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Formation of petroleum organic deposits on steel surfaces

An adhered organic deposit, formed within the petroleum well on the steel surface of the tubing walls, was systematically characterized following a sequence of bulk and surface techniques. The results allowed the identification of the tubing wall and its internal surface structures. As a consequence of the contact with sulphur‐bearing compounds such as H2S and brine from petroleum, the pre‐oxidized steel surface was modified by non‐stoichiometric iron compound formation. These new iron phases favour adsorption and chemisorption of the petroleum polar compounds on the steel surface. Copyright © 2002 John Wiley & Sons, Ltd.