In the past, the mass fraction of zinc oxide in plasticizer A was calculated by using the amount of EDTA consumed by pirelli chemical method manual titration.
More than 10 kinds of reagents need to be added during the experiment, and if the pH value is not adjusted well, the end point will not change significantly, so it is difficult to grasp the accurate end point, resulting in a large error in the test results.
Therefore, atomic absorption spectrometry was used.
The comparison results between manual titration and atomic absorption spectrometry are introduced as follows.
Preparation of basic zinc carbonate
The mass fraction of zinc oxide determined by manual titration (10 times) was 0.123,0.132, 0.124,0.127, 0.130,0.126,0.122,0.125,0.134,0.126, respectively.
The arithmetic mean deviation was 0.003;
Standard deviation is 0.0039;
The confidence interval was (12.7 0.3) %.
The mass fraction of zno determined by aas was 0.132,0.129, 0.127, 0.130, 0.130, 0.128,0.131,0.129, 0.130, 0.128, respectively.
The arithmetic mean deviation was 0.001;
Standard deviation is 0.0016;
The confidence interval was (12.9 0.1) %.
The mass fraction index of zinc oxide in plasticizer A is 0.12 -- 0.15. As can be seen from the above comparison results, the determination by atomic absorption analyzer is completely feasible, which not only simplifies the operation steps of manual titration method, but also saves time and improves accuracy and accuracy, and can replace manual titration method.