GB877845A - Gasoline fuels for internal combustion engines - Google Patents

Abstract

Alkenyl succinamic acids, having 10-25 carbon atoms in the alkenyl radical, and suitable for use in gasoline compositions (see Group III), may be prepared by reacting the appropriate alkenyl succinic acid anhydride in a 1 : 1 molar ratio with ammonia or with ammonium hydroxide. Thus, ammonia gas may be bubbled through a solution of the anhydride in a hydrocarbon solvent, such as benzene, toluene or xylene, preferably at about 60-80 DEG C. Alternatively, ammonium hydroxide solution may be added to the anhydride (preferably in the presence of an organic solvent such as petroleum ether, benzene xylene or toluene) at about 5-30 DEG C., and the ammonium succinamate thus formed may be converted to the free acid by the addition of a dilute aqueous acid such as hydrochloric or sulphuric acid. In Examples, (1) tetrapropenyl succinamic acid is formed by reaction between ammonium hydroxide and tetrapropenyl succinic anhydride, with subsequent addition of hydrochloric acid and (2) 11-tricosenyl succinamic acid is formed by reaction between ammonia gas and 11-tricosenyl succinic anhydride.ALSO:The formation of ice in the carburetter of an internal combustion engine is inhibited by adding to the gasoline fuel a small amount of an alkenyl succinamic acid having 10-25 carbon atoms in its alkenyl radicle. The gasoline fuel may also contain anti-knock agents, pre-ignition inhibitors, anti-rust agents, metal deactivators, dyes, antioxidants, detergents and solvent oils. Examples of solvent oils are mineral oils, diester oils, polyalkylene glycols, silicones, phosphate esters, polypropylenes and polybutylenes. In examples, 0.01, 0.02 or 0.05% by weight of tetrapropenyl succinomic acid is added to a gasoline composition consisting of catalytically cracked gasoline, natural gasoline, benzene, toluene and butane.