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A comprehensive study on the composition of aerosol emissions from a
ship-diesel engine operated with diesel fuel or heavy fuel oil
Thorsten Streibel1,2*, Jürgen Schnelle-Kreis2, Hendryk Czech1, Horst Harndorf3, Gert Jakobi2, Jorma
Jokiniemi4, Erwin Karg2, Jutta Lintelmann2, Georg Matuschek2, Bernhard Michalke, Laarnie Müller2,
Jürgen Orasche2, Johannes Passig1, Christian Radischat1, Rom Rabe3, Ahmed Reda2, Christopher
Rüger1, Theo Schwemer1, Olli Sippula4, Benjamin Stengel3, Martin Sklorz1, Tiina Torvela4, Benedikt
Weggler2, Ralf Zimmermann1,2
1 Joint Mass Spectrometry Centre, Chair of Analytical Chemistry, Institute of Chemistry, University Rostock, Germany
2 Joint Mass Spectrometry Centre, CMA-Comprehensive Molecular Analytics, Helmholtz ZentrumMünchen, Neuherberg, Germany
3 Chair of Piston Machines and Internal Combustion Engines, University Rostock, Germany4 Fine Particle and Aerosol Technology Laboratory and Inhalation Toxicology Laboratory,
Department of Environmental Science, University of Eastern Finland, Kuopio, Finland5 Research Unit Analytical BioGeoChemistry, Helmholtz Zentrum München, Neuherberg, Germany
Supplemental Material
Table S1: Experimental engine parameters
Engine model 1 VDS 18/15
Method of operationFour stroke diesel, direct
injected, compressor charged
Amount of cylinders 1
Valves 4
Stroke 180 mm
Bore 150 mm
Length of connecting rod 332 mm
Nominal speed 1,500 min-1
Compression ratio 13
Maximum power 80 kW
Nominal power 60 kW
Table S2: Air-fuel equivalence ratios at different engine loads
Engine load [%] DF [] HFO []
100 2,79 2,88
75 2,47 2,29
50 2,78 2,53
25 3,36 3,00
Table S3: Fuel properties of heavy fuel oil
Parameter Test procedure Unit HFO 180
Kin. viscosity at 50°C ASTM D 7042 mm² s-1 188,83
Density at 15°C ISO 12185 kg m-3 968,7
CCAI - - 838
Sulfur DIN 51400-10 % (m/m) 1,6
Heating value DIN 51900-1,-3 J g-1 38759
C % (m/m) 83,47
H % (m/m) 11,08
Vanadium Mg kg-1 76
Water ISO 12937 (0,50 %(V/V)) 1,68 (0,61 %(V/V))
Ash ISO 6245 % (m/m) 0,06
Off-Line Analysis
Organic carbonyls from the gas phase were analysed with a Shimadzu GC-MS system (model
GCMS-QP2010) using a BPX5 (SGE, Ringwood Victoria, Australia) capillary column (25m×0.25 mm
ID,0.25 µm film thickness). Identification and quantifications of each carbonyl compound (CC)
DNPH hydrazone was done using three unique characteristic for each compound, retention time Rt,
target and reference mass fragment(Reda et al., 2014). The following carbonyls were quantified:
Formaldehyde, Acetaldehye, Propanal, Acetone, Acrolein, iso-Butanal, Butanal, 2-Butanone,
Methacrolein, iso-Pentanal, Pentanal.
TEM Analysis: The single particle morphology was observed using a field emission TEM (JEM
2100F, JEOL Ltd., Japan) operated at 200 kV acceleration voltage. The elemental composition of the
particles was studied using energy dispersive X-ray spectroscopy (EDS, NORAN System 7, Thermo
Scientific, USA).The primary particle diameter of particles was estimated as mean of 68 single
measurements from the TEM images. The accuracy of the measurement was given by the standard
deviation of the single measurements.
Inorganic elements were determined from PTFE filters using inductively coupled plasma atomic
emission spectroscopy. Filter samples were transferred into closed quartz vessels and digested with
HNO3, suprapure, subboiling distilled (Merck, Darmstadt) in a microwave system Multiwave 3000
(Anton Paar). The resulting solution was filled up exactly to 30 mL with Milli-Q H2O and was then
ready for element determination. An ICP-AES „Optima 7300 DV (Perkin Elmer, Germany) was used
for the determination of the following elements(measured spectral element lines in nm): Al (167.078),
As (189.042), B (249.773), Ba (455.404), Be (313.042), Bi (223.061), Ca (183.801),Cd (214.438), Co
(228.616), Cr (267.716), Cu (324.754), Fe (259.941), Hg (184.950), K (766.491) Li (670.780), Mg
(279.079), Mn (257.611), Mo (202.030), Na (589.592), Ni (231.604), P (177.495), Pb (220.353), S
(182.034), Sb (206.833), Se (196.090), Sn (189.991), Sr (407.771), Ti (334.941), V (292.464), W
(207.911), and Zn(213.856) in filter leachates. Sample introduction was carried out by a peristaltic
pump, connected to a micromist nebulizer with a cyclon spray chamber. The RF power was set to
1400 W, the plasma gas was 15 L Ar /min, whereas the nebulizer gas was 0.6 L Ar/min. Regularly
after ten measurements three blank determinations and a control determination of a certified standard
(CPI) for all mentioned elements were performed. Calculation of results was carried out on a
computerized lab-data management system, relating the sample measurements to calibration curves,
blank determinations and control standards.
EC/OC analysis: For EC/OC analysis an area of 0.5 cm2 of the filter was placed at the sample holder
of the carbon analyser and inserted into the oven. During heating organic compounds are desorbed
from the particles. According to the Improve A protocol (Chow 2007) 7 fractions (four for OC and 3
for EC) were detected and quantified by a flame ionization detector (FID). The oven of the carbon
analyser was linked via a small quartz tube and a heated, deactivated quartz capillary (ID = 280 µm) to
a time-of-flight mass spectrometer. The resulting transfer flow was ca. 5 ml min -1. The transfer
capillary was heated stepwise from 230 °C at the quartz tube to 245 °C at the inlet of the mass
spectrometer, to prevent condensation of low-volatile compounds inside the capillary. Photo-ionisation
occurred by VUV-photons, generated by multiplication of the fundamental wavelength (1064 nm) of a
pulsed 20 Hz Nd:YAG-laser (Spitlight 400, Innolas GmbH, Krailling, Germany; pulse energy: 15 mJ
at 355 nm, pulse width 215 µs) to 118 nm for SPI and 266 nm for REMPI. The generated ions were
transferred into the flight-tube by delayed extraction and detected on a micro channel plate. By
averaging 80 consecutive laser pulses, a mass spectrum was generated every four seconds. By
additionally averaging all mass spectra from OC1 and OC2on the one hand and the mass spectra from
OC3 and OC4on the other hand, the mass spectra for the thermodesorption-like fraction OC12 as well as
from pyrolysis-like OC34 respectively were generated. Finally, the mass spectra (OC12 and OC 34
respectively) of five individual samples for each fuel were averaged to create the resulting spectra:
thermodesorption-like OC12 and pyrolysis-like OC34 for each fuel.
In-situ derivatisation thermal desorption gas-chromatography - time-of-flight mass
spectrometry (IDTD-GC-ToFMS, (Orasche et al., 2011)) was used to analyse most of the particulate
organic target analytes . For analysis QFF-Filters were cut into 2x2mm² aliquots. Internal standards
(isotope labelled compounds) was added manually and 10 µl Methyl-trimethylsilyl-trifluoroacetamid
(MSTFA, Macherey-Nagel, Germany) was added automatically by a sampling robot (PAL Focus,
Atas GL, Netherlands) before samples were placed into a direct thermal desorption unit (Linex and
Optic 3, Atas GL, Netherlands) mounted to the gas chromatograph. During 16 minutes of thermal
extraction MSTFA vapour was continuously added to the carrier gas stream of 4 ml min-1. After
thermal extraction and derivatisation the flow was set to pure carrier gas (Helium) and reduced to 0.7
ml min-1 with a split flow of 50 ml min-1 and GC-MS run was started. Separation took place on a
BPX5, 25 m, 0.22 mm ID, 0.25 µm film thicknesses capillary column, (SGE, Australia) installed in an
Agilent 6890 gas chromatograph (Agilent, USA). Mass spectrometric detection in the range 35 to 500
m/z was carried out on a Pegasus III ToFMS (Leco, USA) using an acquisition frequency of 25 spectra
per second. Evaluation of mass spectra was done with the ChromaTOF software package (LECO,
USA). Quantification was done using a set of isotope labelled internals standards and external
standard mixtures to obtain the individual response factors. Target analytes, and internal standards are
given in Table S4.
Filter extraction and solid-phase extraction
Quartz fibre filters were extracted in an ice-cooled ultrasonic bath using 25 ml Methanol/Dichloro-
methane (50/50, v/v) for 15 min, repeated twice. The extracts from both extraction steps were
combined, filtered (PTFE filter, 0.2 µm, 25 mm, VWR, Germany) and divided into 3 identical aliquots
for target and non-targeted analyses.
For analysis of methylated and nitro PAH, the extract (16.6 ml) was added by 10 µl of an internal
standard solution (3-nitrofluoranthene-d9) and divided into two parts. One part was reduced to ca. 0.3
ml in a BüchiSyncore platform, (BüchiLabortechnik AG, Switzerland). This volume was transferred
to a 1 ml volumetric flask and filled with hexane. An aliquot of 100 µl was filled into a 4-ml small
reaction vial and evaporated to dryness in a Barkey vapothermmobil S (Barkey GmbH, Germany)
under a gentle stream of nitrogen. The residue was dissolved in 100 µl acetonitrile, placed into an
autosampler vial and stored for potential additional analyses. The remaining 900 µl of the hexane
solution were fractionated and cleaned using solid phase extraction (SPE). The solution was applied to
a glass column (8 ml, UCT, USA) filled with 2 g silica (0.063 – 0.200 mm, VWR, Germany) and 1 g
NA2SO4. Silica was dried at 500°C for 12 h and deactivated with 1.5 % water for 1 h before use. The
column was preconditioned with 13 ml hexane before sample application. The analytes were eluted in
the first fraction with 10 ml hexane (methylated PAHs) and in the third fraction with 20 ml
hexane/dichloromethane (50/50) (nitro-PAH) respectively. The second fraction (8 ml
hexan/dichloromethane (75/25, v/v)) was not used for further analysis. SPE was carried out on a
Visiprep TM SPE 24-port vacuum manifold from Supelco (Sigma-Aldrich, Germany) equipped with a
vacuum pump KNF Laboport from KNF Neuberger (Germany).
Nitro-PAH: A method based on the post-column reduction of nitro-compounds followed by
fluorescence detection of the resulting amino-PAH was used (Delhomme Olivier, 2007;Schauer et al.,
2004). Separation and detection were modified allowing the determination of 1-nitropyrene, 2-
nitropyrene, 2-nitrofluoranthene, and 3-nitrophenanthrene on the HPLC system HP 1100 (Agilent
Technologies, Germany). An additional column thermostat (SunTherm 5-100) for the post-column
was from SunChrom (Germany). The analytical column (MZ-PAH C-18, 5 µm, 250 x 4 mm I.D) was
purchased from MZ Analysentechnik, (Germany). For post-column on-line reduction of nitro-PAH to
the corresponding amino-PAH a second, empty column (50 x 4 mm I.D., manufactured at
HelmholtzZentrum) was filled with platinum/aluminium oxide (5% Pt, VWR, Germany).Nitro-PAH
were separated with a methanol gradient at 308 K and 1 ml/min: The separation started with 44 %
methanol, the organic solvent content was increased to 83.6 % in 26.5 min, held 1.5 min and raised to
100 % 2 min. This composition was kept for 10 min, within the next two min initial conditions were
reached and the system equilibrated for 15 min. Injection volume was 20 µl. Detection and
quantification of the amino-PAH was carried out applying fluorescence detection: 1-aminopyrene (242
nm/435 nm), 2-aminopyrene (242 nm/445 nm), 2-aminofluoranthene (242 nm/515 nm). Although
baseline separation was achieved, time for exact wavelength switching between 1-nitropyrene and 2-
nitrofluoranthene was too short. Therefore two consecutive runs applying identical gradient but
different detection wavelengths, were used. The HPLC method was externally calibrated for the
quantification of 3-nitrophenanthrene, 1-nitropyrene, 2-nitropyrene and 2-nitrofluoranthene. During
preceding studies it was found that the detection limits were not low enough to analyse 3-
nitrofluoranthene, therefore it was excluded. 3-nitrofluoranthene-d9 was used as internal standard.
Calibration curves in the range from 1.2 pg/µl up to 32 pg/µl using chromatographic peak areas versus
concentration were constructed and resulting correlation coefficients of the calibration curves (n = 6)
were all higher than 0.98.
Table S4: Particulate organic target compounds and methods used for quantification
Compound class Compound Method1 Internal standard
PAH Pyrene A D10-PyreneFluoranthene A D10-FluorantheneBenz[a]anthracene A D12-Benz[a]anthraceneChrysene A D12-ChrysenesumBenzofluoranthenes A D12-Benzo[k]fluorantheneBenze[e]pyrene A D12-Benze[e]pyreneBenz[a]pyrene A D12-Benz[a]pyrenePerylene A D12-PeryleneDibenzo[ah]fluoranthene A D14-Dibenzo[ah]fluorantheneIndeno[1,2,3-cd]pyrene A D12-Indeno[1,2,3-cd]pyreneBenzo[ghi]perylene A D12-Benzo[ghi]peryleneCoronene A D12-Coronene
o-PAH 9H-Fluoren-9-one A9,10-Anthracenedione A1,8-Naphthalic anhydride ACyclopenta[def]phenanthrenone A7H-Benz[de]anthracen-7-one ABenz[a]anthracene-7,12-dione A
nitro-PAH 3-Nitrophenanthrene B 3-Nitrofluoranthene-D9
1-nitropyrene B 3-Nitrofluoranthene-D9
n-Alkanes Octadecane A D22-EicosanNonadecane A D22-EicosanEicosane A D22-Eicosan
Heneicosane A D22-EicosanDocosane A D22-EicosanTricosane A D26-TetracosanTetracosane A D26-TetracosanPentacosane A D26-TetracosanHeptacosane A D26-TetracosanNonacosane A D32-TriacontaneTriacontane A D32-TriacontaneHentriacontane A D32-TriacontaneDotriacontane A D32-TriacontaneTritriacontane A D32-TriacontaneTetratriacontane A D32-Triacontane
Hopanes 18(H)-22,29,30-Trisnorhopane A D32-Triacontane17(H)-22,29,30-Trisnorhopane A D32-Triacontane17(H)-22,29,30-Trisnorhopane A D32-Triacontane17(H),21(H)-30-Norhopane A D32-Triacontane17(H),21(H)-30-Norhopane A D32-Triacontane17(H),21(H)-Hopane A D32-Triacontane17(H),21(H)-Hopane A D32-Triacontane22S-17(H),21(H)-Homohopane A D32-Triacontane22R-17(H),21(H)-Homohopane A D32-Triacontane22S-17(H),21(H)-Bishomohopane A D32-Triacontane22R-17(H),21(H)-Bishomohopane A D32-Triacontane
1: A = IDTD-GC-ToFMS, B = HPLC-FLD
Comprehensive two-dimensional GC - time-of-flight mass spectrometry
10 mL of the obtained extract were reduced to 500μL and 10 µL internal standard solution
(acenaphthene d10, benz(a)anthracene d12, benzo(b)fluoranthene d12, chrysene d12, fluoranthene
d12. fluorene d10, perylene d12, phenanthrene d10 a,dpyrene d10 each 0.3 mg/L, Cambridge Isotope
Laboratories, Inc., USA) were added.As inlet system an Optic III (ATAS-GL, Netherlands) was used.
Chromatographic separation occurred on a BPX5, 60 m, 0.25 mm ID, 0.25 µm film thickness (SGE,
Ringwood, Australia) as the first dimension and a BPX50, 1.9 m, 0.1 mm ID, 0.10 µm film thickness
(SGE) as the second dimension column. Modulation period was adjusted to 3 s with a temperature
offset of the modulator of 75 K. The oven was programmed from 40 °C to 160 °C with 15 K/min
followed by a temperature ramp of 2 K/min to 320 °C. Data Processing and Analysis was done with
ChromaTOF. In house written algorithms for compound classification were applied using the
implemented scripting feature(Weggler et al., 2014).
Ultra-high resolution mass spectrometry
LDI-FTICR-MS: Few µl of the diluted fuel (1:2000 in dichloromethane) and 10 to 20 µL of the
extracts were spotted on a stainless steel target and allowed to dry, resulting in a homogenous thin
layer with a spot diameter of about 5 mm. A solariX FT-ICR mass spectrometer (Bruker Daltonik,
Germany) equipped with a 7 T magnet (Bruker Biospin, France) was operated in positive ion mode at
a resolution of 300.000 @ m/z 400. To obtain a high signal-to-noise-ratio500 scans were accumulated.
For data analysis only signals above an S/N of 6 were used. The obtained mass lists were processed
with the Data Analysis 4.0 software and in house written MATLAB and EXCEL routines. The mass
spectra were calibrated externally using a PAH-mixture measured with the same settings, and
internally using the protonated cations of the N1-series covering the whole mass range. The list of
peaks used to calibrate the spectra is provided in Table S1 and S6.
Tuning was performed for a mass-to-charge-interval from 200 to 1000 amu and a 4 M transient
meaning the acquisition of roughly 4 * 106 data points leading to a resolution of around 300,000 @
m/z 400 and an accumulation time of around 2.5 s was used. To obtain a high signal-to-noise-ratio 500
scans were accumulated.For LDI the third harmonic frequency of a Nd:YAG laser (355 nm) was used.
The ionization settings were tuned to obtain a high signal-to-noise ratio (S/N) and low fragmentation
in comparison to Cho et al. [Cho 2012]. Typical parameters were 35 % laser energy, 60 Shots per
Scan, repetition rate of 100 Hz and a laser spot size of about 100 µm in diameter. For comparison
between fuel and extracts three repetition measurements of all samples were taken with almost the
same settings.Sum formula assignment was performed within 1 ppm error range and following
limitations: CcHhNnOoSs, c - unlimited, h- unlimited, 0 ≤ n ≤ 2, 0 ≤ o ≤ 2, 0 ≤ s ≤ 2.
GC-APCI-FTICR-MS Measurements were performed using a CP 3800 gas chromatograph (Agilent,
USA) equipped with a programmable temperature vaporizing injector (model 1079) hyphenated to an
Apex Qe Series II FTMS system (Bruker Daltonics, Germany) in the 7 Tesla magnet.In contrast to the
fuels, which were diluted 1:1000 in Dichloromethane/Methanol (1/1), the filter extracts were
concentrated 5:1 prior to analysis. The analytes were separated on a HT5 column (25 m x 0.53 mm ID,
0.15µm film thickness, SGE). The injector temperature was set to 60 °C for 1 min, ramped with 50
K/min to 300 °C. The oven temperature was started at 40 °C and held for 6 min. Then it was increased
with 10 K/min to 320 °C and held for 15 min. Sample volume was 2 µL. Helium was used as carrier
gas with a flow rate of 10 mL/min. The transfer line to the mass spectrometer was kept at 320 °C and
the GC capillary protruded approximately 1 mm from the exit of the transfer line into the ion source.
The APCI source and the FT-ICR MS were operated in positive ion mode. Data analysis was
performed similar to the LDI measurements.
The source parameters were optimized and applied in the following way: The temperature and flow
rate of dry gas (N2) were 220 °C and 2 L/min. The APCI source temperature was 320 °C and the
pressure of the nebulizer gas (N2) was set to 3.5* 105 Pa. The corona needle current was 3 µA and the
capillary voltage was set to 2,500 V, the spray shield voltage was 1,000 V. Spectra were acquired in
the range of 100 – 600 amu with an acquisition rate of 0.7 Hzand a resolution of 150,000@ m/z 400.
For initial internal mass calibration a fatty acid methyl ester (Fame) mix were used. Additionally
internal recalibration of every spectrum was realized by using siloxane masses out of the column
bleed.The list of peaks used to calibrate the spectra is provided in Tables S7 and S8.
Data analysis was carried out with the following parameters for sum formula assignment:
CcHhNnOoSsSip, c unlimited, h unlimited, 0 ≤ n ≤ 2, 0 ≤ o ≤ 8, 0 ≤ s ≤ 3, 0 ≤ p ≤ 8, and a maximum
error of 1 ppm. Additional data analysis was performed by in-house MATLAB and EXCEL routines.
Table S5: External calibration peaks used for LDI-FTMS: Polycyclic aromatic hydrocarbons (PAH)
# Sum formula
m/z [amu] charge
1 C10H8 128,062051 1+2 C12H8 152,062051 1+3 C12H10 154,077701 1+4 C13H10 166,077701 1+5 C14H10 178,077701 1+6 C16H10 202,077701 1+7 C18H12 228,093351 1+8 C20H12 252,093351 1+9 C22H14 278,109001 1+
10 C22H12 276,093351 1+11 C24H12 300,093351 1+
Table S6: Internal calibration peaks used for LDI-FTMS: CHN1-derivatives / alkylated rows
# Sum formula m/z [amu] charge1 C18H24N 254.19033 1+2 C20H22N 276.17468 1+3 C22H30N 308.23728 1+4 C24H32N 334.25293 1+5 C26H36N 362.28423 1+6 C28H38N 388.29988 1+
7 C30H40N 420.36248 1+8 C32H40N 438.31553 1+9 C34H52N 474.40947 1+
10 C36H60N 506.47203 1+11 C38H56N 526.44073 1+12 C38H60N 530.47203 1+13 C39H60N 542.47203 1+14 C40H60N 554.47203 1+15 C40H66N 560.51898 1+16 C41H66N 572.51898 1+17 C42H64N 582.50333 1+18 C43H70N 600.55028 1+19 C46H72N 638.56593 1+20 C48H84N 674.65983 1+21 C50H88N 702.69113 1+22 C52H86N 724.67578 1+23 C53H86N 736.67578 1+24 C54H86N 748.67578 1+25 C54H98N 760.76938 1+26 C55H94N 768.73808 1+27 C55H98N 772.76938 1+
Table S7: External calibration peaks used for APCI-FTMS: fatty acids
# Sum formula m/z [amu] charge1 C9H19O2 159.13796 1+2 C11H23O2 187.16926 1+3 C13H27O2 215.20056 1+4 C15H31O2 243.23186 1+5 C17H35O2 271.26316 1+6 C19H39O2 299.29446 1+7 C21H43O2 327.32576 1+8 C23H47O2 355.35706 1+9 C25H51O2 383.38836 1+
Table S8: Internal calibration peaks used for APCI-FTMS: silicones / plasticisers
# Sum formula m/z [amu] charge1 C9H11O 135.08044 1+2 C9H13O2 153.09101 1+3 C12H23O2 199.16926 1+4 C6H18O3Si3 22.30637 1+5 C16H33O2 257.24751 1+6 C18H37O2 285.27881 1+7 C8H22O4Si4 295.06171 1+8 C7H22O5Si4 299.06171 1+9 C9H27Si5O5 355.06993 1+
10 C24H39O4 391.28429 1+11 C10H31Si5O5 371.10123 1+
12 C11H33Si6O6 429.08872 1+13 C12H37Si6O6 445.12003 1+14 C12H40NSi6O
6462.14657 1+
15 C13H38O7Si7 503.10752 1+16 C14H43Si7O7 519.13882 1+17 C14H46NSi7O
7536.16537 1+
18 C15H44O8Si8 577.12631 1+19 C16H48O8Si8 593.15761 1+
On-Line Methods
Gaseous emissions (NOx, Total Hydrocarbon (THC), CO, CO2, SO2) were routinely monitored using
AVL CEB II exhaust gas analysers, a state of the art system for emission test bench applications. Raw
gas was taken directly from the exhaust pipe, transported through heated transfer lines and filtered at
180 °C before entering the gas monitors. Table S9summarizes detailed information on the exhaust gas
analysers. To allow for synchronized data acquisition at a sampling frequency of 1 Hz, AVL CEB II
was connected to a data acquisition system on basis of National Instruments™ LabView software as
shown in Figure S1.
Figure S1: Engine experimental setup (p = pressure, T = temperature, °CA = crank angle, Res. = resolution, Freq. = Frequency)
Table S9: Exhaust gas analyzers of AVL CEB II
O2-analyzer CO2-analyzer CO-analyzer THC-analyzer CLD-analyzer SO2-analyzer
Manufacturer H&B H&B H&B H&B ECO-Physics H&B
Type Magnos 16 Uras 14 Uras 14 Multi FID 14 CLD 700 RE ht LIMAS 11
Gas type O2 CO2 CO(L)/CO(H) THC NOx SO2
Measuringrange 0 - 25 % 0 - 20 % 0 - 2500 ppm; 1000 - 100 000 ppm 0 - 1000 ppm 0 - 2200 ppm 0 - 1000 ppm
Measuring type dry dry dry wet wet wet
Single-photon ionization mass spectrometry (SPI-MS): Online analyses of organic gaseous motor
emissions were carried out by mass spectrometric methods. The use of vacuum-ultraviolett (VUV)
photons for ionization allows for a virtually fragment free ionization of a large variety of organic
substances. In the present study, a customized electron beam pumped excimer lamp (EBEL) was
applied as continuous VUV source, emitting light at a central wavelength of 126 nm (9.8±0.4 eV)
from the decay of metastable Ar2* molecules. MgF2 coated mirrors guide the radiation in vacuum
environment and focus it into the acceptance volume of a mass spectrometer where it interacts with an
effusive beam of hot filtered raw gas (300 °C) taken directly from the exhaust pipe. The continuously
produced ions were analysed using an orthogonal time-of-flight mass spectrometer operating at a
repetition rate of 60 kHz (C-Tof, Tofwerk, Switzerland). Figure S2depicts a scheme of the mass
spectrometric system. A mixture of each 10ppm benzene, toluene and p-xylene in nitrogen served as
calibration gas. In case of known ionization cross section values (see (Eschner and Zimmermann,
2011), concentration values can be calculated from measured spectra.
Figure S2: Scheme of the SPI-TOFMS system for online monitoring of the exhaust gas of the ship diesel engine
Resonance-enhanced multiphoton ionization mass spectrometry (REMPI-MS): In contrast to the
SPI-technique, that addresses a wide spectrum of substances, the REMPI-ionization method features a
high selectivity, typically towards aromatic species. A laser source provides intense radiation
(typically >107 W/cm2) in the UV range of the optical spectrum. Since the photon energy is not
sufficiently high (hEI), photo-ionization cannot be induced by a single photon. However, the high
photon density of pulsed laser radiation allows for the absorption of multiple photons, hence
overcoming the ionization barrier. Since transition probabilities are strongly influenced by the energy
match between possible intermediate states and photon energy as well as by the states’ lifetimes, these
schemes are referred as Resonance Enhanced Multiphoton Ionization (REMPI). For the present study,
the fourth harmonic (266 nm, 4.66 eV) of a Nd:YAG-Laser (Big Sky Ultra, Quantel, Germany) with
10 Hz repetition rate and 10 ns pulse width was used as ionizing light source. Since the resulting
intensity of approximately 7x107 W/cm2 is sufficiently high, the unfocused beam was guided into the
acceptance volume of a commercial reflectron time-of-flight mass spectrometer (CTF10, Kaesdorf,
Germany), where it intersects an effusive molecular beam of the undiluted and hot filtered exhaust gas
(temperature 300°C). Individual ionization cross sections of the compounds may differ greatly (Adam
et al., 2012;Boesl et al., 1981). Data acquisition was accomplished using a dual channel 8-bit averager
(Acqiris AP240, Agilent Technologies, USA).
Aerosol mass spectrometer (AMS): A High-resolution Time-of-Flight Aerosol Mass Spectrometer
(HR-ToF-AMS, Aerodyne Research Inc., USA) was used to measure the sub-micrometer non-
refractory particles from the ship diesel engine emissions, sampled from the diluted and cooled (20°C)
exhaust gas. The particle beam is formed by sampling through a 100 µm critical orifice inlet and
subsequent focusing into a tight particle beam using an aerodynamic lens system. By expansion into
high vacuum conditions particles are accelerated and hit a hot conical surface (heater at 600°C). Non-
refractory components of the particles are evaporating immediately. The evaporated constituents are
continuously ionized by 70 eV electrons. Ion masses are analysed by an orthogonal extraction
reflectron TOF-system in V-mode configuration (single reflection). A scheme of the instrument is
depicted in Figure S3.The instrument was calibrated with respect to the particle size as well as
regarding the ionization efficiency which accounts for ionization ratio, MS-transmission and ion
detection. Monodisperse, spherical polystyrene latex particles (Thermo Scientific, USA) with sizes
from 92 nm to 800 nm were used to calibrate the particle TOF. The ionization efficiency calibration
was performed using 400 nm NH4NO3 particles, mobility classified by a differential mobility analyser
(Model 3080, TSI Inc., USA) and measured in the Brute-Force-Single Particle (BFSP) mode, featuring
single particle detection. In this mode, the average number of detected ions per particle was calculated
from the signal of a single 400 nm particle compared to the single ion pulse. Thereby, the ionization
efficiency was determined to a value of 2•10-8 - 3•10-8.
Figure S3: Scheme of the AMSinstrument for online monitoring of exhaust particles of the ship diesel engine
Aethalometer: Black carbon (BC) is defined as a strongly light absorbing material of several linked
forms of carbon, measured by optical methods. As the wavelength becomes shorter, approaching the
UV (<400 nm), also organic compounds (e.g. polycyclic aromatic hydrocarbons, PAH) from typical
combustion processes serve as absorbents. This fraction is a part of the organic carbon (OC) and is
also called 'brown carbon' (BrC) or 'equivalent carbon (Pavese et al., 2012).The instrument used in this
study to estimate BC concentration is a multi-wavelength aethalometer (Model AE33, MAGEE
Scientific, USA). The light attenuation by particulate material continuously deposited on a Teflon-
coated glass fibre filter tape is measured at wavelengths ranging from UV to IR (370, 470, 520, 590,
660, 880 and 990 nm). The instrument is equipped with the patented DualSpotTM technology,
accounting for filter loading effects. Built-in software based on the Magee algorithm (Esposito et al.,
2012) analyses the multi-wavelength data in real-time and fits the absorption spectrum to determine
the Ångström Exponent. For the experiments presented here, the aethalometer has been operated with
a flow rate of 2 l/min and a time-resolution of 1 minute. Absorbance signals at 370 nm (UVPM, UV-
absorbing Particulate Material) and 880 nm (BC) were interpreted. The difference between the UVPM
and BC values represents the brown carbon (BrC).The operation principle of the Aethalometer, related
theory and the algorithm for calculating the BC concentration are described in more detail by (Arnott
et al., 2005).
Particle Sizing: Size distribution data was determined using a scanning mobility particle sizer (SMPS,
model 3080 and CPC, model 3022a, TSI Inc., USA) and an electrical low pressure impactor (ELPI,
Dekati, Finland).
SMPS data were recorded from 15 nm to 615 nm in logarithmically equal size bins every 135 s.
Dilution factors were taken from the dilution system and averaged for one scanning time period.
Samples with excessive dilution factors were skipped. Size distributions were averaged channel wise,
calculating standard deviation and weighted averages from all valid data sets. Particle size dependent
emission factors were calculated from the SMPS particle number distributions. Mean size distributions
(emission factors, # kWh-1) for the different engine loads are given in Figure S5.
ELPI: The ELPI (Electrical Low Pressure Impactor) is a twelve stage low pressure cascade impactor.
Particles are guided through a unipolar corona discharge unit. Charged particles are impacted
according to their sizes on one of the twelve stages. Working pressure on the last stage is 104 Pa. The
electrical charge on each stage is detected by a multi canal electrometer and is directly proportional to
the number of particles. With the known properties of the impactor and the size dependent charging
efficiency size distributions are calculated. The obtained aerodynamic size range is between 14 nm
and 6.3 µm.The time resolved data for DF and HFO are shown in Figure S6and S7.
Results
Figure S4: A. DF soot structure, with the graphitic layers visible. In the insert, the general variation of the agglomerate size can be observed. B. HFO soot structure, with the graphitic layers and metal nuclei visible. In the insert, the general variation of the particle size can be observed.
Table S10: Emission factors of elements in emissions (µg kWh-1) from DF and HFO operated ship engine.
DF HFO
µg kWh-1
Standard Deviation
Minµg kWh-1
Maxµg kWh-1 µg
kWh-1Standard Deviation
Minµg kWh-1
Maxµg kWh-1
Al 150 48 52 190 260 62 200 370As 28 8.9 16 37 19 7.2 13 34Ba 7.0 2.1 3.1 9.0 480 100 310 630Ca 580 270 280 980 2700 540 2200 3800Cd 5.3 1.7 3.0 6.9 5.4 0.98 4.4 7.1Co 10 3.2 5.9 13 8.4 2.1 6.3 12Cr 28 32 5.6 91 23 5.4 18 33Cu 23 13 12 48 360 55 290 430Fe 220 150 80 480 5300 980 3700 6800K 230 71 130 300 340 49 270 410Mg 260 80 150 340 830 110 690 1000Mn 6.2 1.7 3.0 8.1 140 17 120 170Mo 12 3.8 6.8 16 10 2.2 8.4 14Na 340 110 200 450 580 93 450 700Ni 26 19 8.1 63 2000 190 1700 2300P 280 87 160 360 2100 240 1800 2600Pb 11 2.6 5.7 13 85 20 69 120S 320 97 160 460 19000 2300 17000 24000Sb 29 9.1 17 38 20 7.5 13 35Se 30 11 16 45 26 14 17 53Sn 14 4.4 8.5 19 12 7.4 3.3 25Sr 4.7 1.4 2.7 6.0 35 5.9 29 46Ti 19 15 6.9 48. 7.4 2.5 5.5 12V 45 15 19 63 7900 640 7100 8900Zn 90 31 48 130 1300 220 1100 1700
Table S11: Emission factors of carbonaceous compounds in emissions (µg kWh-1) from DF and HFO operated ship engine.
DF HFO
Mean Standard Deviation Min Max Mean Standard
Deviation Min Max
EC mg kWh-1 51 13 34 63 56 9.3 47 72OC mg kWh-1 86 13 74 110 270 67 200 350Pyrene µg kWh-1 5.5 1.6 3.2 7.2 21 2.2 19 24Fluoranthene µg kWh-1 7.8 4.7 2.4 16 36 4.6 29 43Benz[a]anthracene µg kWh-1 0.66 0.16 0.43 0.89 9.3 1.3 7.6 11Chrysene µg kWh-1 3.4 0.94 1.7 4.4 67 4.9 62 75sumBenzofluoranthenes µg kWh-1 < LOQ 8.3 1.2 6.9 10Benze[e]pyrene µg kWh-1 < LOQ 12 1.4 10 14Benz[a]pyrene µg kWh-1 < LOQ 2.8 0.58 2.4 3.8Perylene µg kWh-1 < LOQ 1.2 0.18 1.1 1.5Dibenzo[ah]fluoranthene µg kWh-1 < LOQ 2.3 0.44 2.0 3.2Indeno[1,2,3-cd]pyrene µg kWh-1 < LOQ 3.5 3.2 1.6 9.1Benzo[ghi]perylene µg kWh-1 < LOQ 4.1 0.52 3.6 5.0Coronene µg kWh-1 < LOQ 1.2 0.27 0.87 1.71-Methylnaphthalin µg kWh-1 11 3.6 6.1 14 7.3 2.7 4.9 132-Methylnaphthalin µg kWh-1 13 4.0 6.9 16 8.3 3.1 5.4 141,2-Dimethylnaphthalin µg kWh-1 10 3.4 6.0 14 7.3 2.7 4.9 121,6-Dimethylnaphthalin µg kWh-1 11 3.7 6.5 15 8.0 3.1 5.5 142,6-Dimethylnaphthalin µg kWh-1 12 4.2 7.2 17 8.8 3.2 6.1 151-Methylphenanthren µg kWh-1 23 6.1 15 29 78 22 59 1102-Methylphenanthren µg kWh-1 10 2.1 7.3 13 85 23 64 1103-Methylphenanthren µg kWh-1 7.2 1.2 5.4 9.0 52 16 38 749-Methylphenanthren µg kWh-1 6.1 1.2 4.2 7.7 46 11 35 60
2-Methylanthracen µg kWh-1 17 4.9 11 22 19 6.1 12 301,7-Dimethylphenanthren µg kWh-1 31 8.7 19 41 71 16 55 1001-Methyl-7-isopropylphenanthrene µg kWh-1 29 8.9 17 39 28 6.7 21 411-Methylpyrene µg kWh-1 15 4.6 8.5 20 32 6.9 26 434-Methylpyrene µg kWh-1 17 5.0 10 22 42 8.5 35 553-Methylchrysene µg kWh-1 13 3.8 7.4 17 99 18 75 1206-Methylchrysene µg kWh-1 46 14 29 64 44 11 34 669H-Fluoren-9-one µg kWh-1 9.7 4.5 5.1 15 24 11 11 389,10-Anthracenedione µg kWh-1 34 6.6 22 42 68 14 43 821,8-Naphthalic anhydride µg kWh-1 14 5.1 7.0 20 24 5.1 16 29Cyclopenta[def]phenanthrenone µg kWh-1 1.3 0.70 0.38 2.3 4.2 0.92 2.5 5.27H-Benz[de]anthracen-7-one µg kWh-1 < LOQ 4.3 0.52 3.7 4.9Benz[a]anthracene-7,12-dione µg kWh-1 < LOQ 4.0 0.81 2.8 5.33-Nitrophenanthrene µg kWh-1 0.18 0.02 0.16 0.21 0.25 0.03 0.22 0.301-nitropyrene µg kWh-1 0.044 0.004 0.035 0.048 0.013 0.002 0.010 0.015Octadecane µg kWh-1 42 16 28 69 150 67 59 220Nonadecane µg kWh-1 93 36 65 150 250 110 120 380Eicosane µg kWh-1 200 100 110 380 350 130 190 500Heneicosane µg kWh-1 140 25 99 170 230 65 170 350Docosane µg kWh-1 63 38 28 120 220 69 140 340Tricosane µg kWh-1 23 16 8.6 48 120 38 75 170Tetracosane µg kWh-1 18 14 6.2 38 140 54 77 240Pentacosane µg kWh-1 8.9 6.7 2.4 20 140 45 85 210Heptacosane µg kWh-1 7.4 4.0 1.9 14 130 52 68 210Nonacosane µg kWh-1 4.8 2.4 1.7 8.8 89 21 62 120Triacontane µg kWh-1 3.5 1.5 1.4 5.8 56 13 38 74Hentriacontane µg kWh-1 2.2 0.72 1.0 2.9 47 6.9 40 54
Dotriacontane µg kWh-1 1.6 0.76 0.51 2.6 52 13 37 72Tritriacontane µg kWh-1 < LOQ 46 17 27 70Tetratriacontane µg kWh-1 < LOQ 36 11 28 5118(H)-22,29,30-Trisnorhopane µg kWh-1 < LOQ 16 3.4 12 2217(H)-22,29,30-Trisnorhopane µg kWh-1 < LOQ 30 9.5 18 4117(H)-22,29,30-Trisnorhopane µg kWh-1 < LOQ 6.3 1.7 3.5 8.217(H),21(H)-30-Norhopane µg kWh-1 8.9 3.8 5.1 14 100 33 56 14017(H),21(H)-30-Norhopane µg kWh-1 < LOQ 8.0 2.3 5.7 1017(H),21(H)-Hopane µg kWh-1 11 3.8 6.6 16 120 30 84 16017(H),21(H)-Hopane µg kWh-1 < LOQ 10 1.0 9.3 11.22S-17(H),21(H)-Homohopane µg kWh-1 6.6 2.3 3.7 9.5 68 13 49 8922R-17(H),21(H)-Homohopane µg kWh-1 5.3 1.4 3.6 7.2 50 9.6 39 6722S-17(H),21(H)-Bishomohopane
µg kWh-14.4 1.3 2.5 6.3 53 5.1 47 61
22R-17(H),21(H)-Bishomohopane
µg kWh-13.0 0.64 1.9 3.7 42 7.3 32 51
Figure S5: Mean particle emission factors dEf/ dlogDp in particles per kWh engine output for DF and HFO averaged for each of the four loads.
Figure S6: Particle size distribution over 240 min (two cycles) from DF emissions measured by the ELPI. Peak maxima occurred during the switching of the engines power.
Figure S7: Particle size distribution over 240 min (two cycles) from HFO emissions measured by the ELPI.
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