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Updated: May 3, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
The chemistry of tetrameric acids in petroleum
Johan Sjöblom1, Sébastien Simon1, Zhenghe Xu2
1Ugelstad Laboratory, Norwegian University of Science and Technology, 7491 Trondheim, Norway.
Abstract:
This article reviews the properties of a novel class of molecules: the tetrameric acids. These molecules have brought a large interest in petroleum science since the discovery of the family of molecules named ARN in 2004. ARN, which is naturally present in oil, is responsible, by reaction with calcium ion, of the formation of calcium naphthenate deposits; organic deposits that cause irregularities in crude oil production and processing. In order to study the properties of ARN, a model tetrameric acid molecule mimicking some of its properties named BP-10 has been developed in 2008 by Nordgård and Sjöblom and has been extensively used since then. After presenting the experimental techniques used to study the tetrameric acids, this review describes in detail the structure, preparation, detection and the bulk and interfacial properties of tetrameric acids ARN and BP-10. Finally the prediction of the operational problems with calcium naphthenate precipitation in new fields is discussed.
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