RISS 학술연구정보서비스

검색
다국어 입력

http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.

변환된 중국어를 복사하여 사용하시면 됩니다.

예시)
  • 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
  • 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
닫기
    인기검색어 순위 펼치기

    RISS 인기검색어

      검색결과 좁혀 보기

      선택해제

      오늘 본 자료

      • 오늘 본 자료가 없습니다.
      더보기
      • 무료
      • 기관 내 무료
      • 유료
      • KCI등재

        The isopropylation of biphenyl over H-mordenite - Roles of 3- and 4-isopropylbiphenyls

        Yoshihiro Sugi,Chokkalingam Anand,Tomonori Sugimura,Kenichi Komura,Yoshihiro Kubota,Jong Ho Kim,Gon Seo,Ajayan Vinu 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.5

        The isopropylation of biphenyl (BP) and 3- and 4-isopropylbiphenyls (3- and 4-IPBPs) was examined over H-mordenites (MOR) to elucidate the mechanism of shape-selective formation of 4,4'-diisopropylbiphenyl (4,4'-DIPB). The isopropylation of BP occurred predominantly to form 4-isopropylbiphenyl (4-IPBP) from BP and 4,4'-DIPB from 4-IPBP. However, 3-IPBP, a minor isomer from BP, cannot participate effectively in the formation of 3,4'-DIPB due to steric restriction of its isopropyl moiety with MOR channels. Selective formation of 4,4'-DIPB was observed at low to moderate temperatures: 225-275 oC. However, the selectivities for 4,4'-DIPB were decreased at high temperatures,300-350 oC under propene pressure, 0.8MPa, by the isomerization of 4,4'-DIPB at external acid sites. The isomerization of 4,4'-DIPB occurred under low propene pressure even at 250 oC. The roles of 3- and 4-IPBPs in the formation of DIPB isomers were examined in the isopropylation of their mixtures. 4-IPBP was consumed much faster than 3-IPBP in all cases examined. 4-IPBP was an exclusive precursor to DIPB isomers, particularly 4,4'-DIPB. 4,4'-DIPB was also found as a predominant isomer in encapsulated products at all conditions examined. These results show that 4-IPBP can preferentially establish active transition state with propene and acid site in MOR channels, resulting in selective formation of 4,4'-DIPB. It is concluded that the isopropylation of BP over MOR occurs through reactant selectivity mechanism and restricted transition state mechanism, but not through product selectivity mechanism.

      연관 검색어 추천

      이 검색어로 많이 본 자료

      활용도 높은 자료

      해외이동버튼