Viktor Kochkodan

Characterization and Separation Performance of a Novel Polyethersulfone Membrane Blended with Acacia Gum

Novel polyethersulfone (PES) membranes blended with 0.1–3.0 wt. % of Acacia gum (AG) as a pore-former and antifouling agent were fabricated using phase inversion technique. The effect of AG on the pore-size, porosity, surface morphology, surface charge, hydrophilicity, and mechanical properties of PES/AG membranes was studied by scanning electron microscopy (SEM), Raman spectroscopy, contact angle and zeta potential measurements. The antifouling -properties of PES/AG membranes were evaluated using Escherichia coli bacteria and bovine serum albumine (BSA). The use of AG as an additive to PES membranes was found to increase the surface charge, hydrophilicity (by 20%), porosity (by 77%) and permeate flux (by about 130%). Moreover, PES/AG membranes demonstrated higher antifouling and tensile stress (by 31%) when compared to pure PES membranes. It was shown that the prepared PES/AG membranes efficiently removed lead ions from aqueous solutions. Both the sieving mechanism of the membrane and chelation of lead with AG macromolecules incorporated in the membrane matrix contributed to lead removal. The obtained results indicated that AG can be used as a novel pore-former, hydrophilizing and antifouling agent, as well as an enhancer to the mechanical and rejection properties of the PES membranes.

Mixed Adsorption of Cetyltrimethylammonium Bromide and Triton X-100 Surfactants on Carbon Black

Adsorption of cationic cetyltrimethylammonium bromide (CTAB) and nonionic Triton X100 surfactants from their mixed aqueous solutions on graphitized carbon black (CB) have been studied. The adsorption isotherms of CTAB or Triton X100 from single solutions on CB surface shown to be of the Langmuir type. In the mixed solutions of CTAB and Triton X100 surfactants, the adsorption of CTAB or Triton X100 on CB decreased in the presence of the other surfactant due to competitive adsorption of the components. It was shown that the mole fraction of Triton X-100 on CB surface has been essentialy changed depending on total concentration of the surfactants mixture. At mixture concentration corresponding to the unsaturated monolayer, a strong synergetic effect was found when the surface excess concentration Triton X100 at the CB surface in the presence of CTAB is higher than that for Triton X-100 in the absence of CTAB.