Analysis of Hydrocarbons Using PCI-GC-MS

Introduction

Interest in hydrocarbon-producing microalgae is growing in the field of renewable energy development. Since the hydrocarbons produced by microalgae contain no oxygen and are similar in properties to heavy oil, they can be a convenient substitution for existing liquid fuels, and it is advantageous that an energy resource do not compete with food production. Research is being performed into obtaining petrochemical raw material from the hydrocarbons produced by microalgae, and mass spectrometry is used in identification of these products. Gas chromatography-mass spectrometry (GC-MS) normally uses electron ionization (EI) to produce ions for analysis, but when using this EI method for hydrocarbon analysis, the larger the carbon number the more difficult it becomes to confirm the molecular ions on a mass spectrum. The ion-molecule reactions that occur with positive chemical ionization (PCI), however, tend to produce protonated molecules and dehydride molecules, from which information about molecular mass is easier to obtain compared to the EI method. In this article, we describe a case example of using PCI- GC-MS to measure hydrocarbons obtained from the catalytic decomposition of squalane, a compound obtained from microalgae.

October 30, 2015 GMT