicon polyester resin with trimellitic anhydride was processed with water base-side processing,then salted with dimethylethanolamine. This kind of water-soluble organosilicon modified polyester resin treated with this way was used to cure and film with amino resin, which performs excellent high temperature resistant, high solidity and excellent flexibility. The experiment results showed that the compositive property and the price performance is the best when the content of organosilicon is 30%.%本文以Sb2O3为催化剂,采用熔融法合成端羟基聚酯树脂,分别以10%、30%、50%的有机硅中间体进行化学改性,以偏苯三甲酸酐对有机硅改性后的聚酯进行了水性化封端,并采用二甲基乙醇胺成盐,制备的水性有机硅改性聚酯树脂配以氨基树脂固化成膜后,表现出具有优良耐高温性、高硬度、良好柔韧性等性能,实验表明,当有机硅含量为30%时,改性聚酯树脂树脂的综合性能和性价比最好.

  16. Estudio de la síntesis de acetato de butilo 1. Selección del Caralizador Study of the butyl acetate synthesis - 1. Catalyst selection

    Carballo Suárez Luis María


    Full Text Available En este trabajo se realizó un estudio de selección, a escala de laboratorio, sobre ocho agentes catalíticos para la reacción de esterificación de ácido acético y butanol (siete resinas de intercambio catiónico y una matriz zeolitíca. Tomando en cuenta algunos parámetros fisicoquímicos, como los pretratamientos requeridos para la activación, la acidez, la resistencia térmica, el desempeño en reacción, etc, se encontró que las resinas de intercambio macroporosas son los catalizadores más eficientes específicamente la resina Lewatit K-2431.In this work, a laboratory scale selection study over eight catalytic agents was made, in the acetic acid and butyl alcohol esterification reaction (seven lon exchange resins and a zeolytic solid. Considering some physicochemical characteristics as the activation pre-treating requirements, acidity, thermal stability, reaction performance, etc., it was found that macroporous ion exchange resins are the most efficient catalysts, especially Lewatit K-2431 resin.

  17. Synthesis, characterization and catalytic performance of supported solid base catalyst of KOH/SBA-15%KOH/SBA-15负载型固体碱催化剂的合成、表征及催化性能

    朱明明; 万庆宇; 宋芊慧; 蔡天凤; 李会鹏; 赵华


    采用后合成法制备出固体碱催化剂KOH/SBA-15,利用X射线衍射法(XRD)、N2吸附-脱附(BET)、透射电镜(TEM)、化学吸附剂表面碱性测定(CO2-TPD)等对其进行表征.考察了其在大豆油酯交换反应制备生物柴油中的催化性能.结果表明,在相同反应条件下,与CaO/SBA-15和MgO/SBA-15相比,KOH/SBA-15在催化活性和孔扩散上都具有较大的优越性,催化制备生物柴油产率最高(83.56%).%SBA-15 was modified by introducing an active component by post-synthetic method for preparing a solid base catalyst KOH/SBA-15. Characterization was carried out by XRD,BET,TEM and CO2-TDP to understand the nature. KOH/SBA-15 catalytic performance on transesterification to produce biodiesel from soybean oil was studied. In the same reaction conditions, compared to CaO/SBA-15 and MgO/SBA-15,(15%)KOH/SBA-15 showed the highest yield of biodiesel,due to its favorable superiority on catalytic activity and pore diffusion.

  18. The influence of urea formaldehyde resins on pyrolysis characteristics and products of wood-based panels

    Yongshun Feng


    Full Text Available In China each year, large amounts of wood-based panels are consumed and abandoned. These are huge resources for energy recovery and materials reuse. In order to study the influence of urea formaldehyde resin (UF resin on waste wood-based panels during pyrolysis, thermobalance experiments together with the evolution of main gaseous products of wood, wood-based panels, and UF resins were carried out and analyzed by TG-FTIR. Elementary and GC-MS analyses were also done to study the characteristics of solid and liquid products. Results from TG and DTG analyses indicated that UF resin used in wood-based panels accelerated the degradation rate of wood-based panels at lower temperature; however the resin inhibited the degradation of wood-based panels over the later stage at higher temperatures. Compared with solid wood, the higher intensity and earlier releasing time of HNCO and NH3 in wood board revealed that the release of nitric gases is mainly due to the presence of UF resin, especially between 180 °C and 320 °C. Mass loss of hydrogen is significantly inhibited by UF resin, and nitrogen is quite stable in the char. The influence of UF resin on pyrolysis liquids of wood-based panels is mainly on nitrogen compounds and ketones rather than aldehydes and esters, which is probably due to the chemical reactions of UF resin with lignin constituent in wood.

  19. Low velocity impact response and damage evolution in unreinforced resin systems and self-repairing polymer matrix composites

    Motuku, Molefi

    The low velocity impact response and damage evolution in unreinforced polymer matrices, conventional polymer matrix composites, and self-repairing polymer matrix composites was investigated. The impact response study of unreinforced matrices and conventional laminates was undertaken because the failure initiation energies, threshold energy levels, failure characteristics and damage evolution in both the matrix material (unreinforced resin plaques) and the composite are intrinsic to proper design of a self-repairing composite. The self-repairing concept was investigated due to its attractive potential to alleviate damage problems in polymer matrix composites. Self-repairing composites, which fall under the category of passive smart polymer composites, have the potential to self repair both micro- and macro-damage resulting from impacts as well as non-impact loading. The self-repairing mechanism is achieved through the incorporation of hollow fibers in addition to the normal solid reinforcing fibers. The hollow fibers store the damage-repairing solution or chemicals that are released into the matrix or damaged zone upon fiber failure to repair and/or arrest damage progression. The room temperature low velocity impact response and damage evolution in DERAKANE 411-350 and 411-C50 vinyl ester unreinforced resin systems was investigated as a function of impact energy level, sample thickness, matrix material and catalyst system. The low velocity impact response of conventional and self-repairing glass reinforced polymer composites was investigated by addressing the fabrication and some of the parameters that influence their response to low velocity impact loading. Specific issues addressed by this study include developing a process to fabricate self-repairing laminates, processing quality; selection of storage material for the repairing solution; release and transportation of repairing solution; the effect of the number, type and spatial distribution of the repairing

  20. Idea of environmental catalyst and its application; Kankyo shokubai no hasso to sono riyo

    Inumaru, K. [The University of Tokyo, Tokyo (Japan)


    The catalyst creating environmental conservation and comfortable environment is generally named an `environmental catalyst (EC).` EC is roughly classified into direct and indirect type ECs. Purification catalysts for automobile exhaust gas, and catalysts for chemical production process are under investigation as direct and indirect type ECs, respectively. The catalyst was found which can remove NOx under the coexistence of oxygen by using hydrocarbon as reductant. In addition, the practical exhaust gas purification catalyst was also developed for lean-burn engines by combining noble metal catalysts with NOx absorbing materials or zeolite superior in reductant adsorbing power. {epsilon}-caprolactam as raw material of nylon 6 is synthesized from cyclohexanoneoxime through Beckmann` rearrangement reaction. Zeolite system solid catalysts using no ammonia are under investigation. An environment-friendly synthesis method using not phosgene but catalyst was proposed for production of dimethyl carbonate. How to utilize catalysts for global material circulation remains unsolved for the future study. 5 refs.

  1. Spatial heterogeneities within an individual catalyst particle during reaction as revealed by in-situ micro-spectroscopy

    Kox, M.H.F.


    Heterogeneous catalysts are solids, which are of fundamental importance in (petro-) chemical, pharmaceutical and environmental industries. The majority (> 85%) of all chemicals and transportation fuels have come into contact with at least one catalyst material during their manufacturing process. In


    LIU Qingpu; HOU Sijian; HA Runhua


    The selective water plugging agent was prepared by heating the blends of the polyacrylamide inverse latex, modified urea formaldehyde resin, crosslinking agent and catalysts.The results show that using different types of polymers and additives or changing in their proportion of the blends, the gelling viscosity, starting point of gelling and other properties of the IPN can be controlled.

  3. A Polyphenylene Support for Pd Catalysts with Exceptional Catalytic Activity

    Wang, Feng; Mielby, Jerrik Jørgen; Richter, Felix Herrmann


    We describe a solid polyphenylene support that serves as an excellent platform for metal-catalyzed reactions that are normally carried out under homogeneous conditions. The catalyst is synthesized by palladium-catalyzed Suzuki coupling which directly results in formation of palladium nanoparticles...... confined to a porous polyphenylene network. The composite solid is in turn highly active for further Suzuki coupling reactions, including non-activated substrates that are challenging even for molecular catalysts....

  4. Foundation Flash Catalyst

    Goralski, Greg


    This book offers an introduction to Flash Catalyst for designers with intermediate to advanced skills. It discusses where Catalyst sits within the production process and how it communicates with other programs. It covers all of the features of the Flash Catalyst workspace, teaching you how to create designs from scratch, how to build application designs and add functionality, and how to master the Catalyst/Flex workflow. * Introduces Flash Catalyst * Focuses on production process * Covers the interrelation between Flash Catalyst and Photoshop/Illustrator/Flex/Flash What you'll learn Starting f

  5. Preparation and characterizations of Ce-Cu-O monolithic catalysts for ethyl acetate catalytic combustion

    马瑞红; 苏孝文; 金凌云; 鲁继青; 罗孟飞


    Ce-Cu-O monolithic catalysts were prepared by using Ce0.9Cu0.1O1.9 solid solution or nitrate as precursors,and their catalytic performance for the combustion of ethyl acetate were studied.The catalysts calcined at a low temperature showed high catalytic activities.When calcined at high temperatures,the catalyst with Ce0.9Cu0.1O1.9 solid solution as precursor remained a high activity,while the catalyst with metal nitrates as precursors exhibited a suppressed reactivity.Therefore,the catalyst prepared with th...

  6. Fiber reinforced silicon-containing arylacetylene resin composites


    Full Text Available A silicon-containing arylacetylene resin (SAR, a poly(dimethylsilyleneethynylene phenyleneethynylene (PMSEPE, was synthesized. The PMSEPE is a solid resin at ambient temperature with a softening temperature about 60°C and soluble in some solvents like tetrahydrofuran. The melt viscosity of the PMSEPE resin is less than 1 Pa•s. The resin could cure at the temperature of lower than 200°C. Fiber reinforced PMSEPE composites were prepared from prepregs which were made by the impregnation of fibers in PMSEPE resin solution. The composites exhibit good mechanical properties at room temperature and 250°C. The observation on fracture surfaces of the composites reinforced by glass fibers and carbon fibers demonstrates that the adhesion between the fibers and resin is good. The results from an oxyacetylene flame test show that the composites have good ablation performance and XRD analyses indicate that SiC forms in the residues during the ablation of the composites.

  7. Solid Oxide Fuel Cell


    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...

  8. Solid Oxide Fuel Cell


    The solid oxide fuel cell comprising a metallic support material, an active anode layer consisting of a good hydrocarbon cracking catalyst, an electrolyte layer, an active cathode layer, and a transition layer consisting of preferably a mixture of LSM and a ferrite to the cathode current collector...


    Zhen-zhong Yang; Yuan-ze Xu; De-lu Zhao


    The waterborne dispersions of epoxy resin were prepared by the phase inversion emulsification technique.Rheological behavior and its relationship with the structural change of the systems were studied. It was shown that the concentrated dispersions were highly viscoelastic and pseudoplastic, which was attributed to the formation of a physical network among the waterborne particles via hydrogen bond. The dilute dispersions were Newtonian fluids. The discrete clusters composed of small waterborne particles were found in diluted dispersions. With increasing solid content, there existed a structural transition via percolation through a cluster-cluster aggregation mode to form the physical network, which was qualitatively evidenced by the TEM morphologies.``

  10. Biodiesel production from waste cooking oil using a heterogeneous catalyst from pyrolyzed rice husk.

    Li, Ming; Zheng, Yan; Chen, Yixin; Zhu, Xifeng


    A solid acid catalyst was prepared by sulfonating pyrolyzed rice husk with concentrated sulfuric acid, and the physical and chemical properties of the catalyst were characterized in detail. The catalyst was then used to simultaneously catalyze esterification and transesterification to produce biodiesel from waste cooking oil (WCO). In the presence of the as-prepared catalyst, the free fatty acid (FFA) conversion reached 98.17% after 3h, and the fatty acid methyl ester (FAME) yield reached 87.57% after 15 h. By contrast, the typical solid acid catalyst Amberlyst-15 obtained only 95.25% and 45.17% FFA conversion and FAME yield, respectively. Thus, the prepared catalyst had a high catalytic activity for simultaneous esterification and transesterification. In addition, the catalyst had excellent stability, thereby having potential use as a heterogeneous catalyst for biodiesel production from WCO with a high FFA content. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Effect of vanadium on the deactivation of FCC catalysts

    Roncolatto, R.E.; Lam, Y.L. [PETROBRAS, Rio de Janeiro, RJ (Brazil). Centro de Pesquisas. Div. de Catalisadores]. E-mail:;


    This work provides concrete evidence that causes the destruction of the zeolite in the FCC catalysts by a mechanism of acid attack or solid-solid transformation, as well as additional dealumination of the zeolite framework in the presence of steam and at high temperature. While these effects resulted in the reduction in crystallinity (zeolite Y content), specific area and unit cell size of the Y zeolite as the amount of vanadium in the catalysts increased, the reduction in activity was the most pronounced. The differences in these behaviors were interpreted and the model can be used for better catalyst formulation or screening. (author)


    Roncolatto R.E


    Full Text Available This work provides concrete evidence that vanadium causes the destruction of the zeolite in the FCC catalysts by a mechanism of acid attack or solid-solid transformation, as well as additional dealumination of the zeolite framework in the presence of steam and at high temperature. While these effects resulted in the reduction in crystallinity (zeolite Y content, specific area and unit cell size of the Y zeolite as the amount of vanadium in the catalysts increased, the reduction in activity was the most pronounced. The differences in these behaviors were interpreted and the model can be used for better catalyst formulation or screening.

  13. Resin composite repair: Quantitative microleakage evaluation of resin-resin and resin-tooth interfaces with different surface treatments.

    Celik, Cigdem; Cehreli, Sevi Burcak; Arhun, Neslihan


    The aim was to evaluate the effect of different adhesive systems and surface treatments on the integrity of resin-resin and resin-tooth interfaces after partial removal of preexisting resin composites using quantitative image analysis for microleakage testing protocol. A total of 80 human molar teeth were restored with either of the resin composites (Filtek Z250/GrandioSO) occlusally. The teeth were thermocycled (1000×). Mesial and distal 1/3 parts of the restorations were removed out leaving only middle part. One side of the cavity was finished with course diamond bur and the other was air-abraded with 50 μm Al2O3. They were randomly divided into four groups (n = 10) to receive: Group 1: Adper Single Bond 2; Group 2: All Bond 3; Group 3: ClearfilSE; Group 4: BeautiBond, before being repaired with the same resin composite (Filtek Z250). The specimens were re-thermocycled (1000×), sealed with nail varnish, stained with 0.5% basic fuchsin, sectioned mesiodistally and photographed digitally. The extent of dye penetration was measured by image analysis software (ImageJ) for both bur-finished and air-abraded surfaces at resin-tooth and resin-resin interfaces. The data were analyzed statistically. BeautiBond exhibited the most microleakage at every site. Irrespective of adhesive and initial composite type, air-abrasion showed less microleakage except for BeautiBond. The type of initial repaired restorative material did not affect the microleakage. BeautiBond adhesive may not be preferred in resin composite repair in terms of microleakage prevention. Surface treatment with air-abrasion produced the lowest microleakage scores, independent of the adhesive systems and the pre-existing resin composite type. Pre-existing composite type does not affect the microleakage issue. All-in-one adhesive resin (BeautiBond) may not be preferred in resin composite repair in terms of microleakage prevention.

  14. Rheology Analysis of Thermosetting Resin Candidates for Use in Fuel Compacting

    Trammell, Michael P. [ORNL


    The AGR-1 and AGR-2 overcoating and compacting method utilized a wet mixing process where liquid resin (Hexion Durite SC-1008) was blended with natural and synthetic graphite to produce a graphite/resin matrix for overcoating. The matrix production method specified in the scale-up plan is a co-grinding jet mill process where powdered resin and graphite are fed at the same time into a jet mill. Because of the change in matrix production style, SC-1008 cannot be used in the jet milling process because it is a liquid. Also, attempts to dry out matrix made with SC-1008 for use in the overcoating process at B&W had mixed results. The SC-1008 resin became tacky when dried which caused the matrix to build up inside the overcoater. The scale- up jet milling/mixing and overcoating processes required that a suite of solid or powdered resins be identified. Suitable resins candidates were down selected to two resins, specifically Plenco 14838 and Hexion SD-1708. These resins are referred to as novolac or “two-stage” resins because they require the addition of a curing agent such as hexamethylenetetramine (Hexa) to promote an increased level of cross linking. The overcoating matrix is made of 3 components; natural graphite, synthetic graphite, and resin. The most influential component of the compacting process is the resin component and how it behaves with regards to time, temperature, and pressure. The selected scale-up resins are considered fast curing which means that the increase in molecular weight (curing) occurs over a relatively short period of time, ranging from a few seconds to several minutes depending on the temperature. To find the optimal compacting conditions it is useful to quantify this behavior. In this report, rheology is used to investigate viscosity as a function of time at specific temperatures for the previously mentioned resins.

  15. System for removing contaminants from plastic resin

    Bohnert, George W.; Hand, Thomas E.; DeLaurentiis, Gary M.


    A resin recycling system that produces essentially contaminant-free synthetic resin material in an environmentally safe and economical manner. The system includes receiving the resin in container form. A grinder grinds the containers into resin particles. The particles are exposed to a solvent in one or more solvent wash vessels, the solvent contacting the resin particles and substantially removing contaminants on the resin particles. A separator is used to separate the resin particles and the solvent. The resin particles are then placed in solvent removing element where they are exposed to a solvent removing agent which removes any residual solvent remaining on the resin particles after separation.

  16. Design of heterogeneous catalysts

    Frey, Anne Mette

    was inspired by a computational screening, suggesting that alloys such as Ni-Fe, Co-Ni, and Co-Fe should show superior activity to the industrially used nickel catalyst. Especially the Ni-Fe system was considered to be interesting, since such alloy catalysts should be both more active and cheaper than the Ni...... well, and the best catalyst prepared had a C5+ yield almost a factor of two higher than a standard air calcined Co catalyst. In the NH3-SCR reaction it is desirable to develop an active and stable catalyst for NOx removal in automotive applications, since the traditionally used vanadium-based catalyst...... pose an environmental risk. The focus was put on iron-containing zeolite catalysts, since these recently have shown great potential as catalysts for the process. A number of different zeolites were compared. BEA was found to be the most active, thus focus was put on this material. Different preparation...

  17. Flame Retardant Epoxy Resins

    Thompson, C. M.; Smith, J. G., Jr.; Connell, J. W.; Hergenrother, P. M.; Lyon, R. E.


    As part of a program to develop fire resistant exterior composite structures for future subsonic commercial aircraft, flame retardant epoxy resins are under investigation. Epoxies and their curing agents (aromatic diamines) containing phosphorus were synthesized and used to prepare epoxy formulations. Phosphorus was incorporated within the backbone of the epoxy resin and not used as an additive. The resulting cured epoxies were characterized by thermogravimetric analysis, propane torch test, elemental analysis and microscale combustion calorimetry. Several formulations showed excellent flame retardation with phosphorous contents as low as 1.5% by weight. The fracture toughness of plaques of several cured formulations was determined on single-edge notched bend specimens. The chemistry and properties of these new epoxy formulations are discussed.

  18. When magnetic catalyst meets magnetic reactor: etherification of FCC light gasoline as an example.

    Cheng, Meng; Xie, Wenhua; Zong, Baoning; Sun, Bo; Qiao, Minghua


    The application of elaborately designed magnetic catalysts has long been limited to ease their separation from the products only. In this paper, we for the first time employed a magnetic sulphonated poly(styrene-divinylbenzene) resin catalyst on a magnetically stabilized-bed (MSB) reactor to enhance the etherification of fluidized catalytic cracking (FCC) light gasoline, one of the most important reactions in petroleum refining industry. We demonstrated that the catalytic performance of the magnetic acid resin catalyst on the magnetic reactor is substantially enhanced as compared to its performance on a conventional fixed-bed reactor under otherwise identical operation conditions. The magnetic catalyst has the potential to be loaded and unloaded continuously on the magnetic reactor, which will greatly simplify the current complex industrial etherification processes.

  19. Effective Liquid-phase Nitration of Benzene Catalyzed by a Stable Solid Acid Catalyst: Silica Supported Cs{sub 2.5}H{sub 0.5}PMo{sub 12}O{sub 40}

    Gong, Shu-wen; Liu, Li-jun; Zhang, Qian; Wang, Liang-yin [Liaocheng University, Liaocheng (China)


    Silica supported Cs{sub 2.5}H{sub 0.5}PMo{sub 12}O{sub 40} catalyst was prepared through sol-gel method with ethyl silicate-40 as silicon resource and characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy, nitrogen adsorption-desorption and potentiometric titration methods. The Cs{sub 2.5}H{sub 0.5}PMo{sub 12}O{sub 40} particles with Keggin-type structure well dispersed on the surface of silica, and the catalyst exhibited high surface area and acidity. The catalytic performance of the catalysts for benzene liquid-phase nitration was examined with 65% nitric acid as nitrating agent, and the effects of various parameters were tested, which including temperature, time and amount of catalyst, reactants ratio, especially the recycle of catalyst was emphasized. Benzene was effectively nitrated to mononitro-benzene with high conversion (95%) in optimized conditions. Most importantly, the supported catalyst was proved has excellent stability in the nitration progress, and there were no any other organic solvent and sulfuric acid were used in the reaction system, so the liquid-phase nitration of benzene that we developed was an eco-friendly and attractive alternative for the commercial technology

  20. Paramagnetic epoxy resin

    E. C. Vazquez Barreiro


    Full Text Available This work illustrates that macrocycles can be used as crosslinking agents for curing epoxy resins, provided that they have appropriate organic functionalities. As macrocycles can complex metal ions in their structure, this curing reaction allows for the introduction of that metal ion into the resin network. As a result, some characteristic physical properties of the metallomacrocycle could be transferred to the new material. The bisphenol A diglycidyl ether (BADGE, n = 0 and hemin (a protoporphyrin IX containing the Fe(III ion, and an additional chloride ligand have been chosen. The new material has been characterized by differential scanning calorimetry (DSC, thermogravimetric analysis (TGA, Fourier Transform Infrared (FT-IR, Nuclear Magnetic Resonance (NMR, Transmission Electron Microscopy (TEM, and magnetic susceptibility measurements. Fe(III remains in the high-spin state during the curing process and, consequently, the final material exhibits the magnetic characteristics of hemin. The loss of the chlorine atom ligand during the cure of the resin allows that Fe(III can act as Lewis acid, catalyzing the crosslinking reactions. At high BADGE n = 0/hemin ratios, the formation of ether and ester bonds occurs simultaneously during the process.

  1. Selective Dehydration of Sorbitol to Isosorbide over Sulfonated Activated Carbon Catalyst

    Kang, Hyo Yoon; Hwang, Dong Won; Hwang, Young Kyu; Hwang, Jin-Soo; Chang, Jong-San [Korea Research Institute of Chemical Technology (KRICT), Daejeon (Korea, Republic of)


    A sulfonated activated carbon (AC-SO{sub 3}H) was used as a solid acid catalyst for dehydration of sorbitol to isosorbide and its catalytic performance was compared with the commercial solid acid such as acidic ion exchange resin, Amberlyst-36, and sulfated copper oxide. The catalytic performance with 100% sorbitol conversion and 52% isosorbide selectivity was obtained over AC-SO{sub 3}H at 423.15 K. Although AC-SO{sub 3}H possessed only 0.5 mmol/g of sulfur content, it showed the similar dehydration activity of sorbitol to isosorbide with Amberlyst-36 (5.4 mmol/g) at 423.15 K. Based on the high thermal and chemical stability of AC-SO{sub 3}H, one-step reactive distillation, where isosorbide separation can be carried out simultaneously with sorbitol dehydration, was tried to increase the recovery yield of isosorbide from sorbitol. The reactive distillation process using AC-SO{sub 3}H, the turnover number of AC-SO{sub 3}H was 4 times higher than the conventional two-step process using sulfuric acid.

  2. Pd Close Coupled Catalyst

    Zhong Hua SHI; Mao Chu GONG; Yao Qiang CHEN


    A catalyst comprised novel high surface area alumina support was prepared to control emission of automobiles. The results showed that prepared catalyst could satisfy the requirements of a high performance close coupled catalyst for its good catalytic activity at low temperature and good stability at high temperature.

  3. Determination of the gel point of a polyfurfuryl alcohol resin and characterization of its curing rheokinetics

    Dominguez, Juan Carlos; Madsen, Bo


    The determination of the gel point of a resin is a key in order to design and optimize the manufacturing process of composite materials. In this work, the gel point of a biobased polyfurfuryl alcohol (FA) resin has been determined by rheological isothermal tests at different curing temperatures....... The obtained gel times using three different amounts of catalyst (2, 4 and 6 % wt.) were correlated to temperature by the Macosko model; to predict the gel time at any temperature within the studied range. Furthermore, the evolution of the complex viscosity of the FA resin after its gel point has been studied...... of the resin system. The evolution of the viscosity has been modeled using widely used rheokinetic models. Finally, since rheological properties such as viscosity and complex modulus (G*) are highly sensitive to the molecular weight of a polymeric system, and they can be used as indicators of the degree...

  4. Synthesis, Characterization and Glass - Reinforced Composites of Thiourea - Formaldehyde - Phenol Resin

    Kanuprasad Dahyalal Patel


    Full Text Available N,N'-Dimethylol thiourea-formaldehyde (DMTUF resin having the methylol group (CH2OH has been prepared and characterized. The condensation of DMTUF resin with Phenol (P was carried out in the presence of alcoholic alkali catalyst at varying ratios of DMTUF: P, namely 1:1, 1:1.5 and 1:2. The resultant DMTUFP resin was characterized by elemental analysis, IR spectral studies, number average molecular weight ( M¯n estimated by non-aqueous conductometric titration, and thermo gravimetry. The curing study of DMTUFP resin with hexamethylene tetramine (HMTA was monitored by differential scanning calorimetry (DSC and kinetic parameters were evaluated. Glass-reinforced composites based on the DMTUFP-HMTA system have also been prepared and characterized.

  5. Synthesis, Characterization and Glass - Reinforced Composites of N,N'-Dimethylolthiourea – m-Aminophenol Resin

    K. D. Patel


    Full Text Available N,N’-Dimethylolthiourea (DMTU resin having the methylol group ( –CH2 OH has been prepared and characterized. The condensation of DMTU resin with m-aminophenol was carried out in the presence of alcoholic alkali catalyst at varying ratios of DMTU: mAP, namely 1:1, 1:1.5 and 1:2. The resultant DMTUmAP resin was characterized by elemental analysis, IR spectral studies, number average molecular weight (M¯n estimated by non-aqueous conductometric titration, and thermogravimetry. The curing study of DMTUmAP resin with hexamethylenetetramine (HMTA was monitored by differential scanning calorimetry (DSC and kinetic parameters were evaluated. Glass-reinforced composites based on the DMTUmAP-HMTA system have also been prepared and characterized.

  6. Heterogeneous base catalysts for edible palm and non-edible Jatropha-based biodiesel production

    Lee, Hwei Voon; Juan, Joon Ching; Binti Abdullah, Nurul Fitriyah; Nizah MF, Rabiah; Taufiq-Yap, Yun Hin


    Background Transesterification catalyzed by solid base catalyst is a brilliant technology for the noble process featuring the fast reaction under mild reacting condition in biodiesel production. Heterogeneous base catalysts are generally more reactive than solid acid catalysts which require extreme operating condition for high conversion and biodiesel yield. In the present study, synthesis of biodiesel was studied by using edible (palm) or non-edible (Jatropha) feedstock catalyzed by heteroge...

  7. A study of the kinetic, dielectric, and rheological properties of thermosetting resins used in pultruded polymer composites

    Shanku, Reshma

    A comprehensive analysis has been conducted of the curing behavior of AOC VIBRINRTM E-606-6 (medium reactivity isophthalic), E-964 (high reactivity isophthalic), and P-341 (highest reactivity) polyester resins, and Shell EPON 9310 resin/EPON 9360 curing agent/EPON 537 accelerator resin system using calorimetric, dielectric, and rheological methods. The unsaturated polyester resins were cured with two different catalysts at three levels of concentration. Calorimetry and dielectrometry were employed to obtain polyester resin curing properties for the resin formulations studied. Rheological characterization of selected polyester resin formulations and the EPON 9310 resin system were also conducted. Kinetic parameters for all resin formulations were determined using a differential scanning calorimeter (DSC) by dynamic and isothermal methods. The dynamic and isothermal kinetic parameters obtained were used to generate heat flow values which were compared to the experimental DSC heat flow recorded; kinetic parameters that accurately modeled the pultrusion process were selected. The kinetic parameters were used in a numerical model to predict temperatures and degrees of cure under pultrusion processing conditions. The results obtained from the in-situ dielectric tests conducted on the pultruder in the Composites Material Laboratory at the University of Mississippi were compared to the degree of cure predictions from the numerical model and the experimental degree of cure from calorimetric analysis. Prior to the in-situ pultrusion studies, small quantities of resin formulations were tested for their dielectric cure properties when heated in an oven simulating pultrusion processing temperatures and rate of heating. This technique allowed small quantities of resins to be tested for degrees of cure. It was determined that such screening tests can be effectively conducted and can aid in pultrusion process planning. Complex viscosity profiles until gelation were generated for

  8. Dry PMR-15 Resin Powders

    Vannucci, Raymond D.; Roberts, Gary D.


    Shelf lives of PMR-15 polymides lengthened. Procedure involves quenching of monomer reactions by vacuum drying of PRM-15 resin solutions at 70 to 90 degree F immediately after preparation of solutions. Absence of solvent eliminates formation of higher esters and reduces formation of imides to negligible level. Provides fully-formulated dry PMR-15 resin powder readily dissolvable in solvent at room temperature immediately before use. Resins used in variety of aerospace, aeronautical, and commercial applications.

  9. Design and manufacture of Dialog~R Occlusion solid composite resin adhering bridge for repairing single tooth missing%Dialog~R Occlusion硬质树脂黏接桥制作及对单个牙缺失的固定修复

    郭莉; 任肖华; 王晓洁; 孟慧萍; 李文荟; 薛鹏


    OBJECTIVE: Resin adhering bridge alone is still controversial in clinical application. This study was designed to manufacture Dialog~R Occlusion solid composite resin adhering bridge so as to observe the repairing effect on single tooth missing. METHODS: The scaffold of Dialog~R Occlusion solid composite resin adhering bridge was made by glass fiber and Dialog~R and Dialog Occlusal" resin. A total of 43 patients with single tooth missing were accepted repairing surgery using solid composite resin adhering bridge. The occlusive space of 17 patients was wider than 0.5 mm, the undercut of abutment tooth space was stripped, marginal ridge of proximal and distal abutment tooth near tongue was stripped to a small quantity; and abutment tooth near tongue was polished using rubber cup. 0.8-1.2 mm tooth tissues of front teeth near tongue, bicuspid tooth, and the first axletooth near tongue (palatum) was stripped, gum edge was stripped roundly, a 1-mm incisal margin was cut at 1.0-1.5 mm from gum. RESULTS: During a follow-up of 6-62 months, 39 out of 43 patients were rechecked, and the follow-up rate was 90.7%. All the prosthetic replacements were well without loosening, damage and breakage. Abrasion was not observed at the incisal margin of 35 patients. However, the incisal margin of 4 patients was a little abrasion and shortened 0.1-0.5 mm, but the color was not changed. The prosthetic replacement surface was smooth, the edge was closed well, and secondary caries was not checked on abutment tooth. Therefore, the clinical effect was satisfactory. CONCLUSION: Dialog" Occlusion solid composite resin adhering bridge is an ideal method to repair single tooth missing, characterizing by less damage, no metal, beautiful outlook, high achievement ratio of adhering, strong mechanical function, and simple operation.%目的:目前单纯树脂黏接桥一直是较有争议的黏接材料.设计并制作纤维加强的Dialog~R Occlusion硬质树脂黏接桥,并观察其对单个牙缺

  10. Role of clay as catalyst in Friedel–Craft alkylation

    Tanushree Choudhury; Nirendra M Misra


    Solid acids have become increasingly important for many liquid-phase industrial reactions these days. Montmorillonite clays (2:1 clay mineral) have been used as efficient solid acid catalysts for a number of organic and liquid phase reactions and offer several advantages over classic acids. Tailor made catalysts can be prepared from clays by suitably adjusting their acidity and surface area by acid activation. In the present work, preparation, characterization and performance of Pt (II) clays, Cu (II) clays, acid clay, and sol–gel hybrids of Cu (II) clays as solid catalysts in a test Friedel–Craft alkylation reaction of benzyl chloride with toluene using differential scanning calorimeter (DSC) are reported. Product formation has been analysed by FTIR spectroscopy. The main objective of this work is to show how clay as a solid catalyst affects reaction rates and activation energies. Acidity and dispersion of solid catalysts are twomain factors which govern a catalysis reaction. Kinetic parameter analysis and XRD studies confirm that acid Pt (II) clay and Pt (II) clay dispersed by natural dispersants aremore effective catalysts. In contrast to the reactions using AlCl3, the experimental conditions are non-polluting and the final work up does not require any aqueous treatment.

  11. Solid-supported synthesis of 5'-mRNA CAP-4 from Trypanosomatids.

    Lewdorowicz, Magdalena; Jemielity, Jacek; Kierzek, Ryszard; Shapira, Michal; Stepinski, Janusz; Darzynkiewicz, Edward


    The unique structure of 5' mRNA cap from Trypanosomatids is the most modified cap found in nature. Here we present the synthesis of cap-4 (m(7)Gpppm(3)(6,6,2')Apm(2')Apm(2')Cpm(2)(3,2')Up) on a disulfide-tethered solid support. This approach allows obtaining cap-4 more efficiently then previously described. Moreover such modified resin could be a useful tool for affinity purification of Leishmania proteins interacting with cap-4. For the final step of synthesis, namely coupling of phosphorylated tetranucleotide with activated 7-methylguanosine 5'-diphosphate two systems were compared. Surprisingly, the coupling in water with Mn(2+) as a catalyst, gave better results than usually more effective coupling in DMF with ZnCl(2).

  12. Resin regeneration device for condensate desalter

    Segawa, Yoshihiro [Toshiba Engineering Co. Ltd., Kawasaki, Kanagawa (Japan); Hirose, Yuki


    The present invention provides a resin regeneration device for a condensate desalter of a nuclear power plant. Namely, both anionic and cationic exchange resins are supplied in a mixed state from a forwarding water desalting tower to an anionic resin regeneration tower. In the anionic resin generation tower, the resin is once separated to an anionic exchange region layer, a mixed resin layer and an cationic exchange resin layer in this order from the upper portion by water injected from a stirring water injection tube disposed at the bottom. Then, water is injected from a developing water injection tube disposed at the lower portion of the mixed resin layer to develop the cationic exchange resin layer and the mixed resin layer to the upper portion of the cationic resin regeneration tower. Subsequently, the amount of the injection of the developing water is reduced to such a flow rate that only the anionic exchange resin is precipitated. Then, a cationic exchange resin layer is formed at the upper portion and an anion exchange resin layer is formed at the lower portion of the developing water injection tube of the cationic resin regeneration tower. The anionic exchange resin is transferred to the anionic exchange resin regeneration tower in this state. According to the present invention, the mixed resin layer can be separated to anionic and cationic exchange resins easily and reliably. (I.S.)

  13. Synthesis and Characterization of Bio-Oil Phenol Formaldehyde Resin Used to Fabricate Phenolic Based Materials.

    Cui, Yong; Hou, Xiaopeng; Wang, Wenliang; Chang, Jianmin


    In this study, bio-oil from the fast pyrolysis of renewable biomass was used as the raw material to synthesize bio-oil phenol formaldehyde (BPF) resin-a desirable resin for fabricating phenolic-based material. During the synthesis process, paraformaldehyde was used to achieve the requirement of high solid content and low viscosity. The properties of BPF resins were tested. Results indicated that BPF resin with the bio-oil addition of 20% had good performance on oxygen index and bending strength, indicating that adding bio-oil could modify the fire resistance and brittleness of PF resin. The thermal curing behavior and heat resistance of BPF resins were investigated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Results showed that adding bio-oil had an impact on curing characteristics and thermal degradation process of PF resin, but the influence was insignificant when the addition was relatively low. The chemical structure and surface characteristics of BPF resins were determined by Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM). The analysis demonstrated that adding bio-oil in the amount of 20% was able to improve the crosslinking degree and form more hydrocarbon chains in PF resin.

  14. Germanium nanowires grown using different catalyst metals

    Gouveia, R.C., E-mail: [Departamento de Física – NanO Lab, Universidade Federal de São Carlos, Rod. Washington Luís, Km 235 – SP 310, São Carlos, CEP 13565-905 (Brazil); Área de Ciências, Instituto Federal de Educação Ciência e Tecnologia de São Paulo, Rua Américo Ambrósio, 269, Jd. Canaã, Sertãozinho, CEP 14169-263 (Brazil); Kamimura, H.; Munhoz, R.; Rodrigues, A.D. [Departamento de Física – NanO Lab, Universidade Federal de São Carlos, Rod. Washington Luís, Km 235 – SP 310, São Carlos, CEP 13565-905 (Brazil); Leite, E.R. [Departamento de Química – LIEC, Universidade Federal de São Carlos, São Carlos, CEP 13565-905 (Brazil); Chiquito, A.J. [Departamento de Física – NanO Lab, Universidade Federal de São Carlos, Rod. Washington Luís, Km 235 – SP 310, São Carlos, CEP 13565-905 (Brazil)


    Germanium nanowires have been synthesized by the well known vapor-liquid-solid growth mechanism using gold, silver, cooper, indium and nickel as catalyst metals. The influence of metal seeds on nanowires structural and electronic transport properties was also investigated. Electron microscopy images demonstrated that, despite differences in diameters, all nanowires obtained presented single crystalline structures. X-ray patterns showed that all nanowires were composed by germanium with a small amount of germanium oxide, and the catalyst metal was restricted at the nanowires' tips. Raman spectroscopy evidenced the long range order in the crystalline structure of each sample. Electrical measurements indicated that variable range hopping was the dominant mechanism in carrier transport for all devices, with similar hopping distance, regardless the material used as catalyst. Then, in spite of the differences in synthesis temperatures and nanowires diameters, the catalyst metals have not affected the composition and crystalline quality of the germanium nanowires nor the carrier transport in the germanium nanowire network devices. - Highlights: • Ge nanowires were grown by VLS method using Au, Ag, Cu, In and Ni as catalysts. • All nanowires presented high single crystalline quality and long range order. • Devices showed semiconducting behavior having VRH as dominant transport mechanism. • The metal catalyst did not influence structural properties or the transport mechanism.

  15. Alkyd-amino resins based on waste PET for coating applications.

    Torlakoğlu, A; Güçlü, G


    Waste polyethylene terephthalate (PET) flakes were depolymerized by using propylene glycol (PG) in the presence of zinc acetate as catalyst. Glycolysis reaction products of waste PET obtained by using PET/glycol molar ratio 1/2. Two short oil alkyd resins of high acid values (30-40mgKOH/g) were prepared from phthalic anhydride (PA), glycerin (G), coconut oil fatty acids (COFA) and glycolyzed products of waste PET (PET-based alkyd resins) or glycols (PG) (reference alkyd resins). These alkyd resins were blended with 30%, 40%, and 50% of a commercial urea-formaldehyde, melamine-formaldehyde and urea-formaldehyde/melamine-formaldehyde mixture (1/1 weight ratio) and heated at 140 degrees C. The physical and chemical properties such as drying time, hardness, abrasion resistance, adhesion strength, water resistance, alkaline resistance, acid resistance, gelation time, and thermal oxidative degradation resistance (with thermogravimetric analysis, TGA) of these alkyd-amino resins were investigated. The properties of the waste PET-based resins were found to be compatible with the properties of the reference resins.

  16. Synthesis of sulfonated porous carbon nanospheres solid acid by a facile chemical activation route

    Chang, Binbin, E-mail:; Guo, Yanzhen; Yin, Hang; Zhang, Shouren; Yang, Baocheng, E-mail:


    Generally, porous carbon nanospheres materials are usually prepared via a template method, which is a multi-steps and high-cost strategy. Here, we reported a porous carbon nanosphere solid acid with high surface area and superior porosity, as well as uniform nanospheical morphology, which prepared by a facile chemical activation with ZnCl{sub 2} using resorcinol-formaldehyde (RF) resins spheres as precursor. The activation of RF resins spheres by ZnCl{sub 2} at 400 °C brought high surface area and large volume, and simultaneously retained numerous oxygen-containing and hydrogen-containing groups due to the relatively low processing temperature. The presence of these functional groups is favorable for the modification of –SO{sub 3}H groups by a followed sulfonation treating with sulphuric acid and organic sulfonic acid. The results of N{sub 2} adsorption–desorption and electron microscopy clearly showed the preservation of porous structure and nanospherical morphology. Infrared spectra certified the variation of surface functional groups after activation and the successful modification of –SO{sub 3}H groups after sulfonation. The acidities of catalysts were estimated by an indirect titration method and the modified amount of –SO{sub 3}H groups were examined by energy dispersive spectra. The results suggested sulfonated porous carbon nanospheres catalysts possessed high acidities and –SO{sub 3}H densities, which endowed their significantly catalytic activities for biodiesel production. Furthermore, their excellent stability and recycling property were also demonstrated by five consecutive cycles. - Graphical abstract: Sulfonated porous carbon nanospheres with high surface area and superior catalytic performance were prepared by a facile chemical activation route. - Highlights: • Porous carbon spheres solid acid prepared by a facile chemical activation. • It owns high surface area, superior porosity and uniform spherical morphology. • It possesses

  17. Quantitative analysis of PMR-15 polyimide resin by HPLC

    Roberts, Gary D.; Lauver, Richard W.


    The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

  18. Quantitative analysis of PMR-15 polyimide resin by HPLC

    Roberts, Gary D.; Lauver, Richard W.


    The concentration of individual components and of total solids of 50 wt pct PMR-15 resin solutions was determined using reverse-phase HPLC to within + or - 8 percent accuracy. Acid impurities, the major source of impurities in 3,3', 4,4'-benzophenonetetracarboxylic acid (BTDE), were eliminated by recrystallizing the BTDE prior to esterification. Triester formation was not a problem because of the high rate of esterification of the anhydride relative to that of the carboxylic acid. Aging of PMR-15 resin solutions resulted in gradual formation of the mononadimide and bisnadimide of 4,4'-methylenedianiline, with the BTDE concentration remaining constant. Similar chemical reactions occurred at a reduced rate in dried films of PMR-15 resin.

  19. Catalytic wet peroxide oxidation of p-nitrophenol by Fe (III) supported on resin.

    Liou, Rey-May; Chen, Shih-Hsiung; Huang, Cheng-Hsien; Lai, Cheng-Lee; Shih, C Y; Chang, Jing-Song; Hung, Mu-Ya


    Fe(III) supported on resin (Fe(III)-resin) as an effective catalyst for peroxide oxidation was prepared and applied for the degradation of p-nitrophenol (PNP). Catalytic wet peroxide oxidation (CWPO) experiments with hydrogen peroxide as oxidant were performed in a batch rector with p-nitrophenol as the model pollutant. Under given conditions (PNP concentration 500 mg/L, H(2)O(2) 0.1 M, 80°C, resin dosage 0.6% g/mL), p-nitrophenol was almost completely removed, corresponding to an 84% of COD removal. It was found that the reaction temperature, oxidant concentration. and initial pH of solution significantly affected both p-nitrophenol conversion and COD removal by oxidation. It can be inferred from the experiments that Fe(III) supported on resin was an effective catalyst in the mineralization of p-nitrophenol. In an acidic environment of oxidation, the leaching test showed that there was only a slight leaching effect on the activity of catalytic oxidation. It was also confirmed by the aging test of catalysts in the oxidation.

  20. Aminolysis of resin-bound N-nosylaziridine-2-carboxylic acids

    Olsen, Christian A; Christensen, Caspar; Nielsen, Birgitte;


    [Structure: see text] Solid-phase synthesis is a rapidly developing area of organic chemistry, of particular importance for medicinal chemistry and chemical biology. Aziridines have previously only rarely been applied in solid-phase synthesis. In the present work, aminolysis of resin-bound, spring...