Study Of The Quick Analysis Method Of Cd～(2+), Cu～(2+), Pb～(2+) And NO₃～- In Wheat Flour

Microwave is a mature technology use in the digestion of the sample. Microwave-assisted is a new separate technology. Microve digestion has some merits, such as rapid speed, little reagent, low pollution, and so on. The traditional pretreatment method has some defects, such as fussy opetation, long time.In this article, NanYang color wheat is used as the sample, the appliance microwave is used as the digestion and extraction instrument,microwave digestion is the method in the determination of Cd²⁺,Cu²⁺,Pb²⁺in color wheat. We researched the influence of the microwave conditions on the digestion effect, such as acid system, the digestion power, digestion time and the acid quantity, and so on. The research indicates, in the system of HNO₃-H₂SO₄,HNO₃-HClO₄ and HNO₃-HClO₄-H₂SO₄, the third system has the best digestion effect. The sample is 1.0g(precision 0.0001), in the condition of the best complete digestion, the quantity of the mixed acid is 9.00ml, the time is from 35min to 40min, the solution is pellucid, achromatous after digestion. The concentration of Cd²⁺,Cu²⁺, Pb²⁺ are apart determinated by the PXSJ-216 ion analysis instrument. In the determination of Cd²⁺, the lowest limit is 2.056×10^-4mg·L^-1, the linear range is 0.015mg·L^-1～100.0mg·L^-1, RSD is 1.7% ～4.8%, the recovery efficiency is 85.0 %～101.0%.In the determination of Cu²⁺, the lowest limit that can be detected is 1.025×10^-4mg·L^-1, the linear range is 0.032mg·L^-1～65mg·L^-1, RSD is 1.1%～3.1...