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Activated carbons (ACs) were prepared from recycled polyethylene terephthalate (PET) by chemical activation with KOH and used successfully for the removal of 4-chloro-2-methylphenoxyacetic acid (MCPA) and Methylene Blue (MB) from aqueous media. In order to improve the adsorption capacity towards pollutant removal, the AC was submitted to different post-treatments. After oxidation, the sample exhibited an increase in MB adsorption capacity but showed a decreased MCPA adsorption removal extent. High-temperature treatment was not favourable for increasing the MB or MCPA adsorption capacity. However, after treatment with sodium hydroxide or urea, the samples showed a significant increase in their MCPA adsorption capacities. Normalisation of the MB and MCPA adsorption data with respect to the micropore volume led to a clearer understanding of the influence of the textural and chemical characteristics of the AC on the removal of MB and MCPA. The MB and MCPA adsorption isotherms were analysed via the Langmuir and Freundlich models, with the calculated parameters accurately fitting the experimental data and exhibiting good agreement between them.

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The synthesis of inorganic nanostructured materials for the consolidation of stone and wall paintings is reviewed. To begin, a description of the methods most commonly used to prepare nanoconsolidants is provided, particularly in the frame of colloid chemistry. Some concepts of the carbonation mechanism as well as the transport properties of some of these materials are addressed. An overview of the synthesis methods together with some of the application particularities of the distinct consolidants are presented thereafter. Furthermore, the requisites for efficient consolidants and some drawbacks of the nanoconsolidants are discussed.

We study the in vitro adsorption of fluoxetine hydrochloride by different adsorbents in simulated gastric and intestinal fluid, pH 1.2 and 7.5, respectively. The tested materials were two commercial activated carbons, carbomix and maxsorb MSC30, one activated carbon fibre produced in our laboratory and also three MCM--41 samples, also produced by us. Selected samples were modified by liquid phase oxidation and thermal treatment in order to change the surface chemistry without significant modifications to the porous characteristics. The fluoxetine adsorption follows the Langmuir model. The calculated Q0 values range from 54 to 1112 mg/g. A different adsorption mechanism was found for the adsorption of fluoxetine in activated carbon fibres and activated carbons. In the first case the most relevant factors are the molecular sieving effect and the dispersive interactions whereas in the activated carbons the mechanism seams to be based on the electrostatic interactions between the fluoxetine molecules and the charged carbon surface. Despite the different behaviours most of the materials tested have potential for treating potential fluoxetine intoxications.