Determination of titanium dioxide in cement by Microwave Digestion-VIS Spectrophotometry

A new method to determine titanium dioxide in cement by Microwave Digestion-DAPM VIS Spectrophotometry which has many advantages such as simple operation, safe and fast, dissolve completely is presented in this paper. The determination conditions and working parameters of the microwave digestion instrument including the species and dosage of digestion reagent, wavelength, reaction time and the dosage of DAPM were optimized. The results show that samples were dissolved by HNO3-HF-H2O2, 395nm as the wavelength and 12mL of DAPM. The method has been validated by determination of titanium dioxide in national standard reference materials of GBW03201, GBW03201c, GBW03207 and GBW03205. The results were in agreement with certified values and the RSD was 1.07%-4.52%. The recovery ratio was ranging from 91.8% to 108.0% and the ｜△lgC｜was less than 0.018. Comparison with the traditional digestion method that analytical cement samples of Sichuan, there is no significant difference between the two methods by Student's t test. This new method provide a new way for quick and accurate to determine the content of titanium dioxide in cement.