Identification of a Novel Ester Obtained during Isolation of C80 (“ARN”) Tetraprotic Acids from an Oilfield Pipeline Deposit
journal contributionposted on 16.12.2015, 17:42 by P. A. Sutton, B. E. Smith, D. Waters, S. J. Rowland
Solid deposits in some oilfield pipelines and oil-processing equipment include calcium salts of C80−82 polycyclic tetracarboxylic acids (“ARN” acids) probably originating from Archaea. It is thought that such deposits form once calcium in seawater comes into contact with crude oils containing the acids, under relevant conditions. The deposits may cause restriction or blockage of pipelines and equipment, with considerable consequent costs for downtime and cleaning. The accurate measurement of the concentrations of the acids in oils is an important requirement for the development of mathematical models for the prediction of the formation of oilfield deposits. We have now identified, in a deposit from one North Sea oilfield pipeline, in addition to the known C80−82 polycyclic tetracarboxylic acids, a hitherto unreported ester of C80 (“ARN”) acids. We report the evidence for the identification and suggest reasons for the occurrence of the ester. Quantitative analyses which exclude determination of such esters may underestimate the potential for oils to cause flow problems. Calculations for computer models based on such data might then be in error.