꼬막 패각의 특성과 소성 온도 영향

김윤섭 ( Youn-sop Kim ),임은옥 ( Eun-ok Lim ),서성규 ( Seong-gyu Seo ) 한국환경기술학회 2017 한국환경기술학회지 Vol.18 No.4

본 연구에서는 꼬막 패각으로 인한 환경오염문제를 해결하고 천연 탄산칼슘(CaCO₃), 산화칼슘(CaO)의 친환경적 자원화 효율을 높이기 위한 방안으로, 꼬막 패각의 특성과 소성온도의 영향을 검토하였다. 꼬막 패각의 주성분으로 Ca가 40.87%로 가장 많았으며, As, Cd, Cr, Pb, Hg 등의 유해 중금속은 불검출로 나타났다. 열적 특성은 소성온도가 600℃ 이하에서는 CaCO₃, 800℃ 이상에서는 감량화 비율을 고려할 때 완전한 CaO 형태로 존재하는 것을 알 수 있다. 고온 소성과정 중 CaCO₃가 CaO로 전환되는 과정에서 발생되는 이산화탄소(CO₂) 기포에 의해 다공성 또는 미세한 입자화가 진행되며, 소성한 시료의 비표면적 증가에 크게 기여하는 것으로 판단된다. 꼬막 패각의 결정구조는 120℃ 건조의 경우 CaCO₃(Aragonite), 소성에 따라 550℃에서는 CaCO₃(Calcite), 950℃에서는 CaO(Lime, syn) 형태였다. 소성온도에 따른 꼬막 패각의 pH 변화는 소성온도와 농도가 증가 할수록 증가하는 경향을 보였으며, 최대 pH를 얻기 위한 최적 조건은 소성온도는 850℃, 농도는 1.78 g/L로 판단된다. The characteristics of the Cockle shell and the effect of calcination temperature were investigated in this study to solve the environmental pollutions caused by Cockle shell, and to improve the eco-friendly recycling efficiencies of natural calcium carbonate (CaCO₃) and calcium oxide (CaO). Ca, as the main and minor chemical components of Cockle shell, was the highest with 40.87%, and harmful heavy metals such as As, Cd, Cr, Pb and Hg were not detected. For the thermal characteristics, CaCO₃ was dominant species below 600℃, and a complete CaO form was dominant over 800℃ with considering of the volume reduction ratio. Porous or fine granulation was progressed by carbon dioxide (CO₂) gases, which were generated during the conversion from CaCO₃ to CaO at high temperature calcination process, and the specific surface areas of the calcined sample were increased as well. The crystal structure of Cockle shell was CaCO₃ (Aragonite) at 120℃, and CaCO₃ (Calcite) at 550℃ and CaO (Lime, syn) at 950℃ depending on the calcination process. The pH of solution with Cockle shell was increased with increasing calcination temperature and concentration. The optimum calcination temperature and concentration of Cockle shell for the maximum pH were at 850℃ and 1.78 g/L, respectively.

고압에서 CO2 - 아세토니트릴과 CO2 - 아크릴로니트릴계에 대한 상거동에 관한 연구

변헌수,김윤섭,임종균 ( Hun Soo Byun,Youn Sop Kim,Jong Kyun Im ) 한국공업화학회 1998 공업화학 Vol.9 No.6

수소에 의한 In2O3 의 환원반응속도론 연구

남기석,김윤섭,이화영 ( Kee Suk Nahm,Youn Sop Kim,Wha Young Lee ) 한국공업화학회 1992 공업화학 Vol.3 No.2

수소에 의한 In_2O_3의 환원반응을 열중량분석기를 이용하여 실험적으로 연구하였다. In_2O_3의 환원 반응은 300℃ 이상에서 일어났다. 환원반응속도는 반응온도에 따라 급격히 증가하였으나, 수소의 유량에 대해선 거의 영향을 받지 않았다. 비반응핵모델을 In_2O_3의 환원반응에 적용한 결과 In_2O_3의 표면에서 수소와 In_2O_3 의 화학반응이 율속단계임을 알 수 있었다. In_2O_3의 환원반응 겉보기 활성화에너지는 20㎉/g-㏖ H_2였으며 환원반응속도식은 다음과 같이 얻어졌다. dt/dX=1.6×10^5 e^(-20000/RT).(1-X)^(2/3) The experimental study on the reduction of In_2O_3 was performed by using thermogravimetric analyser. The reduction of In_2O_3 was occurred at above 300℃ , The reduction rates were rapidly increased with the reaction temperature, while hardly affected by the flow rate of hydrogen gas. It was found that the unreacted core model could be applied for the analysis of the reduction data and the rate control step was the chemical reaction of In_2O_3 with hydrogen on the surface of unreacted In_2O_3. The apparent activation energy for this reaction was 20㎉/g-㏖ H_2 and the rate equation of In_2O_3 reduction with hydrogen could be expressed in the folowing equation. dt/dX=1.6×10^5 e^(-20000/RT).(1-X)^(2/3)

고압에서 CO₂-아세토니트릴과 CO₂-아크릴로니트릴계에 대한 상거동에 관한 연구

변헌수,김윤섭,임종균,Byun, Hun-Soo,Kim, Youn-Sop,Im, Jong-Kyun 한국공업화학회 1998 공업화학 Vol.9 No.6

본 연구에서는 고압하에서 이산화탄소와 니트릴계인 아세토니트릴 (acetonitrile)과 아크릴로니트릴 (acrylonitrile)과의 이성분계에 대한 상평형데이터를 얻기 위해 실험을 수행하였다. 실험장치는 정지형으로서 본 실험을 위해 자체 제작하여 사용하였으며, 새로이 설계된 실험장치의 재현성과 정확도를 실험하기 위해 $75^{\circ}C$에서 이산화탄소-아세토니트릴계의 실험을 수행하여 McHugh 등[1]의 실험결과와 비교하였다. 이산화탄소와 아세토니트릴과의 이성분계 상거동 실험은 온도 $55.0^{\circ}C$, $75.0^{\circ}C$, 그리고 $100.0^{\circ}C$에서 실험하였으며, 이때 압력은 2.4~14.5 MPa 범위였으며, 이산화탄소-아크릴로니트릴계의 상평형 실험은 온도 $45.0^{\circ}C$, $65.0^{\circ}C$, $85.0^{\circ}C$, 그리고 $105.5^{\circ}C$와 압력 1.6~13.9 MPa 근처까지 실험하였다. 두 계에 대해 동일한 압력에서 아세토니트릴과 아크릴로니트릴의 용해도는 온도가 증가함에 따라 증가함을 알 수 있다. 또한 두 계에 대한 혼합물 임계곡선에나타내었다. 본 연구에서 실험한 결과를 Peng-Robinson상태방정식에 의해 계산하였으며, 그 결과 실험치와 계산치와의 좋은 일치를 보였다. In this work, high pressure binary phase equilibria data of carbon dioxide with acetonitrile and acrylonitrile were obtained experimentally. A new static type experimental apparatus was built to measure temperature, pressure and phase equilibria composition. The accuracy of the experimental apparatus was tested by comparing the measured phase equilibria data of the carbon dioxide-acetonitrile system at $75^{\circ}C$ with those of McHugh and coworkers. The binary phase behavior data of carbon dioxide-acetonitirle system were measured from 2.4 to 14.5 MPa at $55^{\circ}C$, $75^{\circ}C$ and $100^{\circ}C$. Also, the phase equilibria of the system carbon dioxide-acrylonitrile were measured from 1.6 MPa up to 13.9 MPa at $45^{\circ}C$, $65^{\circ}C$, $85^{\circ}C$ and $105^{\circ}C$. The solubility of acetonitrile and acrylonitrile increases as the temperatures increases at constant pressure. Also, these two carbon dioxide-polar solute system have continuous critical-mixture curves that exhibit maximums in pressure at temperatures between the critical temperatures of carbon dioxide and acetonitrile or acrylonitrile. The experimental data obtained in this study were modeled using the Peng-Robinson equation of state. Good agreement between calculated and experimental results was observed.

수소에 의한 In₂O₃의 환원반응속도론 연구

남기석,김윤섭,이화영,Nahm, Kee-Suk,Kim, Youn-Sop,Lee, Wha-Young 한국공업화학회 1992 공업화학 Vol.3 No.2

수소에 의한 $In_2O_3$의 환원반응을 열중량분석기를 이용하여 실험적으로 연구하였다. $In_2O_3$의 환원반응은 $300^{\circ}C$ 이상에서 일어났다. 환원반응속도는 반응온도에 따라 급격히 증가하였으나, 수소의 유량에 대해선 거의 영향을 받지 않았다. 비반응핵모델을 $In_2O_3$의 환원반응에 적용한 결과 $In_2O_3$의 표면에서 수소와 $In_2O_3$의 화학반응이 율속단계임을 알 수 있었다. $In_2O_3$의 환원반응 겉보기 활성화에너지는 20kcal/g-mol $H_2$였으며 환원반응속도식은 다음과 같이 얻어졌다. ${\frac{dX}{dt}}=1.6{\times}10^5e^{-20000/RT}(1-X)^{2/3}$ The experimental study on the reduction of $In_2O_3$ was performed by using thermogravimetric analyzer. The reduction of $In_2O_3$ was occurred at above $300^{\circ}C$. The reduction rates were rapidly increased with the reaction temperature, whilehardly affectedby the flow rate of hydrogen gas. It was found that the unreacted core model could be applied for the analysis of the reduction data and the rate control step was the chemical reaction of $In_2O_3$ with hydrogen on the surface of unreacted $In_2O_3$. The apparent activation energy for this reaction was 20kcal/g-mol $H_2$ and the rate equation of $In_2O_3$ reduction with hydrogen could be expressed in the following equation. ${\frac{dX}{dt}}=1.6{\times}10^5e^{-20000/RT}(1-X)^{2/3}$

Hexamethoxymethylmelamine 이 고무 - 황동피복코드간의 접착에 미치는 영향

김완영,김윤섭,육경창,김형순,이정용,최상원 ( Wan Young Kim,Youn Sop Kim,Gyeong Chang Yug,Hyung Soon Kim,Jeong Yong Lee,Sang Won Choi ) 한국공업화학회 1992 공업화학 Vol.3 No.3

본 연구는 고무와 황동피복 코드간의 접착력 향상을 위하여 사용되는 resorcinol formaldehyde(RF) resin과 hexamethoxymethylmelamine(HMMM)이 고무 컴파운드내에서 나타내는 morphology와 접착특성에 대하여 고찰하였다. 가황후 resin은 구형의 형태로 시편 전체에 고르게 분포되어 있었고 그의 입경은 약 2000Å정도였다. 코드와 함께 가황시킨 시편에서 코드 주위에 존재하는 resin함락이 감소한 것으로 보아 resin이 코드쪽으로 이동이 있었던 것으로 생각된다. 또한 모듈러스는 methylene donor인 HMMM의 양이 많을수록 증가하였으며, 접착층이 더 두껍게 형성되었다. 접착력은 열노화에 의하여 상실되며 이는 대부분 초기에 발생함을 알 수 있었다. 접착컴파운드에서 가장 유리한 RF resin과 HMMM의 비는 물성, 접착층의 안정성, 열노화특성 등을 고려할 때 1 : 0.9이었다. The morphology and adhesion properties of rubber compounds containing resorcinol formaldehyde(RF) resin and hexamethoxymethylmelamine (HMMM) used in adhesion of rubber to brass-plated steel cord was investigated. The resins were spherical particles about 2000Å diameter and distributed in rubber compounds homogeneously, and the cured compound with steel cord showed migration of resin to steel cord. Also, modulus was increased with increasing HMMM contents. The loss of adhesion between rubber and steel cord was likely to be at initial stages by thermal aging. Considering the physical properties, stability of adhesion layer and thermal aging property, optimum ratio of RF resin and HMMM was 1 : 0.9.

지황 추출물 첨가 chitosan 기반 기능성 바이오 소재 제조 및 응용

이시연,김경중,김윤섭,윤순도,Lee, Si-Yeon,Kim, Kyeong-Jung,Kim, Youn-Sop,Yoon, Soon-Do 한국공업화학회 2022 공업화학 Vol.33 No.2

The main objective of this work is to prepare Rehmannia glutinosa extract (RE) incorporated functional chitosan (CH) based biomaterials and evaluate their physical properties, RE release properties, inhibitory effect of melanogenesis, and antioxidant and elastase inhibitory activities. RE incorporated CH based biomaterials were synthesized by a casting method and UV curing process. The surface and cross sections of prepared biomaterials were characterized by a field emission scanning electron microscope (FE-SEM). The physical properties such as tensile strength and elongation at break were also investigated. To apply the transdermal drug delivery system, RE release properties were examined with pH 4.5, 5.5, and 6.5 buffer solutions and artificial skin test at 36.5 ℃. Results indicated that RE release of RE incorporated biomaterials with/without the addition of plasticizers [glycerol (GL) and citric acid (CA)] at pH 6.5 was about 1.10 times higher than that of at pH 4.5. In addition, results of the artificial skin test verified that RE was released constantly for 6 h. To verify the applicability of the prepared biomaterials, tyrosinase, 2,2-diphenyl-1-picrylhydrazyl (DPPH), and elastase assays were investigated. Results indicated that RE incorporated biomaterials added CA exhibited tyrosinase activation, DPPH radical scavenging activity rate, and elastase activation of 45.12, 89.40, and 59.94%, respectively.

황 및 가황 촉진제의 함량에 따른 NR / BR 블렌드의 가황과 물리적 , 기계적 특성의 변화

김완영,이대수,김윤섭,김형순,라창운 ( Wan Young Kim,Dai Soo Lee,Youn Sop Kim,Hyung Soon Kim,Chang Woon Nah ) 한국공업화학회 1991 공업화학 Vol.2 No.4

가황계에 따른 NR/BR 블렌드의 물리적 · 기계적 특성의 변화를 가교밀도의 차이로 해석하였다. 경화제의 비율 및 함량이 증가함에 따라 가황속도 및 최대 토오크는 증가를 보였으며, 가교밀도도 증가하였다. 가교밀도의 증가에 따라 경도, 300% 모듈러스, 반발탄성 및 마모특성은 증가를 보인 반면에 발열에 의한 온도 상승 및 60 ℃ 에서의 tan δ는 감소를 보였다. 따라서 높은 하중이 가해지는 트럭/버스 타이어의 트레드 부위에 사용하는 경우 회전저항이 적은 semi-EV 가황계가 가장 적절한 가황 시스템으로 판단되었다. The physico-mechanical properties of NR/BR blend were measured, and the results were interpreted in terms of the crosslink density with cure system. The cure rate, maximum torque and crosslink density increase with the content and ratio of curative for cure system. Hardness, 300% tensile modulus, rebound and wear resistance increase with crosslink density of the vulcanizate but heat build-up and tan δat 60 ℃ decrease. It is expected that semi-EV(efficient vulcanization) cure system is appropriate for application in tire tread of truck/bus in which load bearing property is impotant.

고무 種類에 따른 고무 컴파운드의 加黃과 物理的·機械的 特性

金潤燮 麗水水産大學校 産業技術硏究所 1993 産業基術硏究所 論文集 Vol.2 No.-

Vulcanization and physico-mechanical properties of rubber compound with type of rubber containing carbon black were investigated experimentally. In case of various rubber compounds, cure rate was most fast in the NR having methyl functional group in polymer chain. The decreases of glass transition temperature(Tg) of rubbers resulted in increases of rebound property and wear resistance, and heat buildup and tan δ(60℃) of the NR, solution polymerized-styrene butadiene rubber-I(S-SBR-I, bound Styrene : 18%, vinyl content :10%) and BR compound were relatively lower than others. Especially, it was expected that NR and S-SBR-I, from the view points of physico-mechanical properties and hysteresis of rubber compound for the tread compound in truck/bus tires in which loading bearing property is important.

인계 난연제를 사용한 PC/ABS/SAN 수지의 특성

김윤섭,이종근 여수대학교 2001 論文集 Vol.16 No.-

Characteristics of polycarbonate(PC)/poly(acrylonitrile-butadiene-styrene, ABS)/poly(styrene-acrylonitrile, SAN) composites were investigated by using non-halogenated fire-retardant such as triphenyl phosphate (TPP). The fire retardancy and impact strength of composite systems were thoroughly examined by using UL-94 V method and Izod impact tester. Comparing the reference samle(R) fire resistance of phenol/TPP/hexamine(NHMB) systems showed the same as V-0 grade in PC/ABS/SAN composites when NHMB 40phr was added, and heat distortion temperature(HDT) was about 81℃. Impact strength and HDT increased with an increase of the NHMB content but melt index(MI) decreased.