Objective To improve the determination of free silica content in dust by pyrophosphoric acid heated by silicon carbide in order to ensure the accuracy of detection. Methods Analyze the influencing factors and controls during the experimental process, including the determination of dust sample composition, sample processing, preparation of pyrophosphate, control of heating temperature, hot filtration, ashing and weighing. Results By controlling and improving the influencing factors during the experimental process, measurement errors can be effectively avoided. Conclusion The importance of determining the characteristics of dust samples during the measurement process lies not only in the preparation of pyrophosphate and strict temperature control, but also in the accuracy of data analysis for quality control sample analysis.

silicon carbide  /  constant temperature heating  /  dust  /  free silicon dioxide  /  pyrophosphate method