The New Jersey Institute of Technology's
Electronic Theses & Dissertations Project

Title:	The effect of ultrasound on the hydrolysis of carbohydrates
Author:	Khamis, Adel A.
View Online:	njit-etd1983-017 (v, 228 pages ~ 8.4 MB pdf)
Department:	Department of Chemical Engineering and Chemistry
Degree:	Doctor of Engineering Science
Program:	Chemical Engineering
Document Type:	Dissertation
Advisory Committee:	Kristol, David S. (Committee chair) Parker, Richard Clyde (Committee member) Perna, Angelo J. (Committee member) Sohn, Kenneth (Committee member) Venanzi, Carol A. (Committee member)
Date:	1983
Keywords:	Hydrolysis. Ultrasonic waves. Dextran. Cellulose.
Availability:	Unrestricted
Abstract:	Acid hydrolysis of dextran and cellulose were studied with and without irradiation with ultrasonic waves of different frequencies (17 - 150 KHz), and powers (0.4 - 200 w/cm2). In the case of both materials, the hydrolysis reaction was found to be first order with respect to the activity of hydrogen ions in the reaction medium. Weight average molecular weight was evaluated at different durations of the reaction course. The reaction rate of dextran was found to be proportional to the weight average molecular weight raised to the power 4/3, and raised to the power 4 for cellulose. The value of the activation energy was shown to be the same, either with or without ultrasound irradiation for both materials. It was found to be equal to 30,000 cal/mole for dextran, and 28,600 cal/mole for cellulose in a heterogeneous system. A mathematical model for the rate constant under the effect of ultrasonic waves, temperature, and hydrogen ions activity, was proposed. This model then was used to predict the optimum enhancement, which was proved to be in agreement with experimental data.