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Abstract: This work aims at the characterization and the biorefinery of Hesperaloe funifera by means of the use of its three main components: separating hemicellulose by hydrothermal treatments; cellulose pulp by various pulping processes (soda, soda–anthraquinone, ethanolamine, ethyleneglycol, diethanolamine and diethyleneglycol); and exploitation of pulping liquor, rich in lignin, by pyrolysis and gasification processes. The contents in lignin, α-cellulose, holocellulose, hemicellulose, ethanol–benzene extractives, hot water solubles, 1% NaOH solubles and ash of H. funifera were found to be 7.3%, 40.9%, 76.5%, 35.6%, 4.0%, 13.5%, 29.5% and 5.9%, respectively. The mean fibre length, 4.19mm, exceeds those for some non-wood materials. By using sulfuric acid in the hydrothermal treatment (170°C, 0, 20min after reaching operating temperature, 8 liquid/solid ratio, and 0.3% sulfuric acid), gives a liquid fraction containing 4.62% of glucose, 10.56% of xylose, 1.28% of arabinose, and a solid fraction with a solid yield of 57.0%. The best pulp of Hesperaloe pulp was obtained by cooking with 10% NaOH and 1% anthraquinone at 155°C for 30min, exhibited good values of yield (48.3%), viscosity (737mL/g), Kappa number (15.2), tensile index (83.6Nm/g), stretch (3.8%), burst index (7.34kN/g) and tear index (3.20mNm2/g). Moreover, the soda–anthraquinone pulps of raw material are better than the pulps from solid fraction of hydrothermal treatments. Finally, acidification (pH 6) of soda–anthraquinone pulping liquor was carried out to separate lignin-rich solids, by which pyrolysis gave a gas containing 1.13% H2, 31.79% CO and 1.86% CH4 by weight. Gasification of the same sample provided a gas containing 0.18% H2, 24.50% CO and 17.75% CH4. [Copyright &y& Elsevier]

Abstract: Rice straw was used as an alternative raw material to obtain paper pulp. Pulping was done by using high-boiling point organic solvents of decreased polluting power relative to classical (Kraft, sulphite) solvents but affording operation at similar pressure levels. The holocellulose, α-cellulose and lignin contents of rice straw (viz. 60.7, 41.2 and 21.9%, respectively) are similar to those of some woody raw materials such as pine and eucalyptus, and various non-wood materials including olive tree prunings, wheat straw and sunflower stalks. Pulping tests were conducted by using ethyleneglycol, diethyleneglycol, ethanolamine and diethanolamine under next operating conditions: 80% solvent, 180°C and 150min. The solid/liquid ratio was 6. The amine solvents were found to provide pulp with better properties than did the glycol solvents. Diethanolamine pulp exhibited the best viscosity, Kappa index, drainage index and burst index (viz. 956mL/g, 17.0, 21°SR and 1.23kN/g, respectively). Paper made from ethanolamine pulp exhibited the best stretch (1.99%), tear index (0.44mNm2/g) and brightness (41.7%). [Copyright &y& Elsevier]

Abstract: The influence of operational variables in the pulping of vine shoots by use of ethanolamine [viz. temperature (155 to 185°C), cooking time (30 to 90min) and ethanolamine concentration (50 to 70%, v/v)] on the properties of the resulting pulp (viz. yield, kappa index and viscosity) and paper sheets (breaking length, stretch, burst index, tear index and brightness) was studied. A central composite factorial design was used in conjunction with the software ANFIS Edit Matlab 6.5 to develop fuzzy neural model that reproduced the experimental results of the dependent variables with errors less than 10%. The model is therefore effective with a view to simulating the ethanolamine pulping process. [Copyright &y& Elsevier]