16 documents found, page 1 of 2
On the characterization and performance of highly dispersed TiO2 nanoparticles ...
Ferreira, Ricardo; Morales-Torres, Sergio; Pastrana-Martínez, Luisa María; Maldonado Hodar, Francisco Jose; Lourenço, João P.; João, Isabel M.Two series of TiO2-based zeolite composites (BEA structures) were prepared by employing a sol–gel method using two different synthesis approaches, i.e., acidic and basic media. Different photocatalytic composites obtained with increasing amounts of TiO2 (10–50 wt%) were thoroughly characterized and subsequently tested in the photooxidation of ethylene in a continuous gas-phase system. Results showed that sol–ge...
Syngas production by bi-reforming of methane on a bimetallic Ni-ZnO doped zeoli...
Cunha, Adelino F.; Morales-Torres, Sergio; Pastrana-Martínez, Luisa M.; Maldonado-Hódar, Francisco J.; Caetano, Nídia S.Ennoblement of carbon dioxide, particularly the one produced by anaerobic digestion or by biomass combustion, is a motivation to develop novel or improving already existing processes. In this context, an interesting idea is to use carbon dioxide combined together with methane and water. Therefore, bi-reforming of methane (BRM) for syngas production appears to be a good choice. In this work, BRM was studied over...
Biomedical-related applications of functionalized nanomaterials
Almeida, Mafalda R.; Neves, Márcia C.; Morales-Torres, Sergio; Freire, Mara G.; Faria, Joaquim L.; Santos-Ebinuma, Valéria C. [UNESP]; Silva, Cláudia G.Made available in DSpace on 2022-04-28T19:50:56Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01; This chapter provides an overview of the use of nanoparticles in the biomedical field. Due to their unique properties, nanomaterials have enabled the development of innovative technologies within the biomedical field, making them a popular topic of research. Nanoparticles (NPs) can be prepared from a wi...
Carbon nanotubes as catalysts for wet peroxide oxidation: the effect of surface...
Martin-Martinez, Maria; Machado, Bruno; Serp, Philippe; Morales-Torres, Sergio; Silva, Adrián; Figueiredo, José; Faria, Joaquim; Gomes, HelderThree magnetic carbon nanotube (CNT) samples, named A30 (N-doped), E30 (undoped) and E10A20 (selectively N-doped), synthesized by catalytic chemical vapor deposition, were modified by introducing oxygenated surface groups (oxidation with HNO3, samples CNT-N), and by heat treatment at 800 °C for the removal of surface functionalities (samples CNT-HT). Both treatments lead to higher specific surface areas. The ac...
The pH effect on the kinetics of 4-nitrophenol removal by CWPO with doped carbo...
Díaz de Tuesta, Jose Luis; Quintanilla, Asunción; Casas, Jose A.; Morales-Torres, Sergio; Faria, Joaquim; Silva, Adrián; Gomes, HelderP, B and N-doped carbon blacks prepared with H3PO4, urea and H3BO3 were tested as catalysts in the wet peroxide oxidation of a concentrated 4-nitrophenol (4-NP) model solution (C4-NP=5 g·L−1). The highest catalytic activity was found for P-doped carbon black (complete removal of 4-NP after 4 h at 80 °C, Ccat=2.5 g·L−1, CH2O2 17.8 g·L = 1 and initial pH 3, whereas 44-19% removals were reached with the other cata...
Syngas production by bi-reforming methane on an Ni–K-promoted catalyst using hy...
Cunha, Adelino F.; Morales-Torres, Sergio; Pastrana-Martínez, Luisa M.; Martins, António A.; Mata, Teresa M.; Caetano, Nídia; Loureiro, José M.Steam reforming of methane (SRM) and dry reforming of methane (DRM) are frequently used in the production of syngas; however, the bi-reforming of methane (BRM) is an interesting and alternative process. In this study, BRM was studied over MgO, a layered double hydroxide (LDH) phase that was destroyed between 600 °C and 900 °C during the reaction. It showed good sorption capacity for CO2 at relatively low temper...
Enhanced biocatalytic sustainability of laccase by immobilization on functional...
Costa, João B.; Lima, Maria J.; Sampaio, Maria J.; Neves, Márcia C.; Faria, Joaquim L.; Morales-Torres, Sergio; Tavares, Ana P. M.; Silva, Cláudia G.Chemically functionalized multi-walled carbon nanotubes (CNTs) are used as carriers for laccase immobilization. In this work, CNTs were modified using different approaches with a combination of methods involving hydrothermal oxidation with nitric acid, treatment with 3-aminopropyltriethoxysilane, glutaraldehyde, N-ethyl-N-(3-(dimethylamino)-propyl) carbodiimide hydrochloride and N-hydroxysuccinimide. The enzyme...
Catalytic wet peroxide oxidation with modified carbon nanotubes
Martin-Martinez, Maria; Machado, Bruno; Serp, Philippe; Morales-Torres, Sergio; Silva, Adrián; Figueiredo, José; Faria, Joaquim; Gomes, HelderCatalytic wet peroxide oxidation (CWPO) uses H2O2 as a source of hydroxyl radicals (HO) for the oxidation of organic species. This process is regarded as a potential solution for the treatment of aqueous effluents containing recalcitrant and toxic organic pollutants, difficult to remove by conventional biological processes, mainly if present at high concentrations (1- 10 g L-1) [1]. In a recent study, three ma...
Role of nitrogen doping on the performance of carbon nanotube catalysts: a cata...
Martin-Martinez, Maria; Ribeiro, Rui; Machado, Bruno; Serp, Philippe; Morales-Torres, Sergio; Silva, Adrián; Figueiredo, José; Faria, JoaquimFour magnetic carbon nanotube samples (CNTs: undoped, completely N-doped and two selectively N-doped) have been synthesized by chemical vapor deposition. The materials were tested in the catalytic wet peroxide oxidation (CWPO) of highly concentrated 4 nitrophenol solutions (4-NP, 5 g L-1). Relatively mild operating conditions were considered (atmospheric pressure, T = 50 ºC, pH = 3), using a catalyst load of 2....
Carbon nanotubes as catalysts for wet peroxide oxidation: structure-reactivity ...
Ribeiro, Rui; Martin-Martinez, Maria; Machado, Bruno; Serp, Philippe; Morales-Torres, Sergio; Silva, Adrián; Figueiredo, José; Faria, JoaquimMagnetic neat and N-doped carbon nanotubes with different properties have been synthesized by chemical vapour deposiüon and tested in the catalytic wet peroxide oxidation of 4-nitrophenol solutions (5 g L') at relatively mild operating conditions (atmospheric pressure, T = 50 °C, pH = 3)~using a catalyst load = 2.5 g L-' and [H202]o = 17.8 g L-1. The results demonstrate that the catalyst hydrophobicity/ hydroph...