Chemical conversion
Ramin Vaysi
Abstract
Background and aim: Every year, large amounts of species adapted to the semi-arid environment of Tehran planted. Meanwhile, planted plane tree (Platanus orientalis) and eldar pine (Pinus Halepensis var. Eldarica) tree in Tehran, in addition to creating a green and lively urban space, can also play a ...
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Background and aim: Every year, large amounts of species adapted to the semi-arid environment of Tehran planted. Meanwhile, planted plane tree (Platanus orientalis) and eldar pine (Pinus Halepensis var. Eldarica) tree in Tehran, in addition to creating a green and lively urban space, can also play a big role in absorbing heavy metals and components in the polluted air of Tehran. This study and it aim was accomplished on identification and comparison of the heavy metals in the wood, bark and leaves of planted plane tree and eldar pine tree by using flame atomic absorption method.Materials and methods: In this study, 20 separate test samples of leaves, wood, and bark of planted elder pine and plane tree were randomly selected from the 4th district of Tehran. According to the TAPPI standard tests, the leaf flour, wood and bark of the samples and their ash percentage were measured. Then with the help of 63% nitric acid and for one hour, the solution containing heavy metal was separated from the ash. In this research, atomic absorption spectrophotometer was used to determine the type and percentage of metal ions absorbed in the wood, bark and leaves of plane tree and eldar pine tree.Results: The results showed that the most ash was found in plane tree bark and the least in plane tree wood. The highest amount of iron ion absorption was found in plane tree leaves, while the lowest amount of iron ion absorption was found in plane tree wood. The amount of iron ion absorption in eldar pine bark is more than its wood and leaves and in oriental plane leaves is more than its wood and bark. The highest amount of potassium ion absorption was observed in eldar pine leaves and the lowest was in eldar pine bark. The amount of potassium ion absorption in eldar pine leaves was higher than its wood and bark, and in plane tree, bark is higher than its wood and leaves. In addition, the absorption of potassium ion is more in plane tree than in eldar pine. The highest amount of copper ion absorption was observed in eldar pine leaves and the lowest amount was observed in plane tree wood. The rate of absorption of copper ions in leaves is higher than the bark and wood of both species. In addition, the absorption of copper ions in eldar pine is more than that of plane tree. The highest amount of lead ion absorption was observed in the bark of eldar pine and the lowest amount was observed in plane tree and eldar pine wood. The amount of lead ion absorption in the bark was more than in the leaves of both species and in eldar pine was more than in plane tree. The highest amount of zinc ion absorption was found in oriental plant leaves and the least in oriental plant wood. The rate of absorption of zinc ions in the bark of eldar pine is more than its leaves and wood and in oriental plant leaves is more than its bark and wood. The highest amount of nickel ion absorption was found in plane tree and elder pine leaves and the lowest in oriental plant wood. The rate of absorption of nickel ions in oriental plant and eldar pine leaves is higher than in their bark and wood. In addition, between the two species, the rate of absorption of nickel ions in eldar pine is higher than that of plane tree.Conclusion: So that, the results showed that the leaves and bark of both species have a great role in the absorption of heavy metal in the air. In addition, the importance of the eldar pine species in absorbing heavy metal such as nickel, zinc, lead, iron and copper is more than the plantain species due to its evergreen nature. Eldar pine and plane tree wood showed the least importance in absorbing heavy metal. While the importance of bark in absorbing lead is the highest. In other words, in urban areas like Tehran, where air pollution is very important, planting eldar pine species seems to be more effective than plane tree.
Chemical conversion
Khadijeh Khorram Margavi; Noureddin Nazarnezhad; Seyd Majid Zabihzadeh
Abstract
Background and objectives: Contamination in pulp mill wastewater and subsequently surface and underground water sources contamination with heavy metals is one of the most important problems which threatens the health of human being and other creatures. These metals penetrate and pollute the soil and ...
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Background and objectives: Contamination in pulp mill wastewater and subsequently surface and underground water sources contamination with heavy metals is one of the most important problems which threatens the health of human being and other creatures. These metals penetrate and pollute the soil and water. In this regard, this study investigated and determined heavy metals in the pulp mill wastewater before and after the wastewater treatment process. In this study the newspaper adsorbent was prepared and the efficiency of the adsorbent in the adsorption of copper, lead and cadmium metals was studied.Methodology: The adsorption experiments were performed to investigate the effect of the time of contact of the newspaper adsorbent and metals, and dose of the adsorbent. For this purpose, waste newspapers were first treated with sodium bicarbonate for one hour and then refluxed with 5% disodium hydrogen phosphate for 4 hours at 100 degrees Celsius and finally washed. Aqueous solutions with an initial concentration of 30 ppm for three metals lead, copper and cadmium were prepared by diluting the standard solution with distilled water. A specific amount of adsorbent was added to 10 ml of each solution and stirred in a mechanical shaker for specific times. Then they were filtered by filter paper purified and analyzed by atomic absorption spectroscopic device. After drying, the solid phase of the wastewater sample was subjected to acid digestion with nitric acid at a ratio of one to five. Then, the digested samples were analyzed with an atomic absorption spectrometer after washing.Results: The results of wastewater analysis in the basins before and after treatment showed that the amount of lead, copper and cadmium in the wastewater before treatment were 0.2129, 0.5983 and 0.0004 ppm, respectively. The amount of metals after the treatment process was 0.0469, 0.134 and 0.0001 ppm for lead, copper and cadmium, respectively. Also, according to the results, taking into account that the absorption rate was high and the same in the amount of absorbent used and the treatment times; the amount and time of the desired treatment in this experiment were not effective factors in the amount of metal absorption. Conclusion: The newspaper adsorbent is a good adsorbent for removing heavy metals from aqueous solutions due to high absorption capacity and low cost, which make the newspaper a potential adsorbent for the removal and wastewater treatment of the heavy metals. According to the results, the dosage and time of treatment with the newspaper adsorbent were not effective factors in metal removal.
Chemical conversion
Zahra Daeepour; amir lashgari; Mehran Roohnia; Ahmad Jahan latibari; Vahid Safdari
Abstract
Background and objectives: Nowadays, the importance of treatments such as water washing and ethanol-acetone washing to improve the acoustic properties of wood has been noticed by the makers of musical instruments. Wood extractives are in the list of those materials that often do not have a construction ...
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Background and objectives: Nowadays, the importance of treatments such as water washing and ethanol-acetone washing to improve the acoustic properties of wood has been noticed by the makers of musical instruments. Wood extractives are in the list of those materials that often do not have a construction role, and their purposeful and correct evacuation can lighten the wood without reducing the stiffness. Carrying out pre-treatments such as fermentation with bread yeast (before water washing and ethanol-acetone washing processes) can lead to the extraction of more extractable substances from wood. In this study, the effect of water washing and ethanol-acetone washing treatments as well as fermentation pre-treatment on the acoustic properties of Ash wood (Fraxinus excelsior) has been investigated.Methodology: Ash wood species (Fraxinus excelsior) was prepared from the wood of a commercial timber and 38 small radial beams with nominal dimensions of 150×12×2 mm (longitudinal×radial×tangential) were extracted from the hardwood. After reaching the equilibrium humidity of 12% in air-conditioned conditions, the selected samples were subjected to the forced vibration test in the free-free beam in order to measure the basic physical and acoustic characteristics. After that, the initial tests were randomly divided into two groups of 19 tests. The first group without pretreatment and the second group with fermentation pretreatment were placed in the process of removing the extractives by water and then by ethanol-acetone mixture. After each step of water washing and removing the extractive substances soluble in ethanol-acetone mixture, the forced vibration test in the free-free beam was performed on the samples and the acoustic properties of the samples were measured.Results: Water washing without pretreatment with bread yeast caused a slight decrease and with pretreatment, it caused a significant decrease in density values (respectively: 1.75 and 7.39%). While the process of removing extractives (with and without pretreatment) by ethanol-acetone mixture caused a significant decrease in density values (Respectively: 2.27 and 8.71%). The modulus of elasticity values showed a significant decrease due to water washing without pretreatment and with pretreatment. (Respectively: 11.37 and 16.47%). The process of removing the extractives by ethanol-acetone mixture also resulted in a significant decrease in the modulus of elasticity values in untreated and pretreated samples (Respectively: 13.87 and 20.93%). Water washing without pre-treatment with bread yeast and with pre-treatment has caused a significant decrease in the values of damping factor, among which the pre-treated samples had a greater percentage of drop in the values of damping factor (Respectively: 13/87 and 20.93%). The process of removing the extractive materials by ethanol-acetone mixture as washing has caused a significant decrease in the damping factor values, which among the pre-treated samples showed a greater percentage drop in the values resulting from this property (Respectively: 3.03 and 18.01%). In this factor, the process of removing the extractive substances soluble in ethanol-acetone mixture (with and without pretreatment) has resulted in a greater drop in damping values (respectively: 6.67% and 20.85%). Acoustic conversion efficiency due to water washing process without pretreatment with baker's yeast caused a slight increase, while pretreatment caused a significant increase in acoustic conversion efficiency values (Respectively: 0.44 and 25.24%). The process of removing extractive materials by ethanol-acetone mixture also caused a significant increase in the acoustic conversion efficiency values, which among the pre-treated samples showed a higher growth percentage in the values of this characteristic (Respectively: 3.41 and 28.90%). Both water washing methods and ethanol-acetone mixture washing were effective in improving the physical (density) and acoustic properties (modulus-elasticity, damping and acoustic conversion efficiency). Meanwhile, the effect of ethanol-acetone mixture washing was more than the effect of water washing. Fermentation pretreatment with bread yeast improved the performance of water washing and ethanol-acetone mixture washing treatments.
Chemical conversion
Zahra Razmpour; ghasem asadpour; kermanian hossein; omid ramezani; Seyed Majid Zabihzadeh
Abstract
Sticky contaminants represent one of the biggest technical challenges in the paper recycling process. These contaminants reduce paper strength, cause plugging of wires and felts, and stick to or deposit on machine parts affecting the runnability of the paper machine In this study, firstly, the sticky ...
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Sticky contaminants represent one of the biggest technical challenges in the paper recycling process. These contaminants reduce paper strength, cause plugging of wires and felts, and stick to or deposit on machine parts affecting the runnability of the paper machine In this study, firstly, the sticky deposit of Docter blade dryer blades was subjected to multi-stage extraction with alcohol, aceton, toluene, and tetrahydrofuran solvents respectively. Then the nature of the resulting material and its physicochemical properties was investigated with FTIR analysis, GC-MS, TGA, XRF, SEM.. The results showed that the deposite originates from fiber, polymers such as polyvinyl acetate and styrene butadiene, which are components of hot melt adhesives, and fatty acid/resin esters. Fatty acids and resins are the most common organic compounds in stickies deposite. the possible origin of these compounds are chemical substances (saponified fatty acids), deinking steps and some resins and fatty acids used in the formulation of adhesives or more resistant resins and extractive materials related to Cellulose fibers. The observed minerals are mainly calcium, iron, silica and aluminum, which are present in the formulation of fillers and coating pigments during the papermaking process
Chemical conversion
mohammad najafianashrafi; Payam Moradpour; Ahmad Jahan latibari; Hamidreza Edalat
Abstract
Poly vinyl acetate (PVAC) adhesive is one of the most important adhesives in wood and furniture industry, which has many advantages such as low cost, environment friendliness and non-toxicity. However, it has some disadvantages such as low water resistance and poor boning strength. In this study, the ...
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Poly vinyl acetate (PVAC) adhesive is one of the most important adhesives in wood and furniture industry, which has many advantages such as low cost, environment friendliness and non-toxicity. However, it has some disadvantages such as low water resistance and poor boning strength. In this study, the effect of nano silica (NS) on the properties of poly vinyl acetate adhesive was investigated. The adhesive formulation with different NS contents (2, 3 and 4%) was added to the PVAC. The structure of the prepared adhesive samples was studied by FT-IR and XRD. We used the wood of Acer tree (Acer cappadocicum) to make joints in this study. Two standards of D882 and ASTM D905 were used for tensile and shear tests, respectively. Results showed that adding NS to PVAC enhanced the tensile strength of films. For example, the tensile strength of prepared films was increased by 30% after adding 4% of NS. Moreover, shear strength test showed that NS up to 3% can improve PVAC bond strength. Viscosity results showed that increasing the weight of NS up to 3% to PVAC glue lead to an increase following a decrease in the viscosity
Chemical conversion
Saeed Hasani; Mohammad Talaei poor; behzad baziyar; Amir Homan Hemmasi; Saeed Mahdavi
Abstract
AbstractIn this study, black poplar (Populus nigra) cut from Zanjan province was used in two age groups of 18 and 38- year-old. Timbers with thicknesses of 4, 5 and 6 cm were prepared from each age group. The prepared timbers were modified during the heat treatment process (Thermowood) at a constant ...
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AbstractIn this study, black poplar (Populus nigra) cut from Zanjan province was used in two age groups of 18 and 38- year-old. Timbers with thicknesses of 4, 5 and 6 cm were prepared from each age group. The prepared timbers were modified during the heat treatment process (Thermowood) at a constant temperature of 212 °C. Experimental samples were obtained from the surface and middle depth of heat-treated timbers. Heat-treated and control wood samples were subjected to accelerated weathering for 150 hours. Color lightness (L*), color difference (ΔΕ*) and water droplet contact angle were measured for heat-treated and control samples before and after weathering. In order to investigation of the wettability content, the method of measuring the contact angle of the water drop - static according to the ASTM D 5946 standard was used. In general, before weathering, the brightness of the heat-treated samples decreased compared to the control sample, but after weathering, the color lightness of the control samples decreased and the color lightness of the heat-treated samples increased. Also, the content of color difference of samples after weathering compared to before weathering showed a significant decrease statistically. Heat treatment increased the contact angle of water droplets of the samples 60.31% and the contact angle of water droplets of the heat-treated and control samples increased significantly after weathering compared to before weathering.
Chemical conversion
Milad Poladi; Seyed Hassan Sharifi; Seyed Majid Zabihzadeh; Mostafa Nikkhah Dafchahi
Abstract
Cellulose is the most abundant bio-polymer and also has many potential and applications, Therefore, in order to convert it to solvable cellulose in many commercial solvents, it is necessary to modify the cellulose structure with a variety of methods of derivation. Cellulose derivatives have an increasing ...
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Cellulose is the most abundant bio-polymer and also has many potential and applications, Therefore, in order to convert it to solvable cellulose in many commercial solvents, it is necessary to modify the cellulose structure with a variety of methods of derivation. Cellulose derivatives have an increasing share in the cellulosic products marketing and it is used in various industries such as sanitary, pharmaceutical, food and industrial., Carboxymethyl cellulose is one of the most important commercial cellulose ether derivatives. The purpose of this study was to investigate the conversion of alpha-cellulose derived from the Deltoides pine species into a useful and more valuable product that called Carboxymethyl cellulose. In order to optimize and investigate the interaction of different process variables, response surface methodology (RSM) was used. For modeling the process, important operational parameters such as concentration of NaOH, ratio of Monochloroacetic acid to cellulose, temperature and the time of etherification as independent variables and the degree of substitution of the samples were considered as the desirable response. Analysis of variance and response level were used to create a function between variables and responses, and optimal conversion conditions were determined. The results showed that the best value presented in the optimal condition proposed by software for the degree of substitution was 31 percent for concentration of etherification, 1.09 for the ratio of Monochloroacetic acid to cellulose, 60 °C for the etherification temperature and 157 minutes for the etherification time.
Chemical conversion
Atefe Rahimi; Ali Abdolkhani; Yahya Hamzeh; Sahab Hedjazi
Abstract
DOR:98.1000/1735-0913.1398.34.124.66.1.9.1580 Rice straw rice is one of the most important lignocellulose wastes in Iran and the world. In this research, rice straw as renewable lignocellulosic materials were used to produce nano-structural lignocellulosic aerogel. For this purpose, rice straw powder ...
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DOR:98.1000/1735-0913.1398.34.124.66.1.9.1580 Rice straw rice is one of the most important lignocellulose wastes in Iran and the world. In this research, rice straw as renewable lignocellulosic materials were used to produce nano-structural lignocellulosic aerogel. For this purpose, rice straw powder was first pre-treated in sodium hydroxide aqueous alkali solution and resulting gel form mixture was transformed into physically bonded lignocellulosic porous and ultra-lightweight aerogel through consecutive processes including freezing-thawing, solvent exchange and freeze-drying. The product properties including apparent density and total porosity were determined, and other physical and chemical properties were evaluated by SEM, FTIR, XRD, nitrogen absorption (BET) and DSC methods. The results showed that a significant amount of the rice straw compounds dissolved in aqueous alkali solution and removed during the subsequent stages of aerogel production. The resulting aerogel showed a nano dimensional structure composed of particles and interconnected nanofibers, which had a great chemical and physical difference from the original rice straw.
Chemical conversion
Niloufar Davodi; Esmaeil Rasooly Garmaroody; Omid Ramezani; Sepideh Haamedi
Abstract
In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent ...
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In this study, in order to control the inhibitory compounds in the bio-refinery, bagasse pith was pretreated under acidic hydrolysis with dilute sulfuric acid 8%, 90 minutes at 120 ° C. Then, by using de-depleting methods of overliming, activated carbon and combining of both, removal of deterrent compounds from the above pretreatment hydrolyzates was performed. In the overliming, calcium hydroxide and sulfuric acid, in activated carbon method, activated carbon was used at three levels (0.5, 1.5 and 2.5%) and in the combined method of the combination of materials in the two previous methods became after acid treatments and each of the methods of insemination, the amount of recovered sugars and the values of the inhibitory compounds of furfural and hydroxymethylfurfural in the hydrolyzate were measured as two important indicators. The results showed that application of the above methods on hydrolyzate increased the yield of reduced sugars, so that the highest sugar yield (˃32%) was obtained after the independent method of overliming. In addition, active and combined carbon autonomous methods (overlimming and activated carbon) have an optimum activated carbon consumption of 2.5 and 1.5%, respectively. The qualitative study of the presence of inhibitory agents in hydrolyzates showed that furfural and hydroxymethylfurfural have maximum absorption at wavelengths of 276 and 282 nm. Also, an overliming with 2.5% activated carbon as the best method could eliminate up to 100% of inhibitory compounds. On the other hand, the autonomous method of overliming, with the removal of ˃90% of the inhibitory compounds, also has the highest sugar yield. Therefore, taking into account simultaneously the rate of sugar yield and the elimination of deterrent compounds, two independent alternatives of Overliming and Overliming with 2.5% active carbon could be proposed for the production of bioassays, such as bioethanol, xylitol, ... from the pith of bagasse.
Chemical conversion
Hamedeh Kiani; Hosein Resalati; Seyed Hassan Sharifi
Abstract
Carboxymethyl cellulose (CMC) is one of the important cellulose derivatives in industries, which is widely used as anti-caking agent, emulsifier, stabilizer, dispersing agent, thickener, and gelling agent. The main raw material of cellulose derivative is cellulose from wood and cotton linter. In this ...
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Carboxymethyl cellulose (CMC) is one of the important cellulose derivatives in industries, which is widely used as anti-caking agent, emulsifier, stabilizer, dispersing agent, thickener, and gelling agent. The main raw material of cellulose derivative is cellulose from wood and cotton linter. In this study, the cotton linter alpha-cellulose was used for producing CMC. Acidified sodium hydroxide process was applied to extract the cellulose from linter alpha-cellulose. Carboxymethyl cellulose was then prepared from cellulose. The optimization of reaction conditions was studied by using response surface methodology (RSM). The design experiment is Box-Behnken design consists of 3 factors (reaction time, % NaOH in mercerization process and mass ratio of monochloroacetic acid to cellulose in etherification process) with 3 levels. Based on it, the optimum values of independent variables are the reaction time of 54.23 min, NaOH concentration of 41.25 % and mass ratio of MCA to cellulose of 1.44 which the CMC had the DS of 0.656, the viscosity of 6634.76 cP. Fourier Transform Infrared spectra (FTIR) were used to characterize the product and starting Cotton Linter Alpha-cellulose.
Chemical conversion
alireza ziapour; Abbas Zare; Mohammad Bakhshi
Abstract
Chemical and biological treatment of dye- containing wastewaters is difficult due to the low adsorption level and chemical stability of dyes. Activated carbon is usually used for adsorption of these materials, but because of high prices and restore problems, researchers trying to find available low-cost ...
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Chemical and biological treatment of dye- containing wastewaters is difficult due to the low adsorption level and chemical stability of dyes. Activated carbon is usually used for adsorption of these materials, but because of high prices and restore problems, researchers trying to find available low-cost materials with high adsorption. In this study, bagasse was used for adsorption of Acid Grange7 dye and its capability was examined. Variables were concentration, temperature, pH and contact time, and the degree of adsorption was examined in different situations. Then, adsorption isotherm according to Langmuir and Freundlich models was investigated. The results showed that the adsorption efficiency depends more on pH of solution and less on temperature of the solution. Maximum adsorption of Acid Orange7 dye by bagasse occurred in the first 15 minutes of contact. The study of adsorption isotherm showed that both models are suitable for description of adsorption of Acid Orange7 dye by bagasse. Maximum adsorption of Acid Orange7 dye by bagasse was calculated as 18.56 mg/g. Results of this study showed that bagasse could be used as a low-cost bio adsorbent for the adsorption of Acid Orange7 from aqueous solution.
Chemical conversion
Mahmoud Rouhbakhsh Bidaei; Mohammad Azadfallah; Rasoul Yarahmadi
Abstract
Dyes release into waste water due to its toxicity for some organisms results in major environmental pollution problems. The activated carbon (AC) is an efficient adsorbent to remove this kind of pollutants from aqueous phase. Hence, in this research activated carbon was prepared from sound and rotted ...
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Dyes release into waste water due to its toxicity for some organisms results in major environmental pollution problems. The activated carbon (AC) is an efficient adsorbent to remove this kind of pollutants from aqueous phase. Hence, in this research activated carbon was prepared from sound and rotted beech wood by chemical activation method and its adsorption capacity for removal of Rhodamine B was assessed. The carbonization and activation steps were performed at single stage with impregnating the substrate by zinc chloride as activating agent and with the ratio of 75, 100 and 125 percent to raw material mass at 400 and 500 ºC. The results showed that with increasing the impregnating agent content, the iodine number of ACs from both woods enhanced. The yield of AC from sound wood decreased with increasing impregnating agent while it was not predictable for AC resulted from rotted wood. Scanning electron microscopic (SEM) studies revealed much morphological changes in the surface of rotted wood-AC in comparison with sound wood -AC after treatment with activating agent. Also, raising the activating temperature from 400 to 500 ºC caused to enhance the iodine number. All prepared ACs performed much efficient in removal of Rhodamine B from aqueous solution. The maximum adsorption of the dye was obtained for ACs prepared under impregnating ratio of 125 and activating temperature of 500 ºC.
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.
Chemical conversion
Seyyed Pedram Hashemi Beygzadmahalleh; Seyyed Peyman Hashemi Beygzadmahalleh; Asghar Tabei
Abstract
This study has been conducted to determine morphological characteristics of fibers and amount of chemical components of grapevine branches cultivated in Astara in province of Guilan. For this purpose the number of 53 branches, with same size and diameter, were cut from some grapevine and sent to laboratory ...
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This study has been conducted to determine morphological characteristics of fibers and amount of chemical components of grapevine branches cultivated in Astara in province of Guilan. For this purpose the number of 53 branches, with same size and diameter, were cut from some grapevine and sent to laboratory of wood and paper industries in Islamic Azad university Astara branch. To separate the fibers and for studying their morphological characteristics, wooden chip sampling from the branches was conducted at 3 heights of them (5%, 50% and 75%). Fiber separation was done by method (Franklin 1954) and then dimensions of fibers and their biometric coefficients were determined. From a number of separated branches, wood flour was prepared in two modes of with skin and without skin and then, percentage of chemical components of them was determined according to TAPPI standard. The overall average percentage of holocellulose, alpha cellulose, hemi cellulose, cellulose, lignin, acetone extractives, alcohol extractives, hot water extractives, cold water extractives and ash were measured as 87.59, 56.99, 30.59, 47.20, 25.16, 5.90, 2.53, 4.41, 1.79 and 1.79 percent, respectively. Also, the total average of fiber length, fiber diameter, lumen diameter and cell wall thickness were measured as 0.96 mm, 26.45 µm, 15.48 µm and 5.49 µm, respectively. Also, the total average of slenderness, flexibility and runkel coefficients were calculated as 36.29, 58.50 and 0.71, respectively. The results showed that, in the debarked branches of grapevine trees, the amounts of holocellulose, alpha cellulose, hemi cellulose and cellulose are more than with skin branches and debarked branches have less lignin, extractives and ash than with skin branches. Also. The results showed that dimensions of the fibers including fiber length, fiber diameter and fiber lumen diameter, except cell wall thickness, decreased with increasing of height.
Pulp and paper
Hosein Valayi; Ahmad Jahan Latibari
Abstract
Strength properties and the yield of soda and soda-ethanol pulps produced using hornbeam, beech and poplar woods were investigated. Soda pulps were produced applying 20% active alkali and the soda-ethanol pulps were made using 10% active alkali and 50% ethanol. The pulping temperature was constant at ...
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Strength properties and the yield of soda and soda-ethanol pulps produced using hornbeam, beech and poplar woods were investigated. Soda pulps were produced applying 20% active alkali and the soda-ethanol pulps were made using 10% active alkali and 50% ethanol. The pulping temperature was constant at 175 C and the soda pulping time was selected at 120 minutes and the soda-ethanol pulping times were 120 and 180 minutes. The highest accepted pulping yield at 58.54% was reached using soda pulping on poplar wood and the lowest yield (49.29%) was related to soda-ethanol pulp produced from beech wood applying 180 minutes pulping time. The accepted yield of soda-ethanol pulping was low, but the kappa numbers of these pulps were almost 20 units lower than soda pulps. The strength properties of soda-ethanol pulps were superior to soda pulps and the difference was statistically significant at 99% confidence level. The results of this study indicated that the delignification of soda-ethanol pulping process is faster than soda pulping from the selected hardwoods especially poplar wood.
Chemical conversion
mahdiye mazandarani; ali ghasemian; ahmadreza Saraeyan; mahdi mashkour; SeyedRahman Jafari Petroudy
Abstract
In the present study, preparation of cotton stalk (Sahel variety) as one of the common agricultural residues was studied through three stages as Soda-AQ chemical pulping, delignification and alkaline treatment, aiming for the production of cellulose nanocrystal. In order to identify the optimum condition ...
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In the present study, preparation of cotton stalk (Sahel variety) as one of the common agricultural residues was studied through three stages as Soda-AQ chemical pulping, delignification and alkaline treatment, aiming for the production of cellulose nanocrystal. In order to identify the optimum condition for the preparation of cellulose nanocrystal, acidic hydrolysis of the produced alpha-cellulose was done using 64% sulfuric acid, 25, 35 and 45 minute as time and at 35, 45 and 55 degree centigrade as temperature. Atomic Force Microscopy (AFM), X-Ray Diffraction, and Dynamic Light Scattering (DLS) were used to identify the quantitative and qualitative properties of cellulose nanocrystals. AFM micrographs showed that more severe condition of the treatments decreased the thickness of the cellulose nanocrystals. XRD results also demonstrated that the preparation stages of alpha-cellulose as well as acidic hydrolysis treatments much effectively increased the degree of crystallinity. DLS results indicated that 98.7 percent of the produced nanocrystals under the condition of 55 degree centigrade and 45 minute were in the range of 18-95 ηm, whose highest abundance was in the range of 18-39 ηm. Thus, the mentioned condition were determined as the best and optimum condition for the production of cellulose nanocrystal from cotton stalk cellulose.
Chemistry of wood
Seyyed Peyman Hashemi Beygzadmahalleh; Seyyed Pedram Hashemi Beygzadmahalleh; Asghar Tabei
Abstract
Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of ...
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Tobacco (Nicotianan tabacum) and an old industrial plant in the north, Iran to supply tobacco leaf to produce significant amounts of stem tobacco cultivation and the annual production is in the north of the country. In this research stems of tobacco variety Coker 347 randomly Gilan district, city of Astara was prepared according to the TAPPI standard test, wood flour were prepared and extractives were determined. The results showed that the mean shoot extractive tobacco varieties Coker 347 (10.41 percent). The extractive solvent toluene - ethanol volume ratio (2 : 1) of milled wood was extracted. Extractive made into a glass vial and transferred to the BSTFA reagent was added. Samples for one hour at room temperature and 70 ° C water bath and then by (GC / MS) were analyzed. Atotal of 11 chemical compounds in tobacco stem wood extractives variety Coker 347 were identified with different percentages of tobacco stem wood Coker 347 varieties exist. These compounds include, P- Prydyn , 1 – tri methyl Saylyl , 1,2 - benzene di- carboxyl acid , alpha - D - Golokopyranoz , 11, 8 – di methyl - 13 - (4 - aksu -1 - methyl ) , tri Floyver methyl isopropyl sulfide are the highest values.
Pulp and paper
Abbas Fakhryan roghani; Abdolrahman Hosseinzadeh; Fardad Golbabaei; Hossein Hosseinkhani
Abstract
Three 4,6 and 12 years old populus deltoides trees were randomly selected and felled from the Safrabasteh Research Station located in Gilan province. Samples were transferred to the Wood chemistry and Paper Making of Research Institute of Forest and Rangelands. By using of kraft processing, percentage ...
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Three 4,6 and 12 years old populus deltoides trees were randomly selected and felled from the Safrabasteh Research Station located in Gilan province. Samples were transferred to the Wood chemistry and Paper Making of Research Institute of Forest and Rangelands. By using of kraft processing, percentage of sulfidity rate of %25, and the temperature of 165°C a addition to modification of effective alkali, up to 14%, 17%, 20% and cooking time at maximum temperature of 60 min., 120 min., 180 min., with a rate of liquide to lignocellulosics malerial equivalent at 5/1 (L/W).Average of yield and kappa number of pulps was measured between 43.83-2.20 and 14.85-30.48 respectively.Pulps were refined up to the freness degree of 350, 400 and 450 c.s.f for 14% effective alkali and 350 c.s.f. for 20% effective alkali. The mechanical properties of 60 grams hand-made papers include breaking length, burst Index, tear Index and folding were also measured.
Chemical conversion
Abbas Fakhryan roghani; Abdolrahman Hosseinzadeh; Fardad Golbabaei
Abstract
Threes, six and 12 years old sample trees of Populos deltoides 77.51 were randomly selected and felled at the safrabasteh research station located in Gilan province. Sample tree transferred to the Alborz research center- Karaj for Laboratory studies; The Laboratory studies included determination of physical, ...
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Threes, six and 12 years old sample trees of Populos deltoides 77.51 were randomly selected and felled at the safrabasteh research station located in Gilan province. Sample tree transferred to the Alborz research center- Karaj for Laboratory studies; The Laboratory studies included determination of physical, anatomical and chemical composition of revealed that with increasing trees age, fiber length and fiber diameter increased. There was significant differences among three ages studied at I percent probability.
Physics and anatomy
Saeed Mahdavi; Abdolrahman Hosseinzadeh; Abbas Fakhryan roghani; masoudreza habibi
Abstract
In order to evaluate reed as a raw material for wood & paper industries, three main regions of Iran consist of south, North and East were selected for this study. Phragmites australis is dominant species in these regions and this study concentrated on it as well.Chemical components and biometry of ...
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In order to evaluate reed as a raw material for wood & paper industries, three main regions of Iran consist of south, North and East were selected for this study. Phragmites australis is dominant species in these regions and this study concentrated on it as well.Chemical components and biometry of fibers were determined with four and thirty replications respectively. Statistical analysis showed that there were no significant differences among three regions in fiber length and lumen diameter but reversely fiber width and cell wall thickness showed significant differences. The highest fiber length mean was 1.39mm. For North (Anzali) Coefficients of papermaking of fibers also were calculated for each region. Biometerical fiber results, showed that P. australis has good fiber compare to the Iranians hardwoods as papermaking.The results also showed that there are significant differences between regions and subregions at %5 level. North had the highest and lowest cellulose and lignin contents respectively. These results also proved that P.australis is one of the best Iranians' raw materials as cellulose and lignin contents between the others.
