Jet fuel range hydrocarbon synthesis through ethylene oligomerization over platelet Ni-AlSBA-15 catalyst

Abstract

Converting ethylene to biojet fuel range hydrocarbons via oligomerization is an important step in biojet production from ethanol. The present study investigates the catalytic ethylene oligomerization over platelet Ni-AlSBA-15 mesoporous catalysts. The catalysts are synthesized and characterized using nitrogen adsorption-desorption isotherms, X-ray fluorescence and X-ray diffraction techniques. The catalytic performances are then evaluated in a continuous flow fixed-bed reactor under various conditions of reaction weight hourly space velocities (0.56-4.5 h −1), temperatures (150-350 °C) and pressures (1-20 bar). Experimental results demonstrate that platelet Ni-AlSBA-15 is a promising catalyst for the ethylene oligomerization to produce biojet fuel range hydrocarbons. It performs a good catalytic activity, yielding 98-99 mol% ethylene conversion and 34-42 wt% C 8+ selectivity at 0.56 h −1 , 275-300 °C and 20 bar. The obtained products contain mainly C 4-C 10 olefins with low aromatic compounds. Moreover, the catalyst exhibits good stability of the activity during long periods of operation.

Novel Ni-SIRAL Catalyst for Heterogeneous Ethylene Oligomerization

“…In addition, this is the first work that reports the substantial production of cycloalkanes during heterogeneous ethylene oligomerization with nickel catalysts. The fact that the Ni-SIRAL catalyst exhibits such high conversion at a much higher WHSV shows that this catalyst reaches a higher number of turnovers (12.3 h –1 × 0.91 = 11.2 g of ethylene/g cat./h) compared to the Ni-AlSBA-15 catalyst (4.5 h –1 × 0.65 = 2.9 g of ethylene/g cat./h) reported by Attanatho et al and the Ni-SIRAL catalyst (0.75 h –1 × 0.80 = 0.6 g of ethylene/g cat./h) reported by Lee et al Previous literature reports also show that liquid yields drastically decrease with WHSV during ethylene oligomerization. For instance, Chen et al show that the yield of liquid hydrocarbons (comprising C 5 + products) decreases sharply from 40 wt % at a WHSV of 1.5 h –1 to 20 wt % at a WHSV of 3.8 h –1 during ethylene oligomerization with a nickel-based silica–alumina catalyst at 120 °C and 35 bar.…”

“…The Ni-SIRAL catalyst reported in the present study has superior performance relative to previous nickel-based heterogeneous catalysts reported in the literature. For instance, Attanatho et al 68 reported an ethylene conversion of 65 wt %, with a liquid yield of only 19 wt % using a Ni-AlSBA-15 catalyst at 300 °C and 20 bar. The Ni-SIRAL catalyst presented in our work displays a much higher ethylene conversion, 91 wt %, with a higher liquid yield, 42 wt %, operating at a lower temperature, 200 °C, and higher weight hour space velocity (WHSV), 12.3 h −1 .…”

Geospatial Network Approach for Assessing Economic Potential of Ethylene-to-Fuel Technology in the Marcellus Shale Region

“…Nevertheless, if the ethylene oligomerization technology were adopted on a larger scale, reduced output of refinery coproducts may still become an issue of concern. This may motivate additional technology developments for converting NGL-based feedstocks such as light alkenes into diesel and jet fuel. , …”

“…9 While ethylene is a key petrochemical feedstock for producing polyethylene, ethylene glycol, styrene, and many other derivatives, the unprecedented growth in ethylene production, driven by the availability of abundant and lowcost NGLs, has led to concerns about its overproduction and the presence of excess capacity. 10 A potential high volume use for ethylene is the production of liquid transportation fuels, such as jet fuel 11 and gasoline. 5 Our focus in this work is on the oligomerization of ethylene to gasoline or a gasoline blend stock.…”

Systems Analysis of Natural Gas Liquid Resources for Chemical Manufacturing: Strategic Utilization of Ethane

“…The boom in the production of shale gas and, consequently, NGLs is thus providing a unique opportunity to expand the U.S. chemical industry and is motivating the development of new technologies for using NGLs. This has prompted a number of studies on how to best exploit natural gas and NGL resources for chemical and/or fuel production. − …”