Monday, September 24, 2012


Many cellulose research centres throughout the world are now actively enaged in developing and studying new cellulose solvent systems and in spinning quality rayon fibres. This article compares the use, advantages and limitations of amine oxides, liquid ammonia and ammonium salt, lithium chloride with dimethylacetamide (DMAc) as three of the most recently described new solvent systems. The amine oxide and lithium chloride/DMAc systems are both cost-competitive with viscose on a greenfield installation basis. It is considered that additional work is needed to find an even more economical system with further reduced recovery and recycling costs. There is now little doubt that any further rayon production will not involve the viscose process and that some form of recyclable solvent system will be employed.

Turbak A F,. Tappi J., vol. 67, no. 1, Jan. 1984, pp 94-96

Al Turbak was not alone in thinking that new viscose plants would never again be built.  The rayon market was shrinking and viscose plants were closing at this time.  30 years later it was evident that viscose technology was preferred to solvent spun (lyocell) technology by the then leading exponent of both - Lenzing.

It is interesting to see that Al felt something more economical than NMMO would be needed for success.

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