Abstract: Corrosion in aqueous alkanolamine, physical solvents, or combination of alkanolamine and physical solvent solutions used to remove acid gases from natural gas, synthetic gas, or light hydrocarbon streams can be reduced by addition of mixtures of oxygen scavengers or mixtures of oxygen scavengers and sodium molybdate. The oxygen scavengers must be promoted to reduce metal surfaces in contact with the solutions to a more passive, harder, and insoluble form at the operating temperature of the treating system. The sodium molybdate provides additional passivation especially in the imperfections on the surface of the metal where corrosion accelerates.

Abstract: The invention relates to flowable and pumpable multicomponent mixtures based on a multiphase mixture of water and oil containing emulsifiers and, if desired, other soluble, emulsifiable and/or dispersible auxiliaries for their use in exploration by drilling and/or for the further treatment of the wells thus drilled. The invention is characterized by the use of emulsifiers or emulsifier systems which, in the particular multicomponent mixture in question, lead to temperature-controlled phase inversion at a phase inversion temperature (PIT) in a temperature range of which the upper limit is so far below the working temperature of the multicomponent mixture in geological exploration that the water-based part of the multicomponent mixture is present as a disperse (invert) phase in the continuous oil phase (w/o invert emulsion) while the lower limit of this temperature range enables the multicomponent mixture to be converted into an o/w emulsion with a continuous aqueous phase.

Abstract: In the removal of particulates from a wellbore, such as in air drilling for hydrocarbon recovery, a mixture of an amphoteric foaming agent and, typically, an anionic surfactant is employed. An aqueous solution thereof having a pH of at least 9.5 is used to generate a foam for removing the particulates; then the foam is collapsed by the introduction of acid to reduce the pH below about 4, the particles are removed mechanically, the pH is restored to greater than 9.5, and the foaming solution is returned to the wellbore. The solution may be used several times; partial losses of foaming agent in the process may be easily replenished with each cycle. Cationic surfactants may be used instead of anionic, with foaming and foam collapse being controlled at opposite pH's. Savings are realized in water, drilling chemicals, and settling pits and the like for removing particulates from the foam.

Abstract: The present invention provides a method of treating a subterranean formation by rapidly viscosifying a normally liquid hydrocarbon. The method is accomplished by admixing (i) an alkyl orthophosphate acid ester and (ii) an alkali metal hydroxide present in an amount sufficient to at least partially neutralize said ester and (iii) a reaction product resulting from the reaction of a source of aluminum or ferric ions with a C.sub.8 -C.sub.18 surface active amine solubilized in the presence of an organic solvent such as a C.sub.2 -C.sub.4 monohydric alcohol with the normally liquid hydrocarbon. The mixture rapidly viscosifies to a level sufficient to transport proppant and then can be introduced into a subterranean formation to treat the formation in a desired manner.