Article

Use of butanol-water mixtures for making wheat straw pulp

Wood Science and Technology (Impact Factor: 1.87). 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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    • "Therefore, non-wood fiber will play important roles in papermaking as substitutes or complements to wood. Examples of non-wood fiber resources available for paper production are wheat-straw [3] [4] [5], rice-straw [6] [7], sugarcane straw [8], reeds [9], bamboo [10], bagasse [11] [12], kenaf [13], palm oil [14], and jute [15]. Non-wood material, particularly wheat straw, was successfully exploited as the main raw material for papermaking in China because of the limited wood resource with forest coverage of only 13.94% [16]. "
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    • "These empirical models are to be preferred to theoretical ones as the latter are rather complex when more than two independent variables are involved. The potential of organosolv pulping in this context has been examined by authors such as Parajó et al. [6], Tjeerdsma et al. [7], Vázquez et al. [8], Vega et al. [9], Gilarranz et al. [10] [11] and Jiménez et al. [12] [13] [14] [15] [16] [17] [18], using alcohols, organic acids and other organic solvents; however , ethanolamine/soda mixtures have never previously been tested for this purpose. For this reason, in this work we used a central composite design to examine the influence of the independent cooking variables (viz. "
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