Abstract: The present invention relates to the field of laboratory-scale sample preparation, which describes a methodology for the specific isolation of tetraprotic naphthenic acids, called ARN acids, from residual naphthenate deposits from petroleum production. The method consists of cleaning the naphthenate deposit, converting the naphthenate salts to naphthenic acids and isolating the ARN acids from the other organic acids, using a silica-based sorbent material with aminopropyl functional groups, previously selected for an efficient elution of different functional groups and polarities.

Abstract: Naphthenate deposition is formed from tetraprotic naphthenic acids having aliphatic chains and high molecular weight, provided with four carboxylic terminations, sometimes called ARN acids. Obtaining these species from their matrix of origin requires the prior use of sample preparation methods aiming at an efficient extraction of naphthenic acids. Obtaining ARN acids from naphthenate deposits is advantageous in the potential for reusing waste and reducing environmental damage. The process also adds value to waste materials from the oil production and exploration process. The present invention relates to the field of laboratory-scale sample preparation, which describes a methodology for the specific isolation of tetraprotic naphthenic acids, called ARN acids, from residual naphthenate deposits from petroleum production.