Cereal Chem. 73 (2):179-184 |
Engineering and Processing
Glycol Glucosides Process Synthesis by Reactive Extrusion with a Static Mixer as Postextruder Reactor (1).
K. Subramanian (2) and M. A. Hanna (3). (1) Journal series 11090 of the Univ. of Nebraska Agricultural Research Division. (2) Graduate research assistant, Department of Biological Systems Engineering, University of Nebraska-Lincoln. (3) Professor, Department of Biological Systems Engineering, University of Nebraska-Lincoln, NE 68503-0726. Corresponding author. Fax: 402/472-6338. E-mail: <email@example.com> Accepted October 31, 1995. Copyright 1996 by the American Association of Cereal Chemists, Inc.
Mixtures of starch (25% amylose), ethylene glycol, and concentrated sulfuric acid were extruded in a Brabender laboratory conical-twin-screw extruder with postextruder reactor modifications. Three reactor models were developed by adding a static mixer and heat exchanger to the die end of the extruder as postextruder reactor modifications. These models affected the residence time and reaction efficiency and, thus, the yield of glucosides. Process variables, including temperature, ethylene glycol-starch mole ratio, and screw speed, were permuted to enhance the yield of glucosides. High-performance liquid chromatography was used to identify the glucosides and evaluate yields. Response surface methodology was used to obtain optimum process conditions of 160°C, 20 rpm screw speed, and mole ratio of 3 with a static mixer and cooler for 91% maximum yield of glucosides.