Research Paper
Chemical conversion
Fatemeh Jadidyan; Mohammad Talaeipoor; Saeed Mahdavi; Amirhoman Hamasi
Abstract
The purpose of this study is the evaluation of bagasse pith for heating energy and activated carbon production. To assess the energy production of the pith, bulk density, melting point, and heating value were measured. Furthermore, percentage of moisture, ash, volatile compounds, fixed carbon, lignin, ...
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The purpose of this study is the evaluation of bagasse pith for heating energy and activated carbon production. To assess the energy production of the pith, bulk density, melting point, and heating value were measured. Furthermore, percentage of moisture, ash, volatile compounds, fixed carbon, lignin, and elements contents were determined. Ash and volatile content average were measured at 30.23% and 67.14%, respectively. The bulk density average of the pith powder with 80 meshes was determined at 0.15 g/cm3. Lignin content and melting point of pith is measured 23.1%, and 1050 °C, respectively. Sulfur content is important in terms of environmental pollution and it was determined 0.3%. Gross heating value was measured directly by calorimeter bomb to 10.30 MJ/kg that is lower than bagasse and wood. The activated carbon produced from pyrolysis of bagasse pith was chemically activated with zinc chloride. The chemically activated carbons were characterized by measuring iodine of 504 mg/g, specific surface (BET) of 478 m2/g, and pore diameter of 7.45 nanometer. It is suitable for liquid absorption according to the pore size.
Research Paper
Composite wood products
Abolfazl Kargarfard; Amir Nourbakhsh
Abstract
AbstractThe objective of the present study was the utilization of cotton stalk residues for medium density fiberboard production. MDF was produced applying Three press temperatures (170, 180, and 190 oC ) and three pressing times (3,4 and 5 minutes) were used to produce medium density fiberboard (MDF) ...
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AbstractThe objective of the present study was the utilization of cotton stalk residues for medium density fiberboard production. MDF was produced applying Three press temperatures (170, 180, and 190 oC ) and three pressing times (3,4 and 5 minutes) were used to produce medium density fiberboard (MDF) from cotton stalks fibers. The properties of the laboratory boards were measured and the results are analyzed applying factorial experiment and randomized design. In case, the statistical difference was observed between the averages, then Duncan Multiple Range Test was used for grouping the averages. The results showed that as either press temperature or press time is increased, the modulus of rupture of the of the boards was significantly improved and the highest value was reached when 190 oC press temperature and 5 minutes press time was applied. The internal bonding of the boards was significantly higher when 180 oC press temperature was applied. The effect of press temperature on thickness swelling after 2 and 24 hours immersion in water was statistically significant and the lowest values were obtained when 190 oC press temperature was used. The results of this study indicated that the cotton stalks can be considered as a potential raw material for medium density fiberboard production and the properties of the boards meets the EN requirements.
Research Paper
Pulp and paper
Ahmad reza Saraeyan; Somayeh Heidari; Ahmad reza Shakeri
Abstract
Increased environmental concerns over the use of certain synthtic packaging in combination with consumer demands led to increased interest in alternative packaging materials research. Paper is biodegradable and widely used in packaging applications therefore perfectly safe for the environment. In an ...
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Increased environmental concerns over the use of certain synthtic packaging in combination with consumer demands led to increased interest in alternative packaging materials research. Paper is biodegradable and widely used in packaging applications therefore perfectly safe for the environment. In an effort to produce more environmentally friendly materials, renewable and biodegradable biopolymers have been utilized as paper coating substances. in this study carried out to determine effect of the four type of biopolymers such as anionic starch, chitosan, polyvinyl alcohol and etylenvinyl alcohol, on the smoothness, Water absorption, air resistance, burst Index properties paper made of bagasse soda pulp. Coating done whith coater tester. Coating weight was 3-6 g/m2. The results of the mechanical and physical properties of the handsheets showed that, led to increase index burst handsheets coated with etylenvinyl alcohol and anionic starch indices as 34.4 and 26.26% compared to control sample. Air resistance and smoothness was for coated paper with starch more than control sample indices as 173.23 and 18.73%. also coated paper with chitosan showed minimum value..
Research Paper
Management and Economics wood
Neda Esmaeeli; Maryam Ghorbani; pourya biparva
Abstract
This research was conducted to determine the optimal conditions for chemical modification of poplar wood with glutaraldehyde and its effect on the physical properties of products. Test samples were prepared according to the standard ASTM-D1037 and impregnated in the laboratory cylinders with Glutaraldehyde ...
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This research was conducted to determine the optimal conditions for chemical modification of poplar wood with glutaraldehyde and its effect on the physical properties of products. Test samples were prepared according to the standard ASTM-D1037 and impregnated in the laboratory cylinders with Glutaraldehyde at a concentration of 10% by using vacuum-pressure method. Modification reaction was done in two procedure. Heating first in the laboratory cylinder (Hydrothermal) for 4 hour and second in oven for 4 level 4,12,24,48 and 48hours. Weight percent gain of modified by hydrothermal and oven method was measured 2.10, 9.26, 10.02, 11.40 and 14.15% respectively. Chemical modification with glutaraldehyde by hydroxyl group's substitution, reduced the uptake of water and swelling of poplar wood. So that at the end of soaking in water the heating in the oven for 48 hours with minimum water absorption and dimensional changes in the 57.32 and 12.08 respectively, and highest bulking, ASE and ASE′ in 8.31,67 and 35.51% respectively was selected as the optimal level. This improvement compared to other modification levels demonstrates the forming of permanent Cross-linking of acetal that increased by Prolongation of the heating time.
Research Paper
Pulp and paper
Sahba Aliniyay Lakani; Elyas Afra; Hossein Yousefi
Abstract
In this research, nano fibrillated cellulose, as a reinforcement nano material and environmentally biodegradable material which has recently attracted the attention of most researchers and paper producers, has been added to chemi-mechanical pulp used for manufacturing of liner board at different charges ...
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In this research, nano fibrillated cellulose, as a reinforcement nano material and environmentally biodegradable material which has recently attracted the attention of most researchers and paper producers, has been added to chemi-mechanical pulp used for manufacturing of liner board at different charges of 5, 20, 50 and 100% in two different levels of freeness. Also, the effect of wet press, one of the the most important processing agents on the properties of paper reinforced with nano fibrillated cellulose, in two levels of press pressure which included 3 and 6 bar, has been investigated. Finally, physical, barrier and strength properties of the papers produced have been measured according to TAPPI test methods. Addition of nano fibrillated cellulose was resulted in improved tensile and air resistance of chemi-mechanical pulp and increasing trend in improving of these properties with increase in press pressure was one of the important achievements of the present research.
Research Paper
Physics and anatomy
Nooshin Toghraie
Abstract
One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 ...
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One-year seedlings of five species of eucalypt: E. camaldulensis, E. microtheca, E. viminalis, E. globulus and E. gunnii were treated for 14 weeks in growth season, tilting a branch to c. 60° in every successful ones. We investigated the anatomical features of stems wood after 15 days and every 2 weeks according to IAWA list of features afterwards.The results showed that tilted stems formed more tension wood in the form of gelatinous fibers than straight (untreated) ones. The formation of gelatinous fibers was considered to be closely related to tension wood formation. The formation of gelatinous fibers was considered to be closely related to tension wood formation. Excluding E. globulus, all the other species formed growth eccentricity and tension wood. Although the significant differences between the species and between different locations in the branches, there were no significant differences between the percent of tension wood among the species studied.
Research Paper
Mechanical conversion of wood and wooden fittings
Mohammad Ghofrani; Zahra Mohammad Moradi; Saeed Khojasteh Khosro
Abstract
In present study the effect of different methods of applying transparent coatings on adhesion strength of coating in Walnut (Juglans regia), Maple (Acer velutinum) and Pine (Pinus eldarica) species was investigated. For this purpose, samples prepared with dimension of 200×100×20 mm and 8% ...
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In present study the effect of different methods of applying transparent coatings on adhesion strength of coating in Walnut (Juglans regia), Maple (Acer velutinum) and Pine (Pinus eldarica) species was investigated. For this purpose, samples prepared with dimension of 200×100×20 mm and 8% moisture content. Samples’ surfaces were sanded with 100, 120 and 180 grate sizes sandpaper significantly. Then after preparation wooden samples with sealer, their surfaces covered with clear and acid catalyzed transparent finish in separate process by using spray gun and applicator. Adhesion strength of coating was measured with Pull-Off method based on ASTM D4541 standard. Fluorescence microscopy test used for investigation coating penetration in spray gun and applicator method. Results showed that the method of applying coating on wooden surfaces has significantly affected adhesion strength, and highest adhesion strength between all samples, observed in samples coated with applicator method. Investigation of coating penetration indicated that applicator method had good penetration in wood substrate in comparison spray gun method. Highest differences in adhesion strength of coating between spray gun and applicator method were observed in Walnut and Maple’s samples. In general, highest adhesion strength of coating was found in Walnut samples covered with acid catalyzed transparent finish by using applicator method.
Research Paper
Pulp and paper
Farhad Zeinaly; Ahmad Reza Saraeian; Mohammadhadi Aryaei monfared; Ali Kazemi Tabrizi
Abstract
In conducting environmentally friendly processes for pulp production, first step is to reduce the effluent pollution load in each stage, and because the bleaching process is the most polluting stage in the production of pulp, improving it is one of the most important matters. The first act to ameliorate ...
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In conducting environmentally friendly processes for pulp production, first step is to reduce the effluent pollution load in each stage, and because the bleaching process is the most polluting stage in the production of pulp, improving it is one of the most important matters. The first act to ameliorate bleaching process of chemical pulps is the reduction of colored materials, mostly lignin, which enter to the bleaching section. Thus, the use of oxygen delignification stage after pulping and before bleaching process is the key stage in improving process and cleaner production. In this study, the effect of conducting oxygen-delignifying treatment by two kinds of machines, and under different process condition, on chemical, physical, mechanical and optical properties of bagasse soda pulp was investigated. The bagasse soda pulp with the kappa number of 20, 955 ml/g viscosity, and 37% ISO brightness was prepared from Pars Hafttapeh Company. Oxygen-delignifying treatments were carried out with three different temperatures of 90, 100 and 110°C, and two oxygen pressures of 5 and 7 bars, with and without magnesium sulfate addition, by two kinds of machines. Results indicated that oxygen delignification treatment led to intense decrease in pulp kappa number, while the pulp viscosity did not change. Results of measuring delignified pulp viscosity showed that the magnesium sulfate addition caused to prevention of pulp viscosity downfall. The increase in reaction temperature had a significant effect on the process improvement, but raising the oxygen pressure did not have a meaningful effect on the process. The pulp brightness was increased about 4-6%. And also, due to the need of shorter time in order to reach the reaction temperature in the Iranian made machine, pulp delignifying by this machine was a little lower than Quantum machine.
Research Paper
Composite wood products
ghasem asadpour; seyyed majid zabihzadeh; Maryam Ghorbani; mahmoud davoudi
Abstract
Current research was conducted to investigate the effect of thermal modification on practical properties of horn beam bark flour-polypropylene composites. Wood plastic composites were divided in two levels of control and thermal modification, both levels included of 4 groups in bark fillers; 10, 20, ...
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Current research was conducted to investigate the effect of thermal modification on practical properties of horn beam bark flour-polypropylene composites. Wood plastic composites were divided in two levels of control and thermal modification, both levels included of 4 groups in bark fillers; 10, 20, 30 and 40%. Test samples prepared with maleic anhydride-grafted polypropylene as coupling agent by injection molding method. According to the results, bark flour increased water absorption, tensile and bending modulus. High proportion of bark fillers declined mechanical strength. Thermal modification significantly improved physical and mechanical properties of composite. Using lignocellulosic material flour bark hornbeam, tensile modulus and flexural modulus of composite material background had the highest improvement. In comparison between mechanical properties, impact resistance by adding flour bark had the greatest decrease. Thermal modification by increasing the crystallity, hemicellulose degradation, loss of polarity, increased compatibility between the two phases and uniform distribution of bark fillers in polymers, increased mechanical resistance.
Research Paper
Management and Economics wood
Hamed Ahmadi; Ajang Tajdini; Amir Lashgari
Abstract
In this research, the impact of various products design was investigated in end-customer’s satisfaction. . For this purpose, the variables are: products ‘external characteristic variables, quality, price, distributing system, after sales services, perceived value and sex moderator variable. ...
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In this research, the impact of various products design was investigated in end-customer’s satisfaction. . For this purpose, the variables are: products ‘external characteristic variables, quality, price, distributing system, after sales services, perceived value and sex moderator variable. The statistical population of this research includes all the consumers of household wooden steel furniture in Tehran city. In order to evaluate and examine the conceptual model, structural equation method and AMOS software are used. The results showed that the model has been fitted in the first-grade and second-grade measurement models and also on structural model. In measurement model, the measurement indices have created some meaningful factor loadings. This issue shows that model has been determined from theoretical literature and the criteria of this measurement have been recognized correctly. This caused a high validity of the measurements ‘tools. The variables of external characteristics, quality, price, after -sales services and perceived value are all effective at 99 percent of the confidence level on the consumer of household wooden furniture. But, the effect of distributing system variable on customer satisfaction did not accept. Also according to the obtained results, it is clear that sex variable can just adapt the relationship between external characteristics and customer satisfaction in the level of 90 percent significance.
Research Paper
Management and Economics wood
Reza Oladi
Abstract
One of the main reasons for low treatability of pine wood is pit aspiration during drying in free water domain or heartwood formation. In this research, for opening the aspirated pits in heartwood of loblolly Pine (Pinus taeda), biological incising modification method with bacteria was used and the impacts ...
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One of the main reasons for low treatability of pine wood is pit aspiration during drying in free water domain or heartwood formation. In this research, for opening the aspirated pits in heartwood of loblolly Pine (Pinus taeda), biological incising modification method with bacteria was used and the impacts of different environments and strains of bacteria on the wood gas permeability were studied. Several famous and known strains of Bacillus subtilis UT B96 bacteria in collection of plant protection department of University of Tehran (22, 35, 40, and 96) were supplied in two different culture media of bacteria, namely Nutrient Broth and water bacteria solution. Optical microscopy was used to figure out the qualitative bacterial effect on the tracheid pit pairs. Data analysis revealed that bacteria strain no.22 and water bacteria solution are the most suitable selections to open the aspirated pits and improve the wood permeability. The more destructive effect of the best strain of bacteria may be due to its ability to produce more degrading enzyme. The higher impact of bacteria in the aquatic environment is probably due to their easier mobility, limited access to oxygen or lack of access to an alternative food.
Research Paper
Composite wood products
mowhammad madadi; Amir Nourbakhsh
Abstract
AbstractIn this research, utilization of ZnO nanoparticles and eggshell powder on physical and mechanical properties of polypropylene/wood flour composite were investigated. For this purpose, wood flour and polypropylene was mixed at 60 to 40% by weight. Eggshell powder at three levels (0, 5 and 10) ...
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AbstractIn this research, utilization of ZnO nanoparticles and eggshell powder on physical and mechanical properties of polypropylene/wood flour composite were investigated. For this purpose, wood flour and polypropylene was mixed at 60 to 40% by weight. Eggshell powder at three levels (0, 5 and 10) percent and nano ZnO at four levels (0, 1.5, 3 and 5) percent were considered as variable factors. Physical and mechanical properties including water absorption and thickness swelling after 2 and 24 hours immersion in water, flexural strength were measured in accordance with DIN-EN 310-2006 standard, and tensile strength were measured in accordance with ASTM D1037 standard. Scanning electron microscope (SEM) were performed to interpret the results. The results were statistically analyzed using factorial experimental under completely randomized block design and the averages were compared using DMRT. Results showed that increasing the mixing ratio of eggshell powder to wood flour decrease mechanical strengths but were improved in water absorption and thickness swelling after 2 and 24 hrs. Using 1.5% nano zno increased the strength properties to the maximum values and improved physical properties.
Research Paper
Composite wood products
Hossein Rangavar; Abolfazl Kargarfard; Mohammad saleh Hosseini fard
Abstract
In this study, the effect of type II and III Portland cement and the use of undepithed and depithed sunflower stalks particles (Helianthus Annuus) with percentages of different mixing ratio of the poplar wood particles (Populous alba) with 100:0, 75:25, 50:50, 25:75 and 0:100 respectively in the manufacturing ...
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In this study, the effect of type II and III Portland cement and the use of undepithed and depithed sunflower stalks particles (Helianthus Annuus) with percentages of different mixing ratio of the poplar wood particles (Populous alba) with 100:0, 75:25, 50:50, 25:75 and 0:100 respectively in the manufacturing of wood-cement composites were studied. Physical and mechanical properties of boards were measured as the effect of lignocellulosic material (sunflower stalks andpoplar wood) and Portland cement type (II and III) on the cement setting time. The results of the study showed that the lignocellulosic material reduced the hydration reaction and increased cement setting time. In this regard, sunflower stalks particles in comparison with poplar wood particles increased cement setting time intensively. The boards made from type III Portland cement had better mechanical strength and physical properties (water absorption and thickness swelling reduced) than with type II Portland cement. In comparison with poplar wood particles usage, the use of sunflower stalks particles and more amount of it caused to mechanical properties decreases and increased the water absorption and thickness swelling after 2 and 24 h water immersion. Therefore the best characteristics were obtained in boards made from 100 percent poplar wood particles. In other hands, using depithed sunflower stalks particles caused to improved the physical and mechanical characteristics. In general, it can be concluded that 25 percent of depithed sunflower stalks particles relative to poplar wood particles (relative to mass lignocellulosic materials( with type III Portland cement in the manufactured wood-cement boards has suitable physical and mechanical properties for usage of these boards in interior building applications.
Research Paper
Pulp and paper
Ramin Veisi; Rabi Behroz; Iman Khajeh Ali
Abstract
This study and it aim was accomplished on the effect of ECF bleaching on optical and mechanical properties of bagasse soda pulp. For this purpose, some soda unbleached pulps were randomly selected from Pars mill. Then these pulps were bleached with OD(Ep)P and OD(Ep)D stages by oxygen, chlorine dioxide ...
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This study and it aim was accomplished on the effect of ECF bleaching on optical and mechanical properties of bagasse soda pulp. For this purpose, some soda unbleached pulps were randomly selected from Pars mill. Then these pulps were bleached with OD(Ep)P and OD(Ep)D stages by oxygen, chlorine dioxide and hydrogen peroxide. The hand sheets with 60 gr/m2 were prepared from soda unbleached and bleached from EH(control), OD(Ep)P and OD(Ep)D stages pulps, then the optical and mechanical properties were measured and compared according by using TAPPI Standard test methods. The results showed that residual lignin and kappa number decreased following above-mentioned of bleaching stages. The brightness, greenness and K/S ratio were increased in bagasse soda pulps by bleaching. In different treatments, the brightness, opacity, absorbance coefficient, burst, breaking length, tensile, tear strength sensible increased in OD(Ep)P and OD(Ep)D as compared with EH (control) mill bleaching stages. In general, first OD(Ep)P stage, then OD(Ep)D were better than EH (control) mill stage in more of were measured properties.
Research Paper
Management and Economics wood
Mohammad Ghofrani
Abstract
In this study, the effect of heat treatment of Alder (Alnus glutinosa), Poplar (Populus nigra) and Spruce (Picea abies) on adhesion strength of clear and acid catalyzed transparent coating was investigated. For this aim, wooden samples were prepared with dimension of 200×100×18 mm (longitudinal, ...
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In this study, the effect of heat treatment of Alder (Alnus glutinosa), Poplar (Populus nigra) and Spruce (Picea abies) on adhesion strength of clear and acid catalyzed transparent coating was investigated. For this aim, wooden samples were prepared with dimension of 200×100×18 mm (longitudinal, tangential, radial) from sapwood on tangential surface. Samples were kept under heat treatment in oven with 150 and 180˚C temperatures for about 3 hours. After treatment, samples’ surfaces were sanded with 120 and 180 grit size sand paper, respectively. Contact angle of water was measured before and after treatment. Samples’ surfaces were covered with a transparent coat in two separate processes which were clear and acid catalyzed. Adhesion strength of coating measured with Pull Off method according to ASTM D-4541 standards. Results showed that the heat treatment increased contact angle. This increase continues as the heat treatment temperature goes higher and it leads to decrease in wettability of samples’ surfaces. Results also indicated that heat treated of wood had significant effect on adhesion strength of coating. Adhesion strength in control samples was more than heat treated samples. lowest coating strength was observed in samples which were heat treated in 180 ˚C.
