Metal-modified sludge-based biochar enhance catalytic capacity: Characteristics and mechanism

Cities are the main contributors to pollution, resource consumption and social inequalities. Therefore, they should play a key role in the path towards a more sustainable scenario in line with SDGs and different Urban Agendas. However, there are still difficulties in their implementation and citizen can play a central role. This paper presents the Urban Action Structures (UAS), understood as entities with a catalytic capacity with respect to innovative urban policies. Methodologically, firstly, a prospective analysis from regional to international level has been developed, making it possible to identify innovative lines of action in the field of sustainable cities. Secondly, the study has focused on identifying and studying UAS that can make it possible to implement the lines of action previously identified. This paper has shown that there are already social structures that can be understood as UAS, since they implement actions aligned with the priorities of the Urban Agenda for the Basque Country and, therefore, of the SDGs. The research concludes that UAS can play a key role in facilitating the implementation of Urban Agendas. Hence, urban policies should favor the generation of UAS, in order to promote long-term urban development and to foster a more sustainable spatial planning.

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Catalytic Conversion of n-C7 Asphaltenes and Resins II into Hydrogen Using CeO2-Based Nanocatalysts

Nanomaterials ◽

10.3390/nano11051301 ◽

2021 ◽

Vol 11 (5) ◽

pp. 1301

Author(s):

Oscar E. Medina ◽

Jaime Gallego ◽

Sócrates Acevedo ◽

Masoud Riazi ◽

Raúl Ocampo-Pérez ◽

...

Keyword(s):

Hydrogen Production ◽

Low Temperatures ◽

Gaseous Mixture ◽

H2 Production ◽

The Other ◽

Hydrogen Release ◽

Catalytic Gasification ◽

Three Samples ◽

Main Decomposition ◽

Catalytic Capacity

This study focuses on evaluating the volumetric hydrogen content in the gaseous mixture released from the steam catalytic gasification of n-C7 asphaltenes and resins II at low temperatures (<230 °C). For this purpose, four nanocatalysts were selected: CeO2, CeO2 functionalized with Ni-Pd, Fe-Pd, and Co-Pd. The catalytic capacity was measured by non-isothermal (from 100 to 600 °C) and isothermal (220 °C) thermogravimetric analyses. The samples show the main decomposition peak between 200 and 230 °C for bi-elemental nanocatalysts and 300 °C for the CeO2 support, leading to reductions up to 50% in comparison with the samples in the absence of nanoparticles. At 220 °C, the conversion of both fractions increases in the order CeO2 < Fe-Pd < Co-Pd < Ni-Pd. Hydrogen release was quantified for the isothermal tests. The hydrogen production agrees with each material’s catalytic activity for decomposing both fractions at the evaluated conditions. CeNi1Pd1 showed the highest performance among the other three samples and led to the highest hydrogen production in the effluent gas with values of ~44 vol%. When the samples were heated at higher temperatures (i.e., 230 °C), H2 production increased up to 55 vol% during catalyzed n-C7 asphaltene and resin conversion, indicating an increase of up to 70% in comparison with the non-catalyzed systems at the same temperature conditions.

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A study of biomimetic system: Exploration of factors modulating the catalytic capacity of glutathione peroxidase mimics

Journal of Molecular Catalysis A Chemical ◽

10.1016/j.molcata.2007.08.003 ◽

2007 ◽

Vol 277 (1-2) ◽

pp. 193-201 ◽

Cited By ~ 15

Author(s):

Zeyuan Dong ◽

Kai Liang ◽

Chunyu Wang ◽

Xin Huang ◽

Shizhong Mao ◽

...

Keyword(s):

Glutathione Peroxidase ◽

Peroxidase Mimics ◽

Catalytic Capacity ◽

Glutathione Peroxidase Mimics

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Immobilization and characterization of porphyrin (P) and its catalytic capacity

Applied Catalysis A General ◽

10.1016/0926-860x(95)80144-8 ◽

1995 ◽

Vol 125 (2) ◽

pp. N19-N19

Keyword(s):

Catalytic Capacity

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Synthesis of NdAlO3 Nanoparticles and Evaluation of the Catalytic Capacity for Biodiesel Synthesis

Nanomaterials ◽

10.3390/nano9111545 ◽

2019 ◽

Vol 9 (11) ◽

pp. 1545 ◽

Cited By ~ 2

Author(s):

Dionicio-Navarrete ◽

Arrieta-Gonzalez ◽

Quinto-Hernandez ◽

Casales-Diaz ◽

Zuñiga-Diaz ◽

...

Keyword(s):

Mass Ratio ◽

Reaction Products ◽

Optimum Conditions ◽

Reaction Conditions ◽

Catalyst Synthesis ◽

Synthesis Of Nanoparticles ◽

Biodiesel Synthesis ◽

Dta Analysis ◽

Optimum Reaction ◽

Catalytic Capacity

Biodiesel synthesis was carried out via heterogeneous catalysis of canola oil with nanoparticles of a mixed oxide based on rare earths. The catalyst synthesis (NdAlO3) was carried out based on the method proposed by Pechini for the synthesis of nanoparticles. Thermogravimetric analysis-differential thermal analysis (TGA-DTA) analysis was performed on the nanoparticle precursor gel in order to establish the optimum conditions for its calcination, with these being of 800 °C over 24 h. A pure NdAlO3 compound with an approximate size of 100 nm was obtained. The products of the transesterification reaction were analyzed using gas chromatography, FTIR, and NMR. The optimum reaction conditions were determined, namely, the temperature effect, reaction time, methanol:oil mass ratio, and recyclability of the catalyst. These studies showed the following optimal conditions: 200 °C, 5 h, methanol:oil mass ratio of 6:1, and a constant decrease in the catalytic activity of the catalyst was observed for up to six reuses, which later remained constant at around a 50% conversion rate. The maximum biodiesel yield obtained with the optimum conditions was around 75%. Analysis of the reaction products showed that the residual oil showed a chemical composition different from that of the source oil, and that both the biodiesel and glycerol obtained were of high purity.

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Evidence for photochemical synthesis of fluoromethane

Journal of Analytical Atomic Spectrometry ◽

10.1039/d0ja00108b ◽

2020 ◽

Vol 35 (9) ◽

pp. 1720-1726

Author(s):

Ralph E. Sturgeon ◽

Enea Pagliano

Keyword(s):

Acetic Acid ◽

Acid Medium ◽

Halogen Atom ◽

Photochemical Synthesis ◽

Atom Transfer ◽

Acetic Acid Medium ◽

Catalytic Capacity

Cu2+ – assisted photomethylation of fluoride in dilute acetic acid medium is suggested to occur by radical halogen atom transfer, with Cu(ii) acting in a catalytic capacity.

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Characterization of Anaerobic Biofilms Growing on Carbon Felt Bioanodes Exposed to Air

Catalysts ◽

10.3390/catal10111341 ◽

2020 ◽

Vol 10 (11) ◽

pp. 1341

Author(s):

Raúl M. Alonso ◽

Guillermo Pelaz ◽

María Isabel San-Martín ◽

Antonio Morán ◽

Adrián Escapa

Keyword(s):

Normal Operation ◽

Carbon Felt ◽

Dissolved Oxygen Concentration ◽

Oxygen Penetration ◽

Long Period ◽

And Performance ◽

Catalytic Capacity ◽

Felt Electrodes

The role of oxygen in anodic biofilms is still a matter of debate. In this study, we tried to elucidate the structure and performance of an electrogenic biofilm that develops on air-exposed, carbon felt electrodes, commonly used in bioelectrochemical systems. By simultaneously recording the current density produced by the bioanode and dissolved oxygen concentration, both inside and in the vicinity of the biofilm, it was possible to demonstrate the influence of a protective aerobic layer present in the biofilm (mainly formed by Pseudomonas genus bacteria) that prevents electrogenic bacteria (such as Geobacter sp.) from hazardous exposure to oxygen during its normal operation. Once this protective barrier was deactivated for a long period of time, the catalytic capacity of the biofilm was severely affected. In addition, our results highlighted the importance of the material’s porous structure for oxygen penetration in the electrode.

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Surface Modified Magnetic Silica Particles for the Immobilization of Laccase and its Use for Pentachlorophenol Removal in Water

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.178-181.657 ◽

2012 ◽

Vol 178-181 ◽

pp. 657-660

Author(s):

Ying Wang ◽

Di Zhang ◽

Xue Li ◽

Bo Li

Keyword(s):

Enzymatic Activity ◽

Aqueous Solutions ◽

Silica Particles ◽

Immobilized Laccase ◽

Metal Chelating ◽

Chelating Ligand ◽

Magnetic Silica ◽

Surface Modified ◽

Catalytic Capacity

Magnetic Cu2+-chelated silica particles using polyacrylamide (PAM) as a metal-chelating ligand were developed and used for the immobilization of laccase by coordination. The particles were characterized by (XRD). The effect of Cu2+ and PAM concentrations on the enzymatic activity and the catalytic capacity for pentachlorophenol (PCP) degradation were evaluated. The results showed that the optimum Cu2+ and PAM concentrations were 0.2 mol/L and 2 g/L, respectively. The immobilized laccase prepared in this work exhibited a good catalytic capacity for PCP removal from aqueous solutions.

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