Composite wood products
Mohammad Ahmadi; Bita Moezzipour; mearaj sharari
Abstract
In this study properties of fibers recycled from MDF wastes as one of the potential important resources as raw materials for MDF production were investigated. For this purpose, two different methods including ohmic heating (for 2 and 4 min) and hydrothermal method (at 105˚c for 150 min) were utilized ...
Read More
In this study properties of fibers recycled from MDF wastes as one of the potential important resources as raw materials for MDF production were investigated. For this purpose, two different methods including ohmic heating (for 2 and 4 min) and hydrothermal method (at 105˚c for 150 min) were utilized for recycling the wastes of MDF and original fibers were studied as control sample. The chemical composition of fibers (lignin, cellulose and hemicellulose content), as effective variable on quality of fibers was measured. Also for probing the chemical characteristic of fiber surface, FT-IR test was utilized. In addition, the wettability of fibers also was determined by measuring the contact angels between fibers surface and water drop. The results showed that the chemical composition of fibers is changed within recycling process. Most changes were occurred in hemicellulose and extractives content. The results of FT-IR test revealed the existence of more carbonyl groups and furfural and lower amount of hydroxyl groups in recycled fibers compared to original fibers which caused by esterification process. The wettability of fibers was decreased after recycling process especially in hydrothermal method.
Mohammad Alishahi; Omid Ramezani; Hossein Kermanian; Mehdi Rahmani nia; Seid Atefeh Nasiri; Sahar Jalalvand
Abstract
In this research, the influence of paper drying condition, as one of the most important variable in paper recycling, on the characteristics of fibers was studied. In this respect, bagasse soda pulp was collected from Pars Paper mill in Khozestan province and handsheets were made. The control hand sheet ...
Read More
In this research, the influence of paper drying condition, as one of the most important variable in paper recycling, on the characteristics of fibers was studied. In this respect, bagasse soda pulp was collected from Pars Paper mill in Khozestan province and handsheets were made. The control hand sheet samples were dried at room temperature and the rest of the handsheets were dried using drum dryer set at 60° C for 3 hours, 100° C for 50 minutes and 120° C for 25 minutes to reach the same moisture content as the sheets dried at room temperature. Then, these handsheets were slushed in water and the pulp properties were determined. The results showed that with increasing the drying temperature, cellulose content did not change while hemicelluloses were reduced. Although the assessment of changing the lignin content with micro kappa method showed an increasing trend, but based on previous literature, it was concluded that the result are not justified. Also, the results indicated that changing the degree of polymerization and crystallinity did not show a consistent trend, showing initial reduction following by increased values. These results were attributed to interaction effect of drying temperature and time.
Saeid Mahdavi; Masoudreza Habibi
Abstract
Cereal straws including grain sorghum varieties can be used for pulp production due to the significant amount of residual straw after harvesting. This study showed that there are no significant differences between fiber dimension and papermaking coefficients of two varieties of sorghum (Kimia and Sepideh). ...
Read More
Cereal straws including grain sorghum varieties can be used for pulp production due to the significant amount of residual straw after harvesting. This study showed that there are no significant differences between fiber dimension and papermaking coefficients of two varieties of sorghum (Kimia and Sepideh). The average of fiber length, fiber width, lumen diameter, and cell wall thickness were measured as 1.19 mm, 23.20, 15.34, and 3.93 µm, respectively. Significant difference (P < 0.05) was found among all chemical composition of two varieties except lignin content. The average content of holocellulose, alpha-cellulose, lignin, extractive, and ash were determined as 62.13%, 37.71%, 21.05%, 9.58% and 6.97%, respectively. The result revealed that pulp strength produced from Sepideh variety was better. However it requires more intense delignification compared to Kimia variety. The highest screen yield (33.19%) was reached applying the treatment combination of 170°C, 12% NaOH, and 75 minutes from the Sepideh variety. Sorghum pulp could be combined with the virgin pulp to compensate cellulose raw material shortage in paper industry.
Pulp and paper
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 ...
Read More
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.
Saeideh Sharifi; Jalil Roshanasan; Sayed zya aldin Hosseini
Abstract
Okaliptus is a fast –growing and light – liking tree that its trunk is smooth and is shelled spontaneously. n a short time its diameter and height increase.for its fast growing. So that turing it into things is difficult Fiber s traction is high and deksity is 0.55 to 0.58 a square centimeter. ...
Read More
Okaliptus is a fast –growing and light – liking tree that its trunk is smooth and is shelled spontaneously. n a short time its diameter and height increase.for its fast growing. So that turing it into things is difficult Fiber s traction is high and deksity is 0.55 to 0.58 a square centimeter. The samples were prepared from the branches and trunk of Ocalyptus Kameldolensis with the average old of three years, from Jiroft region in Kerman province. After ordaining the age and having samples from the same age , some discs were prepared for cutting to measure fibers.Making ready and suspension of fibers were done in Fraklin method .Measuring amaout of lignin was done to standard no: T222- om – 88 and TAPPI guide directions . Measuring cellulose was done according to Nitric Acid method and due to standard No : T264 – om – 88 , and TAPPI guide directions. Due to results the length of trunk fibers was 811.36 and branches was 845.68 micro meters.Diameter of trunk fibers is 19.3 but branches 15.64, these amounts don,t have a meaningful differnce the level of 5&1 percent . Diameter of the carity of rrunk fibers was 10.71, but branches 3.44 at the level of 5&1 percent , they don,t have a meaningful difference. The amount of extracted articles of trunk is 4/5 but branches 2.3 percent ,and amount of lignin in trunk was 35.66 but in the branch 24.66, and amount of cellulose in trunk was 55.66 and the branch 46.81 percent which at the level of 5&1 percent have a meaningful difference . The amount of Ashes from trunk was 0.73 but from the branch 0.88 that at the level of 5&1 percent , don,t have a meaningful defference.
Physics and anatomy
Saeed Mahdavi; Abdolrahman Hosseinzadeh; Hossein Familian; masoudreza habibi
Abstract
Cross sectional disks were cut at breast height from three 17-year-old trees of E.camaldulensis grown in Pasand research station in Mazandaran province. Ring width, wood density, and fiber dimension were measured for each two rings from pith to the bark. Overall average disks, fiber length, fiber width, ...
Read More
Cross sectional disks were cut at breast height from three 17-year-old trees of E.camaldulensis grown in Pasand research station in Mazandaran province. Ring width, wood density, and fiber dimension were measured for each two rings from pith to the bark. Overall average disks, fiber length, fiber width, lumen diameter, and cell wall thickness were measured at 758, 15.93, 8.63, and 3.65 micrometer respectively. Mean values for the oven dry and basic. Density was 0.708 g/cm3 and 0.552 g/cm3. Cross sectional \ growth rate and wood production for the trees were measured at 11.1 mm and 12.3 m3/ha./year respectively. Chemical compositions of the wood consist or cellulose, lignin, extractives (in acetone soluble) and ash were measured at 47.44%, 30.87%, 6.96%, and 0.27% respectively. The result showed that E.camaldulensis is classified as short fiber hardwood with low frequency. Fiber dimensions and density slightly increased from pith to the bark. There was high significant correlation between cell wall thickness and density, while; there was no significant correlation between ring width and the others. Among the properties studied, cell wall thickness and fiber length showed the most variations.
