Methods of preparing liquid blends for building calibration curves for the effect of concentration on laser-induced fluorescence intensity

摘要

Disclosed herein are methods for determining and replicate unknown ratios of original target liquid blends, such as hydrocarbon fuel blends or contaminants, by using an in-process fluorescence-monitored procedure. The methods rely on trial-and-error mixing of the fuel ingredients into a single container. At the end of the trial-and-error procedure, the formed blend becomes an exact replica of the target fuel blend. The methods can also be used to build calibration curves without employing sets of previously prepared standard solutions.

主权项

1. A method of identifying and replicating unknown ratios of an original target fuel blend, the method comprising steps of:
placing a liquid handling device in a 90° or a front-surface excitation-emission geometry with respect to a light source and a fluorescence detector unit based on a type of the original target fuel blend in use; measuring a first laser-induced fluorescence spectrum of the original target fuel blend to obtain a target spectrum; storing and displaying the target spectrum on a background of a personal computer using spectroscopy software; dispensing pre-calculated amounts of fuel ingredients relative to a total amount of volume present in a vessel to produce consecutive fuel blends of desired ratios in the vessel; measuring a second laser-induced fluorescence spectrum for each of the consecutive fuel blends to produce blend spectrums; and building calibration curves of laser-induced fluorescence intensity versus fuel blend concentration based on the blend spectrums and the dispensed pre-calculated amounts of the fuel ingredients for identifying and replicating the unknown ratios of the original target fuel blend.