The influence of the process conditions of pulping of a trihybrid clone Paulownia on pulp properties for the soda anthraquinone process has been investigated in a semi-pilot scale. A composite central experimental design and a multiple regression were used to find the relationship between independent process variables and pulp properties. The ash content (0.89%) is lower and cellulose content (44.0%) is higher than those found for other species of Pauwlonia and other energetic crops. The elemental composition has a low content in S and N (0.21%) in comparation with poplar or willow. With a gross heating value of 20335 J/g, Paulownia is a suitable feedstock for use as solid biofuel. This is somewhat higher than those for hardwood, slightly higher than those for Pinus pinaster and softwood, and much higher than those for residues of food plants and agricultural crops. This supports the use of the genus Paulownia as an energy crop. The soda-anthraquinone pulping could be and adequate process for Paulownia. Fibre length (0.97 mm) is similar to hardwoods and suitable physical characteristics of paper sheets (tensile index) and acceptable chemical characteristics and yield pulping could be obtained by operating at lowintermediate temperature (163-171ºC) and alkali concentration (20%) and high or medium values for operation time (120-150 min). The pulp obtained at these conditions has suitable chemical (pulp) and physical (paper sheets) characteristics: yield (47.0%), ethanol-benzene extractives (2.22%), holocellulose contents (96.0%), α-cellulose contents (75.8%), lignin contents (8.28%), Shopper Riegler degree (23.2 ºSR), and tensile index (36.0) kN m/kg. HighlightsThe influences of the process conditions of pulping of a trihybrid clone Paulownia on pulp properties for the soda anthraquinone process have been investigated in a semi-pilot scale.The soda-anthraquinone pulping could be and adequate process for trihybrid clone Paulownia is similar to hardwoods and suitable physical characteristics of paper sheets.Trihybrid clone Paulownia is a suitable feedstock for use as solid biofuel.
BACKGROUND Lignin is one of the most abundant polymers in nature. Its physical and chemical properties confer it a high potential for various uses including the production of thermoplastic matrices. This work characterized various types of lignin obtained by alkaline delignification of paulownia with soda–anthraquinone. The delignification process was carried out with or without previous autohydrolysis. The products obtained after evaporation or acidification were used to produce polylactic acid–lignin composites. RESULTS Subjecting the raw material to autohydrolysis prior to alkaline delignification provided a spent liquor (black liquor) containing an increased amount of extracted lignin (11.9% more than without autohydrolysis) and possessing a higher calorific value (14 822 kJ kg−1) than in the absence of an autohydrolysis stage. Thermogravimetric analysis revealed a strong impact of the autohydrolysis process, which provided residual delignification fractions containing abundant lignin and no degradation products of polysaccharides or other constituents of the raw material. Mechanical dynamics analysis of composites with lignin contents from 12.5 to 30% revealed an increased elastic (storage) modulus (E'). CONCLUSIONS Soda lignin has appropriate interaction with the polylactic acid, which allows it to be used for obtaining a composite with adequate physical strength characteristics. © 2014 Society of Chemical Industry
BACKGROUND: A central composite experimental design and multiple regression were used to model the production of pulp and paper sheets from a Paulownia fortunei × tormentosa × elongata trihybrid clone. Also, the same experiments were carried out with the solid phase after autohydrolysis of the raw material.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.