23 documents found, page 1 of 3
Recovery of Nd3+ and Dy3+ from E-Waste Using Adsorbents from Spent Tyre Rubbers...
Nogueira, Miguel; Matos, Inês; Bernardo, Maria; Pinto, Filomena; Fonseca, Isabel Maria; Lapa, NunoABSTRACT: This paper investigates the use of spent tyre rubber as a precursor for synthesising adsorbents to recover rare earth elements. Through pyrolysis and CO2 activation, tyre rubber is converted into porous carbonaceous materials with surface properties suited for rare earth element adsorption. The study also examines the efficiency of leaching rare earth elements from NdFeB magnets using optimised acid l...
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?
Opportunities and Constraints of the Adsorption of Rare Earth Elements onto Pyr...
Nogueira, Miguel; Bernardo, Maria; Ventura, Márcia; Matos, Inês; Pinto, Filomena; Lapa, NunoABSTRACT: Rare earth elements (REEs), comprising seventeen metallic elements, including lanthanides, scandium, and yttrium, are indispensable for modern technological industries due to their unique properties. However, their supply is critically risky for the European Union, with 95% of global production concentrated in China, Brazil, Vietnam, Russia, India, and Australia. This mini-review examines the adsorpti...
Valorisation of spent tire rubber as carbon adsorbents for Pb(II) and W(VI) in ...
Bernardo, Maria; Lapa, Nuno; Pinto, Filomena; Nogueira, Miguel; Matos, Inês; Ventura, Márcia; Ferraria, Ana Maria; Rego, Ana Maria Botelho doABSTRACT: Spent tire rubber-derived chars and their corresponding H3PO4 and CO2-activated chars were used as adsorbents in the recovery of Pb(II) ion and (W(VI)) oxyanion from synthetic solutions. The developed chars (both raw and activated) were thoroughly characterized to have insight about their textural and surface chemistry properties. H3PO4-activated chars presented lower surface areas than the raw chars ...
Evaluation of activated carbons produced from Maize Cob Waste for adsorption-ba...
Surra, Elena; Ribeiro, Rui P.P.L.; Santos, Tiago; Bernardo, Maria; Mota, José P.B.; Lapa, Nuno; Esteves, Isabel A.A.C.Two activated carbons (AC) resulting from CO2 activation of Maize Cob Waste (MCW) were investigated as adsorbent materials for biogas upgrading to bio-methane applying a biorefinery concept. The porous carbons were originated from different times of activation and the one resulting from 3 h with CO2 (MCW(PA)3 h) showed better textural properties, higher working capacity, and selectivity towards CO2 than the car...
Cr(III) dynamic removal in a fixed-bed column by using a co-gasification char
Dias, Diogo; Bernardo, Maria; Pinto, Filomena; Fonseca, Isabel Maria; Lapa, NunoABSTRACT: A char (GC) obtained from the co-gasification of rice husk and polyethylene was used in a fixed-bed column with continuous flow for Cr(III) removal assays from synthetic and industrial wastewaters. For comparison purposes, a commercial activated carbon (CAC) was also used. The best experimental conditions in the continuous removal assays were the following ones: Cr(III) inflow concentration = 5 mg L-1...
Cr(III) dynamic removal in a fixed-bed column by using a co-gasification char
Dias, Diogo; Bernardo, Maria; Pinto, Filomena; Fonseca, Isabel Maria; Lapa, NunoABSTRACT: A char (GC) obtained from the co-gasification of rice husk and polyethylene was used in a fixed-bed column with continuous flow for Cr(III) removal assays from synthetic and industrial wastewaters. For comparison purposes, a commercial activated carbon (CAC) was also used. The best experimental conditions in the continuous removal assays were the following ones: Cr(III) inflow concentration = 5 mg L-1...
Highly efficient porous carbons for the removal of W(VI) oxyanion from wastewaters
Dias, Diogo; Don, Davide; Jandosov, Jakpar; Bernardo, Maria; Pinto, Filomena; Fonseca, Isabel Maria; Sanches, André; Caetano, P. S.; Lyubchyk, SvitlanaABSTRACT: Pyrolysis chars derived from rice wastes were chemically activated and used in W(VI) oxyanion adsorption assays in synthetic and mining wastewaters. For comparison purposes, a commercial activated carbon (CAC) was also used. Different experimental conditions were tested in the adsorption assays: solid/liquid ratio (S/L), initial pH, contact time, and initial W concentration. The porous carbon P2C+KOH ...
A Model to Evaluate de Value of the Information Delivered by e-Government
Monteiro, José Augusto; Bernardo, Maria; Rocha, TâniaNeste artigo apresenta-se um modelo para avaliação da informação entregue através dos sítios Web de governo eletrónico. Através deste modelo propõe-se capturar o contributo do utilizador do governo eletrónico como um ativo para melhorar a qualidade da sua interação com a administração pública através da Web. A concetualização do modelo tem como principais pilares os domínios da acessibilidade, usabilidade, expe...
Um Modelo de Valor de Entrega de Informação aplicado ao Governo Eletrónico
Monteiro, José Augusto; Bernardo, Maria; Rocha, TâniaNeste artigo apresenta-se um modelo para avaliação da informação entregue através dos sítios Web de governo eletrónico. Através deste modelo propõe-se capturar o contributo do utilizador do governo eletrónico como um ativo para melhorar a qualidade da sua interação com a administração pública através da Web. A concetualização do modelo tem como principais pilares os domínios da acessibilidade, usabilidade, expe...