Dissolution of dissolving pulp in alkaline solvents after steam explosion pretreatments

• In this project different aqueous based solvent systems were investigated for the dissolution of steam exploded (STEX) dissolving pulps prior to a coagulation step for preparation of textile fibers. The pulp samples studied could, to a large degree, be dissolved in a NaOH/urea/thiourea system, but there are always residuals, irrespective of the conditions. The dissolution process appeared to be kinetically controlled, as prolonged retention time decreased the amount of residuals. A pre-cooled NaOH/urea/thiourea system, and a retention time of 60 h generated the lowest amount (6%) of residuals of the STEX pretreated dissolving pulp studied. Some fundamental results are described and a model for dissolution of dissolving pulp fibers is proposed.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Kemiteknik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Chemical Engineering (hsv//eng)

Nyckelord

alkaline solvent systems

cellulose

dissolution

steam explosion

Publikations- och innehållstyp

kon (ämneskategori)

ref (ämneskategori)