25 documents found, page 1 of 3
Adsorption of the inhalation anaesthetic isoflurane by activated carbon fibres ...
Ribeiro Carrott, M.; Carrott, P.J.M.; Correia, P.F.M.M.Activated carbon fibres with a range of pore sizes, prepared from pre-oxidized acrylic fibre by physical activation in carbon dioxide at different temperatures and times, were investigated as adsorbents for the inhalation anaesthetic isoflurane (2-chloro-2-(difluoromethoxy)-1,1,1-trifluoroethane). Adsorption-desorption isotherms of isoflurane were determined at 293 K and were analysed by the alpha-S method usin...
Evolution of porosity of activated carbon fibres prepared from pre-oxidized acr...
Carrott, P.J.M.; Ribeiro Carrott, M.M.L.; Correia, P.F.M.M.Industrially pre-oxidized acrylic fibres were used to prepare activated carbon fibres (ACF). The results obtained show that pre-oxidation was effective in increasing the carbon yield during carbonization and reducing the reactivity of the char with CO2 during activation, making it possible to obtain ACF with high pore volumes, up to 1.15 cm3 g−1, with BET area of 2064m2 g−1, even without a prior laboratory stab...
Utilização de Sais de Lítio em Misturas Ternárias de Sais Fundidos
Guerreiro, L.; Henriquez, M.; Carrott, P.J.M.; Carrott, M.M.L.R.; Collares Pereira, M.A Energia Solar é um recurso abundante e pode ser captada através de diversas formas: fotovoltaica, térmica de baixa temperatura, térmica de alta temperatura. Os sistemas de centrais termosolares com armazenamento de energia com sais fundidos têm ganho quota de mercado em diversas latitudes (Espanha, Marrocos, Africa do Sul, Chile, EUA, etc) sendo que cada vez mais se estuda a utilização de sais fundidos não só...
Stability of clay-based catalysts in contact with water vapour
Cansado, I.P.P; Carrott, M. M. L. R.; Carrott, P.J.M.; Castilho, P.; Catrinescu, C.; Fernandes, C.; Breen, C.The search for cleaner processes is one of the major challenges in modern chemical industries. In this context clay derived materials are environmentally friendly catalysts that can be easily tailored to optimize their catalytic activity for a precise reaction of interest. Furthermore, clay-based catalysts can be easily separated, recovered and reused and their versatility, low cost, high catalytic activity and...
Using Different Co-Adjuvant Activating Agents to Improve Activated Carbon Adsor...
Cansado, I.P.P; Mourão, P.A.M.; Ribeiro Carrott, M.M.L.; Carrott, P.J.M.Activated carbon (AC) has proved to be an effective adsorbent for the removal of an assortment of organic and inorganic pollutants from aqueous or gaseous media. However, the pursuit for more effective and cheaper AC is still very active and a diversity of textural and chemical treatments are described as a way to expand their applications. It is well known that the surface area and surface chemistry of AC stro...
Carbon aerogels used in carbon dioxide capture
Marques, L.M.; Carrott, P.J.M.; Ribeiro Carrott, M.M.L.In this work the maximum carbon dioxide adsorption capacity of carbon aerogels, obtained by a sol-gel process using 2,4-dihydroxybenzoic acid/formaldehyde (DHBAF) and resorcinol/formaldehyde (RF) as precursors, was studied. The effect of increasing the temperature of carbonization and physical activation of the samples DHBAF was also studied. The results showed that the maximum adsorption capacity is favoured a...
Porosity in ion-exchanged and acid activated clays evaluated using n-nonane pre...
Ribeiro Carrott, M.M.L.; Cansado, I.P.P.; Carrott, P.J.M.; Russo, P.A.; Castilho, P.; Fernandes, C.; Catrinescu, C.; Breen, C.The applicability of the n-nonane pre-adsorption method for characterising the porosity in clays is presented. Na-SD, a Naþ-exchanged purified bentonite, and materials obtained by Al3þ-exchange and acid treatments of Na-SD and SAz-1 were used. Nitrogen adsorption isotherms, at 196 C, were determined before and after n-nonane pre-adsorption on each of the samples. In all materials, n-nonane remained adsorbed in ...
Adsorption of MCPA on different activated carbons
Mourão, P.A.M.; Cansado, I.P. P.; Ribeiro Carrott, M.M.L.; Carrott, P.J.M.Pesticides play an important role in the success of modern farming and food production but their use increases the residue levels in soils and waters and has been a public concern because of the potential risk to human health and the environment. Pesticides are generally applied in larger amounts than those needed for the pest control and they are swept away by transport processes such as leaching. Liquid phase...
Using different AC to improve MCPA removal from liquid phase
Cansado, I.P.P.; Mourão, P.A.M.; Ribeiro Carrott, M.M.L.; Carrott, P.J.M.The work presented here focuses on the adsorption of MCPA on a series of ACs prepared from recycled PET or cork via different activation methods. All ACs were characterised by nitrogen adsorption at 77 K and by elemental analysis. The adsorption isotherms of MCPA were determined on selected ACs, where the same amount of AC was added to flasks containing equal volumes of aqueous solutions with different initial ...
Catalisadores derivados de uma argila do Porto Santo: efeito da ativação ácida ...
Ribeiro Carrott, M.M.L.; Cansado, I.P.P.; Russo, P.A.; Carrott, P.J.M.; Catrinescu, C.; Castilho, P.; Fernandes, C.; Breen, C.No âmbito de um projeto de investigação em curso (PTDC/CTM-CER/121295/2010), materiais derivados de argilas, de várias proveniências e submetidas a diferentes tratamentos de modificação, estão a ser usados como catalisadores em várias reações de interesse, como, por exemplo, na metoxilação do limoneno e na conversão do glicerol. Uma das possíveis vantagens, face a outros catalisadores alternativos, relaciona-se...