Research Of Removing Heavy Mental In Squid Liver

Cadmium and copper ions were removed from the squid(Illes argentines) liver homogenates with the ions exchange resin. Styrene macroporous strong acid cation exchange resin(D072) was selected, as indicated by cadmium and copper ions dsorption efficiency. A new ions exchange resin adsorption apparatus was produced to be the experimental set-up. Effects of resin amount, material-water ratio, time, p H and temperature were discussed on the adsorption efficiency. The experimental data were fitted separately with Langmuir isotherm model, Freundlich isotherm model, Pseudo-first-order adsorption kinetic and Pseudo-second-order adsorption kinetic. The main contents and results are as follows:1. The cadmium and copper contents in the fresh squid liver were determined by graphite furnace atomic absorption spectrophotometer. The results showed that cadmium and copper contents were 59.6±0.07 mg/kg and 68.2±0.11 mg/kg, which seriously exceeded the national standards. The basic ingredients were measured with national standard method. The contents of crude protein and crude fat were 16.43±0.51 % and 27.38±0.14 %. Analysis of amino acids was by high performance liquid chromatography, which showed high contents of aspartic acid, glutamic acid, lysine, leucine, histidine, etc.2. A new plug-in ions exchange resin adsorption experiment set-up was developed. The adsorption of cadmium and copper ions by styrene macroporous strong acid cation exchange resin(D072) was more efficient. Experimental results indicated that: cadmium and copper ions adsorption efficiency were increasing with time, when the time of 210 min, the adsorption reached equilibrium state; Adsorption efficiency achieved a better state of the homogenates p H 3.0; Adsorption efficiency raised when the resin amount increased; With the material-water ratio 1:10 went up to 3:10, the adsorption efficiency first increased and then decreased; In the temperature range(25 ℃ <T <50 ℃), the higher temperature is conducive to ions exchange reaction. Adsorption efficiency of cadmium and copper ions were 94.34 % and 82.97 % when the homogenates p H 3.0, proportion of resin and the homogenates of 20.0 g/L, material-water ratio of 1:5.3. Adsorption process was studyed respectively with thermodynamics and kinetics. Langmuir isotherm model, Freundlich isotherm model, Pseudo-first-order adsorption kinetic and Pseudo-second-order adsorption kinetic were adopted to fit experimental data separately. The study suggested that Langmuir isotherm model and Pseudo-second-order adsorption kinetic more accurately reflected the D072 resin for the exchange adsorption process of cadmium and copper ions.