50 documents found, page 1 of 5
Catalytic Membranes for Water Pollution
Castanheiro, José; Cansado, Isabel; mourao, paulo; Lopes, Maria ElminaKnowledge of membrane reactors (MRs) has increased since the 1990s. Membrane reactors can combine the catalytic reaction with the separation step in a single unit. This technology can be applied in different processes, like the chemical and petrochemical industry, energy production, wastewater treatment and biotechnology. Membrane reactors have some advantages, such as the energy consumption is lower, and the v...
Removal of Microplastics and Nanoplastics From Water
Castanheiro, José; Cansado, Isabel; mourao, pauloOver the last few decades, plastics produced from fossil raw materials have been used for different applications. However, traditional plastics have environmental disadvantages. These plastics can be transformed through several processes, such as oxidation, photodegradation, and mechanical degradation. Microplastics (MPs) and nanoplastics (NPs) can be obtained from these processes. The MPs and NPs are present i...
Thermochemical Conversion Products for Solid Biofuels
Castanheiro, José; Cansado, Isabel; mourao, pauloDue to the environmental problems, which are associated with the increase of the emissions of gases with the greenhouse effect (CO2, SO2, and NOx), a climatic change, proven by the increase of the Earth Planet temperature, is observed. It is imperative to replace fossil sources, such as natural gas, coal, and petroleum, with renewable raw material for the production of biofuels. Biofuels can be solid, liquid, a...
Valorisation of Glycerol by Acetalization Reactions Using Heterogeneous Catalysts
Castanheiro, José; Cansado, Isabel; mourao, pauloThe production of biodiesel has increased considerably during the last few years. About 100 kg of glycerol is produced for every 900 kg of biodiesel formed. Glycerol is considered a byproduct, but it can be converted into new compounds with high commercial value, which leads to increased sustainability of the biodiesel industry. Different processes, such as esterification, etherification, and oxidation reaction...
Catalyst Materials for Polymer Electrolyte Membrane Fuel Cells: Design and Appl...
Castanheiro, José; Cansado, Isabel; Mourão, PauloDue to the increase of the emissions of CO2, SOX, and NOx, it becomes imperative to replace the traditional fossil fuels by “clean fuels”. The use of fuel cells can decrease the amount of gases with the greenhouse effect. There are several types of fuel cells, which can transform chemical energy into electric energy. The PEMFC is a polymer electrolyte membrane to fuel cells. These fuel cells can be operated bet...
Acetylation of 1,8-cineole with acetic anhydride over zeolites
Castanheiro, José; Cansado, Isabel; Mourão, PauloNeste trabalho foi realizado um estudo sobre a acetilação de 1,8-cineol com anidrido acético usando zeólitos como catalisadores. A reação foi realizada num reator descontínuo a 60º C. Os produtos da reação foram nonoacetotos e os diaacetatos, sendo também observado a formação de polímero (provavelmente oligómeros). Foram testados, como catalisadores, o zeólito beta, USY e ZSM-5. Os catalisadores foram caracteri...
METOXILAÇÃO DE TERPENOS COM CATALISADOR HETEROGÉNEO
Castanheiro, José; Cansado, Isabel; Mourão, Paulo; Mendes, joanaA metoxilação de terpenos (alfa-pineno, beta-pineno e limoneno) foi realizada num reator descontínuo a 60º C. Foi preparado um catalisador consistindo em poli(álcool vinílico) com um heteropoliácido (ácido tungstofosfórico) e reticulado com ácido sulfosuccínico, com o objectivo de introduzir grupos ácido sulfónico na matriz polimérica. Este catalisador (PW-PVA-SO3H) foi caracterizado por FTIR-ATR. Observou-se q...
Valorisation of plastic waste from the beverage industry through its transforma...
Nouira, Asma; Bekri-Abbes, Imene; Ezzeddine, Srasra; Cansado, Isabel; Mourão, PauloIn the present study, char and activated carbon (AC) materials were prepared from water bottles, recuperated from the waste collection point in Mourouj, Ben Arous, Tunisia, by using a rotative horizontal tubular furnace, on a lab/pilot scale and through chemicalandphysicalactivation. Different samples were characterized by N2 adsorption isotherms, SEM-EDX, XRD, EA as well as by the determinationofthepHzpc.Theef...
Biorrefinarias22
Castanheiro, José; Mourão, Paulo; Cansado, Isabel; Matos, Inês; Bernardo, MariaValorização de biorresíduos numa perspetiva da economia circular. Conversão de resíduos da biomassa em materiais adsorventes. Processos termoquímicos de conversão de biomassa em energia e outros compostos. Biorrefinarias: uma solução para o futuro?
Performance of Regenerated Activated Carbons on Pesticides Removal from the Aqu...
Cansado, Isabel; Mourão, Paulo Alexandre Mira; Castanheiro, José Eduardo dos Santos; Castanheiro, JoséAdsorbents presenting high adsorption capacity, fast adsorption rate, easy regeneration, and a good possibility for reusability are ideal for removing 4-chloro-2-methyl-phenoxyacetic acid (MCPA) or other pesticides from wastewater. Here, the effects of regeneration treatments on adsorption– desorption cycles are examined using two commercial activated carbons (ACs) (Merck and Norit 1240 X). MCPA adsorption was ...