Micellization And Application Of Super-Concentrated Hydrochloric Acid

Acid catalysis plays an important role in industrial synthesis. Because of the traditional liquid acid have a series of problems, solid acids and super-acids have been extensively used since the acidity of them is much stronger than that of conventional mineral acids. However, they lose the catalytic activities easily when water is involved. Therefore, many acid-catalyzed reactions are still carried out by using conventional acids, e.g., HC1 and H2SO4. In order to resolve the problem of solubility of volatile acids are limited, this thesis utilized amphiphilic-based reversed micelle system to improve the solubility of HC1 in water and prepared super-concentrated hydrochloric acid (SC-HC1):Aliquat 336/benzene/water/HCl. In this system the concentration of hydrochloric acid is much higher than 37 wt%. They connected with eath other through hydrogen bonding, and formed hydrochloric acid dynamic macromolecules. Small angle X-ray scattering (SAXS) indicated the formation of super-concentrated hydrochloric acid that was localized in monodispersed reversed micelles with radius of ca.9 nm or 7nm .1H NMR and FT-IR studies evidenced the saturated hydrogen bonding of such super-concentrated hydrochloric acid molecules. We also studied the optimized conditions for the preparation of SC-HC1. The results demonstrated that the best condition were as follows, ambient temperature, mAliquat 336: mbenzene=7:3, water content about 1～2%, gaseous HC1 bubbled for 2.5 h. Such a nano-sized confined micellar medium often exhibits fascinating physico-chemical properties. The hydrochloric acid dynamic macromolecules exhibited high reactivity in addition reaction. For example, addition reaction between C=C of cyclohexene and SC-HC1 can carry out under atmospheric pressure and ambient temperature. SC-HC1 can also react with benzonitrile and methanol to form benzinidic acid methyl ester hydrochloride salt, as small amount of water is added. SC-HC1 may provide other potential applications in organic synthsis and other chemical industry.