32 documents found, page 1 of 4

Sort by Issue Date

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, Nuno

ABSTRACT: 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...

Date: 2025   |   Origin: Repositório do LNEG

Opportunities and Constraints of the Adsorption of Rare Earth Elements onto Pyr...

Nogueira, Miguel; Bernardo, Maria; Ventura, Márcia; Matos, Inês; Pinto, Filomena; Lapa, Nuno

ABSTRACT: 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...

Date: 2024   |   Origin: Repositório do LNEG

Microalgae as a selenium vehicle for nutrition: a review

Pires, Rita; Costa, Margarida; Pereira, Hugo; Cardoso, Helena; Ferreira, Luís; Lapa, Nuno; Silva, Joana; Ventura, Márcia

Selenium (Se) is essential for human and animal nutrition, playing a key role in antioxidant and immune functions. Organic Se is better for supplementation because it is more efficiently assimilated and less toxic than its inorganic form. Due to the scarcity of Se in European soils, supplementation in feed and food is necessary. Currently, inorganic Se (sodium selenite and selenate) and organic Se in Se-enriche...


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 do

ABSTRACT: 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 ...

Date: 2023   |   Origin: Repositório do LNEG

Advantages of structural inspection and diagnosis for traditional buildings’ re...

Silva, Renata; Surra, Elena; Quelhas, Bruno; Costa, Alexandre A.; Lapa, Nuno; Delerue-Matos, Cristina

This work demonstrated, through Life Cycle Assessment (LCA), the environmental advantages brought by the application of the Structural Inspection and Diagnosis (SID) methodology to the structural refurbishment of 7 traditional buildings located in the city of Porto (Portugal), when compared to the common total demolition and reconstruction approach. The early diagnosis of the conservation state of the existing ...


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...


BioH2 from Dark Fermentation of OFMSW: Effect of the Hydraulic Retention Time a...

Martins, Inês; Surra, Elena; Ventura, Márcia; Lapa, Nuno

Food wastes represent one third of all food produced worldwide. It is crucial to both prevent the production of food waste and recover the wasted fraction with the aim to valorizing it. In this context, the conversion of the organic fraction of municipal solid wastes (OFMSW) into bioH2 by dark fermentation (DF) is an important technology to valorize these wastes into renewable fuel. Nevertheless, the DF of OFMS...


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, Nuno

ABSTRACT: 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...

Date: 2021   |   Origin: Repositório do LNEG

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, Nuno

ABSTRACT: 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...

Date: 2021   |   Origin: Repositório do LNEG

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, Svitlana

ABSTRACT: 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 ...

Date: 2021   |   Origin: Repositório do LNEG

32 Results

Queried text

Refine Results

Author





















Date














Document Type



Funding



Access rights



Resource





Subject