Catalytic chelation technique for the removal of heavy metal from Clarius batrachus (C. batrachus)

[Display omitted] •According to Malaysia Food Regulations (MFR), the level of heavy metal in food that is safe to be consumed for Pb, Cd, Ni, and Cu is below 1 μg/g.•The optimum treatment condition was achieved using 400 ppm TCD for three hours treatment time at temperature of 32.50 ± 0.50 °C.•The optimized conditions of trisodium citrate with the eggshell catalyst gave the removal percentage of 90 %, 84 %,72 % and 100 % for Cu, Cd, Pb and Ni, respectively.•All the metals have been removed below the MFR except for Pb metal where the highest removal is only 72.02 % (3.64 μg/g). The excessive occurrence of heavy metal has become a matter of concern for the health of aquatic ecosystem. Copper (Cu), Cadmium (Cd), Lead (Pb) and Nickel (Ni) are the most common heavy metal pollutants. Clarius batrachus is a fish that widely consumed by the society and it can be contaminated with heavy metal due to increasing in domestic and industrial activities. Trisodium citrate dihydrate (TCD) and chicken eggshell catalyst was developed and introduced as a new couple of chelating agents for heavy metal in Clarius batrachus species. The synthesized catalyst was characterized by X-ray Diffractometer (XRD), Fourier Transform InfraRed (FTIR), Scanning Electron Microscopy (SEM) and Nitrogen Adsorption (NA) to study the phase structure and morphologies of the sample. Different types and concentration of TCD chelating agents, times and temperatures were studied to find out the optimum condition to treat the C. batrachus species. The optimum treatment condition was achieved using 400 ppm TCD for three hours treatment time at temperature of 32.50 ± 0.50 °C. The optimized conditions of trisodium citrate with the catalyst gave the removal percentage of 90 %, 84 %,72 % and 100 % for Cu, Cd, Pb and Ni, respectively.