A laboratory-scale reactor was used to produce pyrolysis oils from Finnish silver birch hardwood (Betula pendula). The resulting wood distillates were characterized by ultrahigh-resolution (12 T) Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry coupled with negative-ion electrospray ionization (ESI). Two different pyrolysis temperatures were tested: 300 and 380 °C (the resulting oil samples were named as Oil-300 and Oil-380, respectively). The detected species were sorted on the basis of heteroatom class, carbon number, and double bond equivalent (DBE). About 1200 and 1400 unique compounds were identified from the ESI FT-ICR spectra of Oil-300 and Oil-380, respectively. These were mainly oxygencontaining compounds (O x heteroatom classes, with x = 2−14), comprising up to 90% of all identified compounds. The compounds in the O 2 , O 3 , and O 4 classes comprised of different fatty acids, hydroxy/epoxy fatty acids, and diacids. The compounds in the O 5 −O 8 classes comprised of mainly lignin degradation products and phenolic extractives. The compounds in the O 9 −O 14 classes comprised of both low-and high-DBE compounds. Upon increasing the temperature from 300 to 380 °C, many compounds showed an overall decrease in their DBE and carbon number. The distribution of fatty acids in Oil-300 qualitatively matches the known lipid-derived fatty acid composition of silver birch. At a higher pyrolysis temperature (380 °C), hydrogenation of unsaturated C 18 fatty acids toward fully saturated compounds was observed.

Ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry was used for compositional analysis of polar and asphaltene fractions of complex oil residues. The samples were collected before and after the processing of oil in a residue hydrocracking unit, in which the feed oil was the vacuum distillation residue of the crude oil, and the product sample was the residue collected after the processing. From the asphaltene fraction, as many as ∼26 000 peaks were detected by atmospheric pressure photoionization and more than ∼33 000 peaks by positive-ion electrospray ionization (ESI), with up to 18 distinct heteroatom classes identified. Negative-ion ESI provided complementary information through selective ionization of acidic compounds. The detected species were sorted based on heteroatom class, carbon number and aromaticity (double bond equivalence, i.e. number of rings + double bonds to carbon). The N 1 class compounds were predominant in both fractions of the feed and product oils. The sulfur-containing compounds were mainly degraded or removed during the processing as expected. Vanadyl porphyrins (heteroatom class N 4 O 1 V 1 ), detected in the asphaltene fraction of the feed oil, were not observed in the product oil fractions that is consistent with their efficient removal. Increase in the aromaticity for the most heteroatom classes was generally noticed in both polar and asphaltene fractions.

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The noncovalent complexation of tetraethyl and tetraphenyl resorcinarenes with mono-, di-, and oligosaccharides was studied with negative-polarization electrospray ionization quadrupole ion trap and electrospray ionization Fourier-transform ion cyclotron resonance mass-spectrometric analysis. The saccharides formed 1:1 complexes with deprotonated resorcinarenes, which exhibited clear size and structure selectivity in their complexation. In the case of the monosaccharides, hexoses formed much more abundant and kinetically stable complexes than pentoses or deoxyhexoses. A comparison of the mono-, di-, and oligosaccharides revealed that both the relative abundance and stability of the complexes increase up to biose and triose, but start to decrease after that point, as the length of the oligosaccharide is increased. This behavior was rationalized by comparing the lowest-energy conformations of the complexes formed between the resorcinarene and oligosaccharides. This comparison was achieved by using theoretical calculations and X-ray crystal studies.

Two gas oil samples, untreated feed and hydrotreated product oil, were analyzed. Both basic and acidic polar species were detected by electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry, and the detected species were characterized on the basis of their elemental compositions. Samples were real refinery samples, with one sample being a certain distillation fraction of crude oil (feed) and the other sample being a hydrotreated feed oil (product). Comparison of the compositions of untreated and hydrotreated oil provides insight into (1) compounds that are resistant to processing, (2) compounds that are removed/degraded by processing, and (3) new compounds that are produced during processing. N 1 class compounds were found to be the most abundant basic species in both oil samples. In addition, the proportion of N 1 class compounds was clearly greater in the product oil than in the feed oil, which indicates that these basic species must be resistant to removal by hydrotreatment. All basic N x O y -, N x S z -, and N x O y S z -containing compounds that were detected in the feed oil were completely removed by hydrotreatment. However, some of the O y S z compounds remained in the oil after hydrotreatment. Negative-ion ESI revealed that the majority of the acidic polar species in the product sample were N 1 compounds, which was also the predominant class in the feed sample. The second most abundant species were the O y -containing compounds. All of the O 1 compounds that were detected in the feed oil were degraded during the hydrotreatment process, as were the O 2 compounds with double-bond equivalent (DBE) values >4. Acidic N x O y -, N x S z -, O y S z -, and N x O y S z -containing compounds were not completely removed by the processing, but the relative abundances of these species were no longer significant in the product oil.