Fast pyrolysis bio-oils are feasible energy carriers and a potential source of chemicals. Detailed characterization of bio-oils is essential to further develop its potential use. In this study, quantitative 13C nuclear magnetic resonance (13C NMR) combined with comprehensive two-dimensional gas chromatography (GC × GC) was used to characterize fast pyrolysis bio-oils originated from pinewood, wheat straw, and rapeseed cake. The combination of both techniques provided new information on the chemical composition of bio-oils for further upgrading. 13C NMR analysis indicated that pinewood-based bio-oil contained mostly methoxy/hydroxyl (≈30%) and carbohydrate (≈27%) carbons; wheat straw bio-oil showed to have high amount of alkyl (≈35%) and aromatic (≈30%) carbons, while rapeseed cake-based bio-oil had great portions of alkyl carbons (≈82%). More than 200 compounds were identified and quantified using GC × GC coupled to a flame ionization detector (FID) and a time of flight mass spectrometer (TOF-MS). Nonaromatics were the most abundant and comprised about 50% of the total mass of compounds identified and quantified via GC × GC. In addition, this analytical approach allowed the quantification of high value-added phenolic compounds, as well as of low molecular weight carboxylic acids and aldehydes, which exacerbate the unstable and corrosive character of the bio-oil.

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The conventional one‐at‐a‐time strategy to evaluate catalysts is inefficient and resource intensive. Even a fractional factorial design takes weeks to control for temperature, pressure, composition, and stability. Furthermore, quantifying day‐to‐day variability and data quality exacerbates the time sink. High‐throughput catalyst testing (HTCT) with as many as 64 parallel reactors reduces experimental time by two orders of magnitude and decreases the variance, as it is capable of quantifying random errors. This approach to heterogeneous catalyst development requires dosing each reactor precisely with the same flow and composition, controlling the temperature and identifying the isothermal zone, on‐line analysis of the gas‐phase, and a common back pressure regulator to maintain constant pressure. Silica capillary or microfluidic distribution chip manifolds split a common feed stream precisely (standard deviation <0.5%), thus guaranteeing reproducibility. With these systems, experimenters shift their focus from operating a single reactor to careful catalyst synthesis, sometimes delicate catalytic reactor loadings, and the handling, processing, and analysis of massive amounts of data. This review presents an overview of the main elements of HTCT, its applications, potential sources of uncertainty, and a set of best practises derived from scientific literature and research experience. A bibliometric analysis of articles Web of Science indexed from 2015–2020 grouped research into five clusters: (1) discovery, directed evolution, enzymes, and complexes; (2) electrocatalysis, reduction, adsorption, and nanoparticles; (3) hydrogen, oxidation, and stability; (4) DFT, combinatorial chemistry, and NH3; and (5) graphene and carbon.

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Anisole hydrodeoxygenation over a nonsulfided CoMo/Al 2 O 3 catalyst was investigated as a model reaction for fast pyrolysis oil upgrading. Intrinsic kinetic data have been acquired in a gas-phase plug-flow reactor at temperatures ranging from 548 to 623 K, a total pressure amounting to 0.5 MPa, a space time between 95 and 400 kg cat s mol anisole −1 , and a hydrogen to anisole molar ratio from 50 to 400. A minimum of 16 h on stream stable anisole conversion was observed. The catalyst mainly exhibited anisole demethylation and phenol methylation to cresol, rather than hydrogenation or hydrodeoxygenation. Demethylation and isomerization reactions are followed by hydrodeoxygenation. Additionally, cresol is formed via phenol methylation. Rival mechanisms were proposed, and corresponding Langmuir−Hinshelwood−Hougen−Watson elementary step based kinetic models were derived. Each of the proposed models accounted for the interaction of the species with the catalyst surface as well as for the surface reactions. For each catalytic cycle a rate-determining step was identified. Statistical analysis combined with an assessment of physical meaning of the model parameters allowed the proposal that for both demethylation and hydrodeoxygenation reactions C Ar −O bond cleavage is facilitated by a prior hydrogen addition. Cresol is mainly formed from phenol methylation rather than from anisole isomerization occurring at a rate which is several orders of magnitude slower than that of the other reactions considered.