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A systematic review of sustainable gold extraction from raw ores using alternat...
Sousa, Rui; Regufe, Maria João; Fiúza, António; Machado Leite, Mário; Futuro, AuroraABSTRACT: Drawing on recent experimental and commercial developments, this review reappraises potential substitute leach reagents for cyanide in the gold mining sector. In addition to extraction, the application of these reagents in the gold processing, pre-treatment and gold purification stages is explored. The main objective here is to discuss how the gold extraction process can be more sustainable, with a vi...
Tailings microbial community profile and prediction of its functionality in bas...
Chung, Ana Paula; Coimbra, Carina; Farias, Pedro; Francisco, Romeu; Branco, Rita; Simão, Francisco V.; Gomes, Elsa; Pereira, Alcides J. S. C.In a circular economy concept, where more than 300 million tons of mining and quarrying wastes are produced annually, those are valuable resources, supplying metals that are extracted today by other processes, if innovative methods and processes for efficient extraction of these elements are applied. This work aims to assess microbiological and chemical spatial distribution within two tailing basins from a tung...
Nanosized iron based permeable reactive barriers for nitrate removal – Systemat...
Araújo, Rui; Meira Castro, Ana C.; Santos Baptista, João; Fiúza, AntónioIt is unquestionable that an effective decision concerning the usage of a certain environmental clean-up technology should be conveniently supported. Significant amount of scientific work focussing on the reduction of nitrate concentration in drinking water by both metallic iron and nanomaterials and their usage in permeable reactive barriers has been worldwide published over the last two decades. This work aim...
The use of nanoparticles in soil and water remediation processes
Araújo, Rui; Meira Castro, Ana C.; Fiúza, AntónioEnvironmental nanoremediation of various contaminants has been reported in several recent studies. In this paper, the state of the art on the use of nanoparticles in soil and groundwater remediation processes is presented. There is a substantive body of evidence on the growing and successful application of nanoremediation for a diversity of soil and groundwater contamination contexts, particularly, for heavy me...
Nanosized iron based permeable reactive barriers for nitrate removal - Systemat...
Araújo, Rui; Meira Castro, Ana C.; Santos Baptista, João; Fiúza, AntónioIt is unquestionable that an effective decision concerning the usage of a certain environmental clean-up technology should be conveniently supported. Significant amount of scientific work focussing on the reduction of nitrate concentration in drinking water by both metallic iron and nanomaterials and their usage in permeable reactive barriers has been worldwide published over the last two decades. This work aim...
Re-use assessment of thermoset composite wastes as aggregate and filler replace...
C. S. Ribeiro, Maria; Meira Castro, Ana C.; Silva, Francisco; Santos, Jorge M.; Meixedo, Joao Paulo; Fiúza, António; Dinis, M. L.; Alvim, Mário RuiGlass fibre-reinforced plastics (GFRP), nowadays commonly used in the construction, transportation and automobile sectors, have been considered inherently difficult to recycle due to both the cross-linked nature of thermoset resins, which cannot be remoulded, and the complex composition of the composite itself, which includes glass fibres, polymer matrix and different types of inorganic fillers. Hence, to date,...
A case study undertaken recycling & reuse of glass fiber reinforced thermoset p...
Ribeiro, M.C.; Fiúza, António; Meira Castro, Ana C.; Silva, F.G.; Meixedo, JP; Dinis, M.L.Glass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: crosslinked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequent...
An experimental study on recycling and reuse of pultruded composite material wa...
Ribeiro, M.C.S; Meira Castro, Ana C.; Silva, F.; Fiúza, AntónioGlass fibre-reinforced plastics (GFRP) have been considered inherently difficult to recycle due to both: cross-linked nature of thermoset resins, which cannot be remoulded, and complex composition of the composite itself. Presently, most of the GFRP waste is landfilled leading to negative environmental impacts and supplementary added costs. With an increasing awareness of environmental matters and the subsequen...
An integrated recycling approach for GFRP pultrusion wastes: recycling and reus...
Meira Castro, Ana C.; Carvalho, João P.; Ribeiro, M. C. S.; Meixedo, João Paulo; Silva, Francisco J. G.; Fiúza, António; Dinis, M. L.In this study, efforts were made in order to put forward an integrated recycling approach for the thermoset based glass fibre reinforced polymer (GPRP) rejects derived from the pultrusion manufacturing industry. Both the recycling process and the development of a new cost-effective end-use application for the recyclates were considered. For this purpose, i) among the several available recycling techniques for t...
The influence of coal-fired power plants operations on environmental radioactiv...
Dinis, Maria de Lurdes; Fiúza, António; Góis, Joaquim; Carvalho, José S. de; Meira Castro, Ana C.The natural radioactivity of coal and by-products from coal-fired power plants has been reported in many countries. Most of these studies focus on the radioactivity levels of airborne discharges with enhanced concentration in fly ashes. However, the distribution of natural radionuclides in the environment is crucial to estimate the radiological impact and the resulting risk to the potential exposed nearby popul...