Optimization and improvement of the jolt-phosphate method for determination of free silica in dust
The improved method used a digital ceramic heating plate for precise temperature control during the sample digestion process.A small electronic stirrer was used to take the place of manual continuous and uniform mixing of the heated sample.After digestion,the sample was cooled to 100℃,and the dilution and acid washing steps were combined by directly adding approximately 0.1mol/L hydrochloric acid at around 60℃to 100-150mL of the sample,followed by immediate filtration.The improved method and the national standard method were used to measure quality control samples and actual samples,and the results showed a relative deviation of less than 8%between the two methods.The precision of the improved method was less than 5%,which was better than the national standard.The improved method is convenient to operate,and provides a more efficient method for daily sample detection with reliable and highly precise results.
NETL
NSTL
万方数据
维普
