Process for producing densified halogenated dimethylhydantoins
AssigneeGreat Lakes Chemical Corporation
InventorLeon M. Cole
Life of this patent
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Abstract
Halogenated dimethylhydantoins are intimately mixed wth calcium chloride and water and compressed to provide a densified particulate solid that is capable of withstanding the stresses of automatic packaging, conveying and handling.
Claims11
A method for producing densified halogenated hydantoins comprising the steps of:
- halogenating dimethylhydantoin with a first halogenation agent in the presence of water and a source of calcium and hydroxide ions in order to form a monohalogenated hydantoin intermediate;
- thereafter halogenating the monohalogenated intermediate with a second halogenation agent in the presence of water and a source of calcium and hydroxide ions, at least one of the first and second halogenation agents including a source of chlorine;
- thereafter separating dihalogenated hydantoin product from the reaction mixture without washing whereby the separated dihalogenated hydantoin product contains calcium chloride and water.
A method for preparing halogenated dimethyl hydantoins comprising the following steps:
- introducing water and dimethylhydantoin into a reactor;
- thereafter introducing a first halogen source concurrently with calcium hydroxide in a first halogenation step, the pH being maintained at about 6.8 to 7.0 and the temperature at about 25.degree. C.;
- thereafter introducing a second halogen source concurrently with calcium hydroxide in a second halogenation step, the pH being maintained at about 6.8 to 7.0 and the temperature at about 25.degree. C.;
- thereafter filtering the reaction mixture to recover halogenated hydantoin product;
- and
- compressing the recovered halogenated dimethyl hydantoin product into a shaped form.
In a method for producing halogenated hydantoins comprising the step of reacting dimethylhydantoin with a first halogenation agent in an aqueous reaction system while adding base to form a monohalogenated hydantoin intermediate, thereafter reacting the intermediate with a second halogenation agent while continuing to add base to form a dihalogenated hydantoin product, the improvement comprising:
- using calcium hydroxide as the base;
- and
- separating the halogenated dimethylhydantoin without washing to give a product with calcium chloride and water intimately mixed therein.
Dependencies are inferred from the claim text.