[Due to the increasing size of the archives, each topic page now contains only the prior 365 days of content. Access to older stories is now solely through the Monthly Archive pages or the site search function.]
Study suggests GTL-naphtha-gasoline-ethanol blends can function as well as gasoline with lower emissions
February 05, 2017
Results of a study by a team from the University of Birmingham (UK) and Shell Global Solutions suggest that blends of gasoline with gas-to-liquids (GTL) naphtha can perform comparable combustion and full power output to conventional gasoline, with less than 2% difference in normalized ISFC (indicated specific fuel consumption) and gaseous emissions similar to, if not lower than that of conventional gasoline. A paper on their study is published in the journal Fuel.
The GTL Fischer-Tropsch process produces GTL diesel (the cleaner combustion and emissions qualities of which have been well studied), GTL naphtha, GTL kerosene, GTL normal Paraffin and GTL base oils. GTL naphtha mainly contains C4 to C11 hydrocarbons with a high proportions of straight chain paraffins. Although it has a consistent quality and near-zero sulfur and heavy metals, GTL naphtha has a low octane rating, making it unsuitable for blending in gasoline. (GTL naphtha currently is used as an alternative high-quality feedstock for plastics.) However, that low octane rating can be addressed by using ethanol as an octane booster.
Researchers clarify role of cetane number and aromaticity in soot-NOx tradeoff
August 22, 2016
A study by researchers at Eindhoven University of Technology has found that the “persistent diesel dogma” of “the higher the cetane number (CN) the better” relative to the soot-NOx trade-off is valid in neither conventional or low temperature combustion operation. The open-access study, published in the journal Fuel also reported that a second piece of conventional wisdom—“the lower the aromaticity the better”— is valid in both combustion modes.
The researchers also devised a new, dimensionless parameter—Π—that holds distinct values for the various combustion modes. This can predict either a positive, neutral or negative impact of high CN and low aromaticity on the soot-NOx trade-off based on a given set of engine operating conditions.
New ceramic membrane enables first direct conversion of methane to liquids without CO2 emissions
August 05, 2016
A team from CoorsTek Membrane Sciences, the University of Oslo (Norway), and the Instituto de Tecnología Química (ITQ) (Spain) has developed a new process for the direct, non-oxidative conversion of methane to liquids—reducing cost, eliminating multiple process steps, and avoiding CO2 emissions.
The process uses a novel ceramic membrane that simultaneously extracts hydrogen and injects oxide ions. The resulting aromatic precursors are source chemicals for insulation materials, plastics, textiles, and jet fuel, among other valuable products. A paper describing the process is published in the journal Science.
Siluria Technologies and Air Liquide partner to develop and deliver novel catalytic process technologies to global energy markets
June 07, 2016
Siluria Technologies has entered into a strategic partnership with Air Liquide Global E&C Solutions, the engineering and construction business of the Air Liquide Group, to collaborate on the development of novel catalytic processes utilizing both companies’ expertise in gas conversion technologies.
The novel process offering will be developed using the proven innovation platform that has given rise to Siluria’s revolutionary Oxidative Coupling of Methane (OCM) technology (earlier post), but will be focused on entirely new fields beyond the companies’ current product offerings. Siluria and Air Liquide Global E&C Solutions have agreed to work as partners in the commercialization—including marketing and licensing—of the jointly developed process technologies resulting from the collaboration.
U Mich study explores performance of renewable diesel, FT diesel and ULSD in PCCI combustion
May 03, 2016
A team at the University of Michigan has investigated the performance of three different fuels—ultralow sulfur diesel (ULSD), diesel fuel produced via a low temperature Fischer–Tropsch process (LTFT), and a renewable diesel (RD), which is a hydrotreated camelina oil under partially premixed compression ignition (PCCI) combustion. Their paper is published in the ACS journal Energy & Fuels.
Partially premixed compression ignition (PCCI) combustion is an advanced, low-temperature combustion mode that creates a partially premixed charge inside the cylinder before ignition occurs. PCCI prolongs the time period for mixing of the fuel–air mixture by separating the end of injection and start of combustion. As a result, NOx and particulate matter (PM) emissions can be reduced simultaneously relative to those of conventional diesel combustion.