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[Volume chemistry-ultraviolet spectrum differential method for determining the oxygen content in anti-corrosion copper powder with surface film consisting of benzotriazole]. | LitMetric

A method for determining the oxygen content in anti-corrosion copper powder with benzotriazole inhibitor surface film was established and the ultraviolet spectra of benzotriazole under various conditions were studied. The maximum absorption was at lamdamax=273 nm, and the temperature did not influence the absorption intensity at normal temperature. The linear range of concentration was 0-2.2 microg x mL(-1), the detection limit was 0.02 microg x mL(-1), and the apparent molar absorptivity of benzotriazole was epsilon = 5.41 x 10(4) L x mol(-1) x cm(-1) at 273 nm. Because the anti-corrosion copper powder consisted of copper metal, copper oxide and benzotriazole protecting film, the Cu and BTA contents of the powder were determined through EDTA titration and ultraviolet spectrophotometry, respectively, after the samples were decomposed with HCl and H2O2, and the oxygen content of the powder was calculated by differential method. The instruments are simple, the method is economical, and the manipulation is convenient. The standard deviation is 1.7%, and the differentiation coefficient is 7.6%. In conjunction with the application of the national standard method, the oxygen contents before and after the formation of the protecting film of the electrolyte copper powder were comparatively analyzed with satisfactory results.

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