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By a reaction of trimethylphosphine with an open‐[60]fullerene, corresponding dimers could be generated via two‐fold deoxygenation processes even though the formation of β‐oxo‐phosphorous ylide is inevitable, a part of which is hydrolyzed to yield an α‐methylene carbonyl derivative. Nevertheless, Wittig reaction and aldol condensation did not proceed well, indicating the presence of an unknown dimerization pathway. In the ylide formation, 1‐phosphonium‐3‐carbabetaine was previously proposed as a key intermediate. Upon assuming that the betaine also participates in the dimerization process, we examined a possible reaction pathway computationally. As the results, the betaine formed by a reaction with the first phosphine was suggested to undergo nucleophilic addition to an unreacted molecule of the open‐[60]fullerene, yielding an epoxide dimer which is then deoxygenated by the second phosphine to furnish the desired open‐[60]fullerene dimer. [ABSTRACT FROM AUTHOR]

The hydrogenation reaction of succinic acid in the liquid phase was studied using the supported metal catalysts, Fe/CeO2, Cu/CeO2, and Fe-Cu/CeO2. The CeO2 support was prepared by precipitation method and the supported metal solids by dry impregnation of support. For monometallic solids, a percentage of iron and copper of 10 wt.%, respectively, was considered. For the bimetallic solid, the metal content was 5 wt.% of each metal. The catalysts were characterized using atomic absorption spectroscopy, X-ray diffraction, nitrogen physisorption, and infrared spectroscopy techniques. The evaluation of the catalytic activity showed that the catalysts favor the formation of γ-hydroxybutyric acid (GHB), with the Cu/CeO2 system presenting the highest percentages of conversion of succinic acid and yield towards GHB. This catalytic behavior could be related to the smaller crystallite size and the greater surface area evidenced in the material compared to the other catalysts studied. Furthermore, the results obtained using the bimetallic material evidenced the role of iron as a promoter for obtaining γ-butyrolactone (GBL). [ABSTRACT FROM AUTHOR]

• Ni clusters/nanoparticles were redistributed to form smaller dispersed nickel species during CO2 hydrogenation. • Dispersed nickel species can partially fill mesoporous pores of silica support. • Redistribution lead to a decreasing trend of both CO2 conversion and CH4 selectivity over 1% Ni/SiO2 with reaction progress. • This anti-sintering phenomenon could be related to the presence of H2. The CO 2 catalytic hydrogenation represents a promising approach for gas-phase CO 2 utilization in a direct manner. Due to its excellent hydrogenation ability, nickel has been widely studied and has shown good activities in CO 2 hydrogenation reactions, in addition to its high availability and low price. However, Ni-based catalysts are prone to sintering under elevated temperatures, leading to unstable catalytic performance. In the present study, various characterization techniques were employed to study the structural evolution of Ni/SiO 2 during CO 2 hydrogenation. An anti-sintering phenomenon is observed for both 9% Ni/SiO 2 and 1% Ni/SiO 2 during CO 2 hydrogenation at 400°C. Results revealed that Ni species were re-dispersed into smaller-sized nanoparticles and formed Ni0 active species. While interestingly, this anti-sintering phenomenon leads to distinct outcomes for two catalysts, with a gradual increase in both reactivity and CH 4 selectivity for 9% Ni/SiO 2 presumably due to the formation of abundant surface Ni° from redispersion, while an apparent decreasing trend of CH 4 selectivity for 1% Ni/SiO 2 sample, presumably due to the formation of ultra-small nanoparticles that diffuse and partially filled the mesoporous pores of the silica support over time. Finally, the redispersion phenomenon was found relevant to the H 2 gas in the reaction environment and enhanced as the H 2 concentration increased. This finding is believed to provide in-depth insights into the structural evolution of Ni-based catalysts and product selectivity control in CO 2 hydrogenation reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

• Ru-Na 2 CO 3 -CaO/Al 2 O 3 DFMs for CO 2 adsorption and hydrogenation to CH 4 are synthesized. • DFMs are subjected to different calcination protocols in static or dynamic streams. • The calcination atmosphere influences the DFM physicochemical properties. • Calcination under N 2 stream accommodates better the adsorbent and Ru phases. • RuNaCa-N 2 is most efficient for CH 4 production (449 µmol g−1 at 370°C) with high selectivity. Integrated CO 2 capture and utilization (ICCU) technology requires dual functional materials (DFMs) to carry out the process in a single reaction system. The influence of the calcination atmosphere on efficiency of 4% Ru-8% Na 2 CO 3 -8% CaO/γ-Al 2 O 3 DFM is studied. The adsorbent precursors are first co-impregnated onto alumina and calcined in air. Then, Ru precursor is impregnated and four aliquotes are subjected to different calcination protocols: static air in muffle or under different mixtures (10% H 2 /N 2 , 50% H 2 /N 2 and N 2) streams. Samples are characterized by XRD, N 2 adsorption-desorption, H 2 chemisorption, TEM, XPS, H 2 -TPD, H 2 -TPR, CO 2 -TPD and TPSR. The catalytic behavior is evaluated, in cycles of CO 2 adsorption and hydrogenation to CH 4 , and temporal evolution of reactants and products concentrations is analyzed. The calcination atmosphere influences the physicochemical properties and, ultimately, activity of DFMs. Characterization data and catalytic performance discover the acccomodation of Ru nanoparticles disposition and basic sites is mostly influencing the catalytic activity. DFM calcined under N 2 flow (RuNaCa-N 2) shows the highest CH 4 production (449 µmol/g at 370°C), because a well-controlled decomposition of precursors which favors the better accomodation of adsorbent and Ru phases, maximizing the specific surface area, the Ru-basic sites interface and the participation of different basic sites in the CO 2 methanation reaction. Thus, the calcination in a N 2 flow is revealed as the optimal calcination protocol to achieve highly efficient DFM for integrated CO 2 adsorption and hydrogenation applications. [Display omitted] [ABSTRACT FROM AUTHOR]

CO 2 hydrogenation to methanol has become one of the most promising ways for CO 2 utilization, however, the CO 2 conversion rate and methanol selectivity of this reaction still need to be improved for industrial application. Here we investigated the structure-activity relationship for CO 2 conversion to methanol of In 2 O 3 -based catalysts by modulating morphology and decorating Au. Three different Au/In 2 O 3 catalysts were prepared, their activity follow the sequence of Au/In 2 O 3 -nanosphere (Au/In 2 O 3 -NS) > Au/In 2 O 3 -nanoplate (Au/In 2 O 3 -NP) > Au/In 2 O 3 -hollow microsphere (Au/In 2 O 3 -HM). Au/In 2 O 3 -NS exhibited the best performance with good CO 2 conversion of 12.7%, high methanol selectivity of 59.8%, and large space time yield of 0.32 g CH 3 OH /(hr·g cat) at 300°C. The high performance of Au/In 2 O 3 -NS was considered as the presence of Au. It contributes to the creation of more surface oxygen vacancies, which further promoted the CO 2 adsorption and facilitated CO 2 activation to form the formate intermediates towards methanol. This work clearly suggests that the activity of In 2 O 3 catalyst can be effective enhanced by structure engineering and Au decorating. [ABSTRACT FROM AUTHOR]

In 2 O 3 has been found a promising application in CO 2 hydrogenation to methanol, which is beneficial to the utilization of CO 2. The oxygen vacancy (O v) site is identified as the catalytic active center of this reaction. However, there remains a great challenge to understand the relations between the state of oxygen species in In 2 O 3 and the catalytic performance for CO 2 hydrogenation to methanol. In the present work, we compare the properties of multiple In 2 O 3 and Ir-promoted In 2 O 3 (Ir-In 2 O 3) catalysts with different Ir loadings and after being pretreated under different reduction temperatures. The CO 2 conversion rate of Ir-In 2 O 3 is more promoted than that of pure In 2 O 3. With only a small amount of Ir loading, the highly dispersed Ir species on In 2 O 3 increase the concentration of O v sites and enhance the activity. By finely tuning the catalyst structure, Ir-In 2 O 3 with an Ir loading of 0.16 wt.% and pre-reduction treatment under 300°C exhibits the highest methanol yield of 146 mg CH3OH /(g cat ·hr). Characterizations of Raman, electron paramagnetic resonance, X-ray photoelectron spectroscopy, CO 2 -temperature programmed desorption and CO 2 -pulse adsorption for the catalysts confirm that more O v sites can be generated under higher reduction temperature, which will induce a facile CO 2 adsorption and desorption cycle. Higher performance for methanol production requires an adequate dynamic balance among the surface oxygen atoms and vacancies, which guides us to find more suitable conditions for catalyst pretreatment and reaction. [ABSTRACT FROM AUTHOR]

Although single-atom Cu sites exhibit high efficiency in CO2 hydrogenation to methanol, they are prone to forming Cu nanoparticles due to reduction and aggregation under reaction conditions, especially at high temperatures. Herein, single-atom Cu sites stabilized by adjacent Na+ ions have been successfully constructed within a metal–organic framework (MOF)-based catalyst, namely MOF-808-NaCu. It is found that the electrostatic interaction between the Na+ and Hδ− species plays a pivotal role in upholding the atomic dispersion of Cu in MOF-808-NaCu during CO2 hydrogenation, even at temperatures of up to 275°C. This exceptional stabilization effect endows the catalyst with excellent activity (306 g·kgcat−1·h−1), high selectivity to methanol (93%) and long-term stability at elevated reaction temperatures, far surpassing the counterpart in the absence of Na+ (denoted as MOF-808-Cu). This work develops an effective strategy for the fabrication of stable single-atom sites for advanced catalysis by creating an alkali-decorated microenvironment in close proximity. [ABSTRACT FROM AUTHOR]

The utilization of carbon dioxide is critical to realize the objective of "carbon peak and neutrality". Among various carbon dioxide exploitation approaches, catalytic hydrogenation of carbon dioxide is a significant method to selectively convert the CO 2 into methanol and other valuable chemicals. Among these products, methanol is a crucial chemical feedstock that can be utilized as a platform molecule for the synthesis of chemicals and fuels as well as a fuel for internal combustion engines and fuel cells, causing particular interest. Nowadays, Catalytic hydrogenation of carbon dioxide into methanol has shifted its focus on the creation of low-cost, environmentally friendly, and efficient catalysts. Inspired of this, we have concluded the mechanism of catalytic hydrogenation of carbon dioxide, and reviewed the research progress of multiple heterogeneous catalysts with high catalytic application prospect, especially the supported catalysts. [ABSTRACT FROM AUTHOR]

To investigate the gas-phase hydrogenation processes of large, astronomically relevant cationic polycyclic aromatic hydrocarbon (PAH) molecules under the interstellar environments, the ion–molecule collision reaction between six PAH cations and H-atoms is studied. The experimental results show that the hydrogenated PAH cations are efficiently formed, and no even–odd hydrogenated mass patterns are observed in the hydrogenation processes. The structure of newly formed hydrogenated PAH cations and the bonding energy for the hydrogenation reaction pathways are investigated with quantum theoretical calculations. The exothermic energy for each reaction pathway is relatively high, and the competition between hydrogenation and dehydrogenation is confirmed. From the theoretical calculation, the bonding ability plays an important role in the gas-phase hydrogenation processes. The factors that affect the hydrogenation chemical reactivity are discussed, including the effect of carbon skeleton structure, the side-edged structure, the molecular size, the five- and six-membered C-ring structure, the bay region structure, and the neighbouring hydrogenation. The infrared spectra of hydrogenated PAH cations are also calculated. These results we obtain once again validate the complexity of hydrogenated PAH molecules, and provide the direction for the simulations and observations under the co-evolution interstellar chemistry network. We infer that if we do not consider other chemical evolution processes (e.g. photoevolution), then the hydrogenation states and forms of PAH compounds are intricate and complex in the interstellar medium. [ABSTRACT FROM AUTHOR]

A series of bimetallic NixCuy catalysts with different metal molar ratios, supported on nitric acid modified rice husk-based porous carbon (RHPC), were prepared using a simple impregnation method for the liquid-phase hydrogenation of furfural (FFA) to tetrahydrofurfuryl alcohol (THFA). The Ni2Cu1/RHPC catalyst, with an average metal particle size of 9.3 nm, exhibits excellent catalytic performance for the selective hydrogenation of FFA to THFA. The 100% conversion of FFA and the 99% selectivity to THFA were obtained under mild reaction conditions (50 °C, 1 MPa, 1 h), using water as a green reaction solvent. The synergistic effect of NiCu alloy ensures the high catalytic activity. The acid sites and oxygen-containing functional groups on the surface of the modified RHPC can enhance the selectivity of THFA. The Ni2Cu1/RHPC catalyst offers good cyclability and regenerability. The current work proposes a simple method for preparing an NiCu bimetallic catalyst. The catalyst exhibits excellent performance in the catalytic hydrogenation of furfural to tetrahydrofurfuryl alcohol, which broadens the application of non-noble metal bimetallic nanocatalysts in the catalytic hydrogenation of furfural. [ABSTRACT FROM AUTHOR]

Photocatalytic conversion of renewable biomass‐derived aldehydes into high‐valued chemicals is a promising path to meet the growing demand for clean energy and chemical resources. However, the approach still faces challenges, such as limited reaction types and low utilization rates due to the complex functional groups and involved polytropic reaction. In the present work, we developed a catalyst of Pt nanoparticles (Pt NPs) supported on a NiO–In2O3 bimetallic oxide (denoted as Pt/NiInOx) for photocatalytic hydrogenation of furfural (FAL) to furfural alcohol (FOL). Owing to the excellent band structure and efficient internal charge transfer on the p–n heterojunction in the catalyst, the highest 99.9% yield to FOL was obtained over the Pt/NiInOx under a light‐emitting diode (LED) light at low temperatures as 273 K. The combination of ·H dissociated from H2 and oxygen vacancy work synergically to adsorb, activate, and converse C=O to the C–O group. The photocatalytic system presents a highly efficient approach for the rapid hydrogenation of biomass‐based aldehydes under a low LED light radiation intensity at a low temperature. The work is expected to serve as an important reference in constructing bimetallic oxide‐supported active metals, enabling efficient separation of photogenerated electrons and holes, and offering oxygen vacancies in various photocatalytic reactions. [ABSTRACT FROM AUTHOR]

Objective The aim is to test the feasibility of using a DPC catalyst to directly conduct catalytic cracking of inferior vacuum residue in industrial units and to explore the impact of blending a certain proportion of inferior vacuum residue on product structure, mainly low-carbon olefin production. Methods The industrial test was carried out by using a 1.2 Mt/a catalytic cracking unit. The study investigated changes in process operations and product structure through adjustments in DPC catalyst inventory proportion and raw material slag blending ratios. Results The industrial practice of using a DPC catalyst to produce olefins from vacuum residue directly showed that when the DPC catalyst inventory proportion reached 26.5%. The blending proportion of vacuum residue in the feed was increased to 15.25%, and the ethylene volume fraction in the catalytic dry gas reached 16.57%, an increase of 2.46 percentage points compared to the blank calibration value. The yields of propylene and triene(ethylene, propylene and 1,3-butadiene) in liquefied gas reached 7.35% and 8.38%, respectively, which increased by 0.67 percentage points and 0.83 percentage points compared with the blank calibration value, monthly efficiency increase could reach 19.639 2 million yuan. Conclusions The DPC catalyst is capable of facilitating the directly catalytic cracking of inferior vacuum residue, offering a streamlined processing flow and significant economic benefits. It can provide new ideas for enterprises to reduce costs, increase efficiency, save energy and reduce carbon. [ABSTRACT FROM AUTHOR]

By utilizing greenhouse gas CO2 and renewable energy-sourced H2 to produce methanol, the "methanol economy" can replace fossil fuels and H2 as the energy storage medium, which not only reduces CO2 emissions, but also mitigates the energy shortage issue. However, the traditional Cu-based catalysts for CO2-to-methanol conversion suffer from low activity at low temperature and high vulnerability to sintering and deactivation. In this contribution, rapidly quenched skeletal Cu catalysts (RQ Cu) are prepared by leaching the RQ Cu–Al alloy with NaOH aqueous solutions of different concentrations. It is found that high NaOH concentration of 10 wt% favors the preparation of the RQ Cu-10 catalyst with higher porosity, lower residual Al content, and larger active Cu surface area (SCu) than the RQ Cu-3 catalyst leached with 3 wt% of NaOH solution. However, in aqueous-phase CO2 hydrogenation at 473 K and 4.0 MPa, the CO2 conversion over the RQ Cu-3 catalyst is more than two times greater than that over the RQ Cu-10 catalyst, and the selectivity and productivity of methanol are 1.20 and 2.69 times of the corresponding values over the RQ Cu-10 catalyst. At 5.0 MPa, the selectivity and productivity of methanol are further boosted to 97.9% and 1.329 mmol gCu–1 h–1 on the RQ Cu-3 catalyst. It is identified that the SCu of the RQ Cu-3 catalyst is well preserved after reaction, while dramatic growth of the Cu crystallites occurs for the RQ Cu-10 catalyst. The better catalytic performance and stability of the RQ Cu-3 catalyst are tentatively attributed to the presence of more residual Al species by using NaOH solution with lower concentration for Al leaching, which acts as the dispersant for the Cu crystallites during the reaction. [ABSTRACT FROM AUTHOR]

A series of Cu-ZnO-ZrO2 (CCZ) catalysts were prepared by the solvothermal method with different solvothermal times (1 h, 3 h, 6 h, and 12 h). The physicochemical properties of these catalysts and the catalytic performance for CO2 hydrogenation to methanol were studied. The highest methanol yield was achieved when the solvothermal time was 6 h (CCZ-6). Furthermore, we found that the copper surface area (SCu) increases and then decreases with an increase in the solvothermal time and that there is a strong correlation between the methanol yield and the SCu. This research highlights the crucial influence of the solvothermal time on the structure and catalytic behavior of Cu-ZnO-ZrO2 catalysts, providing a valuable reference for the development of efficient catalysts. [ABSTRACT FROM AUTHOR]

The efficient hydrogenation of N-heterocycles with H2 under mild conditions remains a significant challenge. In this work, polyphosphazene (PZs) microspheres, novel organic–inorganic hybrid materials possessing unique –P=N– structural units and a diverse range of side groups, were used to serve as support for the design of a stable and efficient Pd nanocatalyst (Pd/PZs). The PZs microspheres were prepared by self-assembly induced by precipitation polymerization, and Pd nanoparticles were grown and loaded on the support by a chemical reduction process. Several characterization techniques, including XRD, FTIR, SEM, TEM, XPS, BET and TGA, were used to study the structural features of the nanocomposites. The results revealed that Pd nanoparticles were uniformly distributed on the PZs microspheres, with primary sizes ranging from 4 to 9 nm based on the abundance of functional P/N/O groups in PZs. Remarkably high catalytic activity and stability were observed for the hydrogenation of quinoline compounds using the Pd/PZs nanocatalyst under mild conditions. Rates of 98.9% quinoline conversion and 98.5% 1,2,3,4-tetrahydroquinoline selectivity could be achieved at a low H2 pressure (1.5 bar) and temperature (40 °C). A possible reaction mechanism for quinoline hydrogenation over Pd/PZs was proposed. This work presents an innovative approach utilizing a Pd-based nanocatalyst for highly efficient multifunctional hydrogenation. [ABSTRACT FROM AUTHOR]

The paper presents an analysis of tests carried out on a titanium plate of a heat exchanger in which the flowing medium was hot gases with a temperature of 110 °C and a pH of less than 1. Strong hydrogenation of the titanium plate caused by the corrosion of the adjacent steel frame plate was detected. As a result of the synergy of the hydrogenation and erosion, a relative reduction in the thickness of the plate was observed locally by up to 94% in relation to the thickness of the titanium plate in the area not affected by degradation. The results of this study are not only of key engineering importance with regard to equipment design and the prevention of mechanical failures in titanium heat exchangers, but also with regard to equipment in other industries. [ABSTRACT FROM AUTHOR]

Catalytic conversion of CO2 to methanol with H2 from renewable energy has attracted increasing interest as a promising strategy for reducing excessive CO2 emissions. However, the performance of reported various catalysts still suffers from low methanol yield with a passable CO2 conversion. In this work, Cu–ZnO–La2O3 interfaces are constructed with various La2O3 mole ratio. Compared to Cu/ZnO, the optimized catalyst (i.e., Cu0.6Zn0.2La0.4) exhibits a much higher mass-specific methanol formation rate (159.3 gMeOH/kgcat/h) at 240 °C and 3 MPa. A series of ex-situ and in-situ characterizations, such as X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), N2O titration measurements, and in-situ diffuse reflectance Fourier transform infrared spectroscopy (in-situ DRIFTS) study, are used to investigate its structure and mechanism study. The dispersion of Cu over Cu/ZnO/La2O3 catalyst is significantly enhanced, forming more Cu–ZnO–La2O3 interfaces. LaOx species favor CO2 activation and generate more carbon intermediates species for CO2 hydrogenation. Furthermore, more Cu+ is bonded, which stabilizes the key intermediate, inhibits its desorption, and facilitates its further hydrogenation to methanol. This work is expected to offer an effective strategy to develop new catalysts with high performance for CO2 hydrogenation to methanol. [ABSTRACT FROM AUTHOR]

In this study, the promoting effects of ruthenium, palladium, and copper on the performance of a 15%Co-1%K/SiO2 catalyst were evaluated during CO2 hydrogenation in a fixed-bed reactor. Reactions were carried out at atmospheric pressure and 270 °C with H2/CO2 ratio of 3. All catalysts were characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) and temperature-programmed reduction (TPR). Ruthenium, palladium and copper facilitated the reduction of cobalt oxides and increased cobalt dispersion. In terms of catalyst's performance, ruthenium addition led to increased CO2 conversion and methane selectivity with a detrimental effect on C5+ hydrocarbons. Palladium also presented a similar pattern at lower loading but a drop in CO2 conversion and increased reverse water–gas shift activity were observed at 3 wt % Pd loading. Promoting with copper resulted in decreased activity, methane selectivity and C5+ hydrocarbons productivity with a much higher CO selectivity. [ABSTRACT FROM AUTHOR]

Fatty alcohols can be generated by hydrogenating fatty acid methyl ester (FAME) using a heterogeneous catalyst. Among diverse alternatives, precious metal-based catalysts such as Re/Nb2O5 and Re/Al2O3 have exhibited superior performance. However, the kinetic study of hydrogenation FAME employing a Rhenium-based catalyst (Re) has not been investigated. Notably, kinetic studies are crucial for performance improvement and reactor design. As a result, the kinetics of the FAME hydrogenation process over these catalysts were studied and modeled comprehensively. The results demonstrate that the reaction with the Re/Nb2O5 catalyst has an order of 0.77 to FAME and 1.48 to hydrogen gas, with an Arrhenius constant of 18.55 bar−1.48 M0.23 min−1 and an activation energy of 64.44 kJ mol−1. The Re/Al2O3 catalyst has an order of 0.67 to FAME and 1.15 to hydrogen, with an Arrhenius constant of 1057.89 bar−1.15 M0.33 min−1 and an activation energy of 78.32 kJ mol−1. The Re/Al2O3 catalyst is more sensitive to temperature changes than the Re/Nb2O5 catalyst. Meanwhile, the Re/Nb2O5 catalyst is more sensitive to pressure changes than the Re/Al2O3 catalyst. [ABSTRACT FROM AUTHOR]

Carbon-supported single-atom catalysts were found to suffer reversible deactivation in catalytic hydrogenation, but the mechanism is still unclear. Herein, nitro compounds hydrogenation catalyzed by N-doped carbon-supported Co single atom (Co1/NC) was taken as a model to uncover the mechanism of the reversible deactivation phenomenon. Co1/NC exhibited moderate adsorption towards the substrate molecules (i.e., nitro compounds or related intermediates), which could be strengthened by the confinement effect from the porous structure. Consequently, substrate molecules tend to accumulate within the pore channel, especially micropores that host Co1, making it difficult for the reactants to access the active sites and finally leading to their deactivation. The situation could be even worse when the substrate molecules possess a large size. Nevertheless, the catalytic activity of Co1/NC could be restored via a simple thermal treatment, which could remove the adsorbates within the pore channel, hence releasing active sites that were originally inaccessible to reactants. [ABSTRACT FROM AUTHOR]

Precisely tuning bicomponent intimacy during reactions by traditional methods remains a formidable challenge in the fabrication of highly active and stable catalysts because of the difficulty in constructing well‐defined catalytic systems and the occurrence of agglomeration during assembly. To overcome these limitations, a PtRuPNiO@TiOx catalyst on a Ti plate was prepared by ultrasound‐assisted low‐voltage plasma electrolysis. This method involves the oxidation of pure Ti metal and co‐reduction of strong metals at 3000°C, followed by sonochemical ultrasonication under ambient conditions in an aqueous solution. The intimacy of the bimetals in PtRuPNiO@TiOx is tuned, and the metal nanoparticles are uniformly distributed on the porous titania coating via strong metal‒support interactions by leveraging the instantaneous high‐energy input from the plasma discharge and ultrasonic irradiation. The intimacy of PtRuPNiO@TiOx increases the electron density on the Pt surface. Consequently, the paired sites exhibit a high hydrogen evolution reaction activity (an overpotential of 220 mV at a current density of 10 mA cm−2 and Tafel slope of 186 mV dec−1), excellent activity in the hydrogenation of 4‐nitrophenol with a robust stability for up to 20 cycles, and the ability to contrast stated catalysts without ultrasonication and plasma electrolysis. This study facilitates industrially important reactions through synergistic chemical interactions. [ABSTRACT FROM AUTHOR]

The Elastic Catalytic Foam-bed Reactor (EcFR) technology was used to enhance a model catalytic hydrogenation reaction by improving gas–liquid mass transfer. This advanced technology is based on a column packed with a commercial elastomeric polyurethane open-cell foam, which also acts as a catalyst support. A simple and efficient crankshaft-inspired system applied in situ compression/relaxation movements to the foam bed. For the first time, the catalytic support parameters (i.e., porosity, tortuosity, characteristic length, etc.) underwent cyclic and controlled changes over time. These dynamic cycles have made it possible to intensify the transfer of gas to liquid at a constant energy level. The application chosen was the selective hydrogenation of phenylacetylene to styrene in an alcoholic solution using a palladium-based catalyst under hydrogen bubble conditions. The conversion observed with this EcFR at 1 Hz as cycle frequency was compared with that observed with a conventional Fixed Catalytic Foam-bed Reactor (FcFR). [ABSTRACT FROM AUTHOR]

An alloy based on the Laves phase, which hydrogenated at room temperature, and magnesium powder were used to create the composite material. Using the method of hydrogen dispersion, the alloy was crushed into a powder with a size of 30 μm. Composite materials were obtained by mixing magnesium with a size of 100 μm and the resulting powders from the alloy for 8 h, followed by pressing. This made it possible to obtain a new type of materials for hydrogen batteries, since they cannot be produced by the traditional casting method, because they do not have mutual solubility. [ABSTRACT FROM AUTHOR]

This study examines the utilization of process optimization as a viable strategy for addressing the issue of global warming through the conversion of carbon dioxide into methanol. In the realm of computational chemistry, the response surface methodology approach has evolved as an alternative for optimizing the reaction parameters through the utilization of statistical models. In the present study, promoted copper/zinc oxide/alumina catalyst was used for carbon dioxide conversion to methanol. The primary objective of the study was to enhance the overall methanol yield by optimizing the various factors in the methanol synthesis. This was accomplished by employing a combination of response surface methodology and one factor at a time techniques. The creation of statistical models was used to optimize the essential factors, and subsequently, one factor at a time. This helps in determining the optimum pressure, temperature, and hydrogen/carbon dioxide molar ratio. Impregnation technique was employed for the synthesis of promoted copper/zinc oxide/alumina catalyst. The analysis of variance results suggested the reduced quadratic model for carbon dioxide conversion, methanol selectivity and methanol yield as responses. The optimum process operating conditions were found to be the hydrogen/carbon dioxide ratio of 10, temperature of 300 °C, pressure of 31 bar and gas hourly space velocity of 2160 mL/g h, in which 28.6% carbon dioxide conversion, 59.2% methanol selectivity and 16.4% methanol yield were achieved. The catalytic performance was then investigated for high pressure range of 40 -- 80 bar with other conditions were fixed at optimal value. The carbon dioxide conversion and methanol selectivity were found to increase with increasing pressure. The highest catalytic performance was achieved at 80 bar with carbon dioxide conversion of 68.35%, methanol selectivity of 93%, and methanol yield of 63.57%. [ABSTRACT FROM AUTHOR]

The rising amount of greenhouse gases has been contributing to global warming and, subsequently, climate change. Industries such as refineries and power plants emit a significant amount of CO2 into the atmosphere. It is imperative to curb anthropogenic CO2 emissions, and hence, in this effort, we explore the utilization of a refinery emission stream to produce value‐added chemicals. The chosen emission stream for the said purpose is a typical flue gas stream from refineries. Following the capture step, this CO2 stream has been leveraged for subsequent valorization processes. Two strategies have been proposed in this paper to valorize the captured carbon dioxide. The first strategy employs the tri‐reforming process with a refinery‐specific fuel gas stream as the co‐reactant. The resulting syngas from tri‐reforming has been converted to chemicals such as methanol (MET) and ethanol. Furthermore, to improve the amount of CO2 valorized, another approach with green hydrogen has been considered. The second strategy aims at direct hydrogenation of the captured CO2 stream to produce MET and ethanol. The proposed strategies analyze the feasibility of valorizing captured CO2 from flue gas to MET and ethanol in terms of gross margin per feed and percentage of CO2 valorization. The performance assessment and analysis of the proposed processes have been carried out using simulations in Aspen Plus® that exhibited up to 74% valorization of CO2 into valuable chemicals. [ABSTRACT FROM AUTHOR]

As an important technology in fine chemical production, the selective hydrogenation of α,β-unsaturated aldehydes has attracted much attention in recent years. In the process of α,β-unsaturated aldehyde hydrogenation, a conjugated system is formed between >C=C< and >C=O, leading to hydrogenation at both ends of the conjugated system, which competes with each other and results in more complex products. Therefore, improving the reaction selectivity is also difficult in industrial fields. Recently, many researchers have reported that surface-active sites on catalysts play a crucial role in α,β-unsaturated aldehyde hydrogenation. This review attempts to summarize recent advances in understanding the effects of surface-active sites (SASs) over metal catalysts for enhancing the process of hydrogenation. The construction strategies and roles of SASs for hydrogenation catalysts are summarized. Particular attention has been given to the adsorption configuration and transformation mechanism of α,β-unsaturated aldehydes on catalysts, which contributes to understanding the relationship between SASs and hydrogenation activity. In addition, recent advances in metal-supported catalysts for the selective hydrogenation of α,β-unsaturated aldehydes to understand the role of SASs in hydrogenation are briefly reviewed. Finally, the opportunities and challenges will be highlighted for the future development of the precise construction of SASs. [ABSTRACT FROM AUTHOR]

Herein, we prepared Pd nanoparticle (NP) catalysts using XC-72 carbon supports through a tailored deposition–precipitation method. Our primary objective was to unravel the size effects of Pd NPs on hydrogenation of tetraacetyldibenzylhexaazaisowurtzitane (TADBIW), a pivotal intermediate for synthesis of high energy density materials hexanitrohexaazaisowurtzitane (CL-20). The controlled modulation of Pd NP size ranged from a mere 1.8 nm to 7.4 nm. Remarkably, our investigations into TADBIW hydrogenation unveiled a fascinating trend: the ultrasmall-sized Pd NPs with a diameter of 1.8 nm exhibited excellent yield and reaction rates. In stark contrast, their larger-sized counterparts demonstrated diminished catalytic activities. To disclose the size-dependent nature, various characterization techniques were employed, including XRD, TEM, XPS, CO and H2 pulse chemisorption. The comprehensive analysis revealed that the ultrasmall-sized Pd possessed more positively charged sites and exhibited higher dispersion. This unique configuration facilitated an accelerated adsorption of hydrogen and the electron-rich substrate TADBIW. Notably, this phenomenon led to a reduction in the activation energy through a thermodynamic effect, thereby enhancing overall catalytic performance. Our results strongly suggested that the ultrasmall-sized Pd NPs can exert a dominated influence on the physical and chemical states of the active sites, playing a key role in triggering the adsorption and activation of the substrate TADBIW. These findings not only deepen our understanding of the intricate connections between Pd NP size and catalytic activity but also open new avenues for advancing the design and optimization of catalysts in the hydrodebenzylation methodologies and synthesis of related compounds. [ABSTRACT FROM AUTHOR]

A series of low-cost α-Ni(OH)2/SiO2 catalysts were successfully fabricated by the vapor-induced internal hydrolysis method, then the hydrogenation of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) was investigated by using the ethanol as the hydrogen donor over these as-prepared α-Ni(OH)2/SiO2 catalysts. Based on the reaction results, these as-prepared catalysts, which could dispense with extra pre-reduction treatment before reactions, exhibited superior catalytic performance for the HMF hydrogenation to BHMF. A remarkable intrinsic selectivity of BHMF selectivity of almost 100% with about 90% HMF conversion could be obtained under 195 °C for 5 h in an N2 atmosphere over the α-Ni(OH)2/SiO2 catalyst of 5-Ni(OH)2/SiO2 with about 5 wt% Ni on SiO2. The almost constant HMF conversion and BHMF intrinsic selectivity found from the recycling tests can indicate that the catalyst was stable without the obvious loss of its catalytic activity after recycling. Moreover, the mechanism of HMF hydrogenation using ethanol over the α-Ni(OH)2/SiO2 catalysts could be referred to as the mechanism of the Meerwein-Ponndorf-Verley reaction. This work will provide a simple synthesis method for future design and development of high-performance, low-cost, and low-energy consumption catalysts for HMF hydrogenation to BHMF. [ABSTRACT FROM AUTHOR]

Tianjin Petrochemical's 1.3 MM TPY wax oil hydrogenation started construction in 2007 and was successfully started in December 2009. In 2016, the fractionation tower was shut down and the fractionation furnace was extinguished. Extinguishing the reaction furnace is a symbol of efficient operation of hydrogenation equipment. Extinguishing the reaction furnace is not only a reflection of energy consumption, but also a technological innovation. At the beginning of 2024, it was planned to shut down the reaction furnace. After the reaction furnace was shut down, due to the fact that the self-produced 1.0 MPa steam was not overheated, it could not be integrated into the 1.0 MPa steam pipeline network directly, and the hydrogen sulfide stripping tower used superheated steam, it was necessary to send the self-produced 1.0 MPa steam to the 0.45 MPa steam pipeline network. Therefore, a new process flow of self-produced 1.0 MPa steam to the 0.45 MPa steam pipeline network was added. The 1.3 MM TPY wax oil hydrogenation unit can reduce fuel gas consumption by 400 m³/h after extinguishing the reaction furnace, achieving an annual efficiency increase of 11 million yuan. Before extinguishing the reaction furnace, it is necessary to conduct feedstock analysis and heat calculation. After extinguishing the reaction furnace, attention should be paid to maintenance to achieve high-quality extinguishing of the reaction furnace. [ABSTRACT FROM AUTHOR]

[Display omitted] A herein proposed PdAu/Al 2 O 3 egg-shell catalyst for selective acetylene hydrogenation combines two factors to provide perfect performance: isolation of Pd 1 active sites by Au and an egg-shell distribution of the active phase across the catalyst pellets. The PdAu/Al 2 O 3 catalyst exhibits high acetylene hydrogenation activity at the level of Pd-catalysts and high intrinsic ethylene selectivity of Au-catalysts. [ABSTRACT FROM AUTHOR]