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This study aimed to explore the impact of varying amounts of added Au (0.5 to 2 wt.%) and the structural characteristics of anatase TiO2 supports (nanoparticles (TP, SBET = 88 m2/g) and nanorods (TR, SBET = 105 m2/g)) on the catalytic efficiency of TiO2+Au catalysts in eliminating the herbicide glyphosate from aqueous solutions via the catalytic wet air oxidation (CWAO) process. The investigation was conducted using a continuous-flow trickle-bed reactor. Regardless of the TiO2 support and the amount of Au added, the addition of Au has a positive effect on the glyphosate degradation rate. Regarding the amount of Au added, the highest catalytic activity was observed with the TP + 1% Au catalyst, which had a higher Schottky barrier (SB) than the TP + 2% Au catalyst, which helped the charge carriers in the TiO2 conduction band to increase their reduction potential by preventing them from returning to the Au. The role of glyphosate degradation product adsorption on the catalyst surface is crucial for sustaining the long-term catalytic activity of the investigated TiO2+Au materials. This was particularly evident in the case of the TR + 1% Au catalyst, which had the highest glyphosate degradation rate at the beginning of the CWAO experiment, but its catalytic activity then decreased over time due to the adsorption of glyphosate degradation products, which was favoured by the presence of strong acidic sites. In addition, the TR + 1% Au solid had the smallest average Au particle size of all analyzed materials, which were more easily deactivated by the adsorption of glyphosate degradation products. The analysis of the degradation products of glyphosate shows that the oxidation of glyphosate in the liquid phase involves the rupture of C–P and C–N bonds, as amino-methyl-phosphonic acid (AMPA), glyoxylic acid and sarcosine were detected. [ABSTRACT FROM AUTHOR]

The fluctuating nature of renewable energies results in the need for sustainable storage technologies to defossilize the energy system without other negative consequences for humans and the environment. In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2024 and 2050 were investigated using life cycle assessment. A best- and worst-case scenario for technology development until 2050 was evolved using cross-consistency analysis and a morphological field, based on which the data for the ecological models were determined. The results show that the plant scale-up has a very positive effect on the ecological consequences of methanation. In the best-case scenario, the values are a factor of 23–780 lower than those of the actual plant today. A hot-spot analysis showed that electrolysis operation has an especially large impact on total emissions. The final Monte Carlo simulation shows that the technology is likely to achieve a low global warming potential with a median of 104.0 kg CO2-eq/MWh CH4 and thus can contribute to decarbonization. [ABSTRACT FROM AUTHOR]

The fluctuating nature of renewable energies results in the need for sustainable storage technologies to defossilize the energy system without other negative consequences for humans and the environment. In this study, a pilot-scale trickle-bed reactor for biological methanation and various scale-up scenarios for 2024 and 2050 were investigated using life cycle assessment. A best- and worst-case scenario for technology development until 2050 was evolved using cross-consistency analysis and a morphological field, based on which the data for the ecological models were determined. The results show that the plant scale-up has a very positive effect on the ecological consequences of methanation. In the best-case scenario, the values are a factor of 23–780 lower than those of the actual plant today. A hot-spot analysis showed that electrolysis operation has an especially large impact on total emissions. The final Monte Carlo simulation shows that the technology is likely to achieve a low global warming potential with a median of 104.0 kg CO2-eq/MWh CH4 and thus can contribute to decarbonization.

The increased demand for resources and energy that is developing with rising global consumption represents a key challenge for our generation. Biogas production can contribute to sustainable energy production and closing nutrient cycles using organic residues or as part of a utilization cascade in the case of energy crops. Compared to hydrogen (H2), biogas with a high methane (CH4) content can be fed into the gas grid without restrictions. For this purpose, the CH4 content of the biogas must be increased from 52 to 60% after anaerobic digestion to more than 96%. In this study, biological hydrogen methanation (BHM) in trickling-bed reactors (TBR) is used to upgrade biogas. Design of experiments (DoE) is used to determine the optimal process parameters. The performance of the reactors is stable under all given conditions, reaching a "low" gas grid quality of over 90%. The highest CH4 content of 95.626 ± 0.563% is achieved at 55 °C and 4 bar, with a methane formation rate (MFR) of 5.111 ± 0.167 m3/(m3·d). The process performance is highly dependent on the H2:CO2 ratio in the educts, which should be as close as possible to the stochiometric ratio of 4. In conclusion, BHM is a viable approach to upgrade biogas to biomethane quality and can contribute to a sustainable energy grid. [ABSTRACT FROM AUTHOR]

Syngas, a mixture of CO, H 2 , and CO 2 , is produced by waste carbonaceous feedstocks gasification, which plays an important role in renewable energy production. This study investigated the biomethanation of syngas (45% H 2 , 30% CO, 25% CO 2) in a trickle-bed reactor operated under mesophilic (35 °C), hyper-mesophilic (45 °C), and thermophilic conditions (55 °C). The results revealed that CH 4 production increased with increasing temperature. CH 4 production under steady-state conditions at the hyper-mesophilic and thermophilic temperatures were comparable; 92.2 ± 1.7 mmol/(L bed ∙d) and 93.9 ± 0.9 mmol/(L bed ∙d), respectively. On the contrary, electron losses in volatile fatty acids were the highest under mesophilic conditions. Additionally, digestate can be dosed as a nutrient addition and as a continuous inoculum source to ensure the optimal syngas biomethanation performance. The hyper-mesophilic conditions strategy illustrates possible energy savings for bioreactor heating with CH 4 production comparable to thermophilic conditions, thus saving operating costs. [ABSTRACT FROM AUTHOR]

The increased demand for resources and energy that is developing with rising global consumption represents a key challenge for our generation. Biogas production can contribute to sustainable energy production and closing nutrient cycles using organic residues or as part of a utilization cascade in the case of energy crops. Compared to hydrogen (H2), biogas with a high methane (CH4) content can be fed into the gas grid without restrictions. For this purpose, the CH4 content of the biogas must be increased from 52 to 60% after anaerobic digestion to more than 96%. In this study, biological hydrogen methanation (BHM) in trickling-bed reactors (TBR) is used to upgrade biogas. Design of experiments (DoE) is used to determine the optimal process parameters. The performance of the reactors is stable under all given conditions, reaching a “low” gas grid quality of over 90%. The highest CH4 content of 95.626 ± 0.563% is achieved at 55 °C and 4 bar, with a methane formation rate (MFR) of 5.111 ± 0.167 m3/(m3·d). The process performance is highly dependent on the H2:CO2 ratio in the educts, which should be as close as possible to the stochiometric ratio of 4. In conclusion, BHM is a viable approach to upgrade biogas to biomethane quality and can contribute to a sustainable energy grid.

A dynamic, plug-flow, one-dimensional, and heterogeneous mathematical model for a trickle-bed reactor is described and used to simulate the catalytic hydrocracking of non-edible vegetable oil with countercurrent operation mode. The reactor model considers the hydrocracking reaction of triglycerides towards renewable fuels, which is present in the hydrotreatment process of vegetable oils. The dynamic model was first validated using experimental data reported in the literature, which were obtained in an isothermal micro-scale reactor with cocurrent downflow during hydrocracking of Jatropha oil over a commercial CoMo catalyst. Then, the three-phase reactor model was applied to predict the dynamic behavior of an industrial hydrocracking reactor in order to gain some insight into the transient behavior of the liquid molar concentration, partial pressure, and temperature profiles, which were obtained and discussed as a function of time and axial position of the catalytic bed. The simulations obtained with the proposed dynamic model showed good agreement with the experimental data and trends previously reported for the operation variables profiles at steady-state and relevant findings at industrial scale were obtained. One of the main challenges to produce biofuels by vegetable oils hydroprocessing is to control the high-temperature gradients along the catalyst bed because of the high reaction heat released; therefore, the development of dynamic trickle-bed reactor models, as shown in this work, can be used as a tool to predict the operational behavior of the unit under different reaction conditions and layouts to found the best scheme to control the effects by high-temperature rise. [ABSTRACT FROM AUTHOR]

In this work, fatty acid methyl esters (FAME), as biodiesel components, were continuously produced via the heterogeneously catalyzed transesterification of palm oil with methanol vapor in a countercurrent-flow trickle-bed reactor. Dolomitic rock was used as natural calcium source in the preparation of the calcium oxide-based extrudate catalyst via a physical mixing method. Effects of operating parameters on the FAME yield and the two-phase flow behavior were investigated. The reaction system was characterized by a high mass diffusion resistance at gas-liquid-solid interfaces due to the low solubility of methanol in triglycerides and the high viscosity of oil. Mixing palm oil with commercial grade methyl decanoate, a C10 methyl ester (C10 CME), at a 1:1 mass ratio during the start-up period promoted FAME production. The FAME yield was enhanced by increasing the operating temperature and the methanol flow rate, while operation at a high oil flow rate severely decreased the FAME yield. The concentration of C10 CME, which acted as an emulsifier, in the catalyst bed was crucial to maintain the FAME production stability. In addition to a high FAME yield (ca. 92.3 wt%), the system provided glycerol, obtained without any washing, at a high purity of 93.6 wt%. Image 1 • Palm biodiesel was stably produced via methanolysis in a trickle bed reactor. • Reaction was catalyzed using an extrudate catalyst prepared from dolomite. • The system facilitated the FAME–glycerol separation and methanol recovery. • Adding C10 CME during the start-up period reduced mass diffusion resistance. • The glycerol obtained without any washing had a high purity (93.6 wt%). [ABSTRACT FROM AUTHOR]

Continuous‐flow synthesis of baclofen precursor (2) was achieved using achiral and chiral heterogeneous catalysts in high yield with high enantioselectivity. The key steps are chiral calcium‐catalyzed asymmetric 1,4‐addition of a malonate to a nitroalkene and chemoselective reduction of a nitro compound to the corresponding amino compound by using molecular hydrogen. A dimethylpolysilane (DMPS)‐modified platinum catalyst supported on activated carbon (AC) and calcium phosphate (CP) has been developed that has remarkable activity for the selective hydrogenation of nitro compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • Biological methanation at pilot-scale results in excessive metabolic heat production. • Gas flow directions and volumes impact reactor dynamics. • Trickle-bed moisture content supports thermal stability. • Self-regulation of methanogenic activity by heat stress at 78–83 °C. • Metabolic heat management is critical for technology upscaling. Conversion of electrical energy and CO 2 to a chemical energy carrier in the form of biomethane, can be carried out through the process chain of biomethanation. Although this process provides a promising source of fossil-free natural gas, limited experience with upscaling still hampers its industrial maturation. Through methanation of raw biogas in a 225 L pilot-scale trickle-bed reactor by use of electrolysis-derived H 2, this work uniquely elucidates how metabolic heat from the exothermic biomethanation process present both a challenge and opportunity for upscaling the biomethanation technology. For the first time, a trickle-bed reactor subject to periodic trickling is characterised based on axial temperature profiles as a result of exothermic heat release, in up-flow and down-flow gas configurations. At maximum, reactor core temperatures in the upper thermophilic range (78 and 83 °C) were recorded in certain axial locations, respectively, for substrate gas flow rates of 3.0 and 7.5 NL CO2 /L reactor /d. During a long-term continuous period at 3.0 NL CO2 /L reactor /d, biomethane production with a CH 4 content of ≥95 vol% was measured, in both the reactor's up-flow and down-flow gas configurations. The alternating flow directions and periodic trickling affected both hydrodynamic factors and thermal stability, showing the importance of preheating and humidifying gaseous feed streams and the implementation of a metabolic heat management strategy, by way of cooling, to provide thermal and reaction stability for future upscaling of trickle-bed biomethanation reactors for biological power-to-gas. [ABSTRACT FROM AUTHOR]

For every nine tons of produced biodiesel, there is another ton of glycerol as a byproduct. Therefore, glycerol prices dropped significantly worldwide in recent years; the more significant biodiesel production is, the more glycerol exists as a byproduct. glycerol prices also impact the biodiesel manufacturing business, as it could be sold according to its refinement grade. The primary objective of this work was to evaluate the economic potential of the production of 1,2-propanediol derived from the biodiesel produced in Colombia. A plant to produce 1,2-propanediol via catalytic hydrogenation of glycerol in a trickle-bed reactor was designed. The plant comprised a reaction scheme where non-converted excess hydrogen was recycled, and the heat generated in the reactor was recovered. The reactor effluent was sent to a separation train where 98% m/m purity 1,2-propanediol was attained. Capital and operational costs were estimated from the process simulation. The net present value (NPV) and the modified internal return rate (MIRR) of the plant were used to assess the viability of the process. Their sensitivity to key input variables was evaluated to find the viability limits of the project. The economic potential of the 1,2-propanediol was calculated in USD 1.2/kg; for the base case, the NPV and the MIRR were USD 54.805 million and 22.56%, respectively, showing that, for moderate variations in products and raw material prices, the process is economically viable.

In this work, a model for a trickle-bed reactor for catalytic hydrotreating (HDT) of oil fractions is developed and simulations are performed to investigate its behavior. The model considers dynamic, one-dimensional plug-flow to describe a heterogeneous, adiabatic trickle-bed reactor. It takes into consideration the main reactions present in the HDT process: hydrodesulfurization (HDS), hydrodenitrogenation (HDN), and hydrodearomatization (HDA) with a reconstructed petroleum feedstock using a practical approach of generation of pseudo-components by dividing the boiling point curves of the feedstock. The model is solved using the method of lines with a finite difference scheme for discretization in the axial direction and simulations are performed for an industrial hydrotreating unit to evaluate the behavior of the system under different conditions and assumptions e. g. related to the linear gas velocity. A study of the dynamics is carried out to investigate the behavior of the system with a change in the sulfur compound concentration of the feed. In addition, a sensitivity analysis of the most relevant model parameters is performed. [ABSTRACT FROM AUTHOR]

The complete saturation of commercial olefin-containing (3.3 mol%) C4 stream over Pd/γ-Al2O3 catalysts was studied. The catalysts were prepared by wet impregnation of the support using acidified PdCl2 solutions. The effect of different preparation parameters such as HCl/PdCl2 ratio in impregnation solution, impregnation time and solution volume on palladium distribution and catalytic performance was investigated. The catalysts were characterized by N2 adsorption/desorption, ICP measurements, X-ray diffraction, temperature programmed desorption of ammonia (NH3-TPD) and scanning electron microscopy. Catalytic performance tests were carried out in a three-phase co-current trickle-bed reactor at 50 °C, 27 bar and high olefin conversions in accordance with industrial operating conditions. The catalysts showed different palladium distributions according to preparation procedure. The best performance was observed for egg-shell catalysts prepared by employing short impregnation times (5–10 min) and low competitor levels (HCl/PdCl2 = 2.2 mol mol−1) in impregnation solution. The catalyst lifetime was found to correlate with its activity which was explained by a parallel deactivation mechanism. [ABSTRACT FROM AUTHOR]

Hydrodynamics and (catalytic & non-catalytic) reaction [high-pressure hydrodesulfurization; Fischer-Tropsch synthesis; CO2-monoethanolamine (MEA) absorption; simultaneous CO2 and H2S absorption in MEA; CO2 thermal desorption, enzymatic CO2 hydration] performances of trickle-bed and packed-bed column reactors subjected to static inclination, rolling (symmetrical/asymmetrical externally-generated reactor oscillations) and heaving motions were analyzed via detailed dynamic 3-D models which couple the macroscopic volume-averaged momentum, mass, energy and species balance equations in the liquid/gas phases with diffusion/chemical reaction inside the catalyst particles, enzyme washcoat or liquid film near the gas-liquid interface. Axial symmetry breakdown once the packed bed systems become inclined inflicts noticeable reductions of the reactor (or scrubber) performances. Only the performance of Fischer-Tropsch synthesis in the presence of water-gas shift reaction increases slightly with the increase of trickle-bed reactor inclination because of facile uptake of reactants in the key reactions from the gas phase while a fraction of valuable CO can be forwarded in water gas-shift reaction. For most of the reactions examined, the reactor performance is negatively impacted in asymmetric oscillating multiphase reactors with Fischer-Tropsch synthesis as an exception owing to the presence of water-gas shift reaction the performance of which is slightly improved. This performance deterioration/enhancement is maximal for the reactor moving between vertical and an inclined position when the time-dependent performance waves develop around the steady-state solution of the mid-inclination angle. The oscillatory reactor performance moves towards the steady-state solution of the vertical state when the asymmetry between the two inclined positions dwindles. Symmetric oscillating and heaving trickle-bed and packed-bed column reactors generate an oscillatory performance around the steady-state solution of vertical state which is affected by the amplitude and period of the angular and heaving motions of the vessel. [ABSTRACT FROM AUTHOR]

[Display omitted] • Eulerian multifluid simulations of gas–liquid flow in trickle beds. • Validation using measurements of local liquid spreading, pressure drop and overall liquid hold-up. • Analysis of contributions of different forces governing local liquid distribution. • Effect of flow rates and liquid properties on local liquid distribution. We performed Eulerian simulations of gas–liquid flow in a Trickle Bed Reactor (TBR) to understand contributions of gas–liquid, gas–solid and liquid–solid interaction forces (F → G L , F → G S , F → L S), capillary-pressure (F → C) and mechanical-dispersion (F → D) forces to local liquid spreading and how their contributions change with changes in flow rates and physical properties. Further, we simulated effects of these parameters on pressure drop (Δ P), overall liquid hold-up (〈 ε L 〉) and importantly on local liquid spreading and validated the predictions using measurements. We have shown that F → L S significantly contributes to local liquid spreading, Δ P and 〈 ε L 〉 , whereas F → D contributes marginally. The modified F → L S model led to satisfactory predictions of local liquid spreading, Δ P and 〈 ε L 〉 for a wide range of fluid flow rates and physical properties and predictions are in a satisfactory agreement with the measurements. The present work is an important step in extending the CFD model for simulating reactions and heat effects in TBRs. [ABSTRACT FROM AUTHOR]

Hydrodynamic data obtained from laboratory‐scale trickle‐beds often fail to accurately represent industrial‐scale systems with high packing aspect ratios and column‐to‐particle diameter ratios. In this study, pressure drop, liquid holdup, and flow regime transition were investigated in a pilot‐scale trickle‐bed column of 33 cm ID and 2.45 m bed height packed with 1.6 mm × 8.4 ± 1.4 mm cylindrical extrudates for air‐water mass superficial velocities of 0.0023 – 0.094 kg/m2s and 4.5 – 45 kg/m2s, respectively, at atmospheric pressure. Significant deviation was observed from pressure drop and liquid holdup correlations at low liquid flows rates, corresponding to gravity‐driven flow limit. Likewise, liquid saturation is overestimated by correlations at high liquid flow rates, owing to significantly reduced wall effects. Lastly, trickle‐to‐dispersed bubble flow and trickle‐to‐pulsing flow regime transitions are reported using a combination of visual observations and analysis of the magnitude of local pressure fluctuations within the column. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2560–2569, 2018 [ABSTRACT FROM AUTHOR]

In this study, two series of TiO 2 polymorphs (anatase (A and A1), rutile (R and R1), brookite (B and B1)) and nanocomposite mixtures of TiO 2 polymorphs (anatase A/rutile R (AR), anatase A/TiO 2 -B polymorph (ATB), anatase A1/rutile R1/brookite B1 (ARB)) were synthesized and tested in the process of catalytic wet air oxidation (CWAO). The goal was total removal of the endocrine-disrupting chemical bisphenol A and its intermediates from a model aqueous solution. TiO 2 polymorphs A1, B1 and R1 were prepared with a similar synthesis procedure and from the same TiO 2 precursor to investigate the influence of catalyst preparation on their performance. To discover which is the main driving property of the catalyst that enables enhanced BPA degradation and mineralization in the CWAO process, different surface, textural and morphological characterization techniques (XRD, SEM, UV–vis-DRS, FT-IR, TG and N 2 sorption) were used. CHNS elemental analysis was applied to reveal which of catalysts is suitable for use in a long-term CWAO process. Characterization and catalytic tests of solids examined show that the key factor enabling enhanced activity in the CWAO process is high BET specific surface area of the catalysts. It was found that low specific surface area of a solid can be compensated either by the presence of an appropriate crystallinity, or improved charge separation. Catalysts A, A1 and ATB showed encouraging results of BPA degradation and mineralization in the CWAO process and would also be appropriate for long-term use, since negligibly small amounts of carbonaceous deposits were accumulated on the surface of these solids during tests performed in the period of 40 h. [ABSTRACT FROM AUTHOR]

Power-to-Methane as one part of Power-to-Gas has been recognized globally as one of the key elements for the transition towards a sustainable energy system. While plants that produce methane catalytically have been in operation for a long time, biological methanation has just reached industrial pilot scale and near-term commercial application. The growing importance of the biological method is reflected by an increasing number of scientific articles describing novel approaches to improve this technology. However, these studies are difficult to compare because they lack a coherent nomenclature. In this article, we present a comprehensive set of parameters allowing the characterization and comparison of various biological methanation processes. To identify relevant parameters needed for a proper description of this technology, we summarized existing literature and defined system boundaries for Power-to-Methane process steps. On this basis, we derive system parameters providing information on the methanation system, its performance, the biology and cost aspects. As a result, three different standards are provided as a blueprint matrix for use in academia and industry applicable to both, biological and catalytic methanation. Hence, this review attempts to set the standards for a comprehensive description of biological and chemical methanation processes.

While kinetics is independent of either scale or configuration of hydrotreating reactor, hydrodynamics of reactor depend on both. The hydrodynamics of reactor which comprise of phase mass-transfer, catalyst wetting and pressure drop affect its performance significantly and should be addressed adequately while deciding on configuration or scale up issues. This study evaluates and compares the performance of different configurations of commercial VGO hydrotreater by employing mathematical model encompassing kinetics and hydrodynamics. Two configurations have been studied: • Conventional trickle-bed reactor, subdivided into (a) beds in parallel and (b) beds in series. • Pre-saturated one liquid flow (POLF) reactor, subdivided into (a) reactor with single pre-saturator (POLF-SP) and (b) multiple reactors in series with intermittent pre-saturators (POLF-MP). The performance of conventional reactor in series/parallel is found to be superior to POLF configurations. The inferior performance of POLF configurations is attributed to mixed flow behaviour due to recycle as against plug flow behaviour in conventional trickle-bed reactors. [ABSTRACT FROM AUTHOR]

• CO 2 removal via enhanced weathering (EW) of minerals with seawater was studied. • Two reactor models were extended to allow consistent comparison. • Multi-objective optimization was efficiently assisted by surrogate modelling. • Packed bubble column was shown to clearly outperform trickle-bed reactor. • Forsterite weathering was more challenging than calcite for CO2 removal. Reactor-based enhanced weathering of minerals represents one of the options for CO 2 removal from the atmosphere to control the concentration of greenhouse gases for stabilising the climate. Earlier studies have modelled two reactor types, namely trickle-bed reactor and packed bubble column. However, their CO 2 removal potential has not been compared. Building on the previous studies, this work further develops the mechanistic reactor models to enable them to consistently describe continuous weathering of minerals using seawater. Addressing the computational demands of the mechanistic models, a surrogate modelling-based optimisation procedure is developed to allow each reactor type to be rigorously optimised for minimising two competing objectives, namely energy consumption and space requirement. This has allowed the Pareto fronts of the two reactor types to be produced and compared. When applied to calcite weathering which is predominantly controlled by gas–liquid mass transfer, the packed-bubble column has been shown to consistently outperform the trickle-bed reactor, thanks to its superior mass transfer performance. However, when considering the weathering of forsterite, packed-bubble column performance is significantly worsened compared to calcite weathering, primarily because its low dissolution rate shifts the controlling mechanism of the process from gas/liquid mass transfer to solid dissolution. These results provide new insights to inform the future evaluation of reactor-based enhanced weathering schemes in terms of reactor design selection and the implication of mineral types. [ABSTRACT FROM AUTHOR]

This work aims to investigate the effect of the amount of platinum loading on the hydrogenation of polycyclic aromatic hydrocarbons (PAHs) included in pyrolysis fuel oil (PFO) over Pt/γ-Al 2 O 3 catalysts for the production of jet fuel. Catalyst characterizations were conducted by means of nitrogen adsorption, temperature-programmed desorption of ammonia, and temperature-programmed reduction under a hydrogen flow. The catalytic performance of bead-type Pt/γ-Al 2 O 3 catalysts during the hydrogenation of PAHs included in PFO-cut was evaluated in a trickle-bed reactor. The main components produced by the hydrogenation reaction are decalin derivatives, alkylated cyclohexane, hexahydroindan derivatives, and bicyclohexyl. The cracking reaction was accelerated at the same time as the hydrogenation reaction over the Pt(1.0 wt%)/γ-Al 2 O 3 and Pt(2.0 wt%)/γ-Al 2 O 3 ; hence, the carbon number distribution shifted to the lighter side. The Pt(1.0 wt%)/γ-Al 2 O 3 catalyst showed the highest activity during the hydrogenation of PFO-cut, which is attributed not only to the highest mesoporosity but also to the highest Pt dispersion. Catalyst deactivation could be ignored over the Pt(1.0 wt%)/γ-Al 2 O 3 catalyst during ten hours of time-on-stream. The optimal reaction temperature and space velocity of PFO-cut to maximize the conversion of PAHs were determined to be 300 °C and 1.0 h−1, respectively. [Display omitted] • Bead-type Pt/γ-Al 2 O 3 catalysts were produced by means of impregnation method. • Bead-type Pt/γ-Al 2 O 3 catalysts were applied to hydrogenation of pyrolysis fuel oil(PFO). • Hydrogenation of pyrolysis fuel oil was carried out in a trickle-bed reactor. • The Pt(1.0 wt%)/γ-Al 2 O 3 catalyst showed the highest activity in hydrogenation of PFO. • The reaction conditions were optimized to maximize the yield of cycloalkanes. [ABSTRACT FROM AUTHOR]