Highly Active Chromium Catalytic System for Ethylene Tetramerization
- 주제(키워드) ethylene tetramerization , chromium
- 발행기관 아주대학교
- 지도교수 이분열
- 발행년도 2018
- 학위수여년월 2018. 2
- 학위명 석사
- 학과 및 전공 일반대학원 분자과학기술학과
- 실제URI http://www.dcollection.net/handler/ajou/000000026891
- 본문언어 영어
- 저작권 아주대학교 논문은 저작권에 의해 보호받습니다.
초록/요약
Ethylene tetramerization catalyst systems discovered by Sasol consist of Cr(III) source (Cr(acac)3 or CrCl3), PNP ligand (RN(PPh2)2), and MAO are useful for the production of 1-octene through selective ethylene oligomerization. When it comes to the large scale use of the Sasol system, The use of MAO in excess has economic burden because of expensive price of MAO. In this work, we developed a catalytic system using inexpensive alkylaluminum in place of MAO. We prepared catalyst precursors with Cr, PNP ligand([CH3(CH2)16]2CHN(PPh2)2) (1), and [B(C6F5)4]- anion in 1 : 1 : 2 mole ratios. [1-CrAlCl4]2+[B(C6F5)4]-2 exhibited high activity with satisfactory selectivity when activated with common trialkylaluminum species (Et3Al, iBu3Al, and trioctylaluminum) in methylcyclohexane (activated with iBu3Al, 1110 Kg/g-Cr/h; 1-hexene 22%, 1-octene 63%, PE 1.7%). Compared to original Sasol system ((iPrN(PPh2)2)Cr(acac)3/MAO (280 Kg/g-Cr/h; 1-hexene 13%, 1-octene 71%, PE 0.4%)), These selectivity and activity are comparable. Moreover, [1-CrAlCl3(acac)]2+[B(C6F5)4]-2 catalyst system shows higher activity with reasonable selectivity (1400 Kg/g-Cr/h; 1-hexene 17%, 1-octene 68%, PE 0.9%) than [1-CrAlCl4(THF)3]2+[B(C6F5)4]-2 catalyst system.
more목차
1. Introduction 1
2. Results and Discussion 3
2.1 Activity versus Catalyst Composition 3
3. Conclusions 11
4. Experimental Section 12
4.1 General remarks 12
4.2 Synthesis of ligands and complexes 12
4.3 Typical procedure for ethylene oligomerization 16
5. Reference 17
6. Supporting information 24
