• Journal of Korean Society of Forest Science
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• v.61 no.1
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• pp.27-36
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• 1983

This study was performed to get the basic information on nitric acid pulping of beech wood. In order to reduce the consumption of nitric acid, alkali pretreated woods were applied to a nitric acid pulping process. It consisted of nitric acid treatment to a high residual lignin content and the subsequent delignification with alkali, required far less chemical than the single stage method. At the first stage of nitric pulping, pulp yield descreased with increasing cooking time and 3 percent of nitric acid was more effective on the delignification of wood than 1 or 2 percent. Alkali pretreatment of wood improved significantly the rate of delignification, and 79 percent of the pretreated yield was good enough for excellent delignification. The dissolution of carbohydrate (mainly xylose) was increased with increasing cooking time, especially at the second stage. It would be considered that carbonyl groups introduced to polysaccharides in wood by nitric acid oxidation caused the degradation of carbohydrates.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.3
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• pp.50-57
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• 2014

In this study, we investigated the physical properties of kraft pulps made from rice husk, peanut husk and garlic stems. These agricultural byproducts were collected individually, and then various pulps were manufactured from them by controlling active alkali, sulfidity, reaction time and the liquor ratio in the kraft pulping process in order to analyze the applicability of these agricultural byproducts as raw materials for kraft pulps. After kraft pulping, we measured yield, flake content, fiber length, fiber width and freeness of pulps, and the fiber shapes of the pulps were observed by using an optical microscope. When the higher active alkali, longer reaction time and lower liquor ratio were applied in kraft pulping process, reject content decreased and fiber yield increased. The pulp from garlic stems had the longest fiber length and that from rice husk showed the highest intial freeness. All of the pulps from agricultural byproducts showed higher initial freeness, shorter fiber length and the similar fiber width compared to OCC, BCTMP and hardwood BKP. The fibers of the pulps made from agricultural byproducts showed a similar shape to those of commercial pulps. It was concluded that these agricultural byproducts had a potential as raw materials to produce an alternative pulp to the commercial pulps.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.1
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• pp.13-18
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• 2003

This study was done in an effort to evaluate the possibility of recyclability of moisture-proof paper. Because it is difficult to recycle laminated moisture-proof paper, a mixture of styrene-butadiene latex(SB latex) and wax emulsion was used as moisture-proof paper chemicals. A bar coater was applied to make moisture-proof paper and the coated weight was 17 g/$m^2$. The mixing ratios of SB latex to wax emulsion were 85 : 15, 87 : 13, and 90 : 10, respectively. It was observed that the moisture-proof paper treated with SB latex and wax emulsion at the appropriate ratio could be recycled effectively. The moisture-proof paper was similar to base paper in degree of pulping, and there was no significant difference in dispersion between moisture-proof paper and base paper. Most of wax particle which caused the spots during drying process could be removed by flotation process. Tensile strength and tear strength of handsheets made of both moisture-proof paper and base paper after pulping was measured to examine the fiber bonding and no significant difference in mechanical properties was observed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.2
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• pp.58-67
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• 2000

This study was carried out to acquire basic data necessary for the use of non-wood pulp. Various chemical pulping methods for rice straw to achieve higher yield, lower Kappa No. were investigated and then the physical properties of various pulps were tested. The results of this study were as follows: When various chemical pulps (Soda, Soda-AQ, Soda-$H_2O_2$, Soda-$Na_2S_2$, AS, AS-AQ, AS-$Na_2S_2O_3$, AS-$Na_2S_2O_4$, Kraft) were produced with rice-straw, the pulps with the highest yield and lowest Kappa No. were obtained with Soda-$Na_2S_2$and AS-$Na_2S_2O_4$pulps. For the breaking length, Soda and Soda-additive pulps(7.5~9.2km) were better than AS and AS-additive pulps(6.2~8.1km). Similarly, for the burst index, Soda and Soda-additive pulps(6.0~7.0 kPa.$m^2$/g) were better than AS and AS-additive pulps(4.5~6.3 kPa.m$^2$/g). But the tear index was showed 21.8-30.9 mN.$m^2$/g with a little different between pulping methods.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.48 no.2
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• pp.13-19
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• 2016

Moso Bamboo was investigated as the a raw material for pulp and paper industry. Soda-Anthraquinone (Soda-AQ) pulping, elemental chlorine free bleaching was applied. Yield of soda or soda-AQ pulp was 29.3-31.7% with Kappa number 33.0-22.8 with different cooking time or anthraquinone addition at 20% active alkali. In soda or soda-AQ pulping, 81-86% of xylan was removed, which was the main reason for lower pulp yield than hardwood species. Average fiber length of Moso Bamboo soda-AQ pulp was 1.36 mm with $15.5{\mu}m$ fiber width. Soda-AQ pulp from Moso Bamboo (P-3, lowest Kappa pulp) was bleached with 5.5-6.5% of chlorine dioxide charge as D0ED1 bleaching sequence. In 3-stages ECF bleaching, final brightness of 85.3% ISO was achieved with total chlorine dioxide 6.5%.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.42 no.3
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• pp.22-27
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• 2010

Pulping properties of the imported mixed eucalyptus chips and the domestic yellow poplar chips were investigated for comparing two chips as the raw materials for the hardwood chemical pulp. Soda-AQ (anthraquinone) pulping was applied for this study. The pulp from yellow poplar showed higher pulp yield than pulp from mixed eucalyptus, which comes from the lower hot-water soluble extractives and the higher polysaccharides in yellow poplar chips than those of the mixed eucalyptus chips. The yellow poplar pulp had higher average fiber length and fiber width than those of the mixed eucalyptus pulp, which led to the better respond to beating and the higher tear strength than those of the pulp from the mixed eucalyptus chips.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.2
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• pp.58-64
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• 2003

Because of its tendency of making strong Hoc on the fiber surface with fines, Meogujaengi has not been valued as a material of Hanji. As an attempt to manufacture high value-added products using the material made from Jumchihanji, this study performed morphological classification and chemical component analysis and selection of pulping of Meogujaengi method. As a result, it can be concluded as follows, 1. Meogujaengi is assumed to be a local variety of Broussonetia karinoki and its outward appearance is distinguished from Broussonetia kazinoki. 2. The bast fiber of Meogujaengi is longer and thinner than that of Broussonetia papyrifera or Broussonetia kazinoki. However, because of the coarse linear of fiber tissue, there are many clusters. 3. The cluster phenomenon of Meogujaengi is nothing to do with its chemical components. Although the contents of its chemical components are different from those of Broussonetia kazinoki, no component was found that obstructs pulping. 4. The pretreatment for suppressing the occurrence of clusters of Meogujaengi was effective, and it was necessary to do secondary beating using hollander beater after beating mixed with PAM using knife beater.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.2
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• pp.31-39
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• 2011

The applicability of arrowroots as materials for paper manufacture was investigated by evaluating the characteristics of arrowroots pulping and pulps, and the surface characteristics of paper made of arrowroots. The results is as follows. The yield of grounded pulp, alkaline pulp, grounded bleach pulp, and alkaline bleach pulp are 98.0%, 37.7%, 84.8%, and 32.5%, respectively. The extraction components in arrowroot's fibers was shown high in 1%-NaOH extraction. The amount of holocellulose and lignin were largely decreased, but a slight decrease was shown in the bleaching processes. Many shivers were shown in the grounded fibers. The amount of shivers was decreased and the single fibers were increased during the process of bleaching. The alkaline pulp and the alkaline bleach pulp showed high in the beating time and freeness than the grounded pulp and grounded bleach pulp. The conditions of sheet surface according to beating time is effected largely by the conditions of original pulp.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.16-25
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• 2014

This study was investigated in optimum condition of pulping of ramie and the mechanical properties of non-woven fabric for the performance of ramie/cotton panty liner. The result of pulping condition on ramie was most suitable for type I (mixed NaOH with $Na_2CO_3$ in 30%:70%). The sample (I) was showed yield value of 68.2% and the best fibrillation and lignin removal rate. The non-woven fabrics of ramie/cotton were made in range of ramie content of 0, 15 and 30%. As ramie content increased, so were increased in air permeability, compressive strength and compression recovery rate. But surface roughness and compressional energy were decreased. Therefore, the non-woven fabrics of ramie/cotton are very suitable in hygienic goods for female panty liner. The ramie panty liner showed a little decrease in absorption and strength, as increasing the amount of ramie. But the performance of ramie panty liner was appeared beyond standard values used by usual panty liner.

• Journal of the Korean Wood Science and Technology
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• v.41 no.5
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• pp.447-455
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• 2013

Hemicellulose extract obtained by pre-pulping extraction of woodchips, is very diluted acidic in nature. The major component responsible for this weak acidity is acetic acid, present in levels up to 5~10 g/L. Here, we report an exploratory study on the extract upgrading by reactive solvent extraction of acetic acid as well as ASPEN simulation. In this study, liquid-liquid equilibria for the ternary systems (water + acetic acid + ethyl acetate) were measured at the temperature of 298.15 K and 10 (pH = 2.02), 5 (pH = 2.17), and 1 (pH = 2.48) percent of acetic acid samples were used to carry out liquid-liquid extraction studies using ethyl acetate. In a one-stage batch experiment, 96.0% of acetic acid could be extracted for the solvent when the ratio of organic-to-aqueous phases is 4:1. For simulation results, they were used to estimate the interaction parameters between each of the three compounds of the systems studied for the NRTL and UNIQUAC models. The estimated interaction parameters were successfully used to predict the equilibrium compositions by the two models.