| 摘要 |
The invention concerns the acetlyation of fibrous materials, such as lignocellulose fibres. The fibres in sliver form are wound into narrow rolls so as to have a central aperture. The rolls are then slid onto a central, perforated tube of a cylindrical treatment cage which has an outer cylindrical perforated wall, so that the rolls form a compacted stack of fibres. The cage is placed in a treatment tank, which is then sealed closed. Acetic anhydride is introduced into the sealed tank and a circulating means then circulates it through the cage and the stack of fibres, thereby to acetylate the fibres. The tank may be heated, and the fibres may be subjected to a pre-acetylation step of having inert gas circulated therethough, and a post-acetylation stripping of residual medium by having steam circulated therethrough, using the same circulating means. An effective method of safely acetylating fibres is achieved. |
