6 research outputs found
Hyphenation of Thermal Analysis to Ultrahigh-Resolution Mass Spectrometry (Fourier Transform Ion Cyclotron Resonance Mass Spectrometry) Using Atmospheric Pressure Chemical Ionization For Studying Composition and Thermal Degradation of Complex Materials
In this study, the hyphenation of
a thermobalance to an ultrahigh-resolution
Fourier transform ion cyclotron resonance mass spectrometer (UHR FTICR
MS) is presented. Atmospheric pressure chemical ionization (APCI)
is used for efficient ionization. The evolved gas analysis (EGA),
using high-resolution mass spectrometry allows the time-resolved molecular
characterization of thermally induced processes in complex materials
or mixtures, such as biomass or crude oil. The most crucial part of
the setup is the hyphenation between the thermobalance and the APCI
source. Evolved gases are forced to enter the atmospheric pressure
ionization interface of the MS by applying a slight overpressure at
the thermobalance side of the hyphenation. Using the FTICR exact mass
data, detailed chemical information is gained by calculation of elemental
compositions from the organic species, enabling a time and temperature
resolved, highly selective detection of the evolved species. An additional
selectivity is gained by the APCI ionization, which is particularly
sensitive toward polar compounds. This selectivity on the one hand
misses bulk components of petroleum samples such as alkanes and does
not deliver a comprehensive view but on the other hand focuses particularly
on typical evolved components from biomass samples. As proof of principle,
the thermal behavior of different fossil fuels: heavy fuel oil, light
fuel oil, and a crude oil, and different lignocellulosic biomass,
namely, beech, birch, spruce, ash, oak, and pine as well as commercial
available softwood and birch-bark pellets were investigated. The results
clearly show the capability to distinguish between certain wood types
through their molecular patterns and compound classes. Additionally,
typical literature known pyrolysis biomass marker were confirmed by
their elemental composition, such as coniferyl aldehyde (C<sub>10</sub>H<sub>10</sub>O<sub>3</sub>), sinapyl aldehyde (C<sub>11</sub>H<sub>12</sub>O<sub>4</sub>), retene (C<sub>18</sub>H<sub>18</sub>), and
abietic acid (C<sub>20</sub>H<sub>30</sub>O<sub>2</sub>)
On-Line Process Analysis of Biomass Flash Pyrolysis Gases Enabled by Soft Photoionization Mass Spectrometry
In the current discussion about future energy and fuel
supply based on regenerative energy sources, the so-called second-generation
biofuels represent a vitally important contribution for the provision
of carbon-based fuels. In this framework, at the Karlsruhe Institute
of Technology (KIT), the bioliq process has been developed, by which
biomass is flash-pyrolyzed at 500 °C for the production of so-called
biosyncrude, a suspension of the pyrolysis liquids and the remaining
biochar. However, little is known about the composition of the pyrolysis
gases in this process with regard to different biomass feedstock and
process conditions, and the influence on the subsequent steps, namely,
the gasification and subsequent production of biofuels or base materials.
Time-of-flight mass spectrometry (TOFMS) with two soft (i.e., fragmentation
free) photoionization techniques was for the first time applied for
on-line monitoring of the signature organic compounds in highly complex
pyrolysis gases at a technical pyrolysis pilot plant at the KIT. Resonance-enhanced
multiphoton ionization with TOFMS using UV laser pulses was used for
selective and sensitive detection of aromatic species. Furthermore,
single-photon ionization using VUV light supplied by an electron beam-pumped
excimer light source was used to comprehensively ionize (nearly) all
organic molecules. For the miscellaneous biomass feeds used, distinguishable
mass spectra with specific patterns could be obtained, mainly exhibiting
typical pyrolytic decomposition products of (hemi)cellulose and lignin
(phenol derivatives), and nitrogen-containing compounds in some cases.
Certain biomasses are differentiated by their ratios of specific groups
of phenolic decomposition products. Therefore, principal component
and cluster analysis describes the varied pyrolysis gas composition
for temperature variations and particularly for different biomass
species. The results can be integrated in the optimization of the
bioliq process
Experimental set-up and global omics analyses.
<p>(A) An 80 KW common-rail-ship diesel engine was operated with heavy fuel oil (HFO) or refined diesel fuel (DF). The exhaust aerosols were diluted and cooled with clean air. On-line real-time mass spectrometry, particle-sizing, sensor IR-spectrometry and other techniques were used to characterise the chemical composition and physical properties of the particles and gas phase. Filter sampling of the particulate matter (PM) was performed to further characterise the PM composition. Lung cells were synchronously exposed at the air-liquid-interface (ALI) to aerosol or particle-filtered aerosol as a reference. The cellular responses were characterised in triplicate at the transcriptome (BEAS-2B), proteome and metabolome (A549) levels with stable isotope labelling (SILAC and <sup>13</sup>C<sub>6</sub>-glucose). (B) Heatmap showing the global regulation of the transcriptome, proteome and metabolome.</p
Chemical and physical aerosol characterisation.
<p>(A) The ship diesel engine was operated for 4 h in accordance with the IMO-test cycle. (B) Approximately 28 ng/cm<sup>2</sup> and 56 ng/cm<sup>2</sup> were delivered to the cells from DF and HFO, respectively, with different size distributions. The HFO predominantly contained particles <50 nm, and the DF predominantly contained particles >200 nm, both in mass and number. (C) Number of chemical species in the EA particles. (D) Transmission electron microscope (TEM) images and energy-dispersive X-ray (EDX) spectra of DF-EA and HFO-EA; heavy elements (black speckles, arrow); and contributions of the elements V, P, Fe and Ni in the HFO particles using EDX (* = grid-material). (E) Exemplary EA concentrations (right) and concentration ratios (left) for particulate matter-bound species. For all experiments, n = 3.</p
Summary of the main HFO- and DF-particle exposure effects.
<p>The arrows indicate the direction of regulation for cellular functions derived from the most statistically significant enriched Gene Ontology terms from the transcriptome, proteome, and metabolome (details in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126536#pone.0126536.s012" target="_blank">S2 Table</a>).</p><p><sup>x</sup> BEAS-2B up, A549 down</p><p>* BEAS-2B down, A549 up</p><p>Summary of the main HFO- and DF-particle exposure effects.</p
Effects of shipping particles on lung cells.
<p>The net effects from the particles were referenced against the gaseous phase of the emissions. (A) Number of the regulated components in the transcriptome shows more genes regulated by the DF than the HFO particles (in BEAS-2B cells). Similar results were observed for the proteome (B) and metabolome (C) (in A549 cells). (D) Meta-analyses for the transcriptome and proteome using the combined Gene Ontology (GO) term analysis of the 10% most regulated transcripts and proteins. Individual GO terms are listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0126536#pone.0126536.s012" target="_blank">S2 Table</a>; the hierarchical pathways are indicated on the right. (E) Gene regulation of Wiki-pathway bioactivation; (F) gene regulation of Wiki-pathway inflammation; g, secreted metabolites; and h, metabolic flux measurements using <sup>13</sup>C-labelled glucose. For all experiments, n = 3.</p