A novel cellulose acetate-polyoxometalate (PW11Fe(H2O)O39) hybrid membranes: preparation, characterization and study of their potential for humic acid adsorption

The design of membranes was generally achieved using biopolymers, synthestic polymers, or thin film composites. Membranes have been extensively used for industrial process and were mainly applied for the elimination of various pollutants. In this investigation, cellulose acetate-PW 11 Fe(H 2 O)O 39 membranes were prepared by a phase inversion method through dispersing PW 11 Fe(H 2 O)O 39 particles in cellulose acetate casting solution at different compositions (4%, 8%, and 15%). The prepared hybrid membranes were analysed using FT-IR spectroscopy and scanning electron microscope (SEM). FT-IR spectra exhibited the characteristic absorption bands of cellulose acetate and polyoxometalate. The cross-sectional images indicated that the addition of a high amount (15%) of PW 11 Fe(H 2 O)O 39 to cellulose acetate matrix improved the porosity. The incorporation of PW 11 Fe(H 2 O)O 39 in the cellulose matrix was proved by the decrease of the contact angle values from 59.14 to 37.61°. The addition of PW 11 Fe(H 2 O)O 39 improved the water content. For instance, it achieved 69.66% for cellulose acetate-PW 11 Fe(H 2 O)O 39 (15%). The porosity increased from 15 to 74% for the original cellulose acetate membrane and cellulose acetate-PW 11 Fe(H 2 O)O 39 (15%), respectively. The pure water flux increased with the addition of PW 11 Fe(H 2 O)O 39 to cellulose acetate matrix. The retention of humic acid was more appropriate in acidic medium, it attained its maximum at 500 mg/L and it decreased with the increase of NaCl concentration.