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Heterogeneous Catalytic Oligomerization of Ethylene.

Record Type:	Language materials, manuscript : Monograph/item
Title/Author:	Heterogeneous Catalytic Oligomerization of Ethylene./
Author:	Jan, Oliver Dennis.
Description:	1 online resource (133 pages)
Notes:	Source: Dissertation Abstracts International, Volume: 78-12(E), Section: B.
Contained By:	Dissertation Abstracts International78-12B(E).
Subject:	Chemical engineering. -
Online resource:	click for full text (PQDT)
ISBN:	9780355119060

Heterogeneous Catalytic Oligomerization of Ethylene.
Jan, Oliver Dennis.

Heterogeneous Catalytic Oligomerization of Ethylene. - 1 online resource (133 pages)

Source: Dissertation Abstracts International, Volume: 78-12(E), Section: B.

Thesis (Ph.D.)

Includes bibliographical references

Throughout this work, we report results for the oligomerization of ethylene over Ni-Hbeta in a packed bed reactor. We performed a parameterized study over temperature (30ºC-190ºC), pressure (8.5-25.6 bar), and weighted hourly space velocity (2.0-5.5 hr-1). We observed that the ethylene conversion increased with reaction pressure due primarily to the slower velocities at higher pressures. Increasing the temperature of the reactor led to the formation of larger oligomers and coke, but its effect on the conversion was small. The space velocity played an important role on ethylene conversion and product selectivity, with higher conversions observed at lower space velocities and higher selectivities to butene at higher space velocities. We also conducted a long experiment to determine the activity of the Ni-Hbeta catalyst over 72 hours-on-stream at 19.0 bar partial pressure of ethylene, 120ºC, and 3.1 hr-1 WHSV. We observed that catalyst deactivation occurred only during the startup period largely due to coke formation. Despite this initial deactivation, negligible coke formation occurred after 8 hours time-on-stream, as the conversion remained steady at 47% for the duration of the experiment.

Electronic reproduction.
Ann Arbor, Mich. :
ProQuest,
2018

Mode of access: World Wide Web

ISBN: 9780355119060Subjects--Topical Terms:

555952
Chemical engineering.
Index Terms--Genre/Form:

554714
Electronic books.

Heterogeneous Catalytic Oligomerization of Ethylene.
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020 $a 9780355119060
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035 $a AAI10224356
040 $a MiAaPQ $b eng $c MiAaPQ
099 $a TUL $f hyy $c available through World Wide Web
100 1 $a Jan, Oliver Dennis. $3 1179626
245 1 0 $a Heterogeneous Catalytic Oligomerization of Ethylene.
264 0 $c 2017
300 $a 1 online resource (133 pages)
336 $a text $b txt $2 rdacontent
337 $a computer $b c $2 rdamedia
338 $a online resource $b cr $2 rdacarrier
500 $a Source: Dissertation Abstracts International, Volume: 78-12(E), Section: B.
500 $a Adviser: Fernando Resende.
502 $a Thesis (Ph.D.) $c University of Washington $d 2017.
504 $a Includes bibliographical references
520 $a Throughout this work, we report results for the oligomerization of ethylene over Ni-Hbeta in a packed bed reactor. We performed a parameterized study over temperature (30ºC-190ºC), pressure (8.5-25.6 bar), and weighted hourly space velocity (2.0-5.5 hr-1). We observed that the ethylene conversion increased with reaction pressure due primarily to the slower velocities at higher pressures. Increasing the temperature of the reactor led to the formation of larger oligomers and coke, but its effect on the conversion was small. The space velocity played an important role on ethylene conversion and product selectivity, with higher conversions observed at lower space velocities and higher selectivities to butene at higher space velocities. We also conducted a long experiment to determine the activity of the Ni-Hbeta catalyst over 72 hours-on-stream at 19.0 bar partial pressure of ethylene, 120ºC, and 3.1 hr-1 WHSV. We observed that catalyst deactivation occurred only during the startup period largely due to coke formation. Despite this initial deactivation, negligible coke formation occurred after 8 hours time-on-stream, as the conversion remained steady at 47% for the duration of the experiment.
520 $a We also carried out oligomerization of ethylene using Ni-Hbeta in a laboratory-scale packed bed reactor for the synthesis of liquid hydrocarbons. We evaluated the effect of several process variables (temperature, pressure, weighted hourly space velocity, and nickel loading) on the liquid hydrocarbon/coke yield, ethylene conversion, and oligomeric product selectivity. Increases in pressure resulted in higher ethylene conversion, corresponding to a liquid yield of 12.4 wt.% with 5.7 wt.% coke. As the pressure increased, the selectivity towards octenes doubled alongside a decrease in butenes, which suggested that higher pressures promoted butene dimerization. Under the conditions studied, a minimum temperature of 120ºC was required to produce liquid hydrocarbons. The liquid yield increased with temperature, with 17 wt.% observed at 190ºC. Higher reaction temperatures led to the formation of odd-numbered oligomers primarily due to acid-catalyzed cracking reactions. In the range of space velocities tested, a moderate WHSV of 2.0 hr-1 resulted in a local maximum of 10.6 wt.% of liquid hydrocarbon yield. A moderate nickel loading of 3.4 wt.% also resulted in the highest liquid yield out of the three loadings tested (10.6 wt.%). The variation in nickel loading revealed the importance of having a synergistic balance of nickel and acid sites on the catalyst to maximize ethylene conversion and maintain high liquid hydrocarbon yield.
520 $a Lastly, we used supercritical ethylene as both a solvent and as a reactant for ethylene oligomerization over two silica-alumina type catalysts: Ni-Hbeta and Ni-Al-SBA-15. Specifically, the effect of pressure and temperature on the overall conversion and product selectivity were evaluated in the range from 0 to 65 bar and 30 to 120ºC. At subcritical conditions, the ethylene conversion reached a plateau of around 50%. By increasing the pressure past the critical point of ethylene, the conversion drastically increased to 71%. The increased conversion can be attributed to the solubility of certain oligomers, namely butene, in supercritical ethylene that promotes desorption from catalytic active site before further oligomerization. We also tested a mesoporous catalyst, Ni-Al-SBA-15 and observed conversion trends analogous to that of Ni-Hbeta. At supercritical conditions, ethylene oligomerization over Ni-Al-SBA-15 was more selective towards the butene product, with nearly 74 wt.% butenes observed. The catalyst activity increased with temperature from 30ºC to 120ºC. The experiment conducted at 30ºC showed very little activity and ethylene conversion, however it effectively heavy molecular weight species from the catalyst. This condition, albeit being not effective for ethylene oligomerization, could be implemented as an in-situ technique to regenerate the catalyst during process operation.
533 $a Electronic reproduction. $b Ann Arbor, Mich. : $c ProQuest, $d 2018
538 $a Mode of access: World Wide Web
650 4 $a Chemical engineering. $3 555952
650 4 $a Materials science. $3 557839
655 7 $a Electronic books. $2 local $3 554714
690 $a 0542
690 $a 0794
710 2 $a ProQuest Information and Learning Co. $3 1178819
710 2 $a University of Washington. $b Environmental and Forest Science. $3 1179627
773 0 $t Dissertation Abstracts International $g 78-12B(E).
856 4 0 $u http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=10224356 $z click for full text (PQDT)