Surface modified granular activated carbon for enhancement of nickel adsorption from aqueous solution

변상훈,Dhamodaran Kavitha,Kanagasabai Muruganandam Ponvel,Kyung-min Kim,이창하 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.6

Coal-based granular activated carbon was modified with acetates of sodium, potassium and lithium at concentrations of 10 and 15% and used as adsorbents to explore the adsorption mechanism of nickel ion in aqueous solution. Acetate treatment reduced surface area and pore volume of the activated carbons, but the adsorption amount of Ni(Ⅱ) on the modified activated carbons (MAC) was greater than that on the virgin activated carbon. The adsorption depended on pH of the solution with an optimum at 4.5 and the adsorbed nickel could be fully desorbed by using 0.05 M HCl solution. The maximum adsorption capacity of nickel ion on Li (15 wt%) modified activated carbon was 151.3 mg/g and the adsorption isotherm follows Langmuir, Sips, and Redlich-Peterson isotherm models better than the Freundlich isotherm model. The kinetic data was better fitted by a non-linear form of the pseudo-first order than the pseudo-second order, but the difference between two kinetic models was small.

[주제발표 Ⅳ] 사회적기업 성공요인과 극복과제

변상훈 한국농촌경제연구원 2011 한국농촌경제연구원 연구자료 Vol.- No.-

일부 인쇄업 근로자의 유기용제 및 소음 노출에 관한 연구

변상훈,유인성,손종렬 대한환경위생공학회 1998 대한환경위생공학회지 Vol.13 No.3

실내·외 공기 중 휘발성 유기용제 포집을 위한 확산형 시료포집기의 성능변수에 대하여

변상훈 高麗大學校 倂設 保健大學 保健科學硏究所 1999 保健科學論集 Vol.25 No.1

Charcoal-based diffusive organic vapor monitors(OVMs) originally designed for sampling occupational exposures are increasingly being utilized to measure outdoor, indoor, and personal air concentrations of volatile organic compounds(VOCs). There has been very limited evaluation of the performance parameters of OVMs for use in nonoccupational environments where, typically, concentrations of VOCs are more than one order of magnitude lower than those found in usual industrial settings. The results of an extensive laboratory and field evaluation of the 3500 OVM(3M Company, St. Paul, MN, USA) indicate that OVMs can be used in community environments with 48-hour exposure durations with extensive modification of the extraction and analysis procedures. The OVM performance parameters for this type of application are presented, including analytical and method detection limits(MDLs), extraction efficiencies at ㎍-level loading, and optimum sampling times for indoor, outdoor and personal air monitoring in community environments.

대안탐구 : 원주의 협동조합적 사회복지 모델

변상훈 민주화운동기념사업회 2012 계간 민주 Vol.4 No.-

확산 포집기를 이용한 공기중 유기용제 측정에 관한 연구

변상훈 高麗大學校 倂設 保健大學 保健科學硏究所 1997 保健科學論集 Vol.23 No.1

The laboratory and field tests for air monitoring of ethylacetate and toluene were carried by passive sampling methods and compared the results with using charcoal tubes. The results were as follows; 1. The mean desorption efficiencies of A, B passive monitors were over 85%. Those of B passive monitor for ethylacetate, however, had been increased to 17.5% by using the agitator for desorption. 2. The capacities of A, B passive monitor which had been exposed at the 2×STD for 8 hours were increased linearly with time increasing. So, A, B passive monitor were more suitable than charcoal tubes at long time exposure level. 3. As for the back diffusion, A passive monitors showed 8.4% concentration difference for ethylacetate and 5.0% for toluene and B passive monitors showed 1.2% for ethylacetate and 1.3% for toluene, respectively. Both of A, B passive monitors showed less than 10% difference. 4. As for the face velocity, A passive monitor showed less than 10% difference between high and low face velocity. But B passive monitors showed 12.7% difference between high and low velocity. So, they seemed to be affected by face velocity. 5. The uptake difference between low and high humidity showed very low values which were 0.8-3.3% for EAc and 0.1-0.2% for toluene. 6. The precision and accuracy for A, B passive monitors were also checked. The coefficients of variance for A B passive monitors were 2.3-4.0% for A passive monitors and 5.5-9.0% for B passive monitors. Overall accuracies for A passive monitors were ±14.2-14.8% and ±18.5-19.9% for B passive monitors. Overall accuracies for them were below 25% at the 95% confidence level. 7. The results of air monitoring by using passive monitors for ethylacetate and toluene were compared with the results of using charcoal tubes in gravers printing plants. The correlation between charcoal tubes and passive monitors were evaluated as Y=1.76X+37(r=0.81, p<0.05) for ethylacetate and Y=1.36X-49(r=0.93, p<0.06) for toluene.

챔피언 브이 외 1편

변상훈 고요아침 2018 한국동시조 Vol.- No.10

시화공단 지역의 주요 휘발성물질 농도 분포 특성

변상훈,이정근,김정근,Byeon, Sang-Hoon,Lee, Jeong-Geun,Kim, Jeong-Keun 대한환경공학회 2010 대한환경공학회지 Vol.32 No.1

본 연구에서는 시화지구의 공단과 주거 지역에서의 휘발성 유기화합물 농도를 측정하고 그 특성을 비교 분석하였다. 공단지역과 주거지역 21개소에 passive sampler를 1개월간 설치하여 총 6회에 걸쳐 벤젠, 트리클로로에틸렌, 톨루엔, 에틸벤젠, 자일렌과 스티렌을 채취하였다. 그 결과 VOCs 물질 중 톨루엔이 공단지역과 주거지역에서 가장 높은 농도로 검출되었다. 공단지역의 평균 TVOC농도는 주거지역의 1.86배에 해당했으며, 여름철에 비해 겨울철에는 그 농도가 크게 감소하였다. 또한, 평균 BTEX 농도는 공단지역의 화합물의 농도가 주거지역보다 1.94~5.39배 더 높은 것을 보여준다. 에틸벤젠과 자일렌은 여름철에 비교해 겨울철에 농도가 감소하였으나, 벤젠은 더 높은 농도로 측정되었다. VOCs 간의 상관계수는 공단지역에서의 물질간의 상관성이 주거지역보다 좀 더 큰 것으로 나타내었다. 공단지역에서는 대체로 양의 상관성을 보이는 물질들이 주거지역에서는 에틸벤젠과 톨루엔의 경우를 비롯해 음의 상관성을 보였다. 전반적으로, VOCs 농도는 공단지역에서 더 높았으며, 주거지역의 VOCs 분포에 잠재적으로 영향을 미치는 것으로 파악할 수 있다. In this study, we investigated the concentrations of volatile organic compounds (VOCs) in Shiwha area and compared the characteristics of both industrial area and residential area. The passive samplers were set 6 times each for a month in 21 locations at industrial and residential area to obtain 6 VOCs including benzene, trichlorobenzene, toluene, ethyl benzene, xylene and stylene. Above all, toluene was the most abundant VOCs in the ambient air both in industrial and residential area. Average TVOC concentration of industrial area was 1.86 times higher than that of residential area, and it was greatly reduced in winter compared with summer. Furthermore, the average BTEX concentrations showed that all concentrations of industrial area were 1.94~5.39 times higher than those of residential area except benzene which were similar to each other. In winter, the concentration of ethyl benzene and xylene were significantly decreased by comparing with summer: but benzene concentrations were increased. Also, BTEX relative ratio was as follows: toluene>benzene>ethylbenzene>xylene. Correlation coefficients among VOCs were confirmed that VOCs in ambient air of industrial area were generally more related to each other than that of residential area. On the whole, the concentrations of VOCs in industrial area were higher, and it seems to be potential that industrial area affects the distribution of VOCs to residential area.

원저 : 작업환경측정제도 규제 순응 실태

변상훈,이관형,유계묵,피영규 한국산업위생학회 2009 한국산업보건학회지 Vol.19 No.3

국산 확산포집기를 이용한 기중 포름알데히드 농도 측정 및 평가

변상훈,임채현,손종렬 高麗大學校 倂設 保健大學 保健科學硏究所 2002 保健科學論集 Vol.28 No.1

The purpose of this study is to investigate if some formaldehyde exists in DONG DAE MOON cloth or dry goods markets, and also to alalyze the function of sampler on the hypothesis that are some formaldehyde in those places. More importantly we did not use the existing method by active sampler but we used the new diffusive sampler that we made. 1. The result of this study showed that some formaldehyde existed in DONG DAE MOON cloth and dry goods markets. Average concentration of formaldehyde was 0.136ppm 2. On the basis that the ministry of labor in Korea recommended the Permissible Exposure Limit(PEL) as 0.1ppm, the value of 0.136ppm exceed the PEL. In conclusion, more many stydies about how formaldehyde effects on human body and what diseases that material cause in the body should be proceeded in addition more stydies using diffusive sampler will be needed in the future