Abstract: The reaction product of thiourea (alternatively, a primary amine), formaldehyde, and an aromatic ketone (e.g. acetophenone) in the presence of an organic acid (e.g. acetic acid) and a mineral acid has been found effective as a corrosion inhibitor base for metals in acid media, particularly fluids containing halogen acids. The corrosion inhibitor base can be prepared in nearly 100% yield, and is a more effective base, as contrasted with bases prepared with fatty acids as contrasted with lower molecular weight organic acids such acetic acid.

Abstract: The reaction of propargyl alcohol and iodine gives 2,3di-iodo-2-propen-1-ol, and it has been discovered that this compound is effective as an intermediate in a corrosion inhibitor for metals in acid media, particularly halogen acids. The compound provides iodine to the media in a stable form that does not appear to degrade over time.

Abstract: An acid soluble mercury metal salt intensifier is provided to inhibit corrosion in conjunction with a corrosion inhibitor when a steel surface is present in an acid environment. The mercury metal salt may be a mercuric halide, such as mercuric chloride or may be a mercuric acetate, mercuric oxide, mercuric nitrate or mixtures of all of these. An acid soluble copper metal salt, such as cuprous halide, for example, cuprous chloride, copper acetate, cupric formate, cuprous nitrate and mixtures thereof, may also be present as a co-intensifier. In one application, the mercuric salt intensifier is used in a fluid for treatment of a subterranean well for the acid enhancement of production within the well by introduction of the fluid through a high alloy steel conduit positioned within the well. Methods of inhibiting acidic corrosion when steel surfaces are in an acid environment, particularly steel surfaces containing chrome, and methods of treating a subterranean well for enhanced production are also presented.

Abstract: An acid soluble copper metal salt intensifier is provided for a fluid for treatment of a subterranean well for enhancement of production within the well by introduction of the fluid through a high alloy steel member positioned within the well. The treatment fluid comprises an acidic injection medium and an acid corrosion inhibitor. The intensifier is introduced into the fluid for deposition on or effective treatment contact with the high alloy steel. A method of inhibiting acidic corrosion and a method of treating a subterranean well for enhanced production also are disclosed.