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Improvement of membrane properties is an important issue to enhance the efficiency of water permeation processes. Nanocomposite membranes are gaining prominence in this field due to the particular properties of these materials. In the present study, incorporating titanate nanowires (TNW) into the cellulose acetate (CA) matrix allowed getting a nanocomposite membrane with modified characteristics. Morphologic and physical–chemical properties of the synthesized membranes were characterized by Fourier transform infrared spectrometry and scanning electron microscopy analysis, presenting a dense, uniform membrane formation with a highly dispersed inorganic phase when low amounts of particles were added. The membranes were tested by measuring water flux and salt rejection. The results showed that the incorporation of inorganic nanostructures into polymer membranes affects their transport properties. It was observed an increase of three times in water flux, reaching from 1.33 to 4.0 L/h m2, with NaCl rejection over 65%. Membranes with such characteristics could be specially designed for nanofiltration or forward osmosis processes as a promising application for water desalination or energy generation. [ABSTRACT FROM AUTHOR]

Optimization of the purification process remains a challenge in the production of proteins for pharmaceutical or industrial applications. In this context, the purpose of this work was to study the adsorption of myoglobin onto hydroxyapatite (HAp) modified with metal ions (Cu2+, Ni2+, Zn2+), with the aim of its purification from a complex medium. The influence of pH and ionic strength on the adsorption process was evaluated using experimental design methodology. Experiments for determining the kinetics and adsorption isotherms were undertaken, allowing the determination of important equilibrium parameters required for scale-up. High adsorption capacities (ca. 90 mg myoglobin/g modified HAp) and rapid adsorption kinetics were observed. These results indicate the applicability of HAp as a support for pseudo-affinity chromatography. [ABSTRACT FROM AUTHOR]