• Environmental Engineering Research
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• 제12권5호
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• pp.211-217
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• 2007

Polycyclic aromatic hydrocarbon growth from cyclopentadiene (CPD) pyrolysis was investigated using a laminar flow reactor operating in a temperature range of 600 to $950^{\circ}c$. Major products from CPD pyrolysis are benzene, indene and naphthalene. Formation of observed products from CPD is explained as follows. Addition of the cyclopentadienyl radical to a CPD $\pi$-bond produces a resonance-stabilized radical, which further reacts by one of three unimolecular channels: intramolecular addition, C-H bond $\beta$-scission, or C-C bond $\beta$-scission. The intramolecular addition pathway produces a 7-norbornenyl radical, which then decomposes to indene. Decomposition by C-H bond $\beta$-scission produces a biaryl intermediate, which then undergoes a ring fusion sequence that has been proposed for dihydrofulvalene-to-naphthalene conversion. In this study, we propose C-C bond $\beta$-scission pathway as an alternative reaction channel to naphthalene from CPD. As preliminary computational analysis, Parametric Method 3 (PM3) molecular calculation suggests that intramolecular addition to form indene is favored at low temperatures and C-C bond $\beta$-scission leading to naphthalene is predominant at high temperatures.

• Bulletin of the Korean Chemical Society
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• 제25권4호
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• pp.533-538
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• 2004

Canonical sampling method has been presented to generate the initial conditions for reactive flux studies of organic reactions in water. Velocity Verlet version of Nose-Hoover chain dynamics algorithm has been employed to sample the initial conditions according to canonical distribution. The unstable normal mode of a transition state has been introduced to define a dividing plane separating reactant and product regions in reaction processes. This method has been implemented and tested for the case iels-Alder reaction of methyl vinyl ketone (MVK) and cyclopentadiene (CPD) in water, providing a reliable tool for further reactive flux molecular dynamics studies in condensed media.

• 공업화학
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• 제25권1호
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• pp.66-71
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• 2014

HY 제올라이트 촉매 상에서 endo-THDCPD의 이성화 반응을 통한 exo-THDCPD 제조에 관한 연구를 수행하였다. HY 제올라이트 촉매의 $Si/Al_2$ 비가 증가할 때 endo-THDCPD의 전환율이 증가하는 경향을 보였는데 이는 산점의 세기가 증가했기 때문으로 해석할 수 있다. 그러나 $Si/Al_2$ 비가 30인 HY 제올라이트 촉매를 사용한 경우에 최대의 exo-THDCPD 수율을 얻을 수 있었는데, 부산물인 CPD와 oligomer의 생성이 적기 때문으로 해석할 수 있다. 반응 온도가 증가할수록 부산물 생성이 증가하는 것을 고려하여 $180^{\circ}C$를 최적 반응 온도로 선정할 수 있었다. 촉매의 함량을 증가시키면 exo-THDCPD 수율을 증가시킬 수 있다. HY 제올라이트 촉매를 사용한 endo-THDCPD의 이성화 반응에서 촉매 외부확산 저항보다 촉매 기공 내부확산 저항이 반응 활성에 더 큰 영향을 미친다는 것을 확인할 수 있었다.