Naphthenic acids (NAs) are complex mixtures of carboxylic acids that are responsible for the corrosivity of the crude oil with high total acid number(TAN).NAs are difficult to analyze due to their complexity and the l...Naphthenic acids (NAs) are complex mixtures of carboxylic acids that are responsible for the corrosivity of the crude oil with high total acid number(TAN).NAs are difficult to analyze due to their complexity and the lack of commercially available NA standards.This paper describes the use of negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) for the analysis of NAs in Liaohe heavy crude oil.FT-ICR MS resolves thousands of species in a single mass spectrum allowing for unambiguous determination of elemental composition.O2 classes (with two O heteroatoms in one molecule) and their carbon number (revealing the extent of alkylation) distribution were detailedly investigated.We find that 2-5 rings NAs is the dominate component of acidic compounds in Liaohe crude oil,espasically with a high abundance of steroid acids and hopanoic acids.Neg-ESI-FTMS is very well suited to the characterization of naphthenic acids within a crude oil sample.Determination of the nature of the naphthenic acids present provides vital information,such as the acids’ sizes and composition.展开更多
文摘Naphthenic acids (NAs) are complex mixtures of carboxylic acids that are responsible for the corrosivity of the crude oil with high total acid number(TAN).NAs are difficult to analyze due to their complexity and the lack of commercially available NA standards.This paper describes the use of negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR MS) for the analysis of NAs in Liaohe heavy crude oil.FT-ICR MS resolves thousands of species in a single mass spectrum allowing for unambiguous determination of elemental composition.O2 classes (with two O heteroatoms in one molecule) and their carbon number (revealing the extent of alkylation) distribution were detailedly investigated.We find that 2-5 rings NAs is the dominate component of acidic compounds in Liaohe crude oil,espasically with a high abundance of steroid acids and hopanoic acids.Neg-ESI-FTMS is very well suited to the characterization of naphthenic acids within a crude oil sample.Determination of the nature of the naphthenic acids present provides vital information,such as the acids’ sizes and composition.
