• 한국환경과학회지
• /
• 제13권4호
• /
• pp.403-412
• /
• 2004

Waste water-soluble cutting oil was treated with WI type #1 and WI type #2. The properties of the original water-soluble cutting oil were pH=l0.4, viscosity=1.4cP, CODcr=44,750 ppm, and TOC=10,569 ppm. However, the properties of the oil used for more than 3 months were changed to pH=7.82, viscosity=2.1cP, CODcr=151,000 ppm, and TOC=74,556 ppm. It might be attributed to the fact that molecular chains were cut due to thermal oxidation and impurities such as metal chips were incorporated in to the oil during the operation processes. To prevent the putrefaction of oil, the sterilization effect of ozone and UV on the microorganism in the oil was investigated. Ozone treatment showed that 99.99% of the microorganism was annihilated with 30 minutes contact time and 60 minutes were necessary for the same effect when UV was used. Ozone treatment could cut molecular chains of the oil due to strong sterilization power, which was evidenced by the increase of TOC from 25,132 ppm at instantaneous contact to 28,888 ppm at 30 minutes contact time. However, UV treatment didn't show severe changes in TOC values and thus, seemed to cause of severe cut of molecular chains. When the activated carbon was used to treat the waste water-soluble cutting oil, TOC decreased to 25,417 ppm with 0.lg carbon and to 15,946 ppm with 5.0g carbon. This results indicated that the waste oil of small molecular chains could be eliminated by adsorption. From the results, it could be concluded that these treatment techniques could be proposed to remove the waste oil of small molecular chains resulting in the degradation of the oil properties. In addition, these experimental results could be used for the correlation with future works such as investigation of the molecular distribution according to the sizes, lengths, and molecular weight of the chains.

• 한국식품과학회지
• /
• 제17권2호
• /
• pp.75-80
• /
• 1985

Lipase를 유지분해에 이용하기 위한 기초연구로서 Candida cylindracea에서 추출된 lipase를 흡착법에 의해 고정화하고 그의 반응특이성을 본 결과는 다음과 같다. Lipase 흡착에 적합한 흡착제로는 silica gel이 선정되었으며, Silica gel 1.6g에 lipase 47.5 units를 $5^{\circ}C$, PH 7.0에서 100분간 흡착시키는 것이 좋았다. Silica gel에 고정화 시킨 lipase를 유지방과 olive oil의 분해에 적합한 최적온도 및 최적pH는 가용성효소와 비교시 $37^{\circ}C$, pH 7.0으로 변하지는 않았으나 활성의 범위는 넓어졌다. 또한 열안정성 및 pH안정성도 가용성 효소에 비하여 활성의 범위가 넓어졌다. 유지의 분해에 적합한 고정화 효소의 최적효소농도는 유지방의 경우 30g이었으며 올리브유의 경우 80g으로 선정하였다. 이 때 최적기질농도는 유지방 및 올리브유 모두 20%였다. 반응시간에 따른 반응률은 유지방을 이용하여 조사한 결과 가용성 효소는 반응 4시간까지는 급격한 분해를 나타냈으나 고정화 효소는 8시간 까지 급격한 증가를 나타내고 그 이상은 거의 일정하였다. 또한 유리되는 지방산의 profile은 가용성 효소와 비교시 capric acid의 생성은 모두 높았으며, myristic acid의 함량은 높고 butyic acid의 함량은 적었다.

• Advances in environmental research
• /
• 제4권2호
• /
• pp.69-81
• /
• 2015

A new magnetite-silica core/shell nanocomposite ($Fe_3O4@nSiO_2@mSiO_2$) was synthesized and functionalized with trimethylchlorosilane (TMCS). The prepared nanocomposite was used for the removal of diesel oil from aqueous media. The characterization of magnetite-silica nanocomposite was studied by X-ray diffraction (XRD), Fourier transform infrared (FTIR), transmission electron microscopy (TEM), surface area measurement, and vibrating sample magnetization (VSM). Results have shown that the desired structure was obtained and surface modification was successfully carried out. FTIR analysis has confirmed the presence of TMCS on the surface of magnetite silica nanocomposites. The low- angle XRD pattern of nanocomposites indicated the mesoscopic structure of silica shell. Furthermore, TEM results have shown the core/shell structure with porous silica shell. Adsorption kinetic studies indicated that the nanocomposite was able to remove 80% of the oil contaminant during 2 h and fit well with the pseudo-second order model. Equilibrium studies at room temperature showed that the experimental data fitted well with Freundlich isotherm. The magnetic property of nanocomposite facilitated the separation of solid phase from aqueous solution.

• Korean Chemical Engineering Research
• /
• 제48권4호
• /
• pp.444-449
• /
• 2010

본 연구에서는 정유회사 등에서 폐기되는 부생유(pyolyzed fuel oil)를 황산화 반응하여 petroleum sulfonate(PS)를 합성하였다. 합성된 PS는 계면활성 성질을 나타내었으며 이는 황산화율과 관계가 있었다. 또한 반응에 있어서 황산화율은 온도 및 시간에 따라 속도에 차이는 있었으나 대부분의 경우 40~50% 정도에서 황산화율이 거의 포화에 이르렀다. 황산화율이 증가함에 따라서 친수성이 증가하여 용액의 표면장력이 낮아졌으나 과도한 황산화율에서는 친수성이 너무 강하여 표면장력 값이 오히려 증가하였다. 황산화율에 따라서 적정한 친수-친유 비율에서는 낮은 표면장력과 시멘트에 대하여 우수한 젖음성을 나타내었다. 황산화율에 따라서 PS는 시멘트 표면에 대한 흡착량에 차이를 보였으며 흡착량이 클수록 시멘트에 대한 젖음성이 증가하여 시멘트 입자의 제타전위를 높였으며 보다 우수한 시멘트 몰타르 유동성을 나타내었다.

• 해양환경안전학회지
• /
• 제7권1호
• /
• pp.7-14
• /
• 2001

The amount of petroleum consumption has been Increased according to the industrialization and It leads to the increase of the possibility of marine oil pollution. In Korea, some countermeasures including oil skimmer, gelling agent and herding agent of oil have been used for the remediation of the pollution. However, most of them have lets of shortcomings in the application under in-situ condition, because they are sensitive to the situation such as geographical feature, the wind and the tide. In reported literature, the natural powdered oil absorbent which is made of peat moss is an effective mean to clean spilled oil from lake or coast. However, the peat moss is a natural resource which is only Produced from a specific cold weather are like Canada. This indicates that the alternative materials which is readily obtained from everywhere are needed for powdered oil absorbent. Therefore. in the study, same natural materials including pine leaves and straw are tested as the alternative materials for the absorbent. The raw materials were dried and treated by heat at various temperature during several Periods and then. shattered by a grain cracking machine. The oil sorption capacity of the prepared materials was compared according to the methods of heat treatment and their sizes. The proportion of hydrogen cyanide to combustion of the absorbents was measured to confirm their final disposal methods. The biodegradability test of the absorbents was carried our to evaluate possibility of a side pollution in the coast. In was found that the heat treatment of pine leaves enhanced the capacity of oil sorption and decreased the water sorption. The maximum oil sorption was observed for the material treated at 18$0^{\circ}C$for 60 min. The amount of hydrogen cyanide from the combustion were 0.09ml/g, 0.07ml/g for pine leaves and straw respectively meaning that the final disposal by combustion might be feasible. The amount or organic carbon extracted from pine leaves during 7 days was up to 0.015g organic carbon from one gram of pine leaves. but the degradation was as fast as for glucose. It is concluded that the pine leaves can be served as a good raw material for the powdered oil absorbent like peat moss.

• KSBB Journal
• /
• 제10권5호
• /
• pp.582-588
• /
• 1995

해양의 유류유출이 잦은 지역으로부터 crude oil 분해능이 뛰어난 미생물을 분리하여 통정한 결과 Pseudomoans 속으로 판명되였으며, 이를 Pseud$\sigma$ moans sp. CHCS-2로 명 명하였다. 이 균주가 배양 중에 생산하는 biosurf actant의 생생 최적 pH 및 NaCI 농도는 각각 8.0 및 3.0% 였으며, 질소원인 peptone에 영향을 받았다. 2% Kuwait crude oil이 첨가된 배양액을 48, 96, 132시간별로 gas chroma­t tography를 이용, 잔류 oil을 분석한 결과 Kuwait crude oil의 C10-CI4부위에 biosurf actant가 작용하여 분해하였으며, 배양 상층액으로부터 Amberlite XAD-7을 이용한 흡착 chromatography와 Sepha­d dex G-100을 이용한 gel chromatography, 그리고 HPLC를 이용하여 biosurf actant를 분리. 정제한 결과 유화력이 뛰어난 단일 peak를 얻었다. Bio-sur­f f actant 유화력은 $40^{\circ}C$에서 가장 좋았으며, 안정성 은 $30^{\circ}C$에서 $60^{\circ}C$까지의 넓은 온도 범위에서 유지 되었다. 또한, 정제된 biosurf actant를 이용하여 계 연장력에 미치는 영향을 검토한 결과, 상엽적으로 널리 판매되고 있는 Tween 80, Tween 60 그리고 SDS보다 표연장력 저하능력이 뛰어난 것으로 밝혀졌다.

• 한국식품과학회지
• /
• 제18권6호
• /
• pp.468-474
• /
• 1986

대두단백질의 용해도, 소수성, 에멀젼의 유동특성, 물-기름 계면에서의 단백질 흡착 및 계면장력과 유화 특성과의 관계를 연구 검토 하였다. 등전점 부근에서 단백질의 유화능력과 유화안정도가 최소였으며, 단백질 용액의 pH가 이로부터 산성과 알칼리성 쪽으로 갈수록 유화특성이 증가하는 경향으로, 대두단백질의 용해도와 비슷한 경향을 보였다. 에멀젼의 온도가 증가함에 따라 $50^{\circ}C$까지는 유화형성능력이 증가하다가 그 이상에서는 약간 감소하였으며, 유화안 정도는 온도 증가에 따라 계속 감소하는 경향을 보였다. 인산염이 존재할 경우를 제외하고는 전반적으로 염은 유화특성을 감소시켰다. 단백질의 소수성은 온도가 증가함에 따라 증가하였으며, pH가 낮아질수록 약간 증가하는 경향을 보이다가 등전정 이하 산성영역에서 급격히 증가하였다. 기름-물 계면에서 단백질의 최대 흡착량은 pH2.0에서 $0.78mg/m^2$로 가장 높았으며. 다음 pH7이었고, 등전점인 pH4에서 가장 낮았다. 대두단백질이 존재하지 않을때 물-기름 계면장력은 19.76dyne/cm 이었으나 단백질이 존재할 경우 각 조건에 따라 다소 차이는 있으나 11.45-18.08dyne/cm로 전반적으로 저하되었다.

• 공업화학
• /
• 제32권1호
• /
• pp.61-67
• /
• 2021

본 연구에서는 천연 오일인 시벅턴 오일의 천연 자외선 흡수제로의 사용 가능성을 알아보기 위하여 시벅턴 원유에 대한 흡착 탈색공정을 수행하고, 이를 CCD-RSM (central composite design model-response surface methodology)을 이용하여 최적화하였다. CCD-RSM의 반응치로는 탈색과정의 탈색효과, 탈색 후 정제유의 산가 및 290 nm에서의 자외선흡광도로 설정하였으며, 독립변수로는 탈색제의 첨가량, 탈색온도, 탈색시간으로 설정하였다. CCD-RSM에 의한 통계학적 최적화 결과와 수학적 최적화 결과를 비교한 결과 3가지 반응치를 동시에 만족하는 최적조건으로 탈색제의 첨가량(4.32 wt.%), 탈색온도(134.9 ℃) 및 탈색시간(19.8 min)으로 나타났다. 이 최적 조건하에서 예측된 반응치 중 탈색과정의 탈색효과는 94.78%, 탈색 후 정제유의 산가는 2.08 mg/g KOH, 그리고 290 nm에서의 자외선 흡광도는 2.91로 나타났으며, 오차율은 2% 이하로 낮게 나타났다. 따라서 CCD-RSM을 시벅턴 원유의 흡착 탈색공정에 적용할 경우 매우 높은 수준의 만족하는 결과를 얻을 수 있음을 확인하였으며 천연 식물성 오일인 시벅턴 오일을 천연 자외선 흡수제로서 사용 가능함을 확인하였다.

• Food Science and Biotechnology
• /
• 제17권2호
• /
• pp.324-329
• /
• 2008

The effect of ultra-high pressure homogenization on the emulsifying properties of whey protein was investigated in a model emulsion made with whey protein isolate and soya oil under various pH. The emulsifying properties, the average diameter of the oil droplets ($d_{vs}$), and the protein load, were measured for each emulsion produced at different homogenization pressures (50 to 200 MPa) and pH values (4.6 to 8.0). According to the results of variance analysis and response surface, the pH had more influence on oil droplet size and protein load than homogenization pressure. The model equations, which were obtained by response surface analysis, show that pH and homogenization pressure had the major effect on oil droplet size and protein load. Higher homogenization pressure decreased the average droplet size and the protein load. Homogenization at high pressure, as opposed to low pressure, causes no overprocessing, but the effect was pH-dependent. The average diameter of the oil droplets increased slightly by decreasing the pH from 8.0 to 6.5 and then increased dramatically toward the isoelectric point of whey protein (i.e., at pH 4.6). Moreover associated droplets were found at acidic pH and their size was increased at high temperature.

• Bulletin of the Korean Chemical Society
• /
• 제34권10호
• /
• pp.3059-3064
• /
• 2013

In this study transesterification of Triglycerides (TG) from Jatropha curcas oil (JCO) with methanol for production of biodiesel was investigated over cerium impregnated ZSM-5 catalysts. NaZSM-5 was synthesized in an alkaline medium and impregnated with cerium oxide by wet method using cerium nitrate as a source for cerium. They were characterized by X-ray diffraction (XRD), Thermogravimeteric analysis (TGA), $CO_2$-temperature programmed desorption, and $N_2$ adsorption/desorption analysis. XRD analysis showed decrease in intensity of the patterns with the increase in the ceria loading but crystallization of ceria to larger size is an evident for 10 and 15% loading. The optimal yield of transesterification process was found to be 90% under the following conditions: oil to methanol molar ratio: 1:12; temperature: $60^{\circ}C$; time: 1 h; catalyst: 5 wt %. Here the yield of fatty acid methyl ester (FAME) was calculated through $^1H$ NMR analysis. The investigation on catalyst loading, temperature, time and reusability illustrated that these ceria impregnated NaZSM-5's were found to be selective, recyclable and could yield biodiesel at low temperature with low methanol to oil ratio due to the presence of both Lewis and Bronsted basicity. Hence, from the above study it is concluded that ceria impregnated ZSM-5 could be recognized as a potential catalysts for biodiesel production in industrial processes.