Effect of the adsorption of Cu2+, Cd2+ in food analysis container

There is an error in analysis of trace metal content in the food beacuse of adsorption characteristics in container of metal ions, to understand and grasp the source of error is an important way to avoid and reduce the analysis error.The behavior of adsorption of Cu～ (2+) , Cd～ (2+) on the inner wall of glass and plastic vessels in solutions of different acidity, content and temperature was studied by AAS.It was showed that the higher acidity, higher content and lower temperature could reduce adsorption of metal irons.Adsorption law of Cu～ (2+) , Cd～ (2+) in the glass and plastic were significantly different.The adsorption process on the glass conforms to the first order kinetic model, and on the plastic conforms to the secondary order kinetic model.The rate of adsorption in the glass vessel was larger than that in the plastic vessel.