Thiocarbohydrazide‐modified chitosan as anticorrosion and metal ion adsorbent

To explore the application of chitosan (CS) derivatives in anticorrosion and adsorption, thiocarbohydrazide‐modified chitosan (TCHECS) derivative was synthesized and characterized. The preliminary electrochemical measurements of the behaviors of 304 steel and Cu sheets in 2% HAc (v/v) containing TCHECS, chitosan (CS), and hydrazine cross‐linked epoxy‐N‐phthaloylchitosan (HECS) had been performed. The short‐term electrochemical tests show that the new compound can act as a mixed‐type metal anticorrosion inhibitor; its inhibition efficiency is 88% when the concentration was 30 mg/L. The preliminary adsorption studies for sorbents TCHECS and HECS on a metal ion mixture aqueous solution were also performed. The results show that TCHECS can absorb As (V), Ni (II), Cu (II), Cd (II), and Pb (II) efficiently at pH 9; the removal of the As (V), Ni (II), Cu (II), Cd (II), and Pb (II) are around 55.6–99.9%.