Abstract
Hydrolysis of ZrOCl_2 aqueous solution was subjected to high intensity ultrasound. It should be noted that this slow reaction promptly proceeded at 60℃ in the presence of ultrasound, while usually in the absence of ultrasound it takes tens of hours at 100℃. ZrOCl_2+(n+1)H_2O→ZrO_2・nH_2O+2HCl Direct sonication using an ultrasonic homogenizer appeared inappropriate due to considerable erosion of Ti horn in the acidic condition. Employed was a standing-wave sonicator with a thermostat. Comparing two frequencies of 28 and 45 kHz, the latter was found to be effective in the enhancement of the hydrolysis. Products after centrifuged and dried were amorphous zirconia. Argon substitution of the starting solution increased the formation of zirconia.
