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The influence of macromolecular additives on the mechanical properties of polyethersulfone (PES) and polysulfone (PS) is investigated. Ultrafiltration membrane sheets are prepared from PES and PSF based polymers via liquid non-solvent induced phase separation (NIPS), and employing polyvinylpyrrolidone (PVP), polyethylene glycol (PEG) and Pluronic®(PLU) co-polymers as macromolecular additives. The impact of additives on the main membranes’ characteristics are studied; i.e., pure water permeability, membrane porosity, morphology and surface chemistry. The main mechanical properties are examined for all membranes and are correlated to the chemical composition of the membranes. Overall, the membranes prepared using PLU showed a superior tensile strength compared to other membrane samples, while PVP was found to enhance the membrane formation by suppressing microvoids formation. This study provides a better understanding of the main mechanical and other characteristics of membrane materials with regards to using additives.

Artichoke peels were used to produce activated carbon using chemical activation methods. Two activation protocols were compared: a two-step method A and a one-step method B. As newly used activating agents, KCl, CrCl3and TiCl4were compared. The results show that method B is superior to A. KOH with method B had an area of 2321m2/g and a total pore volume 1.0071cm3/g, of which 0.9794cm3/g was confined to micropores. The corresponding values for KCl are 1731, 0.6925 and 0.6718. TiCl4had lower but comparable values with those of KCl. CrCl3appeared to be the least successful among the three newly used activating agents. The post-activation washing step strongly affects the characteristics of the final product. The differences among the effects of Zn, Cr and Ti are discussed in terms of the differences in polarizing power.