| 摘要 |
Herein described is a process for starch cationization comprising the steps of providing a powdered starch having a moisture content not higher than 5% by weight on the total weight of the starch and reacting it with boron trifluoride (BF 3 ) ; the reaction may be carried out by feeding a continuous flow of powdered starch into a turbo-reactor comprising a cylindrical tubular body (1), provided with at least one opening (5, 6) for the introduction of the starch and the boron trifluoride and at least one outlet opening (7), a possible heating or cooling jacket (4), a bladed rotor (8), rotatably supported in the cylindrical tubular body (1) in which it is rotated at a speed greater than 150 rpm, so as to disperse the continuous flow of starch into a flow of starch particles; a continuous stream of gaseous BF 3 is also fed into the turbo-reactor and the starch particles and the Gaseous BF 3 are centrifuged against the internal walls of the turbo-reactor, forming a thin, fluid, tubular, dynamic, highly turbulent layer, obtaining the reaction of the starch with the Gaseous BF 3 in the thin layer while the layer advances substantially in contact with the internal wall towards the outlet opening (7) of the turbo-reactor. |
