scholarly journals THE CONVERSION OF THE MOISTURE-STABILITY WASTE-PAPERS WITH POLYMERIC COVERING. 2. CHAR-ACTERISTIC OF THE WASTE PAPER

2020 ◽  
pp. 365-371
Author(s):  
Yuriy Davydovich Alashkevich ◽  
Robert Zus'evich Pen ◽  
Natal'ya Viktorovna Karetnikova ◽  
Larisa Valer'yevna Chendylova ◽  
Viktor Anatol'yevich Kozhukhov ◽  
...  
Keyword(s):  
Cell Wall ◽  
Strength Properties ◽  
Waste Paper ◽  
Chemical Processing ◽  
Sodium Persulfate ◽  
Dry Grind ◽  
Thermochemical Processing ◽  
Higher Temperature ◽  
Moisture Stability ◽  
Cooking Liquor

Influence of the thermochemical processing (the cook) conditions and of the milling on characteristic of the waste paper with polyurethan and polyaziridin was studied. The waste paper was  reduced to the degree size of the particles 5...8 mm in mill of the dry grind and chemical processing under higher temperature (to 70 °C) by solution, contain sodium persulfate and hydroxide; duty of water 6. Duration of cook varied from 1 to 5 hours, expense of persulfate sodium varied from 2 to 12%, hydroxide sodium – from 0.5 to 3% from mass of the waste-papers.  The secondary fiber was obtaining by breaking-up of the pulp in the hydropulper.  The dependency of the length and factor of the form of the secondary fiber from conditions cook was absent. The slight width increasing of the fibers with the higher pH of cooking liquor was determined: from 26.5 мкм under pH 3–4 to 29 мкм under pH 8–9. The conjectural reason is swelling of the cell wall. The waste paper milling was executed in the «stream-barrier» machine. The strength properties of the paper correspond with the feature, inherent of the secondary pulp.

scholarly journals THE CONVERSION OF THE MOISTURE-STABILITY WASTE-PAPERS WITH POLYMERIC COVERING. 1. BREAK-ING-UP OF THE WASTE-PAPER

2019 ◽  
pp. 399-405
Author(s):  
Yuriy Davidovich Alashkevich ◽  
Robert Zus'evich Pen ◽  
Natalya Viktorovna Karetnikova ◽  
Larisa Valer'evna Chendylova
Keyword(s):  
Acid Medium ◽  
Waste Paper ◽  
Chemical Processing ◽  
Regression Equations ◽  
Sodium Persulfate ◽  
Dry Grind ◽  
Graphic Presentation ◽  
Higher Temperature ◽  
Moisture Stability ◽  
Sodium Consumption

Breaking-up of waste-paper with polyurethan and polyaziridin was studied. Paper moisture-stability is 49–51%. The waste paper reduced to the degree size of the particles 5–8 mm in the dry grind mill and chemical processing under higher temperature (to 70 °C) by sodium persulfate and hydroxide solution; duty of water 6. Cooking duration varied from 1 to 5 hours, solution strength of persulfate sodium – from 2 to 12%, hydroxide sodium – from 0.5 to 3% from the mass of bone-dry waste-paper. The secondary fiber received by breaking-up of the pulp in the hydropulper. The dependency degree of breaking-up, losses of the cellulose and liquor pH from the cooking variable factors approximated by the regression equations of the second order, which used for graphic presentation results. At the most importance of the all variable factors the cooks ended in the acid medium with pH 3 under practically full persulfate and hydroxide sodium consumption; at that the degree of the breaking-up more than 80% was reached, losses of the cellulose under the all conditions remained within the range of 12.6–14.6%. The necessary operations of the breaking-up: crush the dry waste-paper; the cooking of the waste-paper with sodium persulfate and hydrate; breaking-ap of the waste-paper in the hydropulper; washing the stringy mass by water; the hydrodynamic milling.

Optimization of chemical and enzymatic deinking of photocopier waste paper

BioResources ◽  
2010 ◽  
Vol 6 (1) ◽  
pp. 447-463 ◽  
Author(s):  
Puneet Pathak ◽  
Nishi K. Bhardwaj ◽  
Ajay K. Singh
Keyword(s):  
Physical Properties ◽  
Removal Efficiency ◽  
Strength Properties ◽  
Waste Paper ◽  
Cellulase Enzyme ◽  
Tensile Index ◽  
Drainage Time ◽  
Tear Index ◽  
The World ◽  
Better Than

The utilization of post-consumer papers in the production of new paper products is increasing all over the world in recent years. Recycling of photocopier paper is a major problem due to difficulty in removal of non-impact ink. Enzymes offer potential advantages in ecofriendly deinking of recovered paper. In this study the deinking of photocopier paper was examined using chemicals and a commercial cellulase enzyme. Parameters of deinking experiments were optimized for hydrapulping. The ink was removed by flotation and washing processes. Then these parameters were compared in terms of ink removal ability of the process, as well as optical and strength properties of the deinked paper. The application of enzymatic deinking improved ink removal efficiency by 24.6% and freeness by 21.6% with a reduction in drainage time of 11.5% in comparison to those obtained with chemical deinking. The physical properties, namely burst index and tensile index, were observed to improve by 15.3% and 2.7%, respectively and brightness and tear index decreased by 2.1% and 21.9%, respectively. Results of deinking efficiency of photocopier paper showed that the enzyme used in the present work performed better than the conventional chemicals used for deinking.

A Review: Natural Fiber as Reinforcement in Waste Paper Recycling and its Processing Methods

2013 ◽  
Vol 315 ◽  
pp. 443-447 ◽  
Author(s):  
S.K.A. Saferi ◽  
Y. Yusof
Keyword(s):  
Natural Fiber ◽  
Natural Fibers ◽  
Strength Properties ◽  
Hibiscus Cannabinus ◽  
Waste Paper ◽  
Kenaf Fiber ◽  
Healthy Environment ◽  
Wide Range ◽  
Increased Strength ◽  
The Right

As demand for clean and healthy environment, people make many alternate solutions to save the environment. To save trees and overcome landfill of waste material and waste disposal by burning activities issues (cause to losing energy and increase pollution), people nowadays take recycling as a recovery. Recycling waste paper into new product increased over the years. Shortage of wood supply required new sources of natural fiber for papermaking industry. Many researchers have studied new sources of natural fibers from non wood materials, such as oil palm residues, kenaf (Hibiscus Cannabinus), pineapple leaf, banana, and coconut fiber. Kenaf is choose as reinforcement agent for recycled waste paper to maximize the use of kenaf in industry application due its wide range of advantages where pineapple leaf are choose as reinforcement agent because abundantly of these material in Malaysia. Reinforcement of natural fiber into waste paper during recycling process expected to increased strength properties of final product. To understand the right and suitable processing method for kenaf fiber and pineapple leaf leaves previous work from other researchers are studied to investigate pulping procedure of natural fiber and its effect on mechanical strength.

scholarly journals Climate, nitrogen and grass. 4. The influence of age on chemical composition and in vitro digestibility of maize (Zea mays L.) and tall fescue (Festuca arundinacea Schreb.).

1971 ◽  
Vol 19 (4) ◽  
pp. 264-272 ◽  
Author(s):  
B. Deinum ◽  
J.G.P. Dirven
Keyword(s):  
Cell Wall ◽  
Zea Mays ◽  
Chemical Composition ◽  
Tall Fescue ◽  
Festuca Arundinacea ◽  
Zea Mays L ◽  
In Vitro Digestibility ◽  
Higher Temperature ◽  
Effect Of Age

In a field experiment with maize it was found that in vitro digestibility of leaves decreased somewhat during undisturbed growth, whereas digestibility of stems decreased appreciably. This decrease in leaf digestibility was caused by a lower digestibility of later-developed leaves and by a slight decrease in digestibility during ageing of each individual leaf. In a pot experiment with tall fescue grown at 15/10, 20/15 and 25/20 deg C, it was found that a higher temperature resulted in higher concentrations of cell-wall constituents and lower digestibility, whereas during ageing the percentage of cell-wall constituents remained constant or even decreased, digestibility decreasing slightly. Results suggested that in a constant climate the effect of age on digestibility would be small, and that the great effect of age on forage quality in spring is mainly due to rising temperature and stem formation. (Abstract retrieved from CAB Abstracts by CABI’s permission)

scholarly journals Cell Wall Core Galactofuran Synthesis Is Essential for Growth of Mycobacteria

2001 ◽  
Vol 183 (13) ◽  
pp. 3991-3998 ◽  
Author(s):  
Fei Pan ◽  
Mary Jackson ◽  
Yufang Ma ◽  
Michael McNeil
Keyword(s):  
Cell Wall ◽  
Mycobacterium Smegmatis ◽  
Mycolic Acid ◽  
Separate Experiment ◽  
Temperature Sensitive ◽  
Origin Of Replication ◽  
Knockout Mutant ◽  
Allelic Replacement ◽  
Higher Temperature ◽  
Mycobacterial Cell Wall

ABSTRACT The mycobacterial cell wall core consists of an outer lipid (mycolic acid) layer attached to peptidoglycan via a galactofuranosyl-containing polysaccharide, arabinogalactan. This structural arrangement strongly suggests that galactofuranosyl residues are essential for the growth and viability of mycobacteria. Galactofuranosyl residues are formed in nature by a ring contraction of UDP-galactopyranose to UDP-galactofuranose catalyzed by the enzyme UDP-galactopyranose mutase (Glf). In Mycobacterium tuberculosis the glf gene overlaps, by 1 nucleotide, a gene, Rv3808c, that has been shown to encode a galactofuranosyl transferase. We demonstrate here thatglf can be knocked out in Mycobacterium smegmatis by allelic replacement only in the presence of two rescue plasmids carrying functional copies of glf and Rv3808c. The glf rescue plasmid was designed with a temperature-sensitive origin of replication and the M. smegmatis glf knockout mutant is unable to grow at the higher temperature at which the glf-containing rescue plasmid is lost. In a separate experiment, the Rv3808c rescue plasmid was designed with a temperature-sensitive origin of replication and theglf-bearing plasmid was designed with a normal original of replication; this strain was also unable to grow at the nonpermissive temperature. Thus, both glf and Rv3808c are essential for growth. These findings and the fact that galactofuranosyl residues are not found in humans supports the development of UDP-galactopyranose mutase and galactofuranosyl transferase as important targets for the development of new antituberculosis drugs.

scholarly journals Methods of Chemical and Thermochemical Processing of Hydrolytic Lignin

2021 ◽  
pp. 263-275
Author(s):  
Irina G. Sudakova ◽  
Alexander V. Levdansky ◽  
Boris N. Kuznetsov
Keyword(s):  
Porous Carbon ◽  
Oil And Gas ◽  
Carbon Materials ◽  
Strength Characteristics ◽  
Organic Fertilizers ◽  
Original Form ◽  
Chemical Processing ◽  
Organic Products ◽  
Hydrolytic Lignin ◽  
Thermochemical Processing

The analysis of the latest publications on the use of hydrolytic lignin, which is a large-tonnage waste of wood chemical processing, was carried out. In its original form, the hydrolytic lignin is used as fuel, fuel briquettes and pellets, binders and adhesives, organic fertilizers, fillers and enterosorbents. The processing of hydrolytic lignin by chemical and thermochemical methods allows to significantly expand the range of valuable products obtained from it. They are used in chemical, oil and gas and construction industries, metallurgy and other areas. Hydrolytic lignin is most widely used for the production of carbon sorbents. Recently, methods of thermochemical processing of lignin into porous carbon materials with the required texture and strength characteristics as well as into valuable organic products have been developed

scholarly journals Identification of bacteria involved in the decomposition of lignocellulosic biomass treated with cow rumen fluid by metagenomic analysis

2019 ◽  
Author(s):  
Chol Gyu Lee ◽  
Yasunori Baba ◽  
Ryoki Asano ◽  
Yasuhiro Fukuda ◽  
Chika Tada ◽  
...  
Keyword(s):  
Cell Wall ◽  
Plant Cell Wall ◽  
Plant Biomass ◽  
Rumen Fluid ◽  
Waste Paper ◽  
Metagenomic Analysis ◽  
Fluid Systems ◽  
Genes Encoding ◽  
Identification Of Bacteria

AbstractPreviously, pretreatment of plant biomass using rumen fluid systems was developed to decompose cell wall. However, microbes which involved in plant cell wall decomposition in this system have not been identified, because the conditions of this system are different from the in situ rumen environment. We investigated the bacteria involved in the decomposition of cellulose and hemicellulose in a waste paper with the rumen pretreatment system using shotgun metagenomic analysis with next generation sequencing. After pretreatment of waste paper, about a half of the cellulose and hemicellulose content was decomposed. Genes encoding for cellulase and hemicellulase were mainly found to belonging to Ruminococcus, Clostridium, and Exiguobacterium. This study shows that Clostridium and Exiguobacterium, which have not been identified as predominant genus involved in cellulose and hemicellulose decomposition, might be categorized as the main fibrolytic bacteria in this system.

Monotonic Strength Properties of Siberian Yellow Pine

2008 ◽  
Vol 599 ◽  
pp. 137-142
Author(s):  
Pentti O. Kettunen ◽  
Taina Vuoristo ◽  
Terho Kaasalainen
Keyword(s):  
Cell Wall ◽  
Shear Strength ◽  
Cell Structure ◽  
Middle Layer ◽  
Axial Direction ◽  
Tangential Direction ◽  
Strength Properties ◽  
Yellow Pine ◽  
The Difference ◽  
Normal Strength

Strength values of the sapwood of Siberian yellow pine were measured in a system with orthogonal coordinates along the axial, radial, and tangential directions of the cell structure. Highest strength was the axial normal strength and lowest the tangential normal strength. The difference between these two values was 87-fold. Shear strength values remained between the two normal strength values. The highest shear strength appeared in tangential direction across the reinforcing fibers, i.e., on the plane perpendicular to the axial direction. Lowest shear strength appeared in tangential direction on the plane perpendicular to radial direction. The variations are due to orientation of cells and of fiber reinforcement in the cell wall laminas, especially in the middle layer of the secondary cell wall.

Dynamic strength properties and structural integrity of wood modified with cyclic N-methylol and N-methyl compounds

Holzforschung ◽  
2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Lukas Emmerich ◽  
Christian Brischke ◽  
Susanne Bollmus ◽  
Holger Militz
Keyword(s):  
Cell Wall ◽  
Structural Integrity ◽  
Bending Strength ◽  
Cold Water ◽  
Impact Resistance ◽  
Dynamic Strength ◽  
Strength Properties ◽  
Significant Loss ◽  
Solid Content ◽  
Water Leaching

Abstract Cyclic N-methylol compounds have been used for cell wall impregnation modifications of wood. Besides an improved decay resistance and dimensional stability, the modifications resulted in a decrease of wood’s dynamic strength properties. However, the mechanisms behind a significant loss in dynamic strength are not fully understood yet. In this study, wood blocks were treated with the N-methylol compounds 1,3-dimethylol-4,5-dihydroxyethyleneurea (DMDHEU) and methylated DMDHEU (mDMDHEU) and the N-methyl compound 1,3-dimethyl-4,5-dihydroxy-ethyleneurea (DMeDHEU). In order to study the factors that control the changes of wood performance under dynamic loads, single (impact bending strength, IBS) and multiple dynamic impact (resistance to impact milling, RIM) tests were applied. It became evident, that reductions in IBS and RIM increased with increasing solid content, formaldehyde content and catalyst concentration of the impregnation solutions, but were not affected by a cold-water leaching. Differences in structural integrity of wood modified with N-methylol and N-methyl compounds were more pronounced than those of IBS. Therefore, RIM appeared more sensitive to changes on cellular level, as a higher degree of co-condensation of the N-methylol compounds with cell wall polymers was expected in comparison with the N-methyl compound.

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