Synthesis of dimethyl carbonate from transesterification of ethylene carbonate with methanol using immobilized ionic liquid on commercial silica

박대원,Kyung-Hoon Kim,Dong-Woo Kim,Cheol-Woong Kim,Jae-Cheon Koh 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.5

Ionic liquid immobilized on commercial silica catalysts proved to be an effective heterogeneous catalyst for the synthesis of dimethyl carbonate (DMC) from transesterification of ethylene carbonate (EC) with methanol. The immobilized 1-n-alkyl imidazolium halide ionic liquid on commercial silica (RImX-CS) was characterized by EA,BET, FT-IR, 13C NMR and 29Si NMR. It was found that RImX-CS with a longer alkyl chain length showed much better catalytic activity. RImX-CS with chloride (Cl−) as the counter anion showed the best catalytic activity. High temperature,high carbon dioxide pressure, and longer reaction time were favorable for the reactivity of BuImBr-CS. The catalyst can be reused for the reaction up to three consecutive runs without any considerable loss of its initial activity.

Catalytic performance of pyridinium salt ionic liquid in the synthesis of cyclic carbonate from carbon dioxide and butyl glycidyl ether

박대원,Hye-Young Ju,Ji-Yeon Ahn,Mamparambath-Dharman Manju,Kyung-Hoon Kim 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.3

The catalytic performance of pyridinium salt ionic liquids in the reaction of butyl glycidyl ether and carbon dioxide was investigated in this study. The catalytic activity was studied in a batch reactor with different 1-alkylpyridinium salt ionic liquids at 60-140 oC. The conversion of butyl glycidyl ether was affected by the structure of the ionic liquid; the one with the cation of bulkier alkyl chain length showed better reactivity. The effect of carbon dioxide pressure, reaction temperature and zinc bromide co-catalyst on this reaction was also discussed.

아크롤레인 선택 산화반응에서 Mo-V-O와 SnO₂의 상간협동 - II. 담지촉매 -

박대원,나석은,김경훈,이원호,정종식,Park, Dae-Won,Na, Suk-Eun,Kim, Kyung-Hoon,Lee, Won-Ho,Chung, Jong Shik 한국공업화학회 1994 공업화학 Vol.5 No.2

$Mo-V-O/SnO_2$(VM/Sn) and $SnO_2/Mo-V-O$(Sn/VM) catalysts have been prepared and characterized by XRD, BET, SEM and TPD of ammonia. The catalytic reaction of acrolein oxidation with these catalysts, in a continuous-flow fixed-bed reactor, showed that they had higher conversion of acrolein and higher yield of acrylic acid than those of Mo-V-O itself. The origin of the observed synergy studied by TPD, TPR and TPO is explained by the cooperation of $SnO_2$ and Mo-V-O at their interfaces where electrons flow from Mo-V-O phase to $SnO_2$ and $SnO_2$ produces spill-over oxygens, which, by being transported onto the surface of Mo-V-O, reoxidize the partially reduced active sites. 담지촉매인 $Mo-V-O/SnO_2$(VM/Sn)와 $SnO_2/Mo-V-O$(Sn/VM) 촉매를 제조하여 XRD, BET, SEM, $NH_3$, TPD 등으로 특성분석을 실시하였다. 고정층 연속 반응기에서 아크롤레인의 산화반응을 수행한 결과 이들 촉매의 아크롤레인 전화율과 아크릴산 수율이 Mo-V-O 자체보다 높았다. 이와 같은 상승효과의 원인을 TPD, TPR, TPO 등의 방법으로 고찰한 결과 Mo-V-O와 $SnO_2$의 접촉면에서 Mo-V-O가 $SnO_2$ 상으로 전자를 전달하고 $SnO_2$는 spill-over oxygen을 Mo-V-O 상으로 전달함으로써 반응에 의하여 부분환원된 Mo-V-O의 재산화를 촉진시키는 상간협동 현상이 존재하기 때문으로 판단되었다.

프로필렌 선택산화반응에서 α- Bi2Mo3O12 와 SnO2 의 상간협동 Ⅰ . 기계적 혼합촉매

박대원,김경훈,김종화,나석은 ( Dae Won Park,Kyung Hoon Kim,Jong Hwa Kim,Suk Eun Na ) 한국공업화학회 1995 공업화학 Vol.6 No.4

본 연구는 프로필렌의 선택산화반응에서 α-Bi₂Mo₃O_(12)(BM)와 SnO₂의 기계적 혼합촉매의 상승효과에 관한 메카니즘을 규명하기 위한 것이다. 촉매의 물리적 성질 및 구조를 관찰하기 위하여 BET, XRD, SEM 등을 사용하였고, 촉매의 산화-환원 특성은 승온탈착(TPD), 승온환원(TPR), 승온재산화(TPROX) 실험으로 조사하였다. BM과 SnO₂의 기계적 혼합촉매의 프로필렌 전화율과 아크롤레인 및 아크릴산의 수율이 각각의 BM과 SnO₂의 산술 평균값보다 높았다. 이와 같은 상승효과는 두 상간의 협동에 의한 것으로 추측된다. 즉 SnO₂의 산소 빈자리에 흡수된 산소이온이 경계면을 통하여 BM 상에 전달되어 이의 재산화를 촉진시키기 때문으로 판단된다. The present study was aimed to elucidate the mechanism of synergistic effect in the mechanically mixed catalysts of α-Bi₂Mo₃O_(12)(BM) and SnO₂ for the selective oxidation of propylene. Physical and structural properties of catalysts were characterized by BET, XRD and SEM. Reduction and oxidation behaviors of catalysts were studied using TPD, TPR and TPROX. Reaction test showed that the catalyst mixture had higher conversion of propylene and higher yield of acrolein and acrylic acid than either of the each metal oxide. The origin of the synergy is attributed to the cooperaton of the two metal oxide catalysts. Oxygen ions formed at the oxygen vacancies of SnO₂ move to BM and promote its reoxidation.

Synthesis of cyclic carbonate from allyl glycidyl ether and CO2 over silica-supported ionic liquid catalysts prepared by sol-gel method

박대원,Mi-Kyung Lee,Hye-Lim Shim,Manju Mamparambath Dharman,Kyung-Hoon Kim,박상욱 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.5

A silica-supported ionic liquid (Im-IL) was proven to be an effective heterogeneous catalyst for solventless synthesis of cyclic carbonate from allyl glycidyl ether (AGE) and carbon dioxide. Im-IL catalysts were prepared by sol-gel method. The synthesis of cyclic carbonate from AGE and CO2 was carried out in a batch autoclave reactor. Im-IL with shorter alkyl chain length showed the highest conversion of AGE, probably due to the steric hindrance for the formation of intermediate from the catalyst prepared by using longer alkyl chains and AGE. High temperature and high pressure were favorable for the conversion of AGE. Im-IL can be reused for the reaction up to two consecutive runs without any considerable loss of its catalytic activity.

Cycloaddition of carbon dioxide to butyl glycidyl ether using imidazolium salt ionic liquid as a catalyst

박대원,Jeong-In Yu,Hye-Young Ju,Kyung-Hoon Kim 한국화학공학회 2010 Korean Journal of Chemical Engineering Vol.27 No.2

The catalytic performance of imidazolium salt ionic liquids in the cycloaddition of carbon dioxide to butyl glycidyl ether (BGE) was investigated. The catalytic activity was tested with different imidazolium salt ionic liquids at 60-140 oC under 0.62-2.17MPa of CO2 pressure. The imidazolium salt ionic liquid with the cation of bulkier alkyl chain length and with more nucleophilic anion showed higher conversion of BGE. High carbon dioxide pressure and high reaction temperature up to 140 oC was favorable for the high reactivity of the catalyst. The presence of zinc bromide co-catalyst enhanced the reactivity of the imidazolium salt ionic liquid. Kinetic studies with a semi-batch reactor revealed that the reaction could be considered as first order with respect to the concentration of BGE, and the activation energy was estimated as 22.6 and 22.8 kJ/mol for 1-ethyl-3-methylimidazolium chloride (EMImCl) and 1-butyl-3-methylimidazolium chloride (BMImCl), respectively.

Chemical fixation of carbon dioxide to dimethyl carbonate from propylene carbonate and methanol using ionic liquid catalysts

박대원,Hye-Young Ju,Mamparambath Dharman Manju,Kyung-Hoon Kim,박상욱 한국화학공학회 2007 Korean Journal of Chemical Engineering Vol.24 No.5

with methanol was investigated by using imidazolium salt ionic liquid catalysts. 1-alkyl-3-methyl imidazolium saltsof different alkyl group (C2, C4, C6, C8) and anions (Cl, Br,BF4, PF6) were used for catalysts. The reaction was carriedout in an autoclave at 140-180oC under carbon dioxide pressure of 1.48-5.61 MPa. The imidazolium salts of shorteras CO2 pressure and reaction temperature increased. Kinetic studies were also performed to better understand the reac-tion mechanism.

Effect of cocatalyst and carbon dioxide pressure on the synthesis of polycarbonate from phenyl glycidyl ether and carbon dioxide

박대원,Ji-Yeon Ahn,Hye-Lim Shim,Kyung-Hoon Kim,김일,박상욱 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.4

The copolymerization of phenyl glycidyl ether (PGE) and carbon dioxide was performed in the presence of ionic liquid catalyst. 1-Butyl-3-methyl imidazolium chloride, tetrabutylamouim chloride and 1-n-butylpyridinium chloride were used as catalyst for this reaction carried out in a batch reactor. All the ionic liquid catalysts showed good catalytic activity for the synthesis of polycarbonates with very low polydispersity, close to 1. The carbonate content, turnover number (TON), and average molecular weight of the copolymer were affected by the structure of the ionic liquid. High carbon dioxide pressure enhanced TON and carbonate content because of the increase of carbon dioxide absorption in PGE solution. ZnBr2 and a Zn-Co cyanide complex were also tested as a catalyst and/or cocatalyst for this reaction to compare their catalytic performance with the imidazolium salt ionic liquids

12-몰리브도 인산 동염 촉매상에 서 아크롤레인의 선택 산화반응

김경훈,나석은,박대원 ( Kyung Hoon Kim,Suk Eun Na,Dae Won Park ) 한국공업화학회 1993 공업화학 Vol.4 No.4

Cu_xH_3-2_xPMo_(12)O_(40)·_nH_20에서 구리의 치환양 x를 변화시켜 여러 가지의 헤테로폴리산 동염 촉매를 제조하고, 열분석, X-선 회절분석, 적외선 분광분석, 비표면적 측정, 전자현미경 분석, 암모니아의 승온탈착법 등으로 촉매의 특성을 조사하였다. 아크롤레인의 산화반응에 대한 이 촉매계의 반응특성은 고정층 연속반응기에서 조사하였다. 이 촉매들은 200℃ 근처에서 결정수의 탈리가 일어났고 구리의 치환에 따른 구조수의 탈리는 300∼400℃ 사이에서 관찰되었다. 이들 촉매는 Keggin 구조를 가짐을 확인할 수 있었고, 구리의 치환양이 증가함에 따라 Keggin 음이온인 (PMo_(12)0(40))^(3-)의 분해 정도가 증가하였으며, 이때 분해 생성물로 소량의 MoO_3와 P_2O_5가 관찰되었다. X가 증가할수록 아크롤레인의 전화율이 감소하였는데 이것은 비표면적과 전체 산점의 양이 감소하였기 때문인 것으로 판단된다. 그러나 단위면적당 반응속도와 아크릴산의 선택도는 x=1.0에서 가장 높게 나타났으며 이 촉매는 독특한 산점분포를 나타내었다. Various catalysts of Cu_kH_3-(2x)PMo_(12)O_(40)·nH_2O with different x-values have been prepared and characterized by thermal analysis, X-ray powder diffraction, infrared spectroscopy, BET surface-area measurement, electron micros-copy, and temperature programmed desorption of ammonia. The properties of these catalysts in acrolein oxidation have been investigated in a continuous-flow fixed-bed reactor. The catalysts lost their water of crystallization at about 200℃ and their constitutional water between 300 and 400℃. The Keggin structure of the catalysts was identified by infrared spectroscopy. The decomposition of Keggin anion, (PMo_(12)O(40))^(3-), was increased with the increase of substituted copper content and identifiable MoO_3 and P_2O_5 as decomposition products were observed. The conversion of acrolein decreased with the increase of x probably due to the decrease of specific surface area and of total amount of acid sites. But specific reaction rate and selectivity to acrylic acid were maximized at x= 1.0, and it showed specific acid site distributions.

아크로레인 산화용 Mo - V 계 혼합산화물 촉매의 상승효과 (Ⅰ)

나석은,김경훈,정종식,박대원 ( Suk Eun Na,Kyung Hoon Kim,Jong Shik Chung,Dae Won Park ) 한국공업화학회 1992 공업화학 Vol.3 No.4

공침법으로 제조한 vanadium molybdate와 copper molybdate촉매의 기계적 혼합물과 V_2O_5와 MoO_3의 기계적 혼합물을 아크로레인의 선택 산화반응용 촉매로 사용하여 각각의 금속산화물 사이의 상승효과에 대하여 고찰하였다. 반응실험 결과 혼합촉매를 사용한 경우 아크로레인의 전화율과 아크릴산의 수율이 증가하였으며 이는 remote control mechanism으로 설명할 수 있었다. 열중량 분석결과 혼합촉매에서 격자산소가 방출됨을 확인할 수 있었다. Mechanical mixtures of vanadium molybdate and copper molybdate catalysts prepared by coprecipitation method, and those of MoO_3 and V_2O_5 were used to study the synergistic effects between each metal oxide for the selective oxidation of acrolein. The catalytic activity results revealed that the conversion of acrolein and yield of acrylic acid were incresed with the mixture catalysts and it could be explained by a remote control mechanism. Thermal gravimetric analysis confirmed the evolution of lattice oxygen in the mixture catalysts.