금속이온 교환 천연 제올라이트에 의한 o-Xylene의 이성질화 반응

이재영; 심미자; 김상욱

Journal of the Korean Industrial and Engineering Chemistry, Vol.6, No.4, 658-663, August, 1995

Export Citation

금속이온 교환 천연 제올라이트에 의한 o-Xylene의 이성질화 반응

Isomerization of o-Xylene on the Metal Ion-exchanged Natural Zeolite

이재영, 심미자, 김상욱

초록

금속이온이 교환된 천연제올라이트에 의한 o-xylene의 이성질화 반응을 연구하였다. 또한, 자일렌의 이성화 반응과 밀접한 관계가 있는 제온라이트 촉매의 산특성도 조사하였다. Na⁺, K⁺, Cs⁺ 금속이온이 교환된 시료의 산성도는 양이온의 크기가 증가함에 따라 감소하였고, Mg²⁺, Ca²⁺, Ba²⁺ 금속이온이 교환된 경우는 양이온의 크기가 증가함에 따라 산성도가 약간 증가하였다. 이성화 반응이 진행됨에 따라 제올라이트 표면에 코크가 침적되어 반응물이 활성점에 확산되어 가는 것을 방해하며, 이로인해 o-xylene의 전환율이 급격히 감소하였다. 금속이온 교환된 시료에서 산성도가 감소함에 따라 o-xylene의 전환율은 감소하였고, p-xylene의 선택도는 증가하였다. 이 결과로부터 xylene의 전환율과 선택도는 산성도와 밀접한 관계가 있음을 알 수 있다.

Isomerization of o-xylene on the metal ion-exchanged natural zeolite and the acid property of these catalysts which was closely related to the isomerization of xylene were studied. With the exchange of metal ion by Na⁺, K⁺ and Cs⁺, the acidity was decreased with increasing cation size, but with the exchange by Mg²⁺, Ca²⁺and Ba²⁺, slight increase of acidity was found. As reaction time of isomerization was increased, coke was deposited on the surface of zeolite so that the diffusion of reactant onto the active site was disturbed and the conversion of o-xylene was reduced rapidly. When metal ions were exchanged, the conversion of o-xylene was decreased with decrease of the acidity and the selectivity of p-xylene was increased. From these results, it could be found that the conversion and the selectivity of xylene were closely related to the acidity of zeolite catalyst.

[References]

Lee JY, Shim MJ, Kim SW, J. Korean Ind. Eng. Chem., 5(6), 1024 (1994)
Lee JY, Lee HK, Lee JS, Shim MJ, Kim SW, J. Korean Inst. Surf. Eng., 26, 285 (1993)
Young LB, Butter SA, Kaeding WW, J. Catal., 76, 418 (1982)
Subhash B, "Zeolite Catalysis : Principles and Applications," 164, CRC Press, Inc., Boca Raton, Florida (1990)
Kaeding WW, Chu C, Young LB, Weinstein B, Butter SA, J. Catal., 67, 159 (1981)
Cortes A, Corma A, J. Catal., 51, 338 (1978)
Allen RH, J. Am. Chem. Soc., 82, 4856 (1960)
Silvestri AJ, Prater CD, J. Phys. Chem., 68, 3268 (1964)
Lee HK, Shim MJ, Kim SW, J. Korean Ind. Eng. Chem., 6(1), 49 (1995)
Lee HK, Shim MJ, Lee JS, Kim SW, "Materials Chemistry and Physics," in Press (1995)
Inui T, Matsuda H, Yamase O, Nagata H, Fukuda K, Ukawa T, Mitamoto A, J. Catal., 98, 491 (1986)
Shashldhar SB, Patwardhan R, Ind. Eng. Chem. Prod. Res. Dev., 20, 102 (1981)
Barthomeuf D, J. Phys. Chem., 88, 2 (1984)
Lee HK, Lee JS, Shim MJ, Kim SW, IUMRS-ICA-94, in press (1995)

[1] Lee JY, Shim MJ, Kim SW, J. Korean Ind. Eng. Chem., 5(6), 1024 (1994)

[2] Lee JY, Lee HK, Lee JS, Shim MJ, Kim SW, J. Korean Inst. Surf. Eng., 26, 285 (1993)

[3] Young LB, Butter SA, Kaeding WW, J. Catal., 76, 418 (1982)

[4] Subhash B, "Zeolite Catalysis : Principles and Applications," 164, CRC Press, Inc., Boca Raton, Florida (1990)

[5] Kaeding WW, Chu C, Young LB, Weinstein B, Butter SA, J. Catal., 67, 159 (1981)

[6] Cortes A, Corma A, J. Catal., 51, 338 (1978)

[7] Allen RH, J. Am. Chem. Soc., 82, 4856 (1960)

[8] Silvestri AJ, Prater CD, J. Phys. Chem., 68, 3268 (1964)

[9] Lee HK, Shim MJ, Kim SW, J. Korean Ind. Eng. Chem., 6(1), 49 (1995)

[10] Lee HK, Shim MJ, Lee JS, Kim SW, "Materials Chemistry and Physics," in Press (1995)

[11] Inui T, Matsuda H, Yamase O, Nagata H, Fukuda K, Ukawa T, Mitamoto A, J. Catal., 98, 491 (1986)

[12] Shashldhar SB, Patwardhan R, Ind. Eng. Chem. Prod. Res. Dev., 20, 102 (1981)

[13] Barthomeuf D, J. Phys. Chem., 88, 2 (1984)

[14] Lee HK, Lee JS, Shim MJ, Kim SW, IUMRS-ICA-94, in press (1995)