摘要:
The present invention relates to the continuous preparation of alcohol- and plasticizer-free finished nitrocellulose solutions having a particularly low water content by partial distillative falling-film evaporation of comparatively water-rich, optionally emulsion-like crude nitrocellulose solutions which are preferably provided by dissolving nitrocelluloses of the customary solid forms offered, which are known to be initially water-moist as a result of the preparation, in preferably ethyl acetate.
摘要:
A process is described for the continuous preparation and/or workup of polysaccharide derivatives by reaction and/or conditioning in a suspension with liquid reaction partners, in which, in accordance with FIG. 1, a) a preferably pumpable suspension stream of solids SE and liquid phase LE, if appropriate preheated to 185° C., is continuously introduced into the top region of a column, if appropriate under a pressure buffer of up to 6×106 Pa, which is virtually filled with the same liquid phase L, or another process-specific liquid phase L of preferably the same temperature, then b) the solids SE sediments freely due to the action of gravity through the liquid phase L to the column bottom, the solids SE converting to the solids SA by reaction and/or conditioning with the liquid phase L and c) possibly ascending gases G are discharged from the column via the column top and d) the solids SA is again continuously discharged as a suspension stream at the column bottom continuously by adding liquid phase LR taken off at the column top at a constant column filling level and transported in a separate connection, or liquid phase LN newly added from the outside to the column bottom.
摘要:
The present invention relates to the continuous preparation of alcohol- and plasticizer-free finished nitrocellulose solutions having a particularly low water content by partial distillative falling-film evaporation of comparatively water-rich, optionally emulsion-like crude nitrocellulose solutions which are preferably provided by dissolving nitrocelluloses of the customary solid forms offered, which are known to be initially water-moist as a result of the preparation, in preferably ethyl acetate.
摘要:
A process for producing compacted free-flowing nitrocellulose based lacquer raw materials is described. The process involves pressing a nitrocellulose based lacquer feed material, which is moistened with alcohol or water, through the holes of a die. The pressing step may be performed by means of at least one circulating breaker. The process optionally comprises shearing off the compacted lacquer raw material into pieces of selected length, below the die. The compacted nitrocellulose based lacquer raw materials prepared by the process of the present invention are free flowing and have a moisture content of at least 25%.