초음파가 조사된 고압반응기에서 분획된 Polystyrene 의 분자량 분포특성

홍인권,김형진,이승범 한국고무학회 1997 엘라스토머 및 콤포지트 Vol.32 No.3

In this study, the ultrasonic irradiation in elevated pressure was used to alter the molecular weight and MWD of polystyrene. The high pressure reactor was filled with 0.5w/v% polystyrene solution, and then it was pressurized from 500psi to 4000psi. The ultrasound was irradiated in 10 minutes at each pressure, and the extract was collected and analyzed by GPC. Molecular weight distribution was predicted by log-normal and Schulz distribution function. The average molecular weight and polydispersity of polystyrene were decreased, as the pressure applied during the ultrasonic irradiation was increase. It was able to fractionate polymer material and control polydispersity by adjusting pressure in the ultrasonic irradiation.

열분해를 이용한 범용고무의 환경친화적 처리공정 해석

홍인권,김원일,이승범 한국고무학회 2000 엘라스토머 및 콤포지트 Vol.35 No.4

The experimental kinetics was analyzed for commercial rubbers such as NR, IR, BR, SBR 1500, and SBR 1700. Kinetic analysis for the commercial rubbers was performed using a thermogravimetric method, which the activation energies of NR obtained by Kissinger, Friedman, and Ozawa's method were 195.0, 198.3, and 186.3 kJ/㏖, respectively, whereas that of SBR 1500 were 246.4, 247.5, and 254.8 kJ/㏖, respectively. It was shown that the yield of pyrolytic oil was generally increased with increasing the final temperature. Considering the effect of heating rate, it was found that the yield of pyrolytic oil was not consistent for each sample. The number average molecular weight of pyrolitic oil of SBR 1500 was in the range of 740-2486. The calorific value of SBR 1500 was 39-40 kJ/g, and it might be a considerable energy potential although it was lower than the conventional fuel such as kerosene, diesel, light fuel, and heavy fuel.

압력이 가해진 반응공정에서 BTX의 촉매산화 전환특성

홍인권,이승범 단국대학교 2000 論文集 Vol.35 No.-

Catalytic oxidation of benzene, toluene, and m-xylene (BTX) was carried out in high pressure tubular reactor packed with 0.5% Pt/γ-Al_2O_3 catalyst. The conversions of BTX were increased as the inlet concentration was decreased and the reaction temperature and the molar density of oxygen were increased. And the molar density of oxygen was increased with pressure. The maximum deep conversion of benzene, toluene and m-xylene were 92.1%, 66.0% and 57.5% at 350℃ and 136 atm, respectively. In this study, the many intermediates produced by the partial oxidation of BTX was detected from off-line samples.

기능성 고분자 막의 기체 투과 특성

홍인권,이승범,김원일 단국대학교 1998 論文集 Vol.32 No.-

The permeation of gases through polymer membranes at temperatures above their glass transition, generally occurs by a solution-diffusion mechanism. This mechanism obeys to affinity difference between polymeric materials and gas molecules, various technologies, such as copolymerization, impregnation and so on, have been researched to improve the affinity of polymeric material for the gases. In this study, permeability and selectivity for some gases were obtained from steady-state rates of gas permeation through silicone rubber membrane which is prepared by supercritical fluid extraction method. The permeation rates were measured by means of a permeability apparatus of the variable volume type. The permeability was increased generally with permeation temperature and pressure. Silicone rubber membrane exhibits a higher permeability to CO_2 than to O_2, N_2. This result probably reflects the relatively high solubility of CO_2 in silicone rubber membrane, which is due to the affinity of the CO_2 molecules to the silicone rubber membrane. Since the separation power of CO_2/N_2, CO_2/O_2 was more than 200, and 100, it is able to separate CO_2 from the air, and the optimum temperature and pressure was 55℃, 60㎝Hg respectively. In future, it is possible that the silicone rubber membrane can be used for separation or concentration of CO_2 through experiment for mixed gas separation.

원료탄의 배합비율에 의한 활성탄의 기능성 향상

홍인권,김상철,김원일,이승범 단국대학교 1998 論文集 Vol.33 No.-

Adsorption characteristics of activated carbon were affected by raw materials and operating conditions. Coal based activated carbons were prepared in a rotary kiln type furnace and the pretreatment effect of raw materials for preparing activated carbon was investigated. Steam was employed in manufacturing process as an activation agent. Activation temperature affected the properties of activated carbon. The adsorption capacity, or iodine value was increased in te activation temperature range of 800 to 900℃, yet decreased at higher temperatures than 900℃. Then, the activation effect was analyzed in terms of the activated carbon(AC) yield. It was found that the optimum heating rate and steam amount were 2.9℃/min, and 1g steam/g coalㆍhr, respectively. Effect of coal blends on the preparation of activated carbon was examined. The developing patterns of pore structure were varied with mixing ratio. As the amount of anthracite coal was increased, AC yield increased but adsorption capacity decreased. Pore size and pore size distribution were examined by BET specific surface area analyzer. In the AC yield range of 30∼40%, prepared activated carbon has micropores of sizes below 30Å and iodine value was above 1,000㎡/g in the temperature range of 850∼900℃. Benzene adsorption capacity was similar to those of mixed and Fushun coal but MEK adsorption capacity was superior to that of functions mixed coal. We found that the activated carbon based on coal has comparable to those of commericial products.

통계열역학 (교재 소개)

홍인권 한국공업화학회 2008 공업화학전망 Vol.11 No.2

기상으로 존재하는 유독성유기용매의 완전산화 메커니즘

홍인권,이승범 단국대학교 1999 산업기술연구 Vol.1 No.-

The deep oxidation mechanism of gaseous toxic organic solvents was studied on a Pt / γ-Al_2O_3 catalyst phase at temperature ranging from 200 to 350℃. An approach based on the Mars-van Krevelen rate model was used to correlate the results. The objective of this study was to depict the kinetic behavior of the platinum catalyst for deep oxidation of VOCs. The conversions of VOCs were increased as the inlet concentration was decreased and the reaction temperature was increased. The maximum deep conversion of MEK, benzene and toluene were 91.81%, 75.45% and 55.69% at 350℃, respectively. The k_3 constant increases with temperature faster than K_1 the constant, that is, the surface concentration of (VOCs…O) is higher than that of (O) at higher temperature according to the Mars-van Krevelen mechanism. Also, the oxidation activation energy of toluene was larger than MEK for toluene is aromatic compound which have stronger bonding energy. Therefore, the catalytic oxidation mechanism of VOCs with Mars-van Krevelen could be used as the basic data for industrial oxidation processes.

Polystyrene Latex 제조공정에서 초음파 에너지의 개시효과

홍인권,김원일,이승범 한국고무학회 1996 엘라스토머 및 콤포지트 Vol.31 No.3

Polymer latices, prepared from the emulsion polymerization of vinyl monomer compounds, are widely used for many industrial applications. Included among these are uses in paints, adhesives, flocculants, and heavy-duty plastics as well as their original use in synthetic rubber compounds. The emulsion polymerization process with chemical initiator has chemical disadvantage such as removal of initiator which was left after polymerization. In this study, polystyrene latex was prepared by using ultrasonic irradiation which generate the free radical, and then it was analyzed by GPC. Reaction temperature hardly have an effect on average molecular weight. Average molecular weight is increased by increasing amount of surfactant, i.e. SDS, but polydispersity is decreased. After 90 minutes of reaction time, increase and decrease of average molecular weight is repeated. It is proposed that monodisperse polymer is obtained by controlling ultrasonic irradiation time and surfactant concentration.

초음파를 활성화 에너지로 하는 Polystyrene Latex의 중합 특성

홍인권 檀國大學校 出版部 1999 論文集 Vol.34 No.3

Pulse 형태로 조사된 초음파 활성화에너지에 의한 Polystyrene 라텍스 중합 특성

홍인권,윤용수,김형진,이승범,김원일 한국공업화학회 1997 응용화학 Vol.1 No.2

There are many methods to syntesize polystyrene latex. Emulsion polymerization is often used commercially, but initiator has the disadvantage for environmental pollution. The free radical is produced by ultrasound energy effect, polystyrene latex was synthesized using ultrasound energy instead of chemical initiator. As the ultrasonic irradiation time increased, average molecular weight increased and polydispersity decreased. And as the concentration of SDS increased, degree of polymerization increased and maximum value of degree of polymerization was shown when the concentration of SDS was 2 wt%, and reaction temperature was 40℃. During the polymerization, increase and decrease of molecular weight was repeated and molecular weight controlled monodisperse type polystyrene latex was synthesized by controlling of ultrasonic irradiation time and the concentration of SDS.