• 한국물환경학회지
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• 제21권6호
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• pp.549-563
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• 2005

The study was carried out to develop and standardize the analytical method of 1,4-dioxane in water. The National Institute of Environmental Research in Korea has monitored for 1,4-dioxane in water since 1998 and it has been detected in environmental water occasionally. But the environmental pollution and analytical method in water is not well known over the world. The trace analytical method at low-${\mu}/L$ level is prerequisite in order to evaluate the residue of 1,4-dioxane in water. Evaluation of the method was demonstrated by comparing and analyzing with liquid-liquid extraction, solid-phase extraction and purge & trap technique. As a result of experiment by standard solutions and raw samples, the precision and accuracy for three methods were obtained within error rate of about 10%. Therefore, three methods were standardized as official monitoring method in Korea. Also, a convenient and simple liquid-liquid extraction method for the analysis of 1,4-dioxane in water was developed by combined with gas chromatography/mass spectrometry and applied to the water samples in Korea

• Journal of the Korean Wood Science and Technology
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• 제12권4호
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• pp.19-30
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• 1984

This experiment was carried out to investigate the effects of autohydrolysis and extraction conditions on the separation of the chemical substances, the extractability of lignin by dioxane, and the yield of reducing sugars from cellulosic substrates by using a commercial cellulase derived from Trichoderma viride. Air-dried wood meals through 0.42mm (40 mesh) screen and retained on 0.25 mm (60 mesh) of Populus alba-glandulosa and Pinus koraiensis were autohydrolyzed with water at $180^{\circ}C$ for 30 and/or 60 minutes in a 6 liter stainless-steel digester with or without 2% 2-naphthol. The hydrothermally-treated wood meals were extracted the lignin with 100%, 90%, 75% and 50% dioxane solutions at $70^{\circ}C$ for 4 hours, respectively. The results obtained were as follows; 1) After autohydrolysis of Populus alba-glandulosa, the yield of wood meals decreased with lengthening the auto hydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. In case of Pinus koraiensis, the yield was not affected by 2%, 2-naphthol addition at the autohydrolysis in the digester. 2) After autohydrolysis and lignin extraction of Populus alba-glandulosa, the yield of wood meals decreased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. Extraction of 50% dioxane solution was the best solvent for the yield among the solutions of 100%, 90%. 75% and 50% dioxane. In case of Pinus koraiensis, the yield was not affected by 2% 2-naphthol addition and the solution of 90% dioxane was the poorest solvent for the yield. 3) After autohydrolysis and lignin extraction of Populus alba-glandulosa, the Klason lignin content in cellulosic substrates for enzymatic hydrolysis decreased with lengthening the autohydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. Klason lignin content was the lowest after extraction by 90% or 75% dioxane solution. The content was also affected by interaction of the three factors-autohydrolysis time, 2% 2-naphthol addition and concentration of dioxane. In case of Pinus koraiensis, the Klason lignin content increased with 2% 2-naphthol addition but was not affected by the concentration of dioxane solution. 4) After autohydrolysis and lignin extraction of Populus alba-glandulosa, the extractable Klason lignin content by extraction increased with lengthening the auto hydrolysis time from 30 minutes to 60 minutes and with 2% 2-naphthol addition. The extractable lignin content was the highest after extraction by 90% or 75% dioxane solution. In case of Pinus koraiensis, the extractable lignin content increased with 2% 2-naphthol addition. Extractions by 100%, 90% and 50% dioxane solutions were more effective for the extraction of Klason lignin than by 75% dioxane solution. 5) After autohydrolysis and lignin extraction of Populus alba-glandulosa, the yield of reducing sugars increased with lengthening the autohydrolysis time from 30 minutes to 60 minutes but was not affected by 2% 2-naphthol addition and the concentration of dioxane. The yield of reducing sugars after enzymatic hydrolysis was slightly higher by extractions with 90%, 75% and 50% dioxane solutions than with 100% dioxane. In case of Pinus koraiensis, the yield of reducing sugars was not affected by 2% 2-naphthol addition but affected by the concentration of dioxane. The yield of reducing sugars was the highest in cellulosic substrates extracted by 100% dioxane solution.

• Environmental Analysis Health and Toxicology
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• 제18권3호
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• pp.219-224
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• 2003

1,4-Dioxane is used as a solvent for lacquers, paints, varnish removers, dye baths and printing compositions. And it is also used for detergent preparations, cosmetics, deodorants and fumigants. A method is described for the determination of 1,4-dioxane in water samples by GC/MS. The extraction recoveries were studied for some solvents and solvent volume ratio were investigated using r-butyl methyl ether (MTBE). Optimum condition was obtained by the liquid-liquid extraction using the 10 mL of MTBE for 10 mL of water. Method detection limit of 1,4-dioxane in the 20 mL of water samples was 0.05 ng/mL. It could be determined in the range of 0.24∼240 ng/mL in treated water, and in the range of 0.69∼81.9 ng/mL in raw water, respectively. Risk assessments with 1,4-dioxane exposure by drinking water ingestion were carried out. Based on the results of analysis, chronic daily intake of 1,4-dioxane was 2.22${\times}$10$\^$-4/ mg/kg/day and excess cancer risk was calcu-lated to be 2.44${\times}$10$\^$-6/.

• 분석과학
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• 제18권2호
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• pp.154-162
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• 2005

최근 국내 일부 정수장에서 검출된 것으로 보도되어진 바 있어 우리나라의 하천 수의 오염이 우려되고 있고, 일부 오염정도가 높은 하천수의 정화과정에서 제거가 완전히 이루어지지 않는 것으로 사료되는 1,4-dioxane은 그 독성과 음용수의 섭취량을 고려할 때 음용수 섭취로 인한 인체효과가 문제화 될 것으로 판단된다. 따라서 본 연구에서는 활성탄과 멤브레인으로 구성된 다단계 필터시스템에서 음용수 중에 존재하는 1,4-dioxane에 대한 제거효과에 대하여 연구하였다. 확인방법은 MTBE을 이용한 액체-액체 추출방법을 사용하였으며 제거실험은 압력별 필터단계별로 30 L마다 300 L 까지 실시하였다. 그 결과 초기에는 1차 활성탄 필터이후 70% 이상의 제거효과를 나타내었으며 멤브레인 이후 95%이상 그리고 2차 활성탄 이후 100% 제거되는 결과를 나타내었다. 그러나 통수량이 증가할수록 각 단계별 제거율은 점차 감소하였으며 300 L 통수 후 1차 활성탄에서 30%, 멤브레인 이후 88% 그리고 최종 활성탄 이후 99%의 제거율을 나타내었다.

• 분석과학
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• 제27권1호
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• pp.22-26
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• 2014

1,4-dioxane은 국제 암연구소에서 2B의 발암물질로 분류하고 있는 물질이다.지표수 중에 1,4-dioxane을 headspace gas chromatographic mass spectrometry에 의해 측정하였다. 시료 5 mL를 10 mL 헤드스페이스 vial에서 넣고 NaCl로 포화시킨 후 내부표준물질로 1,4-dioxane-d8 첨가한 후 $90^{\circ}C$에서 30분간 가열하였다. 위의 방법을 사용하여 금강 22개 지점에서 2012년 6월과 9월 시료 채취하여 분석한 결과 $0.49-43.0{\mu}g/L$ (평균 $2.0{\mu}g/L$)의 범위로 약 30%의 빈도로 검출되었다.

• 펄프종이기술
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• 제42권4호
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• pp.64-70
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• 2010

In this study, hemicelluloses were pre-extracted from mixed hardwood chips using sodium hydroxide solution and then they were isolated from pre-extractives by using various solvents. Isolation was conducted by precipitating hemicelluloses with isopropanol, ethanol, 1,4-dioxane, dimethylsulfoxide (DMSO) and potassium hydroxide (KOH), respectively. The precipitate yield on alkali pre-extractives was the highest when hemicelluloses were isolated by DMSO and then precipitated with ethanol. Most precipitates were yellow colored. The efficiency of isolation was evaluated by analysing the characteristics of isolated hemicelluloses. Isolation using DMSO, KOH and 1,4-dioxane ($80^{\circ}C$) showed rather high efficiency. The highest total separation efficiency was about 77% when alkali pre-extractives were reacted with KOH and precipitated with ethanol. The quantity and purity of isolated hemicelluloses were affected by the solvent type.

• 분석과학
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• 제8권4호
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• pp.511-517
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• 1995

A cationic water soluble porphyrin (5,10,15,20-tetrakis (l-methyl-pyridinium-4-yl)porphyrin, $H_2tmpyp^{4+}$) and its metalloporphyrins (MP) were easily extracted into acetonitrile separated by addition of sodium chloride ($4mol\;dm^{-3}$) in the presence of sodium perchlorate, where M denotes $Zn^{2+}$, $Cu^{2+}$, $Co^{3+}$, $Fe^{3+}$, and $Mn^{3+}$ and $P^{2-}$ is porphyrinate ion. The extracted ion-pair complexes were completely dissociated to $[MP(ClO_4)_3]^+$, and $[MP(ClO_4)_2]^{2+}$. The extraction and the dissociation constants were determined by taking into account of the partition constant of sodium perchlorate ($K_D=1.82{\pm}0.01$). The chemical properties of the separated acetonitrile phase as $E_{T(30)}$ and $D_{II,I}$ were determined and compared with other water miscible solvents (acetone, actonitrile, 1,4-dioxane, tetrahydrofuran, 1-propanol and 2-propanol). Furthermore, a sensitive and selective method was proposed for the determination of a subnanogram amount of copper(II) in natural water samples by using the present salting-out method and the porphyrins.

• 분석과학
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• 제25권4호
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• pp.236-241
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• 2012

낙동강 수계는 중 상류 지역에 대규모 공단이 입지하고 있어 그동안 phenol, 1,4-dioxane, perchlorate 등 유해물질에 의한 수질오염사고가 많이 발생하였다. 본 연구에서는 낙동강 수계에 유출 가능성이 있는 미규제 유해물질 중 반휘발성유기화합물질(semi-volatile organic compoumsds, SVOCs) 10종(dichlorvos, toluene-2,4-diisocyanate, 4,4'-methylenedianiline, 4,4'-methylenebis(2-chloroaniline), diethyl phthalate, di-n-butyl phthalate, butyl benzyl phthaltate, bis(2-ethylhexyl)adipate, benzophenone, 4,4'-bisphenol A)에 대하여 디스크형 고상 추출법과 GC/MS를 이용하여 분석하였으며, 정확도 75.6~110.5%, 정밀도 4.6~12.7%, 회수율 72.4~127.9%의 결과를 얻을 수 있었다. 낙동강 수계에 위치한 하 폐수처리장 및 폐수배출업소 등 공장폐수 시료를 분석한 결과 bis (2-ethylhexyl)adipate, benzophenone, 4,4'-bisphenol A 등 3개 물질이 검출되었다.

• 한국식품영양과학회지
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• 제32권7호
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• pp.965-970
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• 2003

폴리소르베이트류, 염화콜린, 주석산수소콜린, 변성전분 및 향신료 중 1,4-디옥산 및 클로로히드린류의 분석법을 개발하고 확립된 방법으로 잔류량을 조사한 결과는 다음과 같다. 분석에 사용된 트랩으로는 Vocarb 3000이 적합하였고 이때의 검출한계는 DOX 1.38$\mu\textrm{g}$, EPC 0.23$\mu\textrm{g}$, PCH 3.30$\mu\textrm{g}$, ECH 3.97$\mu\textrm{g}$, DCP 20.43$\mu\textrm{g}$이었다. 검체 온도증가와 무수황산나트륨 농도 증가에 따라 분석감도는 증가하였으나 6$0^{\circ}C$ 이상에서는 상대표준편차(RSD, %)가 6%를 초과하여 재현성이 떨어져 분석온도를 5$0^{\circ}C$로 설정하였다. 폴리소르베이트류에서의 회수율은 염을 첨가하지 않고 측정하였을 때 EPC(66%)를 제외하고는 90%이상을 나타내었다. 염화콜린 및 주석산수소콜린의 경우에는 대부분 회수율이 100% 이상이었으나 주석산수소콜린의 EPC는 20%로 낮게 나타났다. 히드록시프로필인산이전분, 히드록시프로필전분 및 찰옥수수전분에서는 검체를 가수분해한 후 회수율을 측정한 결과 검체종류별 큰 차이 없이 회수율이 90% 이상을 나타내었다. 향신료의 분석에서는 무수황산나트륨을 첨가하여 분석한 결과 회수율이 90%이상이었다. 구매한 폴리소르베이트류, 염화콜린, 주석산수소콜린, 향신료 중 1,4-디옥산 및 클로로히드린류를 분석한 결과 트윈 80에서 DOX가 2.5ppm 검출되었으나 이외의 검체에서는 모두 불검출되었고 직접 제조한 히드록시프로필전분에서도 모두 불검출되었다.

• 임산에너지
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• 제17권1호
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• pp.56-70
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• 1998

This study was carried out to investigate the structural characteristics of kraft lignin and the wood degrading characteristics, the productivity of ligninolytic enzymes and the enzymatic degradation of kraft lignin by white-rot fungi. To purify kraft lignin, precipitation of kraft pulping black liquors of pitch pine meal was done by titration with lN $H_{2}SO_{4}$ reaching to pH 2, and isolation of the precipitates done by centrifugation. The isolated precipitates from pitch pine were redissloved in lN NaOH, reprecipitated by titration with lN $H_{2}SO_{4}$, washed with deionized water, and kept ofr analysis after freeze drying. Fractionation of the precipitates in solution by successive extraction with $CH_{2}Cl_{2}$ and MeOH, and the fractionates were named SwKL, SwKL I, SwKL II, and SwKL III for pitch pine kraft lignin. The more molecular weights of kraft lignin increased, the less phenolic hydroxyl groups and the more aliphatic hydroxyl groups. Because as the molecular weights increased, the ratio of etherified guaiayl/syringyl(G/S ratio) and the percentage were increased. The spectra obtained by 13C NMR and FTIR assigned by comparing the chemical shifts of various signals with shifts of signals from autherized ones reported. The optimal growth temperature and pH of white-rot fungi in medium were $28^{\circ}C$ and 4.5-5.0, respectively. Especially, in temperature and pH range, and mycelial growth, the best white-rot fungus selected was Phanerochaete chrysosporium for biodegradation. For the degradation pathways, the ligninolytic fungus jcultivated with stationary culture using medium of 1% kraft lignin as a substrate for 3 weeks at $28^{\circ}C$. The weight loss of pitch pine kraft lignin was 15.8%. The degraded products extracted successively methoanol, 90% dioxane and diethyl ether. The ether solubles were analyzed by HPLC. Kraft lignin degradation was initiated in $\beta$-O-4 bonds of lignin by the laccase from Phanerochaete chrysosporium and the degraded compounds were produced from the cleavage of $C\alpha$-$C\beta$ linkages at the side chains by oxidation process. After $C\alpha$-$C\beta$ cleavage, $C\alpha$-Carbon was oxidized and changed into aldehyde and acidic compounds such as syringic acid, syringic aldehyde and vanilline. And the other compound as quinonemethide, coumarin, was analyzed. The structural characteristics of kraft lignin were composed of guaiacyl group substituted functional OHs, methoxyl, and carbonyl at C-3, -4, and -5 and these groups were combinated with $\alpha$ aryl ether, $\beta$ aryl ether and biphenyl. Kraft lignin degradation pathways by Phanerochaete chrysosporium were initially accomplished cleavage of $C\alpha$-$C\beta$ linkages and $C\alpha$ oxidation at the propyl side chains and finally cleavage of aromatic ring and oxidation of OHs.