scholarly journals Extraction and characterization of nanofibrillated cellulose from yacon plant (Smallanthus sonchifolius) stem

2020 ◽  
Author(s):  
Romaildo Santos de Sousa ◽  
Alan Sulato de Andrade ◽  
Maria Lucia Masson
Keyword(s):  
Lignin Content ◽  
Crystallinity Index ◽  
Nanofibrillated Cellulose ◽  
Lower Amount ◽  
Infrared Analysis ◽  
Technical Feasibility ◽  
Smallanthus Sonchifolius ◽  
Chemical Pulp ◽  
Chemical Pulping

This study aimed to evaluate the process of cellulose extraction from yacon stem using combined pulping and bleaching processes for produce nanofibrillated cellulose (NFC). First, chemical pulping process with NaOH was applied and, subsequently, the pulp obtained was bleached. From the chemical pulp (CP) bleached, NFC was obtained by the mechanical defibrillation in a colloidal grinder. Then, chemical composition, color, and infrared analysis of the pulps was performed. The pulping process showed a lower amount of extractives and lignin content, as a low yield and an excessively dark pulp. The CP bleached with NaClO2 showed the best results increased whiteness of the pulp. A suspension of NFC with fibers of 5–60 nm in diameter, high crystallinity index, and thermal stability was obtained. The results are promising and demonstrate the technical feasibility of obtaining NFC from yacon stems waste which is ideal to apply to other materials of the industry.

scholarly journals Influence of Different Pretreatments on the Structure and Hydrolysis Behavior of Bamboo: A Comparative Study

Materials ◽  
2019 ◽  
Vol 12 (16) ◽  
pp. 2570 ◽  
Author(s):  
Xuemin Qi ◽  
Jie Chu ◽  
Liangliang Jia ◽  
Anuj Kumar
Keyword(s):  
Lignin Content ◽  
Crystallinity Index ◽  
Cellulose Fibers ◽  
Fiber Bundles ◽  
Wet Chemistry ◽  
Naoh Pretreatment ◽  
Different Temperatures ◽  
Bamboo Fibers ◽  
The Mean

In the present study, three pretreatments of sodium hydroxide (NaOH), sulfuric acid (H2SO4), and glycerin were employed with bamboo fibers at two different temperatures of 117 °C and 135 °C, respectively. The chemical composition and structural characterization of the pretreated bamboo fibers were comparatively studied using spectroscopic and wet chemistry methods. Furthermore, the comparative hydrolysis behaviors of pretreated bamboo were studied due to the synergistic interaction between cellulases and xylanase. The NaOH treatment increased the holocellulose contents to 87.4%, and the mean diameter of the cellulose fibers decreased from 50 ± 5 µm (raw fiber bundles) to 5 ± 2 µm. The lignin content and the degree of cellulose polymerization both decreased, while the crystallinity index of cellulose and thermostability increased. The hydrolysis yields of NaOH pretreated bamboo at 135 °C increased from 84.2% to 98.1% after a supplement of 0.5 cellulose to 1 mg protein/g dry xylan. The NaOH pretreatment achieved optimal enzymatic digestibility, particularly at higher temperatures as indicated by the results.

scholarly journals NANOFIBRILLATED CELLULOSE, THE SMALL PROMISING FIBER: CHARACTERISTICS AND POTENTIALITIES

FLORESTA ◽  
2019 ◽  
Vol 49 (3) ◽  
pp. 411
Author(s):  
Eliane Lopes da Silva ◽  
Helena Cristina Vieira ◽  
Joielan Xipaia dos Santos ◽  
Cyro Ketzer Saul ◽  
Silvana Nisgoski ◽  
...  
Keyword(s):  
Plant Material ◽  
Crystallinity Index ◽  
Nanofibrillated Cellulose ◽  
Decomposition Temperature ◽  
Degree Of Polymerization ◽  
Nanometer Scale ◽  
Infrared Analysis ◽  
Original Material ◽  
Cellulose Pulp ◽  
Eucalyptus Pulp

Cellulose: an abundant, biodegradable and renewable plant material that is available all around the globe, from which nanofibrillated cellulose (a homogeneous suspension of fibers with nanometer-scale diameters) can be extracted. The nanofibrillated cellulose, in what concerns its range of application, may completely or partially replace other materials due to its particular physical properties. Knowing its characteristics and properties is important in understanding its behavior in various applications. In light of this remarks, the objective of this research was to extract the nanocellulose from bleached eucalyptus pulp through mechanical milling to characterize the resulting nanofibrillated cellulose and compare both. The nanofibrillated cellulose presented a very distinct appearance in relation to the original cellulose pulp when they were analysed in the same concentrations, demonstrating greater water absorption and fibrillar interweaving. The nanofibrillated material showed different responses in comparison to the original in terms of dimensions, thermal stability, crystallinity, viscosity, and degree of polymerization. The nanofibrillated cellulose displays the same chemical composition through infrared analysis and has diameters of around 21.7 nm, smaller than the cellulose diameter of 11.4 μm. The nanofibrillated cellulose also exhibits lower thermal resistance: its decomposition temperature was about 20 ºC lower than that of the original cellulose pulp, and its crystallinity index has decreased. As for viscosity and degree of polymerization, there was reduction of 25% compared to the original material. The results presented hereby indicate that the nanofibrillated cellulose has unique features in relation to the original cellulose pulp, which supports its application as an alternative to existing materials.

scholarly journals Determining wash loss levels in the brownstock pulp washing line using different methods

TAPPI Journal ◽  
2017 ◽  
Vol 16 (05) ◽  
pp. 253-259
Author(s):  
Riku Kopra ◽  
Olli Dahl
Keyword(s):  
Lignin Content ◽  
Oxygen Demand ◽  
Pulp Mill ◽  
Measurement Methods ◽  
Chemical Recovery ◽  
Minimal Amount ◽  
Chemical Pulp ◽  
Washing Process ◽  
Chemical Pulping ◽  
And Control

The purpose of brownstock pulp washing is to recover the maximum amount of dissolved inorganic and organic material using a minimal amount of water. Brownstock washing is a notable subprocess in chemical pulping because it has effects on the subsequent treatments of the pulp and is also the first step in the chemical recovery cycle. Without effective washing, the economic viability of chemical pulp production is affected. The performance of washing can be described in two main ways: using wash loss, which describes the amount of washable compounds in the pulp suspension that could have been removed in washing; or the dilution factor, which represents the net amount of water that is added during washing. The amount of sodium in the pulp suspension after washing has typically been used as an indicator of wash loss, usually expressed as kg sodium sulfate/ovendry ton of washed pulp. Other common measurement methods are conductivity, chemical oxygen demand (COD), total organic carbon (TOC), dissolved dry solids (DDS), and lignin concentration. Scandinavian pulp mill softwood and hardwood fiber lines were investigated using various measurement methods in the pulp phases to gain better understanding of wash loss. The concentration of DDS in the streams was measured using a refractometer and laboratory scale. The pH, conductivity, lignin content, TOC, and COD were measured to look for any correlations. Using different methods, the level differences remain constant, but it is difficult to control the washing process with sufficient precision using individual measurements. The measurement methods must also be continuous and reliable to be used to monitor and control washing.

scholarly journals Extraction and characterization of nanofibrillated cellulose from yacon plant (Smallanthus sonchifolius) stems

Polímeros ◽  
2021 ◽  
Vol 31 (2) ◽  
Author(s):  
Romaildo Santos de Sousa ◽  
Alan Sulato de Andrade ◽  
Maria Lucia Masson
Keyword(s):  
Nanofibrillated Cellulose ◽  
Smallanthus Sonchifolius

scholarly journals Fabrication and Characterization of Electrospun Poly(acrylonitrile-co-Methyl Acrylate)/Lignin Nanofibers: Effects of Lignin Type and Total Polymer Concentration

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 992
Author(s):  
Suchitha Devadas ◽  
Saja M. Nabat Al-Ajrash ◽  
Donald A. Klosterman ◽  
Kenya M. Crosson ◽  
Garry S. Crosson ◽  
...  
Keyword(s):  
Methyl Acrylate ◽  
Lignin Content ◽  
Polymer Concentration ◽  
Weight Ratio ◽  
Electrospun Nanofibers ◽  
Polymer Content ◽  
Blend Ratio ◽  
Blend Ratios ◽  
Poly Acrylonitrile

Lignin macromolecules are potential precursor materials for producing electrospun nanofibers for composite applications. However, little is known about the effect of lignin type and blend ratios with synthetic polymers. This study analyzed blends of poly(acrylonitrile-co-methyl acrylate) (PAN-MA) with two types of commercially available lignin, low sulfonate (LSL) and alkali, kraft lignin (AL), in DMF solvent. The electrospinning and polymer blend solution conditions were optimized to produce thermally stable, smooth lignin-based nanofibers with total polymer content of up to 20 wt % in solution and a 50/50 blend weight ratio. Microscopy studies revealed that AL blends possess good solubility, miscibility, and dispersibility compared to LSL blends. Despite the lignin content or type, rheological studies demonstrated that PAN-MA concentration in solution dictated the blend’s viscosity. Smooth electrospun nanofibers were fabricated using AL depending upon the total polymer content and blend ratio. AL’s addition to PAN-MA did not affect the glass transition or degradation temperatures of the nanofibers compared to neat PAN-MA. We confirmed the presence of each lignin type within PAN-MA nanofibers through infrared spectroscopy. PAN-MA/AL nanofibers possessed similar morphological and thermal properties as PAN-MA; thus, these lignin-based nanofibers can replace PAN in future applications, including production of carbon fibers and supercapacitors.

scholarly journals Chemical and Structural Characterization of Maize Stover Fractions in Aspect of Its Possible Applications

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1527
Author(s):  
Magdalena Woźniak ◽  
Izabela Ratajczak ◽  
Dawid Wojcieszak ◽  
Agnieszka Waśkiewicz ◽  
Kinga Szentner ◽  
...  
Keyword(s):  
Structural Characterization ◽  
Biogas Production ◽  
Structural Parameters ◽  
C:N Ratio ◽  
Crystallinity Index ◽  
Degree Of Crystallinity ◽  
Cellulose Content ◽  
X Ray Diffraction ◽  
Maize Stover

In the last decade, an increasingly common method of maize stover management is to use it for energy generation, including anaerobic digestion for biogas production. Therefore, the aim of this study was to provide a chemical and structural characterization of maize stover fractions and, based on these parameters, to evaluate the potential application of these fractions, including forbiogas production. In the study, maize stover fractions, including cobs, husks, leaves and stalks, were used. The biomass samples were characterized by infrared spectroscopy (FTIR), X-ray diffraction and analysis of elemental composition. Among all maize stover fractions, stalks showed the highest C:N ratio, degree of crystallinity and cellulose and lignin contents. The high crystallinity index of stalks (38%) is associated with their high cellulose content (44.87%). FTIR analysis showed that the spectrum of maize stalks is characterized by the highest intensity of bands at 1512 cm−1 and 1384 cm−1, which are the characteristic bands of lignin and cellulose. Obtained results indicate that the maize stover fraction has an influence on the chemical and structural parameters. Moreover, presented results indicate that stalks are characterized by the most favorable chemical parameters for biogas production.

scholarly journals Colored cotton wastes valuation through thermal and catalytic reforming of pyrolysis vapors (Py-GC/MS)

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Janduir Egito da Silva ◽  
Guilherme Quintela Calixto ◽  
Rodolfo Luiz Bezerra de Araújo Medeiros ◽  
Marcus Antônio de Freitas Melo ◽  
Dulce Maria de Araújo Melo ◽  
...  
Keyword(s):  
Lignin Content ◽  
Proximate Analysis ◽  
Catalytic Reforming ◽  
Pyrolysis Products ◽  
Heating Value ◽  
Colored Cotton ◽  
Benzene Toluene ◽  
Naturally Colored Cotton ◽  
Main Influence

AbstractThis study aims to analyze the products of the catalytic pyrolysis of naturally colored cotton residues, type BRS (seeds from Brazil), called BRS-Verde, BRS-Rubi, BRS-Topázio and BRS-Jade. The energy characterization of biomass was evaluated through ultimate and proximate analysis, higher heating value, cellulose, hemicellulose and lignin content, thermogravimetric analysis and apparent density. Analytical pyrolysis was performed at 500 °C in an analytical pyrolyzer from CDS Analytical connected to a gas chromatograph coupled to the mass spectrometer (GC/MS). The pyrolysis vapors were reformed at 300 and 500 °C through thermal and catalytic cracking with zeolites (ZSM-5 and HZSM-5). It has been noticed that pyrolysis vapor reforming at 500 °C promoted partial deoxygenation and cracking reactions, while the catalytic reforming showed better results for the product deoxygenation. The catalyst reforming of pyrolysis products, especially using HZSM-5 at 500 °C, promoted the formation of monoaromatics such as benzene, toluene, xylene and styrene, which are important precursors of polymers, solvents and biofuels. The main influence on the yields of these aromatic products is due to the catalytic activity of ZSM-5 favored by increased temperature that promotes cracking reactions due expanded zeolites channels.

Sign in / Sign up

Export Citation Format

Share Document