Hydrogen Peroxide → DL-Arginine Cerium

Participants

Reaction Conditions

Reaction Steps

Into a 600 ml glass beaker containing a magnetic stir bar was introduced 500 ml of high purity (HP) water. A 2.006 gm quantity of DL-arginine was dissolved in this volume and the solution was heated to about 40° C., forming an alkaline solution. A 10.0 gm quantity of Ce(NO3)3·6(H2O) was added, dissolved with stirring, resulting in a solution pH of about pH 6. The molar ratio of DL-arginine to cerium ion was 0.5. Then a 10 ml solution containing 1.20 gm of 50% H2O2 (0.75 molar ratio of H2O2 to cerium ion) was added slowly to the cerium and arginine solution mixture, which lowered the pH to about 4, and formed a turbid white suspension. The pH was further adjusted to about 3 by the addition of 1N HNO3, thereby forming a clear suspension. The reaction product was then held at 40° C. for 1 hour. After cooling, the final product dispersion was a clear liquid that displayed a high degree of Tyndall scattering when illuminated with a low intensity LASER beam, indicating it contained well-dispersed colloidal particles. Particle size analysis by dynamic light scattering indicated a hydrodynamic diameter of 7.7 nm with a polydispersity of 0.27.

Provenance & Evidence