SYNTHESIS AND CHARACTERIZATION OF CHITOSAN/SODIUM ALGINATE BLEND MEMBRANE FOR APPLICATION IN AN ELECTROCHEMICAL CAPACITOR

In this work, we report a stepwise formation method of a chitosan/sodium alginate polyelectrolyte complex (CS/SA PEC) membrane. The proposed method aiming at the utilization of the ultrasonic treatment of chitosan and sodium alginate solution allowed us to obtain a highly homogeneous hybrid membrane for electrochemical usage. The CS/SA PEC membrane saturated in a 2 M Li2SO4 aqueous solution was used in electrochemical double layer capacitor (EDLC) cell to study its applicability as quasi-solid electrolyte. Electrochemical characteristic of EDLC cells was determined by electrochemical impedance spectroscopy, cyclic voltammetry and galvanostatic charge/discharge methods. The results show that the EDLC cell with CS/SA PEC quasi-solid electrolyte exhibit a comparable specific capacitance (102 F g-1 for 0–0.8 V) to CS reference (100 F g-1 for 0–0.8 V) and commercial separator (99 F g-1 for 0–0.8 V) cells. Thus, the CS/SA PEC membrane can be considered as an alternative modification for chitosanbased materials of electrochemical purpose.

Electrochemical Approach for Isolation of Chitin from the Skeleton of the Black Coral Cirrhipathes sp. (Antipatharia)

The development of novel and effective methods for the isolation of chitin, which remains one of the fundamental aminopolysaccharides within skeletal structures of diverse marine invertebrates, is still relevant. In contrast to numerous studies on chitin extraction from crustaceans, mollusks and sponges, there are only a few reports concerning its isolation from corals, and especially black corals (Antipatharia). In this work, we report the stepwise isolation and identification of chitin from Cirrhipathes sp. (Antipatharia, Antipathidae) for the first time. The proposed method, aiming at the extraction of the chitinous scaffold from the skeleton of black coral species, combined a well-known chemical treatment with in situ electrolysis, using a concentrated Na₂SO₄ aqueous solution as the electrolyte. This novel method allows the isolation of α-chitin in the form of a microporous membrane-like material. Moreover, the extracted chitinous scaffold, with a well-preserved, unique pore distribution, has been extracted in an astoundingly short time (12 h) compared to the earlier reported attempts at chitin isolation from Antipatharia corals.