Alpha-cellulose Content Research Articles

Synthesis of microcrystalline cellulose from pretreated cotton obtained from Bombax ceiba L. and its characterization

Microcrystalline cellulose (MCC) is an important ingredient in pharmaceutical, food, cosmetic and other industries. Microcrystalline cellulose was synthesized from the alpha cellulose content of pretreated cotton, Bombax ceiba L. by hydrochloric acid hydrolysis. The prepared microcrystalline cellulose was characterized by determining some physicochemical properties such as pH, angle of response, Carr’s index, Hausner ratio, moisture content etc and compared with commercial-grade microcrystalline cellulose that is used in pharmaceutical industry as excipient. Scanning electron microscope (SEM) and FTIR data represented the structure and particle characterization of sample. Thermal gravimetric analysis (TGA) showed the thermal stability of the sample. The results showed that the yield of microcrystalline cellulose was about 85% and compared favorably with the commercial grade microcrystalline cellulose as well as conformed official specifications for microcrystalline cellulose in British Pharmacopeia. It was also found that the duration of acid hydrolysis affected the polymeric form of the processed alpha cellulose.Bangladesh J. Sci. Ind. Res. 50(3), 199-204, 2015

A novel method for rapid determination of alpha-cellulose content in dissolving pulps by visible spectroscopy

A novel method has been developed for the rapid determination of the alpha-cellulose content in dissolving pulps. After alkaline treatment of the sample, the alkaline-soluble portion of the filtrate was transformed into colloids in a medium containing ethanol (80 %). The colloid solution was then measured by visible spectroscopy. The results showed a linear correlation between the root of absorbance at 500 nm and the amount of the colloid in the solution. The linear regression coefficient (R2) was 0.986 for eucalyptus pulp and 0.997 for pine pulp. A universal calibration model has been developed using the partial least square regression technique. The model is robust, and the results have good accuracy, with R2, root mean squared error cross validation, and relative prediction errors of 0.972, 0.492, and 0.51 %, respectively. The model also performed well when compared with the results from the traditional alpha-cellulose measurement method. In summary, the new method is simple, practical and suitable for use to determinate alpha-cellulose content in dissolving pulps in laboratory or industrial applications.

Evaluation of Hydro-Mechanical Properties and Root Architecture of Plants for Soil Reinforcement

Plant helps to stabilize the masses of soil via hydrological and mechanical means. The effects of vegetation on soil depend on the overall root growth, architecture and its hydro-mechanical functions. Three leguminous plants, Leucaena leucocephala, Pterocarpus indicus and Peltophorum pterocarpum were evaluated in terms of their hydro-mechanical characteristics and root architecture for soil reinforcement. The results show that L. leucocephala exhibited the highest hydrological properties such as diurnal transpiration, water absorption capacity and soil matric suction (SMS). Regarding mechanical characteristics, L. leucocephala exhibited the highest root tensile strength and cellulosic components in the root. Interestingly, L. leucocephala also showed a higher root length, volume and tips than Pterocarpus indicus and Peltophorum pterocarpum . The SMS was strongly (r = 0.79) correlated with leaf area index (LAI), indicating that high LAI improved SMS. In conjunction with the cellulosic composition, root tensile strength of the species studied was highly correlated with the alpha-cellulose content (r = 0.9) and showed that high alpha-cellulose content of roots improved mechanical properties of plants to provide reinforcement in the soil. The highroot tensile strength, root cellulosic composition and VH-type root of L. leucocephala make the species special for growing as a soil reinforcing plant. In conclusion, L. leucocephala properties revealed that it possessed excellent hydro-mechanical properties and root architecture and can be planted on slopes for soil reinforcement.

Cotton Linter Crystallinity Variations Caused by Electron Beam Irradiation and Acid Treatment

ABSTRACT The crystallinity and molecular weight of cotton linter need to be controlled to be more easily dissolved in NMMO during manufacture of clothing fabrics. Electron beam irradiation and sulfuric acid treatment were used as pre-treatment to reduce molecular weight of cotton linter more efficiently, and after the pre-treatment, peroxide bleaching was followed in alkaline condition. After those processes, the crystal-line indices of the cotton linters were measured by XRD method, and other properties such as their alpha cellulose contents and degree of polymerization were measured. It was found that the crystallinity index of cotton linter was decreased as the irradiation of electron beam increased while increased as the dose of sulfuric acid increased. These results strongly suggested that electron beam damaged the crystalline structure of the cellulose directly while sulfuric acid dissolved mostly non-crystalline area of the cellu-lose structure. Keywords: Cellulose crystallinity, electron beam irradiation, sulfuric acid, alpha cellulose, degree of polymerization, cotton linter

Comparison of hot-water extraction and steam treatment for production of high purity-grade dissolving pulp from green bamboo

The performance of hot-water extraction (HWE) and steam treatment (ST), followed by kraft pulping were compared for production of high purity-grade dissolving pulp from green bamboo. With the same prehydrolysis intensity (represented by the P-factor), the fractionation efficiency of HWE is far lower than that of ST. Because of lower removal of non-cellulosic components, the solid residue from HWE (even at approximately double the prehydrolysis intensity, P-factor = 1,379) required more active alkali (AA) during kraft pulping to obtain a cellulose purity equivalent to that achieved by the ST (P-factor = 756)-kraft process. To reach equivalent hemicellulose removal, HWE required more severe intensity than ST. However, FTIR and SEM characterizations of solid residue confirmed that intensified HWE resulted in significant lignin condensation. Antagonistic effects of hemicellulose removal and lignin condensation extent on subsequent kraft pulping were therefore more apparent in HWE than that in ST. Under the same kraft pulping conditions, lignin condensation from a severely intensified HWE process (P-factor = 2,020) caused greater cellulose yield and viscosity loss than that found for ST. Finally, at a given residual pentosan or lignin content, the cellulose yields from all HWE-kraft pulps were about 3 % lower than those from ST-kraft pulps. Consequently, based on an optimally setup chlorine dioxide bleaching stage, a cellulosic pulp with alpha-cellulose content of 97.6 % and viscosity of 927 mL/g was successfully produced from a ST-kraft pulp (P-factor = 756, AA = 19 %).

The role of sodium ions on the development of micro-sized pores in a high alpha-cellulose content woody biomass under ambient temperature

Abstract Woody biomass can be used as excellent raw materials for producing porous carbon materials such as active carbon or carbon molecular sieve, due to their excellent absorption ability. However, the formation mechanism and relations between graphite spherical grains and the development of micro-sized pores in the woody biomass during carbonization treatment are still unknown. In this study, a stepwise heat-treatment process was used to treat high alpha-cellulose biomass raw materials; several metal oxides were used as catalysts. From our study results, only the Na2O catalyst can cause the swelling of graphite spherical grains at 1500 °C, and leave holes sized 0.5–1 um on the cytoskeleton surface of carbon materials. Therefore, we can produce carbon materials with precision-controlled pore sizes by adding sodium oxide as the catalyst. We expected that this pretreatment of biomass could reduce the water vapor use amount by about 40%–60% in the production of activated carbon.

Abatement of Metal Ion Contents from Cotton Linter for the Manufacture of Regenerated Cellulose

ABSTRACT The reduction of metal ion from the cotton linter for the preparation of NMMO (N-methylmorpholine N-oxide)-based dissolving pulp was investigated. The NMMO-based dissolving pulp was usually used for the manufacture of high quality fabrics, and need to have high alpha cellulose content and high brightness. NMMO, which is environmentally friendly, and reusable after recovering process, is very sensitive to the metal ions such as Cu, Fe, Mg, and Cr. Electron beam, sulfuric acid, acetic acid, and ozone treatment before bleaching were used and the concentration changes of the metal ions were compared to that of EDTA, a chelating agent. It was found that both acid treatments (sulfuric and acetic acid) were very effective and comparable to EDTA treatment at the same dosage in metal ion reduction, but electron beam and ozone treatment were not. The sulfuric acid treatment turned out to be effective in metal ion reduction, and most inexpensive. Keywords : Cotton linter, electron beam, sulfuric acid, acetic acid, ozone, metal ion

Why fine tree roots are stronger than thicker roots: The role of cellulose and lignin in relation to slope stability

Plant roots help to reinforce the soil, increase slope stability and decrease water erosion. Root tensile strength plays an important role in soil reinforcement and slope stabilization. The relationship between tensile strength and internal chemical composition of roots is unknown due to limited studies. Thus, it is difficult to determine why root tensile strength tends to decrease with increasing root diameter. In this study, biomechanical and biochemical tests were performed on the roots of Chinese pine (Pinus tabulaeformis) to determine the relationships among tensile strength and the contents of the main chemical composition: cellulose, alpha-cellulose and lignin in the roots with different diameters. Our results confirmed that the tensile strength of Chinese pine roots decreased with increasing root diameter, and this relationship might be a power function. The chemical contents of the roots and root diameter were also related to each other with significant power regression. With increasing root diameter, the cellulose content and alpha-cellulose content increased, but the lignin content decreased. In addition, the lignin content exhibited a significantly positive relationship with tensile strength. Furthermore, the ratios of lignin/cellulose and lignin/alpha-cellulose decreased with increasing root diameter following significant power regressions, and they also demonstrated a positive relationship with tensile strength. Taken together, these results may be useful for studies on root tensile strength, soil reinforcement and slope stability.

Effect of PFI mill and Valley beater refining on cellulose degree of polymerization, alpha cellulose contents, and crystallinity of wood and cotton fibers

Manufacturing fabrics from dissolving cellulosic pulp is increasing in these days. For making high quality of cellulose-based fabrics, control of cellulose DP (degree of polymerization), its alpha cellulose content, its brightness, and its crystallinity are important. To process the cellulosic raw material, refining of cellulosic fibers is essential, and it is important to know if refining affects those important cellulose properties. The effects of PFI mill and Valley beater refining on the alpha-cellulose content, cellulose DP, crystallinity, and paper mechanical properties of wood and two different cotton fibers were studied. The results showed that PFI mill refining rarely affected those properties. Fibers refined by a Valley beater displayed a small reduction in fiber length in comparison with those refined by a PFI mill. However, the Valley beater refining method produced almost no changes in cellulose properties, either. The refining process seemed to have very little effect on the cellulose DP, crystallinity index, or alpha-cellulose content until the freeness decreased to around 300 mL CSF for wood and 100 mL CSF for cotton fibers, respectively. There were also no differences in tensile strength development in two refining methods.

Eco-Friendly Extraction and Characterization of Cellulose from Oil Palm Empty Fruit Bunches

Cellulosic fibers in Oil Palm Empty Fruit Bunches (OPEFB) are tightly packed with lignin, hemicelluloses, small depositions of wax, and inorganic elements. In the present work, eco-friendly reagents with low concentrations of 20% (v/v) formic acid and 10% (v/v) of 30% hydrogen peroxide were employed at 85 ºC for the extraction of cellulose from OPEFB. The yield of 64% (w/w) achieved was among the highest ever reported. Based on the XRD, the alpha-cellulose content was 93.7% with a high crystallinity of 69.9%. The average diameter was 13.5 μm with structural evidence of separated fibrils as investigated by FESEM. The TEM analysis suggested that the material was crystalline and its geometry was a monoclinic structure. The FTIR spectral peaks representing wax and hemicelluloses at 1735 cm-1 and 1375 cm-1, respectively, and lignin at 1248 cm-1 and 1037 cm-1, were not observed in the extracted OPEFB-cellulose spectra. Based on the TGA results, thermal stability at 325 ºC with a single degradation curve suggests the purity of OPEFB-cellulose.

Estimation of the Ratio of Vascular Bundles to Parenchyma Tissue in Oil Palm Trunks using NIR Spectroscopy

In order to use oil palm trunks more effectively, a new method was investigated to estimate the weight-based ratio of vascular bundles (VB) to parenchyma tissue (PT) in study materials taken from oil palm trunks, by using near infrared (NIR) spectroscopy based on chemical analyses of the composition. The VB and PT were carefully separated by hand from oil palm trunks using a polarizing microscope to ensure purity, and then they were mixed at certain ratios. As the VB ratio was increased, extractives, lignin, hemicellulose, and starch contents decreased, while the alpha-cellulose content increased. By using NIR spectroscopy coupled with partial least squares regression analysis, we could predict the ratio of VB to PT with an accuracy of R2 = 0.99. Absorption peaks significantly affecting estimation were observed at 1929, 2104, 2276, and 2335 nm, which were assigned to the chemical compositions of cellulose and starch. The NIR absorbance is considered to reflect the ratio of VB to PT, according to the compositions of cellulose and starch in oil palm trunks.

Comparing knee clinical examination and MRI findings with arthroscopy results in meniscus ruptures among 122 patients admitted at Qaem hospital from 0212 to 0210

The present work leads to sustainability (responsible management of resources consumption) of both paper and sugar industries. It, simultaneously, upgrades recycled waste paper (namely old newsprint) and creates a new use for molasses (an important byproduct of the sugar industry). This study introduces -for the first time world wide- a novel environmentally safe approach to upgrade recycled natural cellulose fibers (waste paper namely old newsprint), for use as specialty paper green nanocomposites suitable for several advanced purposes. The recycled cellulose fibers are upgraded by increasing their alpha cellulose content, and restoring their natural nanoporous structure, which is -normally- collapsed due to the first cycle of papermaking. Molasses is then incorporated into this restored nanoporous structure to obtain paper green nanocomposites filled with kaolin in presence of molasses. In comparison to conventionally recycled waste paper, the green paper nanocomposites -produced in this work- exhibit high dry and wet strength, and a surprisingly tremendous retention of inorganic fillers used in papermaking. This was achieved through a green nanotechnology process, where the solvent used is water (the ideal green solvent). The input and output components are renewable environmentally safe materials i.e. waste paper (cellulose fibers) and molasses (a by product of the sugar industry). The procedures used are simple physical processes conducted at room temperature rather than hazardous chemical reactions. Thus, saving energy, and decreasing the risk of chemical and thermal accidents, pollutive releases, explosions, and fires.

Protozoidal activities of Eucalyptus cammeldulensis, Dalbergia sissoo and Acacia arabica woods and their different parts on the entozoic flagellates of Heterotermes indicola and Coptotermes heimi

Different parts of three woods of Eucalyptus cammeldulensis , Dalbergia sissoo and Acacia arabica were analyzed for their toxicity potentials against two species of termites ( Heterotermis indicola and Coptotermis heimi ). Termite workers were allowed to feed on 2 g complete wood powder of plant species and their parts, including; bark, sapwood and heartwood. Samples of flagellates were collected after each 24 h from the termites’ gut and they showed a significant variation in their mortality rate as per the wood species and their parts used in the experiments. After six days, mortality rates in flagellates were 100% with all wood parts of E. cammeldulensis , whereas it was 87.2, 47.61 and 100% with bark, sapwood and heartwood of D. sissoo respectively. However, in the case of A. Arabica , only bark inflicted 44.5% mortality on the flagellates in termites on the 6th day. It is revealed from the results that different woods or their specific parts have some specific toxic compounds that inflicted varying degree of toxicity on enteric flagellates of termites. Considering the toxigenic nature of different woods and their respective parts, the three woods; E. cammeldulensis , D. sissoo and A. arabica and their parts barks, sapwoods and heartwoods were analyzed for the presence of water soluble constituents such as lignin, benzene-ethanol soluble components and alpha cellulose contents. However, it is highly recommended that such protozoicidal compounds should be isolated, purified and biochemically characterized in order to apply them as commercial products for the control of pest like termites, which cause a huge damage to woody plants, and their products. Keywords: Bark, sapwood, heartwood, Eucalyptus cammeldulensis , Dalbergia sissoo , Acacia arabica , termite flagellates

Evaluation of pre-hydrolyzed soda-AQ dissolving pulp from Populus deltoides using an ODED bleaching sequence

In the present work, the production of dissolving pulp from fast growing 30-year-old local plantation aspen was investigated. The mill-made chips of aspen (Populus deltoides) after being pre-hydrolyzed with water at 170 ºC, were pulped with a soda-AQ pulping process at a kappa number of 15. It was further delignified to a kappa number of 9.2 using a single stage oxygen delignification and bleached with a D0ED1 bleaching sequence at different kappa factor. The pulp viscosity was increased at higher brightness and similar α-cellulose when the kappa factor was increased from 0.30 to 0.45 in the D0 stage of the D0ED1 bleaching sequence, due to higher lignin dissolution and more fiber purification. The results showed that pre-hydrolyzed soda-AQ dissolving pulp can be made from Populus deltoides at a high level of alpha-cellulose content and acceptable levels of brightness and viscosity by means of proper control and optimization of pre-hydrolysis, pulping, and oxygen pretreatment conditions, and an optimized DED bleaching sequence.

Recycling of valueless paper dust to a low grade cellulose acetate: Effect of pretreatments on acetylation

The feasibility of the production of cellulose acetate (CA) from recycled paper dust from carton boxes was examined. Two pre-treatments were carried out on the carton box’s paper dust (CPD) to improve the pulp properties for better effect of synthesis. The results showed that the acid and oxygen-alkaline pretreatments were capable of increasing the alpha-cellulose content from 80.5 percent to 87.3 percent and 85.3 percent, respectively. Both pre-treatments also decreased the hemicellulose and ash contents by more than 50 percent. The degree of substitution (DS) of the resultant CA from pre-treated paper dust was improved from 1.94 to 2.13-2.16. The CA that was synthesized from the recycled paper dust showed comparable DS and had a similar trend of Fourier Transform Infrared (FTIR) spectra. Both pretreated pulps also showed an increment in the degree of crystallinity and had maximum degradation effect of temperature when compared to CPD CA. However, all the cellulose acetates produced showed a lower DS and thermal stability compared to commercial cellulose acetate (C CA). The degree of crystallinity of all the cellulose acetate was decreased in comparison to the original material.

Cellulose Purified by an Efficient and Environmental Friendly Method for the Production of NCC

In this study, cellulose extracted from Eucalyptus by ethanol, formic acid and catalyst MIK was used for nano crystal cellulose (NCC) production. The main function of MIK was to protect the structure of cellulose. Kappa numbers, holocellulose and alpha-cellulose contents of the obtained cellulose were calculated and the results showed that this cellulose provided an effective source for NCC. NCC from this material was characterized by Fourier transform infrared, X-ray diffraction and thermogravimetric analysis.

Determination of Holocellulose and Alpha-Cellulose Contents in Triploid Clones of <i>Populus tomentosa</i> Using NIRS

The aim of this work was to study the ability of NIR spectroscopy to determine holocellulose and alpha-cellulose contents in triploid clones of Populus tomentosa. For this purpose 90 trees with five families in different planting density grown in Shandong were analyzed. Calibration models were developed from wet chemical and NIR data using partial least squares (PLS) regression. High coefficients of determination (R2) and low root mean square errors of cross-validation (RMSECV) were obtained for holocellulose (R2 = 0.7805, RMSECV =0.652) and alpha-cellulose (R2 = 0.8702, RMSECV = 0.548) from wood meal. Prediction produced high correlation coefficients between laboratory and predicted values for holocellulose and alpha-cellulose contents, which R2 values are 0.7467 and 0.8505, and RMSEP are 0.993 and 0.553, respectively. This study showed that NIR analysis can be reliably used to predict holocellulose and alpha-cellulose contents in triploid clones of Populus tomentosa.

Prediction of the Crystallinity of White Pine Using near Infrared Spectroscopy

The crystallinity of wood is an important property of wood materials, it has an important effect on the physical, mechanical and chemical properties of cellulose fibers such as MOR, density, hardness increase, alpha-cellulose content, dimensional stability, moisture regain and dye sorption, chemical reactivity etc. The aims of this study were to investigate the ability of near infrared spectroscopy (NIR) to predict the crystallinity of white pine wood and the effect of spectra pretreatment on the prediction of crystallinity using NIR. Spectra were collected from wood powder a slowly rotating turntable and the crystallinity of wood was determined by X-ray diffractmeter (XRD) in this experiment. The results showed that NIR coupled with partial least square (PLS) method could be correlated with the crystallinity of white pine wood, and the ability of NIR prediction based on first derivative spectra was better than based on raw spectra or second derivative pretreated spectra. There was a significant correlation between NIR spectra and XRD determined crystallinity. The correlation coefficient for calibration (RC) was 0.932; the mean square error of calibration (RMSEC) was 0.022; the correlation coefficient for validation (RV) was 0.911; the mean square error of calibration (RMSEV) was 0.023. It was proved that NIR can rapidly and accurately predict white pine wood crystallinity.

Cotton Linters: An Alternative Cellulosic Raw Material

Cellulose in fibrous or in chemically modified form plays a relevant part in products for industrial applications and in products which are used in human daily life. Besides wood, cotton is an important natural source for cellulose. Linters are a by-product of the oil mills. The position of the linters in the technology of cotton is explained. in linters bleaching plant, the raw linters are purified mechanically and chemically. The principle of this process is shown. The resulting bleached linters (cotton linters pulp, CLP/cotton linters cellulose, CLC) have an alpha-cellulose content of about 99%. Due to their purity and to their properties, the cotton linters pulp is the cellulosic basis for a large number of special and niche products in the paper and chemical industry.

Applied study of birch pulp bleaching using dimethyldioxirane to obtain acetate-grade pulp

As a pulp bleaching agent, dimethyldioxirane (DMD) is effective and selective. In this study, it was employed as a delignifying agent or as an activating agent for hydrogen peroxide treatment in bleaching acetate-grade pulp. Brightness, kappa number, degree of polymerization (DP), and alpha-cellulose content were evaluated to determine the optimal charges of DMD: 2.5% AO, and 4% HSO5-, respectively. Results from the totally chlorine-free (TCF) sequences MEQMPA, MEpQMPA, and OQMPA suggested that DMD is both effective and selective as a delignifying agent but not as a brightening agent as compared to oxygen. And in a long sequence for the bleaching of dissolving pulp, acid treatment can be used in two approaches: to remove the metal ions without washing before the chelation stage, and to reduce hemicellulose and ash in the final stage.