• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.1067-1070
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• 2012

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1995년도 제47차 추계 학술대회 연제집
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• pp.365-366
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• 1995

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1997년도 추계총회 및 학술발표회 논문집
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• pp.55-60
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• 1997

• 청정기술
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• 제19권4호
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• pp.487-491
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• 2013

Dowex21K XLT 수지에 흡착된 금과 구리-시안 착화합물을 효과적으로 탈착시키기 위하여 쌍극성의 반 양성자성 용매의 일종인 아세톤을 염산과 섞은 혼합용매를 탈착제로 이용하였다. 염산과 아세톤의 혼합비율(부피비)이 7:3일 때 금-시안 착화합물의 탈착율은 약 94%로서 가장 높았으나 아세톤의 비율이 증가할수록 금-시안 착화합물의 탈착율은 감소하였다. 구리-시안 착화합물의 경우는 염산의 비율이 아세톤의 비율보다 상대적으로 높았을 때 거의 대부분을 탈착시켰으나 아세톤의 비율이 증가할수록 탈착율은 감소하였다. 또한, 0.6 M의 염산을 사용하였을 때(염산과 아세톤의 혼합비율은 7:3으로 고정) 금과 구리-시안 착화합물의 탈착율은 각각 94%와 100%였으며 더 높은 염산 농도를 사용하여도 금-시안 착화합물의 탈착율은 증가하지 않았다. 그리고 고체와 액체의 비(ratio of solid and liquid)가 1.0보다 작을 때는 금과 구리-시안 착화합물 모두 100%의 탈착율을 보여주었으나 1.0보다 클 때에는 금-시안 착화합물의 탈착율이 약 20~29%로서 아주 낮았다. 또한, 금과 구리-시안 착화합물에 대한 대부분의 탈착공정은 120분 내에 이루어졌다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.719-724
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• 2001

The objective of this investigation was to separate silicon and silica for recycling by the liquid-liquid separation technique. In the preparation of silicon (Si) single crystal, a small amount of silicon is fixed on the surface of silica (quartz, $SiO_2$) crucible. The used crucible is crushed for recycling both silicon and silica in a high purity from the mixed powder. Zeta-potential of silicon and silica are almost the same at pH higher than 3. Their separation by simple flotation is ruled out. However, their hydrophobic characteristics are different in several different organic solvent from the measurement of contact angle. Therefore, the liquid-liquid extraction is employed to separate silicon and silica. The result indicates that the organic solvent mixed with dodecyl ammonium acetate could extracted the silicon powder at high purity (97-100%) with high recovery from the silica powder in the water phase.

• 한국환경보건학회지
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• 제24권2호
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• pp.80-87
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• 1998

To evaluate the effects on health by exposure to low dose organic solvents, the author analyzed the air concentration of mixed organic solvents (toluene, xylene, butylacetate) at worker's breathing zone during painting, some laboratory findings of blood (WBC, RBC, Hb, Hct, SGOT, SGPT, TC, TG, HDL-C, LDL-C, IgG, IgM, IgA and IgE) and urine (hippuric acid, urinary protein, urobilinogen), surveyed the subjective symptoms those were obtained from 35 male workers exposed to mixed organic solvents, and 25 male workers not exposed to organic solvents who worked in car repair workshops in Taejon area from December 1, 1995, to February 29, 1996. The results were as follows: 1. The mean concentration of urinary hippuric acid of car painting worker group (organic solvent exposure group) was 0.76$\pm$ 0.21 g/l, which is significantly higher than that of non-exposed group. 2. In hematologic findings, the values of RBC, TC, LDL-C, IgG and IgE in the exposure group were significantly lower than those of the nonexposed group, but SGOT and SGPT in the exposure group were significantly higher than those of the non-exposed group. 3. Urinary hippuric acid levels showed positively correlated with toluene, urobilinogen and HDL-C levels, but those were negatively correlated with RBC, LDL-C, IgM levels. 4. Rates of the subjective symptoms such as "dizziness", "appetite loss", "weight loss", "palpitation", "chest tightness", "sore throat and eye discomfort", "tingling sense and acrodynia", "illusion or hallucination" and "decreaased motor power" were significantly higher in the exposure group than those of the non-exposed group.

• 한국의류산업학회지
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• 제8권2호
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• pp.233-238
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• 2006

This research confirmed the chemical structure of Curcumine and Carthamin pigments whose pigments were separated and refined from the Curcuma longa and Carthamus Tinctorious which were natural dye using FT-IR, HPLC and so on. The cotton and the silk fabrics were dyed using a main pigment and then this research obtained the conclusion as it follows. The curcumine, the main pigment of Curcuma longa extracted from the mixed solvent of acetic anhydride and methanol ($CH_3OH$), had the maximum absorption wavelength at 504.0 nm and was confirmed as yellow natural pigment. The Carthamin, the main pigment of Carthamus Tinctorious extracted from the mixed solvent of dichloromethane and methanol, had the maximum absorption wavelength at 420.0nm. This pigment was confirmed as yellow natural pigment. The dyeing property of the main pigment about the silk fabrics was superior to that about the cotton in both the Curcuma longa and Carthamus Tinctorious, and the dyeing property of Carthamus Tinctorious was superior to that of Curcuma longa.

• 자원리싸이클링
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• 제20권2호
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• pp.60-66
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• 2011

염화루테늄 용액에서 루테늄의 분리 및 회수를 위한 기초 연구로 TBP 및 Cyanex923을 이용하여 루테늄의 용매추출 거동을 조사하였다. 루테늄의 추출율에 영향을 미칠 수 있는 수용액상의 염산농도 및 염소이온 농도, 유기상의 추출제 농도, 온도 등에 대해서 고찰하였고, 유기상으로 추출원 루테늄의 탈거거동에 대해서도 조사하였다. 또한 백금, 비스무스, 납, 구리, 철, 주석 등과의 혼합용액에서 염산농도에 따라 각 성분들의 추출거동을 조사하였다. 실험결과 루테늄의 추출을 위해서는 Cyanex923이 효과적이었다. 그러나 TBP를 사용할 경우 루테늄의 추출율은 낮으나 백금, 비스무스, 주석 등의 불순물을 제거하는 데는 효과적이었다.

• 분석과학
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• 제20권6호
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• pp.496-501
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• 2007

ICP-AES를 이용하여 금을 분석할 때 감도가 가장 우수한 242.795 nm 파장은 분광학적 간섭을 일으키는 망간, 크롬, 코발트, 철 등의 원소들 때문에 광물에서 금의 분석은 불가능하다. 여기에서는 이들 원소들을 정량적으로 분리하는 분리방법을 연구하였다. 광물에서 금을 분리하기 위하여 광물을 용해한 산 용액에 MIBK 용매를 사용하여 정량적으로 추출하였다. 이때 질산과 염산의 혼산과 MIBK/n-hexane의 혼합용매는 효율적으로 금을 추출할 수 있었으며, 회수율은 97.5% 이상이었다.

• Annals of Occupational and Environmental Medicine
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• 제35권
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• pp.11.1-11.17
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• 2023

Background: Studies on the relationship between organic solvent exposure and chronic kidney disease (CKD) have presented inconsistent results. Definition of CKD has changed in 2012, and other cohort studies have been newly published. Therefore, this study aimed to newly confirm the relationship between organic solvent exposure and CKD through an updated meta-analysis including additional studies. Methods: This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The search was conducted on January 2, 2023 using Embase and MEDLINE databases. Case-control and cohort studies on the relationship between organic solvent exposure and CKD were included. Two authors independently reviewed full-text. Results: Of 5,109 studies identified, a total of 19 studies (control studies: 14 and cohort studies: 5) were finally included in our meta-analysis. The pooled risk of CKD in the organic solvent exposed group was 2.44 (1.72-3.47). The risk of a low-level exposure group was 1.07 (0.77-1.49). The total risk of a high-level exposure group was 2.44 (1.19-5.00). The risk of glomerulonephritis was 2.69 (1.18-6.11). The risk was 1.46 (1.29-1.64) for worsening of renal function. The pooled risk was 2.41 (1.57-3.70) in case-control studies and 2.51 (1.34-4.70) in cohort studies. The risk of subgroup classified as 'good' by the Newcastle Ottawa scale score was 1.93 (1.43-2.61). Conclusions: This study confirmed that the risk of CKD was significantly increased in workers exposed to mixed organic solvents. Further research is needed to determine the exact mechanisms and thresholds. Surveillance for kidney damage in the group exposed to high levels of organic solvents should be conducted.