Pulp and paper
Mahdis Shafaee; Ali Ghasemiyan; Mohammad reza Dhghani Firozabadi; Poneh Ebrahimi
Abstract
In recent years, there has been a lot of attention in producing and using of renewable and environmental friendly cellulose film and coverage. Regarding to the application of these films and coverages in different industries such as food, packaging and medical industries, their antimicrobial property ...
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In recent years, there has been a lot of attention in producing and using of renewable and environmental friendly cellulose film and coverage. Regarding to the application of these films and coverages in different industries such as food, packaging and medical industries, their antimicrobial property is apparent. The purpose of this research is producing cellulose antibacterial film. At first, long fibr pulp convert to NFC using a supergrinder and then nanosilver treated films prepared applying silver nitrate through two different ways. In the first method, silver nanoparticles with considerations of 5 and 10 ppm reduced on NFC particles’ surface using retention aid. In second methods the prepared NFC film has been immersed in solution of Ag nanoparticle in concentration levels of 5 and 10 ppm. On higher concentration of used nanosilver solution, the amount of retained Ag nanoparticle in the first method was higher than the second one whereas, on lower concentration one, the differences of retained nanosilver values between two methods was a little. It has worth of mentioning that immerging method has the benefit of avoiding Ag nanoparticle wasting during pulp draining and nanosilver solutions could be reused simply.
Pulp and paper
Mehrnoosh Tavakoli; saraeyan ahmad reza; hossein resalati; ali ghasemian
Abstract
The present study was carried out aiming to investigate the effect of using Deinked Mixed Office Waste Pulp (MOW) on the properties of Alkaline Peroxide Mechanical Pulp (APMP) from cotton stalk. APMP pulps was prepared using chelating agents such as Na2SiO3 and DTPA (control sample) and without ...
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The present study was carried out aiming to investigate the effect of using Deinked Mixed Office Waste Pulp (MOW) on the properties of Alkaline Peroxide Mechanical Pulp (APMP) from cotton stalk. APMP pulps was prepared using chelating agents such as Na2SiO3 and DTPA (control sample) and without these agents in two-stage pulping withL/Wratio 6:1(ml/g), 20 minutes impregnation time at 70 0Cfor firststage, 60 minutes impregnation at 75 0Cfor second stage. Also, pulp was preparedfrommixed office waste paper, whichweredeinked with conventional flotation and then each pulp was separately refined up to about 300 ml CSF. The handsheets were made from control sample pulps, APMP without chelating agents, MOW deinked pulp and mixing with 10%, 20% deinked pulp with control APMP. Physical and mechanical properties were determined using TAPPI standard methods. Deinked MOW pulp had the maximum values of density, brightness, strength properties and APMP pulp without chelating agents had the minimum values. Among mixed pulps, APMP pulp containing 20% deinked MOW pulp showed the maximum value of density, brightness, burst index and tear index.
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.
Physics and anatomy
Elahe Mehri; Ali Ghasemian
Abstract
The aim of this study was to investigate biometrical properties of bark, node and internode chemical components of Bamboo phyllostachys pubescens. The results showed, there were significant difference between fiber length of bark, node and internode; and internode had maximum fiber length and node had ...
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The aim of this study was to investigate biometrical properties of bark, node and internode chemical components of Bamboo phyllostachys pubescens. The results showed, there were significant difference between fiber length of bark, node and internode; and internode had maximum fiber length and node had minimum fiber length. There were also significant difference between lumen diameter and cell wall thickness; and node had the highest value. In terms of chemical compositions; amount of extractives, lignin and ash of node were more than internode, but there weren’t significant differences at the 95% confidence, while the amount of cellulose of internode was significantly more than node. Slenderness ratio, flexibility ratio and Raunkel ratio were also calculated for bark 93.06, 36.641, 172.916% and for node 46.308, 33.108, 202.035% and for internode 88.151, 31.678, 215.666% respectively. Generally the observations indicated that, according to the characteristics of the fiber of this nonwood plant, it can be recommended to produce pulp and paper.
Soodeh Zhand; Masieh Masoudifar; Ahmad Reza Saraeian; Ali Ghasemiyan
Abstract
In this study the effect of alkaline pretreatment with 1% NaOH on physical, optical and mechanical properties and refining of NSSC (Neutral Sulfite Semi Chemical) wheat straw pulp were investigated. The wheat straw (Zagros Sp.) was obtained from croplands Golestan province. Splinted wheat straw was pretreated ...
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In this study the effect of alkaline pretreatment with 1% NaOH on physical, optical and mechanical properties and refining of NSSC (Neutral Sulfite Semi Chemical) wheat straw pulp were investigated. The wheat straw (Zagros Sp.) was obtained from croplands Golestan province. Splinted wheat straw was pretreated with 1% NaOH(on the basis of OD weight) at 70 degrees for 30 minutes. The main pulping was performed at 160 ˚C with the fixed ratio of 5:1 Na2S03 and NaOH. After pulping defibration was done by lab-refiner to 380±25ml (CSF) and total yield and changes in Kappa was determined. Hand sheets of 60 gr. /m² were made on the basis of TAPPI standard and physical, optical and mechanical properties determined. The results show that alkaline pre-treatment has a significant effect in increasing of physical, optical and mechanical properties. Calculating primary freeness of pulps indicates that by increasing chemical compounds and NaOH, freeness decreases and that by increasing chemical compounds paper density increases, whereas yield, caliper and bulk decrease.
Saeid Kamrani; Ahmad reza Saraeian; Hossein Resalati; Ali Ghasemian
Abstract
The main objective of this study was to determine the trends of fiber dimension variation along the longitudinal direction of wheat straw as a criteria for papermaking. Zagross wheat straw was collected from the agricultural and natural resources research center, Golestan province .The fiber biometric ...
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The main objective of this study was to determine the trends of fiber dimension variation along the longitudinal direction of wheat straw as a criteria for papermaking. Zagross wheat straw was collected from the agricultural and natural resources research center, Golestan province .The fiber biometric characteristics including fiber length, fiber diameter, lumen diameter and cell wall thickness in three internodes were determined .Results showed that, the difference in fiber diameter, lumen diameter and cell wall thickness were sttistically significant between three internodes of wheat straw at 99% confident Based on the computed papermaking indices (flexibility ,softness and runkle number), it was predicted that the papers produced from the first and the third internode of wheat straw may have higher tensile,folding and burst strength and the papers produced from the second internode may have higher tear strength.
Pulp and paper
Mohammad taghi Asdolah zadeh; Hossein Resalti; Ali Ghasemian
Abstract
In the present study the effects of hot water pre-extraction and alkaline catalyzed were evaluated on soda-aq pulping of kenaf whole stem. In this respect, following kenaf chips pre-extraction at various temperature and time conditions, pulp preparation were carried out on oven-dried weight loss levels ...
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In the present study the effects of hot water pre-extraction and alkaline catalyzed were evaluated on soda-aq pulping of kenaf whole stem. In this respect, following kenaf chips pre-extraction at various temperature and time conditions, pulp preparation were carried out on oven-dried weight loss levels of 8.5, 11.5 and 14.5 % of the samples, and the reference untreated kenaf chips performed by using Soda-AQ at 3 levels of H-factors ( 983, 1408 and 1832 hours). Results indicated that kenaf chips weight losses increased while the pre-extracted pH decreased as pre-extraction temperature and time increased. The required H-factor for achieving certain level of weight loss was reduced by adding small amounts of alkali (0.15 % on oven dried kenaf) on hot water extraction stage. The Pulp yields were reduced by increasing cooking H-factor and extracted weight loss. Averages comparison indicated that significant differences were observed, at 95% confidence, between the pulp yield and kappa number from reference pulp and pre-extracted pulp samples at levels of about 8.5, 11.5 and 14.5 %, and pulp yields and their kappa number were higher in reference pulps than pre-extracted samples. In addition, pulp yield average was higher in pre-extracted samples by alkaline catalyzed than pre-extracted samples by hot water, however, no significant differences were observed between their kappa number average. Meanwhile, to obtain a certain (similar) kappa number, pre-extracted kenaf chips in comparison with reference untreated kenaf chips require lower H-factor.
Hossein Shob chary; Ahmad reza Saraeyan; Ali Ghasemian
Abstract
This study was conducted to investigate the properties of cotton stalks APMP pulp. APMP prepared from chipped cotton stalks. the pulps were prepared separately from debarked and bark containing stalks using three two-stage treatments.Sodium hydroxide charge as a constant level of 4% and hydrogen ...
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This study was conducted to investigate the properties of cotton stalks APMP pulp. APMP prepared from chipped cotton stalks. the pulps were prepared separately from debarked and bark containing stalks using three two-stage treatments.Sodium hydroxide charge as a constant level of 4% and hydrogen peroxide at three levels of 0, 1 and 2% were used in to two-stages, sodium hydroxide as a constant level of 2% and hydrogen peroxide at three levels of 2, 3, 4% were applied. Other conditions of pulping was time's of 20 min for first stage and 100 min for second stage, temperature 70°C and l/w:6:1 as fixed factors considered. Pulp yield determined after neutralization and defiberation. All the pulps were refined up to 300 (ml, CSF) freeness and handsheets were made, then and properties of papers measured using TAPPI standards. Results showed that the pulp yield and brightness was higher in free-bark compared to bark-containing conditions. Also paper produced in free-bark condition with cotton stalks core, resulted the higher tensile and burst indexes and higher breaking length compared to whole cotton stalk.While tear index didn’t show significant difference.Generally, caliper and bulk rates were high in total treatments (free-bark and bark-containing conditions) from cotton stalk APMP process.
Pulp and paper
Ali Khalili gasht rodkhani; Ali Ghasemian; Ahmad reza Saraeyan; Mohammad Dahmardeh ghale no; Sayed mehdi Manzorolajdad
Abstract
This study was aimed to investigate the effects of mixing OCC fibers with mixed hardwoods kraft pulp at Iran Wood and Paper Industry Co (Chuka). OCC has been repulped according to the common method in paper recycling industry and its freeness, along with that of virgin kraft pulp, were measured. The ...
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This study was aimed to investigate the effects of mixing OCC fibers with mixed hardwoods kraft pulp at Iran Wood and Paper Industry Co (Chuka). OCC has been repulped according to the common method in paper recycling industry and its freeness, along with that of virgin kraft pulp, were measured. The pulps were beaten to reach the required freeness values to make kraft liner paper, and have been then mixed at 10/90, 20/80, 30/70, 50/50 and 70/30 percentage rates of OCC and virgin kraft pulp, respectively. Handsheets were made from each composition and their mechanical and optical properties have been measured, according to required standard test methods, and compared with those of the control (100% virgin kraft pulp), using ANOVA method. Grouping of the mean values was done by Duncan test and normalization equation was computed to determine the best treatment. The results indicate decreasing the values of tensile, tear and burst, folding endurance and density in comparison with those of the control (100% virgin kraft pulp), but bulk, thickness and opacity have been increased. The score belonging to each treatment show to produce paper possessing proper mechanical and optical properties using OCC fibers, the allowed proportion of these fibers is 50 percent.
Pulp and paper
Hamid Noori chaparprdy; Ali Ghasemian; Ali Shalbafan; Reza Hajihassani
Abstract
This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated ...
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This study has been performed in order to determination of optimum refining of paper made of recovered Kraft liner. Recovered Kraft liner has been prepared from anzali city. After shredding into 5 centimeter pieces, the papers were soaked in distillated water in pail. After 7 days fibers was separated of each other by disintegrator and freeness for each pulp before and after refining were measured. They were refined in revolutions of 3000, 6000, 9000, 12000 by PFI mill. Hand sheets were made from each revolution in order to TAPPI standard T 205om-95 number, and then were compared with control sample. Analysis of variance of waste papers were conducted using completely randomized design, then mean values were compared, using Duncan’s test, and finally the normalization equations were used to determine the best sample. Results showed that increasing of refining revolution increased strength of burst, tensile and brightness but decrease freeness, thickness and tear strength at product. Normalization equations showed that the best papers made from refining revolution of 9000.
