Impact of Alternative Fuel Blending Components on Fuel Composition

Home Screen Newspaper. No matches found. No publications added. Journals. Books. Book Series. Working Papers. If it takes too long to load the home pa...
1 downloads 0 Views 3MB Size
Download PDF
Article pubs.acs.org/EF

Cite This: Energy Fuels XXXX, XXX, XXX−XXX

Impact of Alternative Fuel Blending Components on Fuel Composition and Properties in Blends with Jet A Petr Vozka,† Dan Vrtiška,‡ Pavel Š imać ě k,‡ and Gozdem Kilaz*,† †

School of Engineering Technology, Fuel Laboratory of Renewable Energy, Purdue University, West Lafayette, Indiana 47906, United States ‡ Department of Petroleum Technology and Alternative Fuels, University of Chemistry and Technology, 16628 Prague 6, Czech Republic

Energy Fuels Downloaded from pubs.acs.org by UNIV OF TOLEDO on 03/17/19. For personal use only.

S Supporting Information *

ABSTRACT: One challenge in the deployment of alternative aviation fuels is the lengthy “fuel approval process”, which costs millions of dollars and can take many years as the exact effect of these alternative options on engine and framework is still an unknown. A candidate aviation fuel needs to pass the tests as deemed necessary by the ASTM D4054 Standard Practice. The fuel manufacturer faces the risk of not receiving the ASTM certification after significant financial and time investment, which currently acts as a considerable hindrance to broadening the alternative aviation fuel options in commercial and military aircraft. Approval tests are based on the fuel properties and fuel performance as there is currently a knowledge gap on fuel chemical composition−property correlations. Therefore, the aim of this study was to accomplish the first step in this target, i.e., to obtain a detailed chemical composition of four approved blending components (FT-SPK, HEFA, SIP, and ATJ) and their mixtures with Jet A using GC × GC-TOF/MS and GC × GC-FID. Infrared spectroscopy and principal components analysis were utilized as additional techniques to demonstrate the differences among the blending components and Jet A, further utilizing their infrared spectral features. Moreover, the main physiochemical properties were measured, such as distillation profile, density, viscosity, flash point, freezing point, and net heat of combustion. Lastly, the impact of the differences in chemical composition on these main fuel properties was discussed.

■

INTRODUCTION

The data developed from the ASTM D4054 process is included in “Research Reports” used to support consensus ballots to add alternative fuels to ASTM D7566, separated by production process (as opposed to feedstock). Fuels are added as annexes, with ASTM D7566 currently containing five approved annexes, as shown in the Table 1 below. Currently, the Research Reports provide detailed information on five nonpetroleum-source-derived blending components for their use in jet fuel.2 Fischer−Tropsch hydroprocessed synthesized paraffinic kerosene (FT-SPK) was certified as the first nonpetroleum-originated synthetic blending component for civil jet fuels in 2009. According to the limitations defined in ASTM D7566, FT-SPK may only be used after blending up to a maximum ratio of 50 vol % with the conventional jet fuels. Current commercial plants that produce synthetic jet fuels and fuel blending components via FT technology utilize only coal (e.g., Sasol IPK) and natural gas (e.g., Syntroleum S-8, Shell GTL) as the feedstock. As biomass has not yet been utilized as one of the feedstocks, alternative jet fuels manufactured via FT technology does not reduce the carbon footprint of air transportation even though FT offers a nonpetroleum pathway.3,4 Synthesized paraffinic kerosene from hydroprocessed esters and fatty acids (HEFA) is currently the second nonpetroleum blending component approved by ASTM in 2011. Content of HEFA in jet fuels is

There are three main governing ASTM standards with regards to aviation fuel certification and deployment, namely, ASTM D1655 (Aviation Turbine Fuels), D7566 (Aviation Turbine Fuel Containing Synthesized Hydrocarbons), and D4054 (Evaluation of New Aviation Turbine Fuels and Fuel Additives). D1655 is the protocol for petroleum-derived aviation fuels, while D7566 focuses on the alternative options. All candidate alternative aviation fuels have to be evaluated through an approval process D4054, which is composed of four main tiers of testing, i.e., (i) fuel specification properties, (ii) fit-for-purpose properties, (iii) components tests, and (iv) engine test. Tier 1 testing should be performed on the candidate fuel as well as on the final blend.1 Here, it should be noted that none of the fuel candidates submitted to ASTM were approved without further blending with petroleum-based jet fuels; hence, it is referred to as a “synthetic blending component”. Based on the results from tier 1 testing, the Original Equipment Manufacturers (OEMs) will suggest on which additional test should be performed in tiers 2, 3, and 4. Once the blending component is approved, it is included in D7566 standard along with the maximum blending ratio. Approved fuels are then recertified as ASTM D1655. The reason that the approval process does not lead directly to ASTM D1655 is that ASTM D7566 imposes stricter limits on the alternative fuels and blends as a risk reduction measure. Those limits were not intended to apply to conventional (petroleum-derived) aviation fuels. © XXXX American Chemical Society

Received: January 10, 2019 Revised: February 27, 2019 Published: March 6, 2019 A

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels Table 1. Annexes A1-A5 from D7566 annex A1 A2

A3 A4

A5

title Fischer−Tropsch Hydroprocessed Synthesized Paraffinic Kerosine (SPK) Synthesized Paraffinic Kerosine from Hydroprocessed Esters and Fatty Acids (HEFA) Synthesized Iso-Paraffins from Hydroprocessed Fermented Sugars (SIP) Synthesized Kerosine with Aromatics Derived by Alkylation of Light Aromatics from Nonpetroleum Sources (SPK/A) Alcohol-to-Jet Synthetic Paraffinic Kerosene (ATJ-SPK)

approved blend ratio (vol %)

production process Paraffins and olefins derived from synthesis gas via the Fischer-Tropsch (FT) process using iron or cobalt catalyst. Synthetic blend components shall be comprised of hydroprocessed synthesized paraffinic kerosine wholly derived from paraffins derived from hydrogenation and deoxygenation of fatty acid esters and free fatty acids. Synthetic blend components shall be comprised of hydroprocessed synthesized iso-paraffins wholly derived from farnesene produced from fermentable sugars. SPK/A synthetic blending component shall be comprised of FT SPK as defined in annex A1 combined with synthesized aromatics from the alkylation of non-petroleum derived light aromatics (primarily benzene). ATJ-SPK synthetic blending components shall be comprised of hydroprocessed synthesized paraffinic kerosene wholly derived from ethanol or isobutanol processed through dehydration, oligomerization, hydrogenation, and fractionation.

50 50

10 50

50

of the correlations between chemical composition and physiochemical properties of jet fuels containing various synthetic blending components is an excellent feedback mechanism for fuel producers. The manufacturers would be equipped with the knowledge of the components necessary and not as needed, which in turn enables fine-tuning of the process. Consecutively, the carbon footprint of the fuel production process can be significantly lowered. Simultaneously, such knowledge is also important for development of analytical methods suitable for identification and determination of these synthetic components in petroleum-based jet fuels. The content of approved synthetic components is limited by the limits mentioned in Table 1, but currently there is no reliable analytical method for their identification and determination. In other words, it is very difficult to measure the content of synthetic components in jet fuel. An added benefit would be to enable a reliable supplierend user relationship due to a different price between jet fuels and blending components. Vrtiška et al.32 focused on the development of a method for determination of HEFA content in HEFA/Jet A blends. The procedure was based on FTIR and partial least-squares regression. The results of this study also showed the possible use of principal component analysis (PCA) to differentiate HEFA from Jet A according to the infrared spectral features. In our previous work,17 three different HEFA fuels produced from different feedstocks (camelina, tallow, and mixed fat) were compared based on their chemical composition and the changes in their properties upon blending with Jet A. In this work, chemical composition and fuel properties (distillation profile, density, viscosity, flash point, freezing point, and net heat of combustion) of additional approved alternative blending components (FT-IPK, SIP, and ATJ) were measured and compared. HEFA produced from camelina was also used in this study for comparison purposes. This work contains detailed chemical analyses of the blending components mentioned above obtained from GC × GC-TOF/MS and FID. Infrared spectroscopy and PCA were utilized in this study as simple procedures to show differences in the chemical composition of the blending components and Jet A and provide an additional tool for the identification of mixtures of blending components and Jet A.

limited to 50 vol %. In principle, any vegetable oil, animal fat, or used cooking oil can be utilized as an HEFA feedstock (e.g., camelina, tallow, reprocessed tallow, mixed fat, etc.).5 The third blending component is synthesized iso-paraffins (SIP) from hydroprocessed fermented sugars which was approved in 2014. SIP is limited in jet fuels to 10 vol %. The fourth component, synthesized paraffinic kerosene with aromatics (FT-SPK/A), was added in 2015, and its content in jet fuels is limited to 50 vol % in the U.S.; however, it can be used as a neat (100%) jet fuel in Europe according to the DEF STAN 91-91.6 The fifth synthetic component, alcohol-to-jet (ATJ) synthetic paraffinic kerosene, was added in 2016 and was limited in jet fuels to 30 vol % until April 2018 with butanol as a feedstock. Later, companies such as LanzaTech and Byogy Renewables have worked on approval for a process with ethanol as a feedstock. These companies, together with Gevo, submitted data to ASTM International. This effort not only resulted in the approval of ethanol as a feedstock but also succeeded in increasing the ATJ maximum blending ratio from 30 to 50 vol %.4 The ATJ process, also called alcohol oligomerization, is typically a three-step process, i.e., alcohol dehydration, oligomerization, and hydrogenation. A wide range of biomass can be used as a feedstock (e.g., corn, unrefined sugars, switchgrass, corn stovers, corn fiber, etc.), and additional details are described in the literature as well as for other nonpetroleum fuel conversion technologies.7 The blending limits of all synthetic components in jet fuel are given in D7566; however, each final blend has to meet all quality requirements specified in the D1655 standard.8 Several studies and reports discuss the chemical composition and/or physiochemical properties of these components, namely, FT-SPK,9−13 HEFA,5,11−17, SIP,9,10,12,18,19 and ATJ;5,9,12,13,20 however, none of them attempt to correlate them. Additionally, a few studies have focused on the prediction of several properties from the chemical composition. One portion of these studies represented jet fuel chemical composition by only three main hydrocarbon classes (nparaffins, aromatics, and branched + cyclic paraffins) measured via NMR and/or HPLC.21−25 Other researchers used near IR26 or GC-MS27,28 together with chemometric modeling or artificial neural networks. Other studies29−31 have used detailed chemical composition obtained from a comprehensive two-dimensional gas chromatography (GC × GC) equipped with time-of-flight mass spectrometry (TOF/MS) and a flame ionization detector (FID). These studies can serve as additional sources for understanding how the properties are affected by chemical composition. A thorough understanding

■

EXPERIMENTAL SECTION

Materials. The petroleum-derived jet fuel Jet A (POSF 9326), Fischer−Tropsch iso-paraffinic kerosene (FT-IPK) produced by Sasol with coal as the feedstock (POSF 7629), hydroprocessed esters and B

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels

Table 3. Chromatographic Conditions for GC × GC-TOF/ MS and GC × GC-FID

fatty acids (HEFA) produced by Honeywell UOP with camelina as the feedstock (POSF 10301), and alcohol-to-jet synthetic paraffinic kerosene (ATJ) produced by Gevo with butanol from microorganisms as the feedstock (POSF 11498) were provided by Wright-Patterson Air Force Base, Dayton, Ohio. Synthesized iso-paraffins from hydroprocessed fermented sugars (SIP) produced by Amyris Inc. with sugar cane as the feedstock were donated by the Aircraft Rescue and Firefighting subdivision of the Federal Aviation Administration, Egg Harbor Township, New Jersey. For this study, mixtures with varying concentrations of fuel blending component (FT-IPK, HEFA, SIP, ATJ) in Jet A were prepared (Table 2). There were also mixtures

GC × GC TOF/MS analytical column carrier gas oven temperature

modulation period offsets secondary oven: 10 °C; modulator: 70 °C temperatures inlet: 280 °C; transfer line: 300 °C solvent n-pentane (+99% pure, Acros Organics), 300 s delay GC × GC-FID description

Table 2. Mixture Compositions and Designations Jet A (vol %)

blending component (vol %)

100 95 90

0 5 10

85 80 70 60 50

15 20 30 40 50

40

60

FT-IPK

HEFA

SIP

FT-IPK HEFA SIP − − SIP 5 FT 10 HEFA 10 SIP 10a − − SIP 15 FT 20 HEFA 20 − FT 30 HEFA 30 − FT 40 HEFA 40 − FT 50a HEFA − 50a FT 60 HEFA 60 −

description primary: Rxi-17Sil MS Restek (60 m × 0.25 mm × 0.25 μm); secondary: Rxi-1 ms Restek (1.4 m × 0.25 mm × 0.25 μm) UHP helium, 1.25 mL/min isothermal 40 °C for 0.2 min, followed by a linear gradient of 1 °C/min to a temperature 200 °C being held isothermally for 5 min 4.0 s with 0.67 s hot pulse time

ATJ ATJ − ATJ 10

analytical column

− ATJ 20 ATJ 30 ATJ 40 ATJ 50a ATJ 60

carrier gas oven temperature modulation period offsets temperatures solvent

a

Maximum allowable concentration for blending with petroleum jet fuels (ASTM D7566).

primary: DB-17MS Agilent (30 m × 0.25 mm × 0.25 μm); secondary: DB-1 MS Agilent (0.8 m × 0.25 mm × 0.25 μm) UHP helium, 1.25 mL/min isothermal 40 °C for 0.2 min, followed by a linear gradient of 1 °C/min to a temperature 160 °C being held isothermally for 5 min 6.5 s with 1.06 s hot pulse time secondary oven: 55 °C; modulator: 15 °C inlet: 280 °C; FID: 300 °C dichloromethane (99.9% pure, Acros Organics), 165 s delay

was employed. IR spectra were measured in the region of 4000−650 cm−1 using the spectral resolution of 2 cm−1. Principal component analysis with singular value decomposition algorithm and mean centering as a pretreatment technique were carried out using an Unscrambler X (CAMO Software AS, Norway) on the recorded spectra. Physical Properties. Table 4 shows the properties measured in this study together with the ASTM methods and instruments utilized.

with content of the synthetic component exceeding the maximum limit required by ATSM D7566 in order to investigate in detail the effect it had on various properties. GC × GC. For qualitative analysis of the samples, a twodimensional gas chromatography with time-of-flight and mass spectrometry detector (GC × GC-TOF/MS) LECO Pegasus GCHRT 4D High Resolution TOF/MS was used. Chromatographic conditions for GC × GC-TOF/MS are shown in Table 3. The ion source temperature was set to 250 °C, and the electron energy was 70 eV. Data were collected over an m/z range of 45−550 and were processed and analyzed via LECO Visual Basic Scripting (VBS) software, ChromaTOF version 1.90. Identification of the compounds was achieved by matching the measured mass spectra (match factor threshold > 800) with Wiley (2011) and NIST (2011) mass spectral databases. For quantitative analysis of the samples, a two-dimensional gas chromatography with flame ionization detector (GC × GC-FID) Agilent 7890B was used. Chromatographic conditions for GC × GCFID are shown in Table 3. Data were collected and processed using the ChromaTOF software version 4.71 optimized for GC × GC-FID with a signal-to-noise ratio of 75. Both systems were equipped with a non-moving quad-jet dual stage thermal modulator and liquid nitrogen for modulation. For both instruments, 10 μL of sample was diluted in 1 mL of solvent, and 0.5 μL of the sample solution was injected with a 20:1 split ratio. GC × GC-TOF/MS data enabled us to develop a detailed chemical classification on the GC × GC-FID ChromaTOF. The classification included carbon numbers between C7 and C20 for all main hydrocarbon classes, such as n-paraffins, isoparaffins, monocycloparaffins, di- and tricycloparaffins, alkylbenzenes, cycloaromatics (indans, tetralins, etc.), and alkylnaphthalenes. The weight percent of each group (all compounds with the same carbon number for the same hydrocarbon class) were obtained by dividing the peak area of the group by the total peak area of the sample. Detailed description of the classification with pictorial representation can be found in previous papers.17,30,31 Infrared Spectroscopy. All infrared spectra (IR) samples were recorded using an IRAffinity-1 spectrometer coupled with LabSolution IR software (Shimadzu, Japan). The transmission sampling technique utilizing a ZnSe sample cell with path length of 0.1053 mm

Table 4. Property Measurements ASTM

instrument

simulated distillation (SIM DIST) density

properties

D2997

viscosity

D7042

freezing point flash point hydrogen content nitrogen content

D2386 D56 D3701 D4629

sulfur content

D5453

gross heat of combustion aromatic content (vol %)

D4809

Trace GC Ultra Gas Chromatograph (Thermo Scientific) Stabinger Viscometer SVM 3001 (Anton Paar) Stabinger Viscometer SVM 3001 (Anton Paar) K29700 (Koehler Instrument) Tag 4 Flash Point Tester (Anton Paar) high-resolution NMR31 Xplorer-NS (Trace Element Instruments) Xplorer-NS (Trace Element Instruments) 6200 Isoperibol Calorimeter (Parr Instrument Co.) LC-10 CE (Shimadzu)

D4052

D6379

The experimental investigations were conducted at the wellestablished Fuel Laboratory of Renewable Energy at Purdue University.

■

RESULTS AND DISCUSSION Composition of Neat Blending Components. Figure 1 shows the GC × GC-TOF/MS chromatogram of Jet A with all significant hydrocarbon classes, which were further analyzed C

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels

content of C17 isoparaffins (21.26 wt %). The high amount of iso-C17 hydrocarbons compared to other isoparaffins can be explained by the process itself and by the HEFA feedstock. Camelina consists predominantly of triglycerides containing linolenic, linoleic, and oleic acids, all with 18 carbons in the molecule. In HEFA production process, hydrodecarbonylation and hydrodecarboxylation dominated over hydrodeoxygenation, yielding mainly hydrocarbons with a carbon number one less than that of fatty acids bonded in molecules of the feedstock. On the other hand, isoparaffins present in FT-IPK were in the range of C8 to C15, and their distribution was normal with a maximum in iso-C12. HEFA and FT-IPK both contained a small amount of monocycloparaffins in the range of C8 to C12, and their content did not exceed 3.0 wt %. There were no detectable dicycloparaffins nor tricycloparaffins in either of the samples. The total content of aromatics was extremely low in FT-IPK and HEFA (0.30 and 0.03 wt % respectively). HEFA contained only alkylbenzenes (C9−C10) and no cycloaromatics or naphthalenes, while FT-IPK contained alkylbenzenes (C8−C11), cycloaromatics (C11− C13), and alkylnaphthalenes (C11). Further comparison of the SIP and ATJ provided additional differences as well. n-Paraffins were not detected in either sample. SIP isoparaffins were in the range of C14 to C16 with the following concentrations: 0.05 wt % iso-C14, 99.40 wt % iso-C15 (farnesane), and 0.03 wt % iso-C16. ATJ isoparaffins were distributed in the range of C8 to C23, where iso-C12 and iso-C16 content was 82.27 and 11.71 wt %, respectively. Monocycloparaffins observed in SIP and ATJ were C14 and C9−C10, respectively. Dicycloparaffins, tricycloparaffins, cycloaromatics, and alkylnaphthalenes were not detected in either sample. The trace amount of aromatics in SIP came solely from C15 alkylbenzenes (0.06 wt %). ATJ did not contain any alkylbenzenes. Sulfur, Nitrogen, and Hydrogen Content. Table 6 displays the sulfur, nitrogen, and hydrogen contents of neat blending components. As expected, bio-based blending components (HEFA, SIP, and ATJ) contained only a negligible amount of sulfur, while FT-IPK (coal feedstock) contained an order higher amount of sulfur than that found in bio-based components. Nitrogen content was slightly higher for all blending components when compared to Jet A. It was also obvious that all synthetic blending components had significantly higher hydrogen content than Jet A fuel. This was caused primarily by the absence of aromatics, which have a high carbon/hydrogen ratio. Sulfur and hydrogen contents were used for net heat of combustion calculations. The values of the sulfur and hydrogen content in fuel mixtures were calculated utilizing the constituent component mass fractions and pertinent individual sulfur and hydrogen contents. Infrared Spectroscopy. There are basically no methods for detecting and determining alternative blending components in petroleum-based Jet A. The method in ref 33, which measures the content of radiocarbon 14C, can only measure the content of bio-based alternative blending components; however, it cannot detect which blending component was used (e.g., HEFA vs ATJ). Therefore, infrared spectroscopy was utilized in order to investigate if such a relatively simple analytical method together with proper chemometric processing can predict which type of alternative blending component was used in the mixture with Jet A. PCA is one of the most fundamental chemometric techniques used for the processing of multivariate data. The aim of the PCA is reduction of the

Figure 1. GC × GC chromatogram of Jet A with section identifications: (1) n- and isoparaffins, (2) monocycloparaffins, (3) di- and tricycloparaffins, (4) monoaromatics, (5) cycloaromatics, and (6) diaromatics.

quantitatively using GC × GC-FID. The hydrocarbon composition of Jet A and fuel blending components obtained from GC × GC-FID is shown in Table 5. Further information on detailed composition of this Jet A sample was discussed previously.17 Figure 2 shows the GC × GC-TOF/MS chromatograms of the synthetic blending components mentioned above. Details on their chemical compositions are provided in further sections. FT-IPK was mostly composed of isoparaffins. HEFA was composed predominantly of n-paraffins and isoparaffins. SIP and ATJ predominantly contained isoparaffins, while ATJ contained isoparaffins up to C23. SIP was composed of 99.40 wt % of farnesane (2,6,10-trimethyldodecane) having 15 carbon atoms in its molecule. Farnesane is the only visible peak with tr′ 4433 s and tr′′ 3.85 s on Figure 2c. The most abundant constituents of ATJ were two compounds, i.e., 2,2,4,6,6-pentamethylheptane (tr′ 1332 s and tr′′ 3.55 s) in concentration of 66.50 wt % and 2,2,4,4,6,8,8-heptamethylnonane (tr′ 3913 s and tr′′ 0.17 s) in concentration of 8.58 wt %. Two additional C12 isoparaffins were detected in significant amounts, i.e., 4.63 wt % (tr′ 1712 s and tr′′ 3.65 s) and 4.48 wt % (tr′ 3729 s and tr′′ 7.2 s). These compounds are clearly visible in Figure 2d. Aromatic content is limited for all blending components (ASTM D7566, annexes A1−A5) by the maximum value of 0.50 wt % and was met by all blending components. Further comparison of the HEFA and FT-IPK provided additional differences. HEFA n-paraffin content was 8.53 wt % and was distributed in the carbon atom range of n-C8 to n-C17. On the other hand, FT-IPK contained a very low amount (0.39 wt %) of n-paraffins in the range of n-C10 to n-C16. HEFA isoparaffins were in the range of C8 to C18, with the highest D

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels Table 5. Hydrocarbon Type Composition (wt %) of Jet A, FT-IPK, HEFA, SIP, and ATJ hydrocarbon class n-paraffins C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 total n-paraffins isoparaffins C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 C18 C19 C20 C21 C22 C23 total isoparaffins monocycloparaffins C7 C8 C9 C10 C11 C12 C13 C14 C15 total monocycloparaffins

Jet A 0.83 5.05 4.96 3.36 2.37 1.90 1.27 0.76 0.36 0.10 0.02 20.97

FTIPK 0.00 0.00 0.10 0.00 0.13 0.08 0.04 0.03 0.01 0.00 0.00 0.39

HEFA 1.56 2.15 1.38 0.96 0.83 0.65 0.25 0.51 0.13 0.10 0.00 8.53

SIP 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

ATJ 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.28 4.97 6.94 5.36 3.69 3.51 2.63 1.97 0.94 0.23 0.06 0.00 0.00 0.00 0.00 0.00 30.58

0.52 7.93 19.39 23.50 27.70 11.73 5.10 1.07 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 96.94

1.48 11.18 11.35 9.87 8.47 8.17 6.29 5.59 2.35 21.26 3.66 0.00 0.00 0.00 0.00 0.00 89.68

0.00 0.00 0.00 0.00 0.00 0.00 0.05 99.40 0.03 0.00 0.00 0.00 0.00 0.00 0.00 0.00 99.49

0.42 0.25 0.00 0.94 82.27 0.61 0.15 1.30 11.71 1.61 0.00 0.04 0.00 0.03 0.58 0.01 99.93

0.22 3.74 4.47 4.10 2.85 2.25 1.67 0.69 0.12 20.12

0.00 0.06 0.39 0.76 0.83 0.33 0.00 0.00 0.00 2.37

0.00 0.81 0.51 0.29 0.08 0.03 0.00 0.00 0.00 1.73

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.42 0.00 0.42

0.00 0.00 0.01 0.00 0.06 0.00 0.00 0.00 0.00 0.07

hydrocarbon class

Jet A

FTIPK

HEFA

SIP

ATJ

di- and tricycloparaffins C8 C9 C10 C11 C12 C13 C14 total di- and tricycloparaffins total cycloparaffins

0.23 0.78 1.01 1.07 0.80 0.27 0.14 4.30

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

24.41

2.37

1.73

0.42

0.07

alkylbenzenes C8 C9 C10 C11 C12 C13 C14 C15 C16 C17 total alkylbenzenes

0.07 1.79 4.86 3.27 2.15 1.72 1.04 0.35 0.19 0.02 15.46

0.01 0.07 0.08 0.04 0.00 0.00 0.00 0.00 0.00 0.00 0.20

0.00 0.01 0.02 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.03

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.06 0.00 0.00 0.06

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

cycloaromatics C9 C10 C11 C12 C13 C14 C15 total cycloaromatics

0.14 0.78 1.73 2.24 1.26 0.73 0.01 6.89

0.00 0.00 0.01 0.05 0.01 0.00 0.00 0.07

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.11 0.41 0.64 0.43 0.09 0.01 1.69

0.00 0.02 0.00 0.00 0.00 0.00 0.02

0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00

0.00 0.00 0.00 0.00 0.00 0.00 0.00

24.05

0.30

0.03

0.06

0.00

alkylnaphthalenes C10 C11 C12 C13 C14 C15 total alkylnaphthalenes total aromatics

processing. The selected spectral region of Jet A, FT-IPK, HEFA, SIP, and ATJ is shown in Figure 3. The selected region contained sufficient spectral information for the comparison of the particular jet fuel components36 and contained bands which can be predominantly attributed to the rocking vibrations of methyl and methylene groups, skeletal vibrations of various grouping of carbon atoms, and in-plane and out-ofplane deformations vibrations of bands present in the aromatic structures. The aromatic bands (805, 767, 741, and 698 cm−1) can be observed primarily in the spectrum of Jet A. The absorption intensity of these bands in the spectra of the blending components with no or low aromatic content is negligible. The spectrum of ATJ is composed of four dominant

original variables while maintaining as much important information present in the original data as possible. The original variables are transformed (using linear combinations) to usually much lower number of new variables called principal components (PC). The major output of PCA are two matrices: scores (each sample has its own set of score values) and loadings (each original variable has its own set of loadings values). Projection of the scores and loadings values to the 2D plots offers interesting insight into the multivariate data. A more detailed description of PCA can be found elsewhere.34,35 Infrared spectra of the samples were measured in the region of 4000−650 cm−1; however, only a narrower portion (1320− 680 cm−1) of the recorded spectra was utilized for further E

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels

Figure 2. Comparison of GC × GC-TOF/MS chromatograms of synthetic blending components: (a) FT-IPK, (b) HEFA, (c) SIP, and (d) ATJ.

attributed to the stretching vibration of C−C bond from the >C(CH3)2 group (1170 cm−1) and the rocking vibration of the same group (1151 cm−1). The bands that can be attributed to the CH3 rocking vibrations from groups (R)3−C−CH3 and (R)3−C−CH2−CH3 can be found at 968 and 919 cm−1, respectively. The two remaining dominant bands (770 and 735 cm−1) can be attributed to the rocking vibrations of the groups −CH2− and −(CH2)3−, respectively. The spectrum of HEFA is mainly composed of the bands mentioned above. The additional band observed at 723 cm−1 can be attributed to the rocking vibration of −(CH2)n− for n > 3 and can be associated with long unbranched hydrocarbon chains. This band was also observed in Jet A spectrum. The recorded infrared spectra of Jet A, neat blending components, and their mixtures were utilized as input data for the PCA. Although the first three principal components (PC1 to PC3) were able to capture 98% of original data variability, it was beneficial to use PC4 as well. The plots of PC1 vs PC2,

Table 6. Sulfur (mg/kg), Nitrogen (mg/kg), and Hydrogen (wt %) Contents in Jet A, FT-IPK, HEFA, SIP, and ATJ sulfur nitrogen hydrogen

Jet A

FT-IPK

HEFA

SIP

ATJ

573 6 13.8

13 9 15.12

2 8 15.45

110 −b −b − − ATJ 40

44.0 43.8 44.5 44.7 45.1

46.0 45.2 45.6 46.3 46.5

FT 60

FT-IPK

Jet A 43.0 − − − − ATJ 50

ATJ 60

ATJ

46.0 47.6 48.8 48.3 48.1

46.0 50.1 50.6 50.4 49.5

48.5 55.4 52.6 − −

a

Predicted data from SIM DIST. bNot calculated due to the D56 method limitations.

several researchers.17,23,40 In this study, SIP, ATJ, and FT-IPK freezing point values were below the detection limit (less than −70 °C) of the D2386 apparatus due to the fact that SIP and ATJ did not contain any n-paraffins and FT-IPK contained only a negligible amount (0.39 wt %). On the other hand, HEFA contained a significant amount of n-paraffins (8.53 wt %), which caused the freezing point value to be −55 °C. The freezing point values of the mixtures were observed to fall in between the freezing points of their blending components (Table 9). The repeatability of freezing point values in this study was 0.5 °C; the repeatability of the D2386 method is reported as 1.5 °C, which could be the reason why several mixtures had the same freezing point. The maximum freezing point values permitted by ASTM are −40 and −47 °C for Jet A and Jet A-1, respectively. Therefore, the addition of these blending components to Jet A/A-1 does not increase this value. However, it was shown in previous paper17 that the final freezing point can be increased if the batch of HEFA used for mixing has a freezing point higher than that of Jet A. As already discussed in a previous paper,17 none of the Cookson equations for freezing point predicted accurate results for HEFA/Jet A mixtures. Similarly, none of the Cookson

acted as a surrogate mixture for HEFA (composed of n-, iso-, and monocycloparaffins). In spite of the fact that both SIP and ATJ samples were composed mostly of isoparaffins, there was a significant difference between their viscosity values. The high viscosity value of SIP stemmed from the viscosity of its most prominent compound, i.e., farnesane (99.4 wt %). The carbon number of the most abundant component of ATJ (66.50 wt % of 2,2,4,6,6-pentamethylheptane) was 3 times lower than that of farnesane and the level of branching was higher, both of which resulted in a lower ATJ viscosity value. As for FT-IPK and HEFA samples, their isoparaffins content was in close proximity. HEFA contained more n-paraffins than FT-IPK. nParaffins have higher viscosity values than those of isoparaffins for the same carbon number. Moreover, FT-IPK contained isoparaffins with a lower carbon number than HEFA. Freezing Point. The freezing point is very dependent on the molecular structure.17 n-Paraffins exhibit the highest freezing point among all hydrocarbon groups,39 and the freezing point increases with increasing carbon number. Therefore, the freezing point is driven by the heaviest nparaffins in the fuel. This observation was also confirmed by L

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels

Table 11. Net Heat of Combustion (MJ/kg) of Jet A, FT-IPK, HEFA, SIP, ATJ, and Their Mixtures with Jet A Determined Using ASTM D4809 and Calculated from eq 3 and ASTM D3338 FT 10 D4809 eq 3 D3338 D4809 eq 3 D3338

43.11 43.19 43.19 HEFA 10

FT 20

FT 30

FT 40

FT 50

FT 60

43.19 43.28 43.26 HEFA 20

43.32 43.37 43.34 HEFA 30

43.54 43.45 43.42 HEFA 40

43.57 43.54 43.51 HEFA 50

43.67 43.63 43.60 HEFA 60

44.00 − 43.96 HEFA

43.35 43.51 43.53

43.55 43.61 43.63

43.64 43.72 43.73

44.15 − 44.13

43.16 43.21 43.24 SIP 5

43.27 43.31 43.34 SIP 10

43.35 43.41 43.43 SIP 15

D4809 eq 3 D3338

43.13 43.15 43.15 ATJ 10

43.13 43.20 43.20 ATJ 20

43.22 43.24 43.24 ATJ 30

D4809 eq 3 D3338

43.24 43.20 43.19

43.34 43.29 43.27

SIP

Jet A

44.01 − 44.08 ATJ 40

43.34 43.38 43.36

FT-IPK

43.11 − 43.13

43.42 43.48 43.44

ATJ 50

ATJ 60

ATJ

43.53 43.57 43.54

43.63 43.67 43.64

44.06 − 44.00

mixtures containing other blending components. Results from eq 2 and the original equation from ASTM method D7215 are shown in Table 10. Additionally, both equations were used for prediction of the flash point from SIM DIST data calculated from the data of neat components (discussed in the Distillation Profile section). Most of the predicted values from both equations were within the repeatability of the ASTM D56 method (1.2 °C) except for three samples (SIP 5, SIP 10, and ATJ). The values highlighted in Table 10 are those where the D7215 equation predicted better results than eq 2. Net Heat of Combustion. Net heat of combustion (NHC) values of all neat blending component samples were higher than the minimum limit of 42.8 MJ/kg defined by ASTM D1655. NHC decreases in the order of paraffins > cycloparaffins > aromatics. NHC of isoparaffins is in most cases slightly lower than that of n-paraffins for the same carbon number.29,39 When the neat blending components (Table 10) were compared, NHC increased in the following order: FTIPK < SIP < ATJ < HEFA. All samples exhibited higher NHC values than that of Jet A; therefore, the mixing did not negatively influence the final NHC value. The same approach that was utilized for density was used for NHC in order to discover how the NHC was affected by the chemical composition. This approach enables us to compare the contribution to the total NHC of each carbon number and each hydrocarbon class. The net heat of combustion calculation from GC × GC-FID chemical compositions was previously introduced in the literature29 and was further detailed elsewhere.17 NHC data calculated from GC × GCFID can be found in the Supporting Information (Table S3). Additionally, NHC values of each mixture can be simply calculated from the Jet A and blending component NHC values, as displayed in eq 3.

equations predicted the accurate results for the other blending components utilized in this study. The data calculated from the Cookson equations can be found in the Supporting Information. Flash Point. The flash point of the neat blending components increased in the following order: FT-IPK < HEFA < ATJ < SIP. The SIP flash point could not be measured as the D56 method range is only up to 110 °C. This observation was supported also by the IBP values of these samples. Flash point values of pure hydrocarbons increase with increasing carbon number39 and also as expected increase with increasing boiling point. Based on the findings in our previous work,17 isoparaffins had the lowest flash point among all of the saturated hydrocarbons with the same carbon number. FT-IPK and HEFA flash point values were very similar (the difference was only 1 °C); however, the FT-IPK flash point was lower than that of HEFA even though the content of isoparaffins with low carbon numbers (C8 and C9) was higher in HEFA. FT-IPK contained, in addition to HEFA, 0.30 wt % of aromatics (up to C13). These aromatics have a low flash point and potentially could lower the final flash point. Similar to the freezing point, the flash point values of all the mixtures prepared fell between the values of the neat blend components (e.g., Jet A flash point was 43.0 °C, ATJ flash point was 48.5 °C; therefore, all Jet A/ATJ mixtures flash point values were between 43.0 and 48.5 °C). Due to this, the components with flash point values lower (FT-IPK and HEFA) than that of Jet A decreased the final flash point of each mixture. On the contrary, the components with flash point values higher (SIP and ATJ) than that of Jet A increased the final flash point of each mixture. The repeatability of the ASTM D56 method is 1.2 °C, which could explain the reason of several mixtures with the same flash point value. In our previous paper,17 a new equation for calculation of HEFA/Jet A mixtures flash point was developed:

NHCm =

∑ wi NHCi i

CFPD56 = − 39.244 + 0.246TIBP − 0.058T5% + 0.428T10% (2)

(3)

where NHCm is the net heat of combustion of the mixture, wi the weight fraction of the neat blend component, and NHCi the net heat of combustion of the neat blend component. Another method that can be used for NHC calculations for jet fuels utilizes distillation data, aromatic content (vol %), and density is the ASTM method D3338. Although, this method

In this equation, CFP is the calculated flash point, TIBP the initial boiling point temperature, and T5% and T10% the temperatures at which 5 and 10 wt % of the sample were recovered, respectively. TIBT, T5%, and T10% are data from simulated distillation. Here, this equation was tested for M

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Energy & Fuels

■

was not originally designed for alternative aviation fuels, results from our previous work17 showed that this method was very suitable for HEFA/Jet A mixtures. Here, eq 3 and the D3338 method were also tested for other alternative blending components. The results obtained in this study were compared to experimental data obtained via ASTM D4809. The difference was below the reproducibility and the repeatability of ASTM D4809. Therefore, further improvement of the equation from ASTM D3338 was not necessary. Comparison of all results obtained from ASTM D4809, D3338, and eq 3 are shown in Table 11.

■

Article

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.energyfuels.9b00105. Distillation profiles of Jet A, FT-IPK, HEFA, SIP, and ATJ estimated from SIM DIST data; difference between predicted and measured SIM DIST values for HEFA mixtures; difference between predicted and measured SIM DIST values for SIP mixtures; difference between predicted and measured SIM DIST values for ATJ mixtures; difference between predicted and measured SIM DIST values for HEFA produced from tallow; difference between predicted and measured SIM DIST values for HEFA produced from mix fat; comparison of GC × GC-TOF/MS chromatograms of fuel blending component and Jet A mixtures; hydrocarbon type composition (wt %) for ten selected samples; freezing point of Jet A, FT-IPK, HEFA, SIP, ATJ, and their mixtures (°C) calculated from Cookson equations; and net heat of combustion contribution (MJ/kg) for every carbon number from each hydrocarbon class (PDF)

SUMMARY AND CONCLUSION

In this study, detailed compositions of Jet A and four alternative blending components, i.e., FT-IPK, HEFA (from camelina), SIP, and ATJ, were achieved using comprehensive two-dimensional gas chromatography with electron ionization high-resolution time-of-flight and mass spectrometry and flame ionization detectors. Each blending component had a specific chemical composition and an individual number of compounds. Infrared spectroscopy and principal components analysis were utilized as supplementary techniques in order to clearly demonstrate the differences among the blending components and Jet A. Mixtures of Jet A and each blending component were prepared in varying ratios. Main physiochemical properties of all blending components and all mixtures were determined. A method for calculating the simulated distillation data of the mixtures was introduced and validated. Density and net heat of combustion of the mixtures were additive and were simply calculated from Jet A and HEFA neat values. Viscosity was not additive. The correlation between the viscosity and increasing concentrations of the blending components in Jet A displayed a second-degree polynomial trend. Slight inconsistency in viscosity was observed for HEFA and ATJ mixtures. The freezing point of blending components was lower than that of Jet A; therefore, the final freezing point was not negatively affected. Zero or negligible amount of n-paraffins in FT-IPK, ATJ, and SIP prevented the detection of the freezing point via ASTM D2386. The freezing point of all mixtures fell between freezing points of individual blend components and no inconsistencies were observed. Similarly, the flash point of all mixtures fell between flash points of individual blend components. The components with a lower flash point value (FT-IPK and HEFA) than that of Jet A decreased the final flash point of each mixture. On the contrary, the components with higher flash point values (SIP and ATJ) than that of Jet A increased the final flash point of each mixture. An equation for flash point calculations, which was introduced in our previous paper, was further validated in this study. Calculated simulated distillation data yielded similar flash point values from this equation when compared to flash point values obtained using experimentally measured simulated distillation data. The net heat of combustion (NHC) of each blending component was higher than that of Jet A; therefore, the mixing did not negatively influence the final NHC value. The ASTM D3338 for the calculation of NHC was validated, and it was shown that this method produced very similar results to those experimentally obtained from the ASTM D4809.

■

AUTHOR INFORMATION

Corresponding Author

*E-mail: [email protected]. Tel.: 765-494-7486. Fax: 765494-6219. ORCID

Petr Vozka: 0000-0002-8984-9398 Gozdem Kilaz: 0000-0002-0302-6527 Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS This work was supported by the U.S. Navy, Office of Naval Research (N000141613109 awarded by the Naval Enterprise Partnership Teaming with Universities for National Excellence (NEPTUNE) Center for Power and Energy Research). This work was also supported by the National Program of Sustainability (NPU I LO1613, MSMT-43760/2015). The authors thank Dr. James T. Edwards (USAF) for providing the fuel samples and for his contribution to the Introduction section.

■

REFERENCES

(1) ASTM D4054-17, Standard Practice for Evaluation of New Aviation Turbine Fuels and Fuel Additives; ASTM International: West Conshohocken, PA, 2017; DOI: 10.1520/D4054-17. (2) Edwards, J. T. Liquid fuels and propellants for aerospace propulsion: 1903−2003. J. Propul. Power 2003, 19 (6), 1089−1107. (3) Hemighaus, G.; Rumizen, M. Discussion on Uses of the Specification for Turbine Fuels Using Synthesized Hydrocarbons (ASTM D7566). Fuels Specifications: What They Are, Why We Have Them, and How They Are Used, MNL69-EB 2016, 83−88. (4) ASTM D7566-18a, Standard Specification for Aviation Turbine Fuel Containing Synthesized Hydrocarbons; ASTM International: West Conshohocken, PA, 2018; DOI: 10.1520/D7566-18A. (5) Edwards, J. T.; Shafer, L. M.; Klein, J. K. Interim Report (AFRLRQ-WP-TR-2013-0108). U.S. Air Force Hydroprocessed Renewable Jet (HRJ) Fuel Research; Air Force Research Laboratory, Aerospace Systems Directorate, Wright-Patterson Air Force Base: Dayton, OH, 2012; https://apps.dtic.mil/dtic/tr/fulltext/u2/a579552.pdf. N

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX

Article

Energy & Fuels (6) Defence Standard 91-91. Turbine Fuel, Kerosine Type, Jet A-1; NATO Code: F-35; Joint Service Designation: AVTUR; MODUKBritish Defense Standards (MODUK): 2018. (7) Wang, W. C.; Tao, L. Bio-jet fuel conversion technologies. Renewable Sustainable Energy Rev. 2016, 53, 801−822. (8) ASTM D1655-18b Standard Specification for Aviation Turbine Fuels; ASTM International: West Conshohocken, PA, 2018; DOI: 10.1520/D1655-18B. (9) Striebich, R. C.; Shafer, L. M.; Adams, R. K.; West, Z. J.; DeWitt, M. J.; Zabarnick, S. Hydrocarbon Group-Type Analysis of PetroleumDerived and Synthetic Fuels Using Two-Dimensional Gas Chromatography. Energy Fuels 2014, 28 (9), 5696−5706. (10) Moses, C. A. Addendum: Further Analysis of Hydrocarbons and Trace Materials To Support Dxxxx (AV-2-04a). Comparative evaluation of semi-synthetic jet fuels; Coordinating Research Council: 2009. (11) Webster, R. L.; Rawson, P. M.; Kulsing, C.; Evans, D. J.; Marriott, P. J. Investigation of the Thermal Oxidation of Conventional and Alternate Aviation Fuels with Comprehensive TwoDimensional Gas Chromatography Accurate Mass Quadrupole Time-of-Flight Mass Spectrometry. Energy Fuels 2017, 31 (5), 4886−4894. (12) Zschocke, A.; Scheuermann, S.; Ortner, J. Interim Report (ENER/C2/2012/420-1). High Biofuel Blends in Aviation (HBBA); Deutsche Lufthansa AG and Wehrwissenschaftliches Institut für Werk und Betriebsstoffe: 2017; Vol. 2, 1−420. (13) Cox, D.; Davis, T. Certification Report: Army Aviation Alternative Fuels Certification Program (RDMR-AE-16-02); U.S. Army Research, Development, and Engineering Command Redstone Arsenal: United States, 2016; https://apps.dtic.mil/dtic/tr/fulltext/u2/1015528.pdf. (14) Pires, A. P. P.; Han, Y.; Kramlich, J.; Garcia-Perez, M. Chemical Composition and Fuel Properties of Alternative Jet Fuels. BioResources 2018, 13 (2), 2632−2657. (15) Luning Prak, D. J.; Brown, E. K.; Trulove, P. C. Density, Viscosity, Speed of Sound, and Bulk Modulus of Methyl Alkanes, Dimethyl Alkanes, and Hydrotreated Renewable Fuels. J. Chem. Eng. Data 2013, 58 (7), 2065−2075. (16) Gawron, B.; Białecki, T. Impact of a Jet A-1/HEFA Blend on the Performance and Emission Characteristics of a Miniature Turbojet Engine. Int. J. Environ. Sci. Technol. 2018, 15 (7), 1501− 1508. (17) Vozka, P.; Simacek, P.; Kilaz, G. Impact of HEFA Feedstocks on Fuel Composition and Properties in Blends with Jet A. Energy Fuels 2018, 32 (11), 11595−11606. (18) Weisser, K. L.; Turgeon, R. T.; Kamin, R.; Mearns, D. 90/10 JP5/Synthesized ISO-Paraffin Specification and Fit-for-Purpose Test Results (ADA618841); Naval Air Systems Command, Patuxent River, MD Fuels and Lubricants Div.: 2014; https://apps.dtic.mil/dtic/tr/ fulltext/u2/a618841.pdf. (19) Dickerson, T.; Buffin, J.; Kamin, R.; Mearns, D. Impact of 50% Synthesized Iso-Paraffins (SIP) on F-76 Fuel Coalescence (ADA618856); Naval Air Systems Command, Patuxent River, MD Fuels and Lubricants Div.: 2013; https://apps.dtic.mil/dtic/tr/fulltext/u2/ a618856.pdf. (20) Luning Prak, D. J.; Jones, M. H.; Trulove, P.; McDaniel, A. M.; Dickerson, T.; Cowart, J. S. Physical and Chemical Analysis of Alcohol-to-Jet (ATJ) Fuel and Development of Surrogate Fuel Mixtures. Energy Fuels 2015, 29 (6), 3760−3769. (21) Cookson, D. J.; Iliopoulos, P.; Smith, B. E. CompositionProperty Relations for Jet and Diesel Fuels of Variable Boiling Range. Fuel 1995, 74 (1), 70−78. (22) Cookson, D. J.; Latten, J. L.; Shaw, I. M.; Smith, B. E. PropertyComposition Relationships for Diesel and Kerosene Fuels. Fuel 1985, 64 (4), 509−519. (23) Cookson, D. J.; Lloyd, C. P.; Smith, B. E. Investigation of the Chemical Basis of Kerosene (Jet Fuel) Specification Properties. Energy Fuels 1987, 1 (5), 438−447.

(24) Cookson, D. J.; Smith, B. E. Calculation of jet and diesel fuel properties using carbon-13 NMR spectroscopy. Energy Fuels 1990, 4 (2), 152−156. (25) Cookson, D. J.; Smith, B. E. Observed and Predicted Properties of Jet and Diesel Fuels Formulated from Coal Lliquefaction and Fischer−Tropsch Feedstocks. Energy Fuels 1992, 6 (5), 581−585. (26) Morris, R. E.; Hammond, M. H.; Cramer, J. A.; Johnson, K. J.; Giordano, B. C.; Kramer, K. E.; Rose-Pehrsson, S. L. Rapid Fuel Quality Surveillance Through Chemometric Modeling of NearInfrared Spectra. Energy Fuels 2009, 23 (3), 1610−1618. (27) Liu, G.; Wang, L.; Qu, H.; Shen, H.; Zhang, X.; Zhang, S.; Mi, Z. Artificial Neural Network Approaches on Composition−Property Relationships of Jet Fuels Based on GC−MS. Fuel 2007, 86 (16), 2551−2559. (28) Cramer, J. A.; Hammond, M. H.; Myers, K. M.; Loegel, T. N.; Morris, R. E. Novel Data Abstraction Strategy Utilizing Gas Chromatography−Mass Spectrometry Data for Fuel Property Modeling. Energy Fuels 2014, 28 (3), 1781−1791. (29) Shi, X.; Li, H.; Song, Z.; Zhang, X.; Liu, G. Quantitative Composition-Property Relationship of Aviation Hydrocarbon Fuel Based on Comprehensive Two-Dimensional Gas Chromatography with Mass Spectrometry and Flame Ionization Detector. Fuel 2017, 200, 395−406. (30) Vozka, P.; Mo, H.; Š imácě k, P.; Kilaz, G. Middle Distillates Hydrogen Content via GC × GC-FID. Talanta 2018, 186, 140−146. (31) Vozka, P.; Modereger, B. A.; Park, A. C.; Zhang, W. T. J.; Trice, R. W.; Kenttämaa, H. I.; Kilaz, G. Jet Fuel Density via GC × GC-FID. Fuel 2019, 235, 1052−1060. (32) Vrtiška, D.; Vozka, P.; Váchová, V.; Š imácě k, P.; Kilaz, G. Prediction of HEFA content in jet fuel using FTIR and chemometric methods. Fuel 2019, 236, 1458−1464. (33) ASTM D6866-18, Standard Test Methods for Determining the Biobased Content of Solid, Liquid, and Gaseous Samples Using Radiocarbon Analysis; ASTM International: West Conshohocken, PA, 2018; DOI: 10.1520/D6866-18 (34) Jolliffe, I.T. Principal Component Analysis and Factor Analysis. Principal Component Analysis 1986, 115−128. (35) Naes, T.; Isakon, T.; Feam, T.; Davies, T. A user friendly guide to multivariate calibration and classification; NIR Publications: Chichester, England, 2002. (36) Socrates, G. Tables and Charts. Infrared and Raman Characteristic Group Frequencies; Wiley: Chichester, England, 2001. (37) ASTM D2887-18, Standard Test Method for Boiling Range Distribution of Petroleum Fractions by Gas Chromatography; ASTM International: West Conshohocken, PA, 2018; DOI: 10.1520/D288718 (38) Š imácě k, P.; Kubička, D.; Pospíšil, M.; Rubás,̌ V.; Hora, L.; Š ebor, G. Fischer−Tropsch product as a co-feed for refinery hydrocracking unit. Fuel 2013, 105, 432−439. (39) Braun-Unkhoff, M.; Kathrotia, T.; Rauch, B.; Riedel, U. About the Interaction Between Composition and Performance of Alternative Jet Fuels. CEAS Aeronautical Journal 2016, 7 (1), 83−94. (40) Solash, J.; Hazlett, R. N.; Hall, J. M.; Nowack, C. J. Relation Between Fuel Properties and Chemical Composition. 1. Jet Fuels from Coal, Oil Shale and Tar Sands. Fuel 1978, 57 (9), 521−528.

O

DOI: 10.1021/acs.energyfuels.9b00105 Energy Fuels XXXX, XXX, XXX−XXX