Reactive absorption and solubilities of isobutylene in the aqueous solutions of alkylbenzenesulfonic acids with different chain lengths

Abstract

In the aqueous solutions of p-toluenesulfonic acid, ethylbenzenesulfonic acid, dodecylbenzenesulfonic acid, and sulfuric acid, the solubilities of isobutylene were determined by the volumetric method at . Following the pseudobinary complexation model, the activities of isobutylene were determined for all acids, based on the Wilson model incorporated with the chemical theory. In solubilizing isobutylene, the significant increase of the equilibrium constant K, and the chemical conversion to tert-butyl alcohol suggested that the chemical complexation of isobutylene with acids might play a key role in the mechanism of the solubilization. By increasing the chain length of alkylbenzenesulfonic acids, it is also found that the efficiencies of acids in solubilizing isobutylene were enhanced at lower concentrations, but significantly reduced at higher concentrations. After a transition concentration where there appeared minima, the efficiencies of acids were greatly enhanced, indicating that the chemical conversion to t-butyl alcohol istriggered by acids. Further, the solubilizing efficiencies of mixed acids consisting of p-toluenseulfonic acid and dodecylbenzenesulfonic acid, linearly decreased depending on the effective chain length at a fixed molar concentration of acids, and it may be attributed to the formation of complex by acid rather than to the incorporation of isobutylene into the micelles.