Improved hydrogen determination in petroleum streams using a bench top pulsed NMR analyzer

An improved methodology using an inexpensive bench top pulsed NMR instrument has been developed for measuring hydrogen contents of a broad range of hydrocarbon process streams. This new methodology expands the range of samples which can be routinely analyzed for hydrogen to include all materials that are liquids at ≤60 °C. Both weight-normalized and density-normalized approaches are described and have precisions on the order of 0.05 wt %. The density-normalized technique enables precision measurement of hydrogen contents in total liquid product samples from pilot units that have light ends and contain waxy solids at room temperature. This is a significant advantage in accurately determining hydrogen consumption for a large number of refinery processes. The density-normalized technique has an advantage in sample handling but requires a density measurement at the temperature of the NMR measurements.