Publications 2019

Publications 20192023-03-08T18:43:25+01:00

Publications (2019)

Publications sorted by date descending

Synthesis of a germanosilicate zeolite HPM-12 using a short imidazolium-based dication: structure-direction by charge-to-charge distance matching

Authors: Lu, P; Gomez-Hortiguela, L; Gao, ZH; Camblor, MA

Article.
Dalton Trans.. vol: 48. page: 1477-9226.
Date: DEC 28. 2019.
Doi: 10.1039/c9dt04089g.

Abstract:
A short imidazolium based dication, with only three methylene units in the spacer linker, selectively directs the crystallization of zeolite HPM-12 (*UOE) as long as there is enough germanium present in the synthesis gel. The integrity of the dication is proved by dissolution of the zeolite and H-1 and C-13 NMR spectroscopy, where significant effects of organic dication concentration and the presence and concentration of HF need to be taken into account. For the as-made HPM-12 zeolite, a large shift of 9 ppm [read more]

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Effect of oxygen addition, reaction temperature and thermal treatments on syngas production from biogas combined reforming using Rh/alumina catalysts

Authors: Navarro-Puyuelo, A; Reyero, I; Moral, A; Bimbela, F; Banares, MA; Gandia, LM

Article.
J. Ind. Eng. Chem.. vol: 80. page: 1226-086X.
Date: DEC 25. 2019.
Doi: 10.1016/j.jiec.2019.07.051.

Abstract:
Dry reforming and partial oxidation of biogas were studied using 0.5 wt.% Rh/Al2O3 catalysts, both inhouse prepared and commercial. The effects of O-2 addition on syngas yield and biogas conversion were studied at 700 degrees C using different O-2/CH4 ratios in the gas feeding stream: 0 (dry reforming), 0.12, 0.25, 0.45 and 0.50. The highest CH4 conversion, H-2 yield and H-2/CO molar ratio were obtained with an O-2/CH4 ratio of 0.45, even though simultaneous valorization of both [read more]

Hydrotreating of Guaiacol and Acetic Acid Blends over Ni2P/ZSM-5 Catalysts: Elucidating Molecular Interactions during Bio-Oil Upgrading

Authors: Gutierrez-Rubio, S; Moreno, I; Serrano, DP; Coronado, JM

Article.
ACS Omega. vol: 4. page: 2470-1343.
Date: DEC 17. 2019.
Doi: 10.1021/acsomega.9b03221.

Abstract:
Catalytic hydrodeoxygenation (HDO) is an effective technology for upgrading pyrolysis bio-oils. Although, in the past years, this process has been extensively studied, the relevance of the cross-reactivity between the numerous chemical components of bio-oil has been scarcely explored. However, molecular coupling can be beneficial for improving the bio-oil characteristics. With the aim of gaining a better understanding of these interactions, this work investigates the catalytic hydrodeoxygenation of mixtures of two typical components of pyrolysis bio-oils: guaiacol and acetic acid. The catalytic tests were [read more]

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Upgrading the Properties of Reduced Graphene Oxide and Nitrogen-Doped Reduced Graphene Oxide Produced by Thermal Reduction toward Efficient ORR Electrocatalysts

Authors: Ramirez-Barria, CS; Fernandes, DM; Freire, C; Villaro-Abalos, E; Guerrero-Ruiz, A; Rodriguez-Ramos, I

Article.
Nanomaterials. vol: 9. page: .
Date: DEC. 2019.
Doi: 10.3390/nano9121761.

Abstract:
N-doped (NrGO) and non-doped (rGO) graphenic materials are prepared by oxidation and further thermal treatment under ammonia and inert atmospheres, respectively, of natural graphites of different particle sizes. An extensive characterization of graphene materials points out that the physical properties of synthesized materials, as well as the nitrogen species introduced, depend on the particle size of the starting graphite, the reduction atmospheres, and the temperature conditions used during the exfoliation treatment. These findings indicate that it is possible to tailor properties [read more]

g-C3N4/TiO2 composite catalysts for the photo-oxidation of toluene: Chemical and charge handling effects

Authors: Caudillo-Flores, U; Munoz-Batista, MJ; Luque, R; Fernandez-Garcia, M; Kubacka, A

Article.
Chem. Eng. J.. vol: 378. page: 1385-8947.
Date: DEC 15. 2019.
Doi: 10.1016/j.cej.2019.122228.

Abstract:
The interaction between carbon nitride and titania in g-C3N4/TiO2 materials is analyzed from a new perspective. The composite materials are prepared using a well crystallized anatase substrate over which carbon nitride (0.5-4 wt%, promoted or not with Mn) is deposited. The catalysts are characterized using a multitechnique approach. In addition, a kinetic formalism using a rigorous intrinsic expression of light was developed in order to reveal information concerning the chemical and charge carrier effects occurring in the materials. Together with [read more]

Nanosized-bulk V-containing mixed-oxide catalysts: a strategy for the improvement of the catalytic materials properties

Authors: Lopez-Medina, R; Guerrero-Perez, MO; Banares, MA

Article.
New J. Chem.. vol: 43. page: 1144-0546.
Date: DEC 7. 2019.
Doi: 10.1039/c9nj01637f.

Abstract:
A series of nanosized-bulk-supported Mo-V-Nb-Te catalysts was prepared. Using a new synthesis approach, nanocrystalline aggregates of the active phase were deposited on a support. This resulted in the formation of active and selective catalysts for propane oxidation in the acrylic acid reaction, which required a low amount of the active phase. In addition, the catalysts exhibit better mechanical properties and are more economical than their bulk counterparts. The presence of the nanocrystalline domains of the Mo-V-Te-Nb-O active phases (M1, M2 and rutile) for the [read more]

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Insights on the electrooxidation of ethanol with Pd-based catalysts in alkaline electrolyte

Authors: Torrero, J; Montiel, M; Pena, MA; Ocon, P; Rojas, S

Article.
Int. J. Hydrog. Energy. vol: 44. page: 0360-3199.
Date: DEC 6. 2019.
Doi: 10.1016/j.ijhydene.2019.10.124.

Abstract:
In this work, we report a facile method of synthesis of carbon supported Pd, PdRu, and PdNi nanoparticles, and a comparative study of their catalytic behavior for the electrooxidation of ethanol in alkaline media. The addition of metals such as Ru or Ni increases the oxophilicity of the Pd surface, as observed from the shifting of the Pd oxide reduction peaks. As a consequence, the onset potential for the electrooxidation of ethanol shifts to less positive values on the [read more]

Upgrading the Properties of Reduced Graphene Oxide and Nitrogen-Doped Reduced Graphene Oxide Produced by Thermal Reduction toward Efficient ORR Electrocatalysts

Authors: Ramirez-Barria, CS; Fernandes, DM; Freire, C; Villaro-Abalos, E; Guerrero-Ruiz, A; Rodriguez-Ramos, I

Article.
Nanomaterials. vol: 9. page: .
Date: DEC. 2019.
Doi: 10.3390/nano9121761.

Abstract:
N-doped (NrGO) and non-doped (rGO) graphenic materials are prepared by oxidation and further thermal treatment under ammonia and inert atmospheres, respectively, of natural graphites of different particle sizes. An extensive characterization of graphene materials points out that the physical properties of synthesized materials, as well as the nitrogen species introduced, depend on the particle size of the starting graphite, the reduction atmospheres, and the temperature conditions used during the exfoliation treatment. These findings indicate that it is possible to tailor properties [read more]

Modulation of Lecitase properties via immobilization on differently activated Immobead-350: Stabilization and inversion of enantiospecificity

Authors: Pinheiro, MP; Monteiro, RRC; Silva, FFM; Lemos, TLG; Fernandez-Lafuente, R; Goncalves, LRB; dos Santos, JCS

Article.
Process Biochem.. vol: 87. page: 1359-5113.
Date: DEC. 2019.
Doi: 10.1016/j.procbio.2019.08.016.

Abstract:
Lecitase Ultra (Leci) was immobilized on Immobead-350 (IB-350) activated with epoxy (EPO), amino-divinylsulfone (DVS) or amino-glutaraldehyde (GLU) groups. Leci-GLU had 27% more activity versus p-nitro-phenyl butyrate (p-NPB) than Leci-EPO, after 3 h of immobilization using 100 mg of enzyme/g of support (immobilization yield was 84.1%, expressed activity versus p-NPB was around 10%), the covalent immobilization was show for Leci-GLU and Leci-DVS. After 10 consecutive cycles of p-NPB hydrolysis, its activity remained unaltered. Leci-GLU was the most stable [read more]

Reductive Amination of Ketones with Benzylamine Over Gold Supported on Different Oxides

Authors: Kolobova, E; Maki-Arvela, P; Pestryakov, A; Pakrieva, E; Pascual, L; Smeds, A; Rahkila, J; Sandberg, T; Peltonen, J; Murzin, DY

Article.
Catal. Lett.. vol: 149. page: 1011-372X.
Date: DEC. 2019.
Doi: 10.1007/s10562-019-02917-1.

Abstract:
Reductive amination of cyclohexanone with benzylamine was investigated at 100 degrees C under 30 bar hydrogen in toluene with five different gold catalysts prepared by deposition-precipitation method and supported on TiO2, La2O3/TiO2, CeO2/TiO2, La2O3 and CeO2. Size of metallic gold varied in the range of 2.6-3.6 nm. The best catalysts in reductive amination of cyclohexanone with benzylamine were 4 wt% Au/TiO2 and 4 wt% Au/CeO2/TiO2 giving 72% and 79% yield of the [read more]

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Influence of Post-Synthesis Modifications of Ti1-xZrxO2 Nanocrystallites on Their Photocatalytic Activity for Toluene and Methylcyclohexane Degradation

Authors: Hernandez-Alonso, MD; Fresno, F; O’Shea, VAD; Soria, J; Coronado, JM

Article.
J. Nanosci. Nanotechnol.. vol: 19. page: 1533-4880.
Date: DEC. 2019.
Doi: 10.1166/jnn.2019.16738.

Abstract:
The modification of the structural and surface characteristics of Ti1-xZrxO2 nanocrystallites by post-synthesis treatments is revealed as an effective way to enhance their photocatalytic activity. Starting with the same batch of mixed oxide prepared from reverse microemulsions, different photocatalysts have been obtained by either solvothermal treatment, calcination or a combination of both. Extensive physicochemical characterization of the resulting materials shows that solvothermally treated oxides present lower crystallite size and larger surface area, although without previous calcination these samples appear to have [read more]

Direct sulfation of a Zr-based metal-organic framework to attain strong acid catalysts

Authors: Fernandez-Morales, JM; Lozano, LA; Castillejos-Lopez, E; Rodriguez-Ramo, I; Guerrero-Ruiz, A; Zamaro, JM

Article.
Microporous Mesoporous Mat.. vol: 290. page: 1387-1811.
Date: DEC. 2019.
Doi: 10.1016/j.micromeso.2019.109686.

Abstract:
The application of Metal-Organic Frameworks (MOFs) in gas phase heterogeneous catalysis is still not widely spread because of their limited stability under reaction conditions. Obtaining stable acidic MOFs to be used in reactions that demand strong acid sites remains a challenge up to the present time. In this work, it is shown that nanocrystals of Zirconium MOF UiO-66 can be conveniently and easily functionalized through a simple one-pot synthetic approach, i.e. the direct treatment of UiO-66 with ammonium sulfate [read more]

Methanol Synthesis from CO2: A Review of the Latest Developments in Heterogeneous Catalysis

Authors: Guil-Lopez, R; Mota, N; Llorente, J; Millan, E; Pawelec, B; Fierro, JLG; Navarro, RM

Review.
Materials. vol: 12. page: .
Date: DEC. 2019.
Doi: 10.3390/ma12233902.

Abstract:
Technological approaches which enable the effective utilization of CO2 for manufacturing value-added chemicals and fuels can help to solve environmental problems derived from large CO2 emissions associated with the use of fossil fuels. One of the most interesting products that can be synthesized from CO2 is methanol, since it is an industrial commodity used in several chemical products and also an efficient transportation fuel. In this review, we highlight the recent advances in the development of heterogeneous catalysts and [read more]

Extraction of polyphenols and synthesis of new activated carbon from spent coffee grounds

Authors: Ramon-Goncalves, M; Alcaraz, L; Perez-Ferreras, S; Leon-Gonzalez, ME; Rosales-Conrado, N; Lopez, FA

Article.
Sci Rep. vol: 9. page: 2045-2322.
Date: nov-27. 2019.
Doi: 10.1038/s41598-019-54205-y.

Abstract:
A valorization process of spent coffee grounds (SCG) was studied. Thus, a two-stage process, the first stage of polyphenols extraction and synthesis of a carbonaceous precursor and a subsequent stage of obtaining activated carbon (AC) by means of a carbonization process from the precursor of the previous stage, was performed. The extraction was carried out with a hydro-alcoholic solution in a pressure reactor, modifying time, temperature and different mixtures EtOH:H2O. To optimize the polyphenols extraction, a two-level factorial experimental design [read more]

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