Use of butanol-water mixtures for making wheat straw pulp

Wood Science and Technology (Impact Factor: 1.88). 03/1999; 33(2):97-109. DOI: 10.1007/s002260050102

ABSTRACT A central composite design was used to investigate the influence of the cooking conditions (time, temperature and butanol
concentration) for wheat straw with butanol-water mixtures on the properties of the pulp obtained (yield and holocellulose,
α-cellulose, lignin and ethanol-benzene extractives contents) and the pH of the resulting waste water. A second-order polynomial
model consisting of three independent process variables was found to accurately describe the organosolv pulping of wheat straw.
The equations derived predict the yield, the holocellulose, α-cellulose, lignin and ethanol-benzene extractives contents of
the pulp, and the pH of the waste water with multiple-R, R2, adjusted-R2 and Snedecor' F values of 0.99, 0.99, 0.99 and 310.33; 0.98, 0.97, 0.95 and 56.63; 0.91, 0.84, 0.74 and 9.14; 0.99, 0.98,
0.96 and 70.52; 0.97, 0.94, 0.92 and 40.42; and 0.98, 0.95, 0.93 and 49.33, respectively.

The process variables must be set at low values in order to ensure a high yield and pH. On the other hand, if a high holocellulose
content and low lignin and ethanol-benzene extractives contents are to be obtained, then the process variables must be set
at high values. Finally, obtaining pulp with a high α-cellulose content entails using a long cooking time and a high temperature,
as well as a low butanol concentration.

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