Synthesis and Characterization of Chitosan-Based Schiff Base and Cu(II) Complex from Shrimp Shells and its Application on Catalysis and Bio-sorption

In recent years, metal complexes and biopolymers have gained significant attention in environmental applications such as catalysis and heavy metal removal. Chitosan, a biopolymer derived from chitin, is well-known for its biodegradability, non-toxicity, and strong metal ion affinity, which can be further enhanced through Schiff bases to improve its catalytic and adsorption capabilities. The primary objectives of this study were to investigate whether Cu(II) complex of Chitosan Salicylaldehyde Schiff Base CSSB-Cu(II) can act as an efficient catalyst in hydrogen peroxide decomposition reaction and to find out the raw absorbent which has the highest Cadmium ion removal efficiency from among the absorbents Chitin (CT), Chitosan (CS) and Chitosan Salicylaldehyde Schiff Base (CSSB). CSSB was synthesized using the Schiff condensation reaction between the amino group of CS and the carbonyl compound of salicylaldehyde with the elimination of water molecules and it was complexed with Cu(II) ion to produce CSSB-Cu(II) complex. The catalytic effect of the CSSB-Cu(II) complex on the kinetics of the decomposition of hydrogen peroxide was investigated and compared with CSSB. CSSB-Cu(II) showed a better catalytic effect than CSSB and has a pseudo-first-order catalytic decomposition for H2 O2 . CT, CS, and CSSB were investigated as adsorbents for the Cd(II) removal to determine their cadmium removal efficiencies. This study concludes that the removal efficiency of CSSB was greater than that of CS and CT. The equilibrium data agreed more with the Langmuir model than with the Freundlich model. The IR and electronic spectral data confirm the presence of an imine bond and the existence of the complex in square planar geometry.