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Submitted by Isabel Melo (imelo@sa.isel.pt) on 2020-02-13T12:28:34Z No. of bitstreams: 1 Effective_PLAlmeida.pdf: 2814345 bytes, checksum: 6bf343b065cf3469082d8961791ea3bf (MD5) Made available in DSpace on 2020-02-13T12:28:34Z (GMT). No. of bitstreams: 1 Effective_PLAlmeida.pdf: 2814345 bytes, checksum: 6bf343b065cf3469082d8961791ea3bf (MD5) Previous issue date: 2019-10-09 info:eu-repo/semantics/publishedVersion

Submitted by Fátima Piedade (fpiedade@sa.isel.pt) on 2013-01-31T13:10:47Z No. of bitstreams: 1 Copper Bis(oxazoline) Encapsulated in Zeolites and Its Application as Heterogeneous Catalysts for theCyclopropanation of Styrene.rep.pdf: 205434 bytes, checksum: 6110e7fd9837e3b3f2f03b7b9b8b6da4 (MD5) Made available in DSpace on 2013-01-31T13:10:47Z (GMT). No. of bitstreams: 1 Copper Bis(oxazoline) Encapsulated in Zeolites and Its Application as Heterogeneous Catalysts for theCyclopropanation of Styrene.rep.pdf: 205434 bytes, checksum: 6110e7fd9837e3b3f2f03b7b9b8b6da4 (MD5) Previous issue date: 2011-10-19

Micropore size distributions of various carbonaceous materials were obtained using two methods based on the Dubinin−Radushkevich equation and the relationship between the characteristic parameter of this equation and the pore width. One method was the well-known Dubinin−Radushkevich−Stoeckli (DRS) equation, and the other method used the integral adsorption equation without assuming a mathematical distribution for dw0/dE0. These methods were applied to carbon dioxide adsorption data on four activated carbons and eight chars to obtain micropore size distributions. Significant differences were found between the results obtained by the two methods. The DRS method gives an average of the distribution obtained by the method using the integral adsorption equation, because the latter is not constrained to a particular preassumed shape. The results reveal that the differences are more significant for the analysis of adsorption data on chars than on activated carbons. This was attributed to the fact that a less-hom...

The potentialities of cork powder waste as raw material for the preparation of activated carbons that can be used in the control of atmospheric pollution was studied. Three series of activated carbons were prepared by chemical activation of cork powder waste using KOH as activating agent. In each series, the ratio between the amount of the cork powder and the activating agent was changed, and the effect of the activating temperature was studied also. It was possible to obtain activated carbons with specific surface areas higher than 1300 m2/g and microporous volumes higher than 0.5 cm3/g. Regarding the surface chemistry properties, a set of carbons with pH at the point of zero charge ranging from 9.0 to 5.6, was obtained. The properties of adsorption of various noxious volatile organic compounds (VOCs) were investigated, and the sample activated with the highest amount of KOH, and at the highest activation temperature, showed promising properties in both the abatement and the selective adsorption of VOCs.