Abstract: Based on the NIR results and the group composition data by SH/T 0606 standard method of 383 FCC diesel and hydrotreated diesel samples, a NIR hybrid analysis model was established using partial least squares (PLS) method. Verification results indicate that the results predicted by model are very close to the standard method and the repeatability even better. It was applied in a refinery LTAG process. The continuous analysis of the compositions of feedstock before and after hydrotreating for 15 days proves the practicability of this rapid analysis method.

Key words: LTAG, LCO hydrotreating, NIR, partial least squares