Home – Home – Jornals – Chemistry for Sustainable Development 2023 number 4

The validation of a standard certified method for measuring the mass fraction of oil products in soils and bottom sediments by IR spectrometry for measuring the content of oil products in sorbent samples based on ash and slag waste from thermal power engineering, and changes in the method of sample preparation in order to improve the metrological characteristics of the method are proposed. To calculate the metrological characteristics of the method to be validated, 48 measurements were carried out according to the recommendations set out in RMG 61-2010 (Appendix E). The assessment of the repeatability index was carried out according to the Cochran criterion. Grubbs statistics were used to evaluate the intralaboratory precision index. The correctness score was determined using a two-sample Student's t -test. The assessment of the accuracy indicator was performed by the selective relative standard deviation of the measurement results of the control sample. Quality indicators of the standard methodology PND F 16.1:2.2.22-98 (2005 edition): repeatability rate 8 %; index of intralaboratory precision 10 %; correctness score 15 %; accuracy rate 25 %. Quality indicators of the method being validated: repeatability rate 2.7 %; index of intralaboratory precision 2.7 %; correctness score 1.3 %; accuracy rate 5.3 %. The measurement results obtained using the developed validated method for measuring the oil product content in the samples of modified sorbent based on ash and slag wastes are more reproducible in terms of repeatability and precision, as well as more correct and accurate in comparison with the results obtained when measuring using the standard PND F method 16.1:2.2.22-98 (2005 edition).