ASA 130th Meeting - St. Louis, MO - 1995 Nov 27 .. Dec 01

5aPAb16. Sonolysis in liquid water without gas bubbles.

Dmitry A. Selivanovsky

Inst. of Appl. Phys., 46 Ulyanov St., Nizhny Novgorod 603600, Russia

Grigory A. Domrachev

Inst. of Metalloorganic Chemistry, Nizhny Novgorod 603600, Russia

The present paper describes the results of measurements of hydrogen peroxide concentration in water under the action of relatively low-frequency sound without cavitation. Measurements of hydrogen peroxide concentration have been carried out with a high-sensitivity chemoluminescent method which has been elaborated for these experiments. De-ionized, degassed, high-purity water has been used. Acoustic resonators of a quarter of a sound wavelength were used as vertical columns made from high-purity quartz glass. Resonance frequencies were 1.2, 5.6, and 15 kHz. The pressure amplitude in the node at the hard bottom was smaller than 0.6 atm. The formation and accumulation of hydrogen peroxide were observed. For example, for the 20 (degrees)C water temperature and 1.2-kHz frequency the rate of increasing concentration rate is equal to 2x10[sup -11] mol/(l/h) for the degassed water and 8x10[sup -10] mol/(l/h) for a solution of magnesium sulfate in degassed water with a concentration similar to the one of the sea. The absence of gas bubbles was controlled by optical and acoustical methods. It is known that the appearance of hydrogen peroxide is a result of dissociation of a part of the water molecules. A hypothesis on the possibility of dissociation of water molecules at a small energy density due to acoustical and mechanical action is discussed.