PAPER PHYSICS: Ultrasonic treatment of secondary fibers to improve paper properties

Manfredi, Mauro; Oliveira, Rubens Chaves de; Reyes, Rafael Ignacio Quezada; Silva, Juliana Cristina da

doi:10.3183/npprj-2013-28-02-p297-301

Cited by 9 publications

(4 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…O teor de hemiceluloses está ligado tanto aos processos de polpação da madeira quanto à qualidade do produto. As hemiceluloses são muito hidrofílicas, devido às suas estruturas ramificadas e amorfas, o que facilita o inchamento das fibras através da absorção de água, promovendo a lubrificação interna e aumentando tanto a flexibilidade das fibras quanto a área de contato entre as mesmas (MANFREDI, 2013).…”

Section: Características Físico-químicas Da Madeira Pterogyne Nitensunclassified

Determinação da composição química e potencial de polpação da madeira <i>Pterogyne nitens</i> Tul.

et al. 2019

View full text Add to dashboard Cite

Determinação da composição química e potencial de polpação da madeiraPterogyne nitens Tul.Determination of the chemical composition and the wood pulping potential of Pterogyne nitens Tul. ResumoA grande dependência por madeiras das espécies dos gêneros Eucalyptus e Pinus associada à busca por produtos de diferentes qualidades impulsionam estudos acerca de madeiras alternativas para fins industriais, principalmente de espécies do bioma Caatinga, pouco estudado para fins florestais. O objetivo deste estudo foi caracterizar quimicamente a madeira da espécie Pterogyne nitens assim como analisar seu potencial para produção de polpa celulósica. Foram colhidas três árvores representativas de 9 anos, em um plantio experimental localizado na Universidade Estadual do Sudoeste da Bahia -Campus Vitória da Conquista, e amostradas cinco seções do fuste entre as posições 0, 25, 50, 75 e 100% da altura comercial.Os toretes foram transformados em cavacos e homogeneizados formando uma amostra composta representativa para a análise de densidade básica e composição química completa, bem como para a realização da polpação Kraft (cinco cozimentos utilizando diferentes cargas de álcali efetivo objetivando um Número Kappa 18). A densidade básica da madeira Pterogyne nitens foi de 641 kg/m³, sua composição química apresentou 41,9% de celulose, 24,7% de hemiceluloses, 26,5% de lignina, 7,3% de extrativos e 0,5% de cinzas. O rendimento do cozimento para Número Kappa 18 foi 46,4% e viscosidade 1075 dm 3 /kg. A espécie não se apresentou como uma alternativa interessante para a produção de polpa celulósica (baixo teor de celulose e rendimento depurado), mas bastante promissora para aplicação na área de energia da madeira. AbstractThe strong dependence on wood from species like Eucalyptus and Pinus genus, associated to the search for products of different qualities, led to studies about alternative wood for industrial use, mainly about species from the Caatinga biome and which is understudied for forest purposes. The aim of this study was to characterize chemically the wood from the species Pterogyne nitens and analyze its potential for pulp production. Three representative trees of 9 years old were harvested in an experimental plantation located in the southwest of Bahia state, the University of Vitória da Conquista Campus, and sampled five short logs at 0, 25, 50, 75 and 100% of the commercial height. Logs were transformed in chips and homogenized to obtain a representative composed sample for the total chemical analysis (cellulose, hemicelluloses, lignin, extractives and ashes content) and Kraft pulping (five cooking using different effective alkali loads to establish Kappa number 18). Pterogyne nitens wood basic density was 641 kg/m³, its chemical composition showed contents of cellulose (41.9%), hemicelluloses (24.7%), lignin (26.5%), extractives (7.3%) and ashes (0.5%). Pulping yield at Kappa number 18 was 46.4% and viscosity 1075 dm 3 /kg. The species did not suggest as an interesting alternative for pulp production (low cellulose conte...

show abstract

Section: Características Físico-químicas Da Madeira Pterogyne Nitensunclassified

Determinação da composição química e potencial de polpação da madeira <i>Pterogyne nitens</i> Tul.

et al. 2019

View full text Add to dashboard Cite

show abstract

“…To adapt the refiners to processing of primary and secondary fibers, it is necessary to change the operation principles. Conventional refining has been replaced by unconventional methods of fibre treatment such as ultrasound (Tatsumi et al 2000;Manfredi et al 2013), enzymes (Gil et al 2009;Cui et al 2015), steam explosion, pressure fluctuation, low temperature treatment (Young 1980;Bajpai 2005), and cavitation (Shankar et al 2018). Unfortunately, none of these methods have brought any crucial progress in this field (Przybysz and Przybysz 2013).…”

Section: Introductionmentioning

confidence: 99%

Comparison of the beatability for fast-growing plants, softwood, and hardwood sources of fibers

Małachowska

Dubowik²

2019

BioRes

View full text Add to dashboard Cite

Refining is a primary unit operation that has a large impact on the quality of paper products and cost of production. The refining process of cellulose fibers is the most energy-intensive step in the preparation of paper pulp. High energy consumption during the refining process has motivated researchers to improve the economics of the process without decreasing the strength of the paper produced. This objective can be realized through easily refined pulps that are produced from alternative vegetal fibrous raw materials. This work compares the energy consumption of refining soft, hardwood, and fast-growing fibrous materials to 30 °SR. The goal was to reduce energy consumption while maintaining the strength properties of the paper received. For this purpose, cellulose pulps from fast growing plants including poplar, larch, and grasses were used.

show abstract

“…To reduce the effect of the previous production cycles on new products, authors suggest some methods to improve the quality of papers produced from recycled fibers, such as the addition of chemical and other agents, refinement and use of ultrasound (Wistara;Raymond, 1999;Zhang et al, 2002;Heydari;Afra 2013;Manfredi et al, 2013). In particular, the use of nanofibrillated cellulose as an agent in addition to recycled fibers can enable obtaining new nanostructured products with excellent mechanical properties.…”

Section: Introductionmentioning

confidence: 99%

Nanofibrillated Cellulose as an Additive for Recycled Paper

Viana

Potulski

Muñiz

et al. 2018

CERNE

View full text Add to dashboard Cite

In this work, recycled papers werereinforced with Eucalyptus sp. NFC obtained through mechanical defi brillation in a grinder. Addition of 10 % provided the best results, with improvement of tensile, burst and tear resistance of 97, 133 and 104 %, respectively, in comparison to normal papers. The papers' apparent density signifi cantly increased with the addition of NFC due to the lower porosity and more compact structure presented when compared to the treatments without the addition of NFC. The addition of NFC signifi cantly improved the physical and mechanical properties of the recycled papers when compared to normal papers.

show abstract

PAPER PHYSICS: Ultrasonic treatment of secondary fibers to improve paper properties

Cited by 9 publications

References 0 publications

Determinação da composição química e potencial de polpação da madeira <i>Pterogyne nitens</i> Tul.

Determinação da composição química e potencial de polpação da madeira <i>Pterogyne nitens</i> Tul.

Comparison of the beatability for fast-growing plants, softwood, and hardwood sources of fibers

Nanofibrillated Cellulose as an Additive for Recycled Paper

Contact Info

Product

Resources

About