Cadmium Removal from Giant Squid ( Dosidicus gigas ) Hydrolysate in Fixed-Bed Columns Packed with Iminodiacetic Resin: Tools for Scaling up the Process

Giant squid hydrolysate (GSH) elaborated from different batches from a fishing company was evaluated for cadmium removal. Fixed-bed column packed with iminodiacetic resin as adsorbent was used. GSH solution at different cadmium concentrations were fed in the fixed-bed column and breakthrough curves were evaluated. A high degree of metal removal from the solution was achieved and the saturation point (C e /C 0 ≤ 0.8) was achieved more quickly at higher concentrations of cadmium. The maximum capacity of adsorption (q 0 ) was obtained using the Thomas model, where 1137.4, 860.4, 557.4, and 203.1 mg g −1 were achieved using GSH with concentrations of 48.37, 20.97, 12.13, and 3.26 mg L −1 , respectively. Five cycles of desorption of the resin with HCl (1 M) backflow and regeneration with NaOH (0.5 M) were also evaluated, where no significant differences ( p -value > 0.05) were observed between each cycle, with an average of 935.9 mg g −1 of q max . The in-series columns evaluated reached a total efficiency of 90% on average after the third column in GSH with a cadmium concentration of 20.97 mg L −1 . This kind of configuration should be considered the best alternative for cadmium removal from GSH. Additionally, the chemical composition of GSH, which was considered a quality parameter, was not affected by cadmium adsorption.