ZSM-5 위에 지지된 Heteropolyacid 하에서 Methacrylic acid와 Ethylene glycol의 에스테르화 반응 Esterification of Methacrylic acid with Ethylene glycol over Heteropolyacid supported on ZSM-5원문보기
Prabhakarn, A.
(Department of Chemistry, Indian Institute of Technology Hyderabad)
,
Fereiro, J.A.
(Department of Chemistry, Indian Institute of Technology Hyderabad)
,
Subrahmanyam, Ch.
(Department of Chemistry, Indian Institute of Technology Hyderabad)
methacrylic acid과 ethylene glycol과의 에스테르화 반응을 ZSM-5에 지지된 heteropolyacids [HPA: $H_4SiW_{12}O_{40}$(STA)와 $H_3PW_{12}O_{40}$(PTA)] 하에서 수행하였다. 비교를 위하여, 지지하지 않은HPA, $H_2SO_4$, $BF_3$와 PTSA 하에서 같은 반응을 수행하였다. 연구한 촉매 중에서, HPA는 $H_2SO_4$, $BF_3$와 PTSA와 비교하여 더 좋은 활성을 보여주었다. 촉매 활성을 HPA지지 ZSM-5 촉매와 비교하였는데, 그 결과 ZSM-5위에 지지된 30 wt% PTA는 bulk PTA와 거의 같은 활성을 나타내었다. 이 반응은 methacrylic acid에 관하여 1차 속도 법칙을 따랐으며, 반응 생성물은 $^1H$-NMR과 FT-IR을 이용하여 확인하였다.
methacrylic acid과 ethylene glycol과의 에스테르화 반응을 ZSM-5에 지지된 heteropolyacids [HPA: $H_4SiW_{12}O_{40}$(STA)와 $H_3PW_{12}O_{40}$(PTA)] 하에서 수행하였다. 비교를 위하여, 지지하지 않은HPA, $H_2SO_4$, $BF_3$와 PTSA 하에서 같은 반응을 수행하였다. 연구한 촉매 중에서, HPA는 $H_2SO_4$, $BF_3$와 PTSA와 비교하여 더 좋은 활성을 보여주었다. 촉매 활성을 HPA지지 ZSM-5 촉매와 비교하였는데, 그 결과 ZSM-5위에 지지된 30 wt% PTA는 bulk PTA와 거의 같은 활성을 나타내었다. 이 반응은 methacrylic acid에 관하여 1차 속도 법칙을 따랐으며, 반응 생성물은 $^1H$-NMR과 FT-IR을 이용하여 확인하였다.
Esterification of methacrylic acid with ethylene glycol was carried out over Heteropolyacids [HPA: $H_4SiW_{12}O_{40}$ (STA) and $H_3PW_{12}O_{40}$ (PTA)] supported on ZSM-5. For comparison, the same reaction was carried out over unsupported HPA, $H_2SO_4$, $BF_...
Esterification of methacrylic acid with ethylene glycol was carried out over Heteropolyacids [HPA: $H_4SiW_{12}O_{40}$ (STA) and $H_3PW_{12}O_{40}$ (PTA)] supported on ZSM-5. For comparison, the same reaction was carried out over unsupported HPA, $H_2SO_4$, $BF_3$ and PTSA. Among the catalysts studied, HPA showed better activity compared to $H_2SO_4$, $BF_3$ and PTSA. Catalytic activity was compared with HPA supported ZSM-5 catalysts. Typical results indicated that 30 wt% PTA supported on ZSM-5 showed nearly the same activity as that of bulk PTA. It was found that the reaction follows first order kinetics with respect to methacrylic acid. The reaction products were identified by $^1H$-NMR and FT-IR.
Esterification of methacrylic acid with ethylene glycol was carried out over Heteropolyacids [HPA: $H_4SiW_{12}O_{40}$ (STA) and $H_3PW_{12}O_{40}$ (PTA)] supported on ZSM-5. For comparison, the same reaction was carried out over unsupported HPA, $H_2SO_4$, $BF_3$ and PTSA. Among the catalysts studied, HPA showed better activity compared to $H_2SO_4$, $BF_3$ and PTSA. Catalytic activity was compared with HPA supported ZSM-5 catalysts. Typical results indicated that 30 wt% PTA supported on ZSM-5 showed nearly the same activity as that of bulk PTA. It was found that the reaction follows first order kinetics with respect to methacrylic acid. The reaction products were identified by $^1H$-NMR and FT-IR.
* AI 자동 식별 결과로 적합하지 않은 문장이 있을 수 있으니, 이용에 유의하시기 바랍니다.
제안 방법
HPA supported on micro porous ZSM-5 catalyst was prepared and studied for this reaction. A detailed kinetic study was carried out in order to understand the nature of the reaction.
대상 데이터
The HPA (silicotungstic acid (STA) and phosphotungstic acid (PTA)) were obtained from Sigma Aldrich and and ZSM-5 was purchased from S□D Cheme and has a surface area of 320 m2 /g.
이론/모형
The supported catalysts were preprered by impregnation method. A series of catalyst containing 10-50 wt% HPA were synthesized by suspending the required amount of ZSM-5 in an aqueous solution of HPA with stirring for 30 h and dried at 373 K for 10 h.
성능/효과
Esterification reaction has been carried out over PTA supported ZSM-5 at 373 K and results are presented in Fig. 6. It is worth mentioning that activity of unmodified ZSM-5 is negligible compared to HPA supported ZSM-5, which may be attributed to lack sufficient number of acidic sites. However, as seen from the Fig.
In order to overcome the practical limitations of HPA like recovery of the catalyst, HPA were supported on ZSM-5 to make the system truly heterogeneous. Typical results indicate that 30 wt% PTA supported on ZSM-5 showed nearly the same activity as that of bulk PTA and with further increase in the PTA loading decreases the activity. The reaction was found to be first order with respect acid.
참고문헌 (22)
Sheldon, R. A.; Downing, R. S. Appl. Cat. A: Gen. 1999, 189, 163.
※ AI-Helper는 부적절한 답변을 할 수 있습니다.