• Title, Summary, Keyword: Alkali Treatment

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Increase in Color Depth of Polyester Fiber by Alkali Treatment and Analysis of the Surface Structure (알칼리 감량에 의한 폴리에스테르 섬유의 심색화와 표면구조분석)

  • 김태경;임용진;석정달;조광호
    • Textile Coloration and Finishing
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    • v.11 no.5
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    • pp.22-29
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    • 1999
  • The increase in color depth of polyester fiber dyed with black disperse dyes was investigated with respect to the kinds of resins and alkali treatment. The color depth of the dyed polyester fiber increased continuously according to the concentration of resins coated onto the fabrics. The alkali treatment to polyester fiber before dyeing also enhanced the color depth. It was thought that the polyester fiber was hydrolyzed by alkali resulting micropores on the sample. And the following treatment with a resin, Jet Black T-101, to the polyester fiber increased the color depth much higher. The successive process of alkali treatment, dyeing and Jet Black T-101 treatment could give the best color depth to polyester fiber. Although the alkali treatment reduced the tensile strength of polyester fiber, the color depth of polyester fiber enhanced sufficiently within the range of practically acceptable weight loss and strength. To analyze the micropore on the polyester fiber formed by alkali treatment, nitrogen porosimeter was used. As the weight loss of polyester fiber treated with alkali increased, the BET(Brunauer-Emmett-Teller) surface area, total pore volume, and average pore size of the sample increased.

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CHEMICAL COMPOSITION OF WHEAT STRAW AS INFLUENCED BY UREA AND ALKALI TREATMENTS AT DIFFERENT MOISTURE LEVELS

  • Rasool, E.;Gilani, A.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.6
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    • pp.563-566
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    • 1995
  • To improve the nutritive value of wheat straw it as treated with 0, 3, 4 and 5 percent levels of urea, 0 and 4 percent level of alkali at 40, 50 and 60 percent moisture levels and stored at room temperature. Total nitrogen contents of the straw increased significantly, from 0.77 percent with no urea treatment to 0.87, 1.16 and 1.19 percent with 3, 4 and 5 percent urea levels, respectively. Percent retention of nitrogen was 63.73 percent. Alkali treatment at 4 percent level, lowered significantly the crude fibre contents of the straw from 41.86 percent in control to 40.21 percent in the treated straw. Moisture level of 40 percent significantly lowered (p < 0.05) the crude fibre contents. Total ash content of straw increased significantly by urea and alkali treatment. Alkali treatment improved significantly the sodium contents also. The results of the study indicated that most beneficial results were obtained with 4 percent urea, 4 percent alkali at 50 percent moisture level.

Effect of Stretching on Cellulose Fiber Swelling in Alkali Aqueous Solutions (알칼리수용액안에서 셀룰로오스섬유가 팽윤할 때 장력이 미치는 영향)

  • 최철호
    • Textile Coloration and Finishing
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    • v.4 no.3
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    • pp.91-96
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    • 1992
  • The crystalline character of NaOH and KOH-cellulose complex having different tension ratio was studied using X-ray diffraction analysis. Cellulose crystalline lattices in tension alkali treatment cotton were identified by measuring and indexing the 101, 101, and 002 reflections. According as alkali treatment tension ratio increased on, cellulose gave rise to the formation of I rather than cellulose II. It seemed that a part of the fine structure of cellulose increased orientation with antiparaell and parallel chain crystal structure. The high tension ratio alkali treatment cotton resulted in lower dye sorption and in higher breaking strength and crease recovery.

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Conversion of Woody Biomass for Utilization(III) - The Preparation of Dissolving Pulp by Oxygen·Alkali Method from Exploded Wood - (목질계 Biomass의 변환 이용(III) - 폭쇄처리재의 산소·알칼리법에 의한 용해용 펄프의 제조 -)

  • Lim, Bu-Kug;Yang, Jae-Kyung;Lee, Jong-Yoon
    • Journal of the Korean Wood Science and Technology
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    • v.25 no.4
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    • pp.68-74
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    • 1997
  • This research was studied dissolving pulp for rayon production, which is not KP, SP methods but steam explosion and oxygen alkali treatment. The variation of characterization in wood cellulose after steam explosion and oxygen alkali treatment this follows. In the oxygen alkali treatment of exploded pine wood, yield of dissolving pulp was lower than steam-exploded oak wood, and we have obtained dissolving pulp that high purity cellulose, but degree of polymerization was inclined to decrease less than 200. In the case of steam-exploded oak wood, degree of polymerization was higher than steam-exploded pine wood but purity of cellulose was lower than its.

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Effect of Color Developing by Alkali and Heating of Cotton Fabrics Dyed with Persimmon Extract (알칼리와 열처리에 의한 면직물의 감즙염색 발색효과)

  • Kim, Ok-Soo;Jang, Jeong-Dae
    • Fashion & Textile Research Journal
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    • v.13 no.6
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    • pp.972-982
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    • 2011
  • The purpose of this study is to improve the method of color developing with alkali solution as a promotor of color developing for feasible use. Cotton fabric was dyed with persimmon extract ranged with 0~3% alkali component with 5 types of strong to mild alkali solution. Heat treatment for color developing was applied to fabric dyed with persimmon extract and alkali mixing solution. Tests were carried out to analyze the change of surface color, ${\Delta},Ea^*b^*$, and water repellent of the dyed cotton fabric. The alkali mixing sample showed higher ${\Delta},Ea^*b^*$ value than control one without alkali mixing on the base of dyed fabric due to high color developing by alkali in the initial step of dyeing process. As alkali concentration increased, deeper dark color appeared on the fabric. The fabric color was changed to more dark in the application of sodium hydroxide, sodium carbonate, potassium carbonate in the initial step of dyeing process but color was not changed by increased heating time. However, the fabric showed a slight dark color with sodium acetate and more color change than that of the fabric dyed with persimmon extract without alkali. Therefore, sodium acetate seemed to a suitable promotor for color developing in persimmon extract dyeing. Property of water repellent was showed after color developing by heating with low concentration of alkali treatment.

Changes in Fiber Characteristics by Low Concentration Sodium Hydroxide Swelling and Beating (저농도 NaOH 팽윤과 고해에 따른 섬유특성 변화)

  • Kim, Ah-Ram;Choi, Kyoung-Hwa;Cho, Byoung-Uk
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.46 no.3
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    • pp.65-72
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    • 2014
  • In this study, effects of alkali swelling at low concentration below 2 percent on properties of hardwood bleached kraft pulp (HwBKP) were elucidated. Swelling treatment of HwBKP was performed at various NaOH concentrations with/without beating. Then, the swelling characteristics of pulp fiber was evaluated by measuring the solvent retention values such as water retention value (WRV) and isopropyl alcohol retention value (LRV). It was found that fiber characteristics were influenced by NaOH swelling even at low alkali concentration and beating treatment as well. The values of WRV and LRV were decreased when the alkali concentration was increased. It is the result from the decreased acidic groups of pulp which were formed during beating. The acidic groups could be neutralized and then removed by alkali. The difference between WRV and LRV was decreased with increasing alkali concentration while the difference was increased when the alkali swollen pulp was beaten. In addition, the crystalline structure of HwBKP was almost not changed while the crystallinity was influenced by swelling treatment at a low alkali concentration.

Effects of Ar-Plasma Treatment in Alkali-Decomposition of Poly(ethylene terephthalate)

  • Seo, Eun-Deock
    • Macromolecular Research
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    • v.11 no.5
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    • pp.387-392
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    • 2003
  • The ablation effects of Ar-plasma treatment and alkali-decomposition behavior in NaOH solution of polyethylene terephthalate (PET) film were investigated. The modifications were evaluated by analysis of atomic force microscopy topographical changes, and by the measurement of decomposition yield in conjunction with heats of formation and electron densities of acyl carbon calculated by Parameterization Method 3 method. It has shown that the alkali-decomposition is hampered by plasma treatment and its decomposition yield is closely related with plasma treatment conditions such as exposure time to plasma. Plasma-treated PET films exhibited lower decomposition yield, compared to that of virgin PET. Increasing plasma exposure time contributes positively to decrease the decomposition yield. It has also shown that the topography of PET surface was affected by the base-promoted hydrolysis as well as Ar-plasma treatments. These behaviors are attributed to the decreased nucleophilicity of acyl carbon damaged by the ablation of Ar-plasma.

Studies on the Enzymatic Hydrolysis of Lignocellulosic Materials for the Alternative Fuels (II) - The Effect of Delignification Treatment on the Enzymatic Hydrolysis of Steam - Exploded Woods - (대체연료(代替燃料) 생산(生産)을 위한 목질재료(木質材料)의 가수분해(加水分解)에 관한 연구(硏究)(II) - 탈(脫)리그닌처리가 폭쇄처리재(爆碎處理材)의 효소적(酵素的) 당화(糖化)에 미치는 영향(影響) -)

  • Cho, Nam-Seok
    • Journal of the Korean Wood Science and Technology
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    • v.18 no.4
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    • pp.18-25
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    • 1990
  • As polysaccharides in lignocellulosic materials are encrusted with aromatic lignin molecules and have high crystallinity, these require pretreatment to improve their digestability by cellulolytic enzymes. Though a number of pretreatment methods have been proposed, the steam explosion process is evaluated as a promising method. This study was performed to investigate the effect of delignification treatment by alkali, methanol and the others on the enzymatic hydrolysis. Delignification treatment resulted in great increase rate in enzymatic hydrolysis. Concerning to the effect of delignication reagents on the enzymatic hydrolysis, methanol treatment was more effective than alkali in the case of oak wood. In pine wood, the delignification did not showed any significant enhancement of hydrolysis rate. Complete delignification by Alkali-Oxygen. Alkali treatment showed high saccharification rate of 99.5%.

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Removal of Pb2+ ion from aqueous solution Using crab shell treated by acid and alkali (산-염기 처리한 게 껍질에 의한 수풍의 납 이온 제거)

  • 김동석
    • Journal of Environmental Science International
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    • v.12 no.4
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    • pp.469-476
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    • 2003
  • In order to examine the pre-treatment effect of crab shell en Pb$^{2+}$ removal by crab shell in aqueous solution, acid and alkali pre-treated crab shell were used. Electron microscopy techniques such as TEM (transmission electron microscopy) and SEM (scanning electron microscopy), and EDX (energy dispersive X-ray) and FTIR (Fourier transform infrared) spectrometry techniques were used to investigate the process of Pb$^{2+}$ removal by acid and alkali pre-treated crab shell. The Pb$^{2+}$ removal by acid pre-treated crab shell was much lower than that by untreated crab shell because of the decrease of CaCO$_3$ from the crab shell. However, the Pb$^{2+}$removal by alkali pre-treated crab shell increased compared to that by untreated crab shell. The results were confirmed by TEM, SEM, EDX and FTIR.nd FTIR.

Surface Treatment Technology for Metal Corrosion Layer Focusing on Copper Alloy

  • Yang, Eun-Hee;Han, Won-Sik;Choi, Kwang-Sun;Lee, Young-Hoon;Ham, Chul-Hee;Hong, Tae-Kee
    • Journal of the Korean Applied Science and Technology
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    • v.31 no.2
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    • pp.176-182
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    • 2014
  • Using alkali treatment solution, neutrality treatment solution and acid treatment solution, the surface corrosion layer of copper plates and bronze plates that have been artificially corroded using HCl, $H_2SO_4$ and $HNO_3$ solutions were removed. In the case of alkali treatment solution, only air oxidation in the form of black tenorite and white cuproous chloride remained without being removed. In the case of using a neutrality treatment solution, a anhydrous type layer of reddish brown cupric chloride remained without being removed, together with this black and white corrosion substance. In the case of using an acid treatment solution, this red corrosion substance also remained, but all of the oxide was removed on the surface of the specimen that was treated by alternatively using alkali treatment solution and acid treatment solution. In the case of this treatment solution with the order of alkali-acid, oxidation no longer proceeded only through the distilled water cleaning process after treatment, thereby showing that oxidation from the cleaning solution no longer proceeded.