• Applied Chemistry for Engineering
• /
• v.26 no.6
• /
• pp.648-658
• /
• 2015

Extraction of phytoncide oil from korea pine cone waste without damaging the pine cone tree itself was investigated using a steam distillation method. Also various components in the extracted phytoncide oil were separated using a column chromatography method. The extraction of phytoncide oil was effectively proceeded, and the maximum production yield of phytoncide oil could be obtained under $100^{\circ}C$ of distillation temperature and within 30 minute of distillation time. According to chemical analysis, it was found that the phytoncide oil from korea pine cone waste was consisted of more than 12 components such as ${\alpha}$-pinene, ${\beta}$-pinene, D-limonene, as main components. In addition, the aqueous hydrogel containing other components such as verbenone, ${\alpha}$-terpinieol, fenchol, different from components of phytoncide oil itself could be obtained through the steam distillation.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1996.03a
• /
• pp.91-109
• /
• 1996

막에 의한 유기액체 혼합물을 분리 하는 방법으로 액/증기 계의 막투과 메카니즘으로 분리, 농축하는 투과증발법(Pervaporation)이 연구되어져 왔다. 이 방법은 공급상이 수용액, 투과상이 기체로써 상변화를 동반하는 과정이기 때문에 분리의 에너지 효율은 증류법에 비해 그다지 높게 기대 되지 않지만 공비점(azotropic point)을 가지는 혼합물이나 비점차가 적어 분해하기가 쉽고 증류법이 불가능한 혼합물의 분리에 많이 쓰여져 왔다. 그러나, 이 방법을 실용화 시키기 위해서는 분리계수 및 투과속도가 큰 막이 필요로 하며 현재 그 연구 개발에 박차를 가하고 있다. 본 강의는 무기재질을 가지는 다공성막을 사용하여 투과증발 분리법에 대한 최근의 연구 동향에 대해서 간략하게 서술하고자 한다.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1993.06a
• /
• pp.31-56
• /
• 1993

투과증방법은 역삼투법보다 더 먼저 개발이 진행되었으나 에너지의 소비가 증류법보다 높아 상업화가 진행되지 못하다가 연료용 에탄올의 탈수공정중 공비혼합물 분리공정에서 고순도의 에탄올제조시 증류법과 혼합하여 사용되고 있다. 그러나 다른 유기물의 분리에 적용하기 위해서는 막재료의 개발이 시급히 요구되고 있다. 이 외에도 가스분리, 투석등도 상업화가 진행되고 있지만 아직은 초기단계에 머무르고 있는 실정이므로 여기에서는 막분리기술의 공정설계를 설명하기 위하여 가장 많이 보급되고 개발이 많이 진행된 역삼투막 공정을 중심으로 공정설계를 설명하고자 한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2009.05a
• /
• pp.67-70
• /
• 2009

Because many research using rocket grade peroxide is studied, distillation method for domestic production of rocket grade hydrogen peroxide is required. Distillation methods are very various and divided by feeding method, distillation time, distillation pressure, and so on. Among these, vacuum distillation is a suitable method for hydrogen peroxide. This method can reduce thermal decomposition and reaction with impurities. Distillation condition is determined by Raoult's law. Low vacuum level and vacuum level control are appeared as important problems of the experiment equipment, which are solved by using less leakage vacuum chamber and metering valve.

• Proceedings of the Membrane Society of Korea Conference
• /
• 2004.03a
• /
• pp.103-121
• /
• 2004

막분리법은, 물질을 분리하는 분리기술의 하나이다. 분리기술에는 증류법, 흡착법등의 다양한 방법이 있지만, 막분리방법은 일반적으로 분리기능을 갖는 고체의 막을 이용하는 특징을 가지고 있다. 다음의 그림에는 나타나 있는 각종 분리기술에 대해 분리에 이용하는 성질과 대상으로 하는 물질의 크기를 나타내고 있다. 표시되어 있는 공정이 분리막법의 공정이다. 막분리법은 사용한 막의 종류에 따라 분리레벨에서 입자레벨에 까지 폭넓게 적용 가능하다. (중략)

• Korean Journal of Soil Science and Fertilizer
• /
• v.33 no.5
• /
• pp.369-375
• /
• 2000

To find a quick test procedure for soil nitrate concentration, two methods, i.e. "Nitracheck 404" reflectometer (Eijkelkamp, Netherlands) with nitrate test strip and a portable colorimeter "Hanna Ion Specific meter(USA) with a color development reagent, were tested for twenty soils with different nitrate contents ranged between from $10mg\;kg^{-1}$ to $340mg\;kg^{-1}$. The standard deviation, coefficient of variability, and recovery from these quick test procedures were compared with those measured by conventional Kjeldahl distillation method and nitrate ion electrode method. The nitrate concentration measured by portable colorimeter method was higher in soils with low concentration and lower in soils with high concentration than those measured by conventional methods. However, concentrations measured by test strip reflectometer method was showed the similar coefficient of variability and recovery as those by conventional methods for all soil samples. From the experimental results in this study, the test strip reflectometer method was thought to be recommendable one revealed the satisfied results for accuracy, quickness, and simplicity for field test of soil nitrate concentration.

• Proceedings of the Membrane Society of Korea Conference
• /
• 1992.04a
• /
• pp.1-4
• /
• 1992

기존의 일반적인 에탄올 제조법으로는 1) ethylene의 가수분해, 2)전분이나 당분의 발효, 3)acetylene으로부터 얻은 acetaldehyde의 환원반응이 있다. 기존의 화석연로에 의존하지 않고 에탄올을 생성하는 방법은 발효에 의한 방법이다. 발효에 의해 생성되는 에탄올의 농도는 batch식 발효에서 13-14%, 고정화 발효방법에서 5-10%정도이다. 이를 고순도의 에탄올로 농축하기 위한 방법으로는 증류법, 투과증발법, 역삼투법등이 있으며 증류를 이용하여 농축하는 경우에는 상당히 큰 열에너지를 필요로 한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
• /
• 2009.11a
• /
• pp.89-92
• /
• 2009

Because many research using concentrated hydrogen peroxide as propellant is studied, research for distillation method for domestic production of rocket grade hydrogen peroxide is needed. To distill hydrogen peroxide, vacuum distillation will be used because of heat decomposition of hydrogen peroxide. Distillation pressure is 30 torr which is determined by Raoult's law to distill under $40^{\circ}C$. Variable of distillation experiment is distillation temperature. And the comparison of distillation results was done by yield and operation time. In the result, generally, yield was lower and the water in receiver had higher concentration with shorter distillation time. And with similar time, when distillation temperature was higher, yield was lower and hydrogen peroxide became higher concentration.

• Clean Technology
• /
• v.20 no.1
• /
• pp.13-21
• /
• 2014

Because of the water scarcity caused by the increase of salinity in the underground water, seawater desalination stands out as one of the most promising solution. As there are so much energy costs in operating desalination plants, new hybrid process which is more effective should be researched. A geothermal VMD (vacuum membrane distillation) hybrid process is a competitive alternative for seawater desalination. Because geothermal energy has significant characteristics of high capacity factor to operate the power plant at full capacity for 24 hour per day, it can be a priority heat source of VMD superior to any other renewable energies such as solar and wind power. In this study, we design a geothermal VMD hybrid process, analyze it economically and finally compare the result with a case of conventional VMD process. Geothermal VMD hybrid process generates $23,822,409 of NPV (net present value) more than the conventional VMD process in case of 5% discount rate. The break-even point between these processes is 5.36 year. Sensitivity analysis indicates that steam cost is the most decisive influence variable to the economic outcome.

• Korean Journal of Food Science and Technology
• /
• v.14 no.2
• /
• pp.174-178
• /
• 1982

Various separation methods such as solvent extraction, chemical treatment and molecular distillation were tested for the separation of tocopherols and sterols from soy oil scum. The end products of these methods were tocopherol concentrates and sterol crystals. In the solvent extraction, purity and yield of tocopherols were 21.2% and 28.3%, and those of sterols were 69.2% and 2.6%. In the chemical treatment, purity and yield of tocopherols were 11.8% and 76.4% and those of sterols were 85.1% and 34.3% respectively. In the molecular distillation, purity and yield of tocopherols were 45.0% and 68.0%, and those of sterols were 49.3% and 57.0% respectively. The end products from the methods were characterized by HPLC. Based on the results of this study, the molecular distillation method was found to be more efficient than any other method tested.