Online Measurement of Sodium Nitrite Based on Near-Infrared Spectroscopy

In this study, a method was developed for the rapid online measurement of sodium nitrite solutions using near-infrared spectroscopy. A series of standard solutions of sodium nitrite at different concentrations were prepared, and the samples were measured in cuvettes and flow cells. Following the preprocessing of raw spectra and band selection, partial least squares were used to establish a prediction model, and the coefficient of determination (R2) of the validation set and the root mean square error of prediction (RMSEP) of the model were 0.9989 and 0.0338. The results demonstrate that the established model can meet the demands of online measurement and perform the rapid, nondestructive detection of sodium nitrite solutions, which provides some basis for the automated formulation of feedstock in spent fuel reprocessing.