Recycling of dyed cellulosic waste
AssigneeHoechst Aktiengesellschaft
InventorAndreas von der Eltz
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Abstract
A process which comprises suspending a reactive-dyed cellulose material, optionally in mixture with pulp, in an alkali metal hydroxide solution (alkali cellulose), optionally subjecting the alkali cellulose to the action of a reducing sulfur compound at a temperature from 20.degree. to 80.degree. C., then allowing the alkali cellulose to ripen at temperatures from 30.degree. to 80.degree. C. for at least 30 minutes, dissolving the alkali cellulose at a temperature from 10.degree. to 30.degree. C. by conversion with carbon disulfide into the xanthate, and spinning the xanthated alkali cellulose into fibers, makes it possible to recycle cellulosic waste textiles into similarly colored or colorless cellulose fiber materials.
Claims17
A process for recycling dyed cellulosic waste into reusable viscose, which comprises suspending a reactive-dyed cellulose material in an alkali metal hydroxide solution to produce alkali cellulose, then allowing the alkali cellulose to ripen at temperatures from 30.degree. to 80.degree. C. for at least 30 minutes, dissolving the ripened alkali cellulose at a temperature from 10.degree. to 30.degree. C. by conversion with carbon disulfide into a reusable viscose.
Dependencies are inferred from the claim text.