Catalytic chelating technique on lead, nickel and cadmium removal from Fenneropenaeus merguiensis

Abstract

Fenneropenaeus merguiensis is one of the main sources of protein in Malaysian dietary. The heavy metals content (0.8495, 0.4923 and 0.0854 ug/g for lead, nickel and cadmium respectively) in F. merguiensis were below permissible limit of Malaysia Food Regulations (1985) and EU Food Regulations. However, as the pollution increased at tremendous rate, continuing uptake of food containing heavy metals may affect human health. In this study, chelation and catalytic chelation techniques were applied to remove Pb, Ni and Cd in F. merguiensis. The heavy metals analyses were performed using flame atomic absorption spectroscopy (FAAS). The chelation technique was carried out at three different parameters; chelating agent dosage, treatment time and treatment temperature. Three chelating agents used were trisodium citrate, disodium oxalate and sodium acetate. The study revealed that the optimum conditions of chelation technique were at 29.5°C, 2 hours treatment time and 600 mg/L of trisodium citrate. Percentage of removal of Pb, Ni and Cd were 71.51%, 42.82% and 44.85% respectively. The introduction of CaO/Al2O3 and MgO/Al2O3 catalysts had enhanced the removal capacity of the heavy metals in F. merguiensis. The catalytic chelation technique was conducted at optimum condition of chelation technique but the treatment time was changed to 1 hour, to maintain the freshness of F. merguiensis. The percentage of removal of Pb and Cd was higher when CaO/Al2O3 was used with percentage removal were 90.23% and 94.95% respectively, while the percentage of removal of Ni was 59.09% when MgO/Al2O3 was used as catalyst. Percentage of Pb removal obtained from Central Composite Design (CCD) is in good agreement with experimental result, which pvalue (<0.0001) indicated that, the percentage of Pb removal is statistically significant.