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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: This paper reports on the influence of independent variables in the pulping of olive wood trimmings [viz. cooking temperature (165–195°C) and time (30–90min), ethanolamine concentration (5–15%), soda concentration (2.5–7.5%) and liquid/solid ratio (4–6)], on the yield and kappa number of the pulps and breaking length, burst index and tear index of the resulting paper sheets. By using a central composite factorial design, equations that relate each dependent variable to the different independent variables were obtained that reproduced the experimental results for the dependent variables with errors less than 15%. These equations could be used to find the suitable operations conditions, so that operating with not too high values of operating variables (with the consequent minor costs of capital and of operation) pulps could be obtained by acceptable strength properties. Optimizing pulp yield, the kappa number and the strength properties of the resulting paper sheets entails using rather different conditions in each case. Obtaining acceptably strong paper sheets while saving on immobilized capital through the use of smaller facilities and less chemical reagents entails using a medium soda concentration and low values of all other independent variables. In this way, the yield is 22.2% lower, the kappa number 42.5% higher, and the breaking length, burst index and tear index 6.2, 29.1 and 29.6%, respectively, lower than their optimum values; in any case, the strength properties increase although the pulp was suitably refining. [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]