Surface active reagents were generally used in aqueous-based stimulation fluids to lower the interfacial tension that restricts fluid flow in the rock matrix.

Oil film around formation fines sets a barrier for acids or other stimulation fluids to react with formation rock. Mutual solvent mixed in acids or stimulation fluids will dissolve the oil films and water-wet the formation fines.

Ferric and ferrous ions remain in acid solutions during acidizing operations due to the very low pH of acids. When acid travels from surface to formation, it will dissolve iron from equipment, tubulars, scales and iron minerals in the formation. While spending the acid, the pH of the acid will go up, and can result in the precipitation of iron. Trivalent Iron (Ferric) precipitates at about pH 3, while the divalent Iron (Ferrous) will not precipitate until the acid spent to a pH of 8. To minimize the precipitation of iron, it is better to keep the iron in the ferrous iron. It is therefore required to add an iron stabilizer (reducer) into acid systems.

Destructive reactions between metals and acids cause serious corrosion problems in acidizing operations. Corrosion inhibitors are generally required in acids to minimize these destructive reactions without introducing adverse effect on reactions between acids and formations. For high temperature or chemically aggressive environment, inhibitor aid is also required to prevent tubulars and downhole tools from strong acid corrosion and pitting.

Emulsions have adverse effects on production of oil and gas if they are formed at either reservoir, wellbore or surface facility. Demulsifiers or non-emulsifying agents are generally utilized to break or prevent the emulsions and recover the oil & gas production.
Some crude oils react with acid to form a black asphaltic sludge to plug of pore spaces and may be responsible for the poor performance of matrix treatments in some reservoirs. Anti-sludging agents are therefore utilized to avoid the acid sludges.

Multi-phase treatment fluids such as emulsions, dispersions or foams are sometimes more beneficial than single phase fluids regarding specific application conditions. The emulsifiers, dispersants, or foaming agents are playing crucial roles in preparation of these multi-phase fluids and ensure their superior technical performance.

Inorganic scales, organic scales, scales mixtures and H2S are detrimental to well performance. Scale dissolvers, inhibitors and H2S scavengers are therefore used in oilfield chemical treatment to eliminate or prevent the adverse effects of scales and H2S on oil or gas well performance.

In-situ gelled acids or other diverting agents are the most-commonly used treatment techniques in carbonate acidizing or acid fracturing. Gelling agents, crosslinkers and diverting agents are playing crucial roles in preparation of these treatment fluids.

Clay stabilizers or inhibitors are chemicals used to prevent swelling or dispersive clays presented in the oil or gas formations.
The friction loss while pumping treatment fluids through the wellbore can be reduced significantly by utilization of friction reducers.

Acids, non-acids such as chelating agents, and base oils are generally used in oilfield services to prepare various treatment fluid systems in sandstone acidizing, carbonate acidizing or acid fracturing, and wellbore cleanup.