Process for the preparation of pure trioxane
AssigneeHoechst Aktiengesellschaft
InventorsKarl Muck, Helmut Schlaf, Siegbert Rittner
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Abstract
In the process for the preparation of pure trioxane by continuous or semicontinuous crystallization processes, if alkaline organic compounds are added no flocks appear after more than 120 hours of operation. As a result, blockage of the crystallization unit is prevented and problem-free running is made possible.
Claims13
A process for the preparation of a highly pure trioxane by crystallization of a trioxane mixture, which comprises adding an amine to a crystallization step or to a crystallization apparatus section in which in both the purity of the starting trioxane is at least 95% by weight, said crystallization is accompanied by at least one process step corresponding to a washing or sweating operation.
A process for the preparation >95 weight-% pure trioxane by multi-step crystallization of an impure trioxane containing up to about 5 weight-% impurities, comprising:
- carrying out the multi-step crystallization in the presence of an amine, wherein said crystallization is accompanied by at least one process step corresponding to a washing or sweating operation and
- removing the amine and recovering purified trioxane.
A process for the preparation of highly pure trioxane by crystallization of a trioxane mixture, which comprises adding an amine to the trioxane mixture in the crystallization step or to the apparatus section in which the purity of the trioxane is 95 to 99.0% by weight, said crystallization is accompanied by at least one process step corresponding to a washing or sweating operation.
Dependencies are inferred from the claim text.