Analysis of Saturated Hydrocarbons by Redox Reaction with Negative-Ion Electrospray Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Xibin Zhou, Quan Shi, Yahe Zhang, Suoqi Zhao,^* Rui Zhang, Keng H. Chung, and Chunming Xu*

State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 China 

Well Resources Inc., 3919-149A Street, Edmonton, Alberta, Canada T6R 1J8

^*Corresponding Author: E-mail: sqzhao@cup.edu.cn; xcm@cup.edu.cn

DOI: 10.1021/ac203035k

Keywords: Alcohols; Fossil Fuels; Hydrocarbons; Ionization; Ions

Abstract: A novel technique was developed for character ization of saturated hydrocarbons. Linear alkanes were selectively oxidized to ketones by ruthenium ion catalyzed oxidation (RICO). Branched and cyclic alkanes were oxidized to alcohols and ketones. The ketones were then reduced to alcohols by lithium aluminum hydride (LiAlH₄). The monohydric alcohols (O₁) in the products obtained from the RICO and RICO-LiAlH4 reduction reactions were charac terized using negative-ion electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) for identification of iso-paraffins, acyclic paraffins and cyclic paraffins. Various model saturated compounds were used to determine the RICO reaction and ionization selectivity. The results from the FT-ICR MS analysis on the petroleum distillates derived saturated fraction were in agreement with those from field ionization gas chromatography time-of-flight mass spectrometry (FI GC-TOF MS) analysis. The technique was also used to characterize a petroleum vacuum residue (VR) derived saturates. The results showed that the saturated molecules in the VR contained up to 11 cyclic rings, and the maximum carbon number was up to 92.