Hydrogenation Of Acetone Research Articles

Applicability of Graphene Oxide Interlayers in PEMs for Reducing Crossover in Electrochemical Acetone Hydrogenation Reactors

Reactant and product crossover is challenging for proton exchange membrane (PEM)-based electrochemical systems, as it leads to efficiency losses and safety issues. Blocking interlayers can reduce the permeability of PEMs. In this work, a reduction in organic crossover by up to 55% is reached by implementing graphene oxide (GO) flakes in a Nafion membrane for application in an acetone hydrogenation reactor. Additionally, the GO-membrane’s hydrogen crossover is reduced significantly. Those effects are accompanied by an up to 12% increased OCV and scale with the GO interlayer loading. The performance of the MEAs containing GO composite membranes is slightly reduced. This performance loss is traced back to an increased high-frequency resistance (HFR) of the GO composite membranes, the effect of an additional interface resistance resulting from the GO interlayer, and manufacturing-dependent variations in the electrochemically active surface area. Impedance analysis suggests a rearrangement of the GO flakes during operation, reflected by a decreasing HFR and interfacial resistance of the blocking interlayer after the net 15 h lasting electrochemical test protocol. This observation is supported by transmission electron microscopy, which shows structural variations in the GO interlayer at EoT. Nonetheless, the reduction in organic and hydrogen crossover is maintained at EoT.

Influence of Catalyst Surface Structure on the Electrochemical Hydrogenation of Cis,Cis-Muconic Acid

Adipic acid (AA) production from petroleum-based cyclohexane is one of the largest chemical processes in terms of annual volumetric turnover accounting for 3 million tons as of 2022. The current commercial approach to synthesize AA is through the oxidation of petroleum-derived cyclohexane using nitric acid. The release of N2O in stoichiometric amounts makes it one of the most significant greenhouse gas (GhG) emitting processes. The abundance of biomass in the Midwestern United States has driven significant research efforts to synthesize bio-derived and sustainable commodity products and lower the chemical industry’s carbon footprint.1 cis,cis-Muconic acid (ccMA), a biobased C6 diunsaturated diacid platform molecule can be transformed to commodity chemicals like caprolactam, adipic acid, and terephthalic acid, with AA being of particular interest for the synthesis of nylon 6,6.2 For the first time in literature, we demonstrate appreciable production of AA (conversion: 91%, selectivity: >95%) through electrochemical hydrogenation (ECH) of ccMA on PGM catalysts. Carbon-supported palladium (Pd/C) and platinum (Pt/C) selectively produced AA while bulk Pd and Pt yielded the monounsaturated trans-3-hexenedioic acid (t3HDA) intermediate and H2 under all tested conditions. Such an influence of surface structure on the electrochemistry of organics is not unprecedented. Koper et. al3 studied Pt single crystals for the electrochemical hydrogenation of acetone and showed how activity, selectivity, and extent of catalytic poisoning are highly sensitive to the Pt surface structure. Similarly, we used density functional calculations to elucidate the structure-sensitive nature of ccMA ECH and its intermediates by identifying thermodynamically preferred reaction pathways as a function of surface geometry (terrace vs steps). The energetics coupled with experimental observations suggest that the reduction of ccMA to t3HDA occurs through an outer sphere proton-coupled electron transfer mechanism, while the reduction of HDA to AA preferentially occurs on Pd and Pt (111), the most abundant facet in Pd/C and Pt/C. Our calculations also explain the exceptional performance of Pd/C compared to Pt/C by the weaker binding of Pd terrace sites compared to Pt. Overall, combining renewable electricity, in-situ hydrogen generation from water, and a biologically-produced intermediate enabled us to open a sustainable route for bio-adipic acid production. This allows us to further design and optimize the catalyst for the selective production of biobased AA.

Cobaltocene-Mediated Catalytic Hydride Transfer: Strategies for Electrocatalytic Hydrogenation.

The selective electrocatalytic hydrogenation of organics with transition metal hydrides is a promising strategy for electrosynthesis and energy storage. We report the electrocatalytic hydrogenation of acetone with a cyclopentadienone-iridium complex in a tandem electrocatalytic cycle with a cobaltocene mediator. The reductive protonation of cobaltocenium with mild acids generates (C5H5)CoI(C5H6) (CpCoI(CpH)), which functions as an electrocatalytic hydride mediator to deliver a hydride to cationic Ir(III) without generating hydrogen. Electrocatalytic hydride transfer by CpCoI(CpH) to a cationic Ir species leads to the efficient (Faradaic efficiency > 90%) electrohydrogenation of acetone, a valuable hydrogenation target as a liquid organic hydrogen carrier (LOHC). Hydride-transfer mediation presents a powerful strategy to generate metal hydrides that are inaccessible by stepwise electron/proton transfer.

High-entropy oxide-derived Cu catalysts for the coupling reaction of cyclohexanol dehydrogenation with acetone hydrogenation

A reduced Cu0.75Zn0.15Mg7.1Al1Sc1O11-HEO catalyst was highly active and stable for the dehydrogenation of cyclohexanol, and the conversion of cyclohexanol could be evidently enhanced when acetone was used as the solvent and/or hydrogen acceptor.

Boosting acetone hydrogenation at room temperature on Ru-Sn/C catalyst

Carbon supported Ru-Sn bimetallic catalyst shows excellent performance in room-temperature hydrogenation of acetone, 100% acetone conversion with 100% product selectivity to isopropyl alcohol can be achieved within a short reaction time. Catalyst structure-function relationship reveals a synergetic behavior between Ru and Sn sites, demonstrating the essential correlation between Sn/Ru atomic ratio and the resultant variation in catalytic performance. Room temperature hydrogenation of 4-heptanone was also studied, verifying the consistency of the established structure-function relationship in ketones hydrogenation reactions.

Development of a Method and Technique for Analysis of Acetone Hydrogenation Products by Gas Chromatography

Development of a Method and Technique for Analysis of Acetone Hydrogenation Products by Gas Chromatography

Acetone hydrogenation over face-centered cubic and hexagonal close-packed cobalt

Acetone hydrogenation is employed for investigating the structure sensitivity of H2 activation over cobalt catalysts while the produced isopropanol garners increasing interest in the sustainable energy context e.g. as H2 storage material and fuel for direct fuel cells. Both hexagonal close-packed (hcp) and face-centered cubic (fcc) Co can produce isopropanol with 100% selectivity below 150 °C with the reaction proceeding almost ten times faster over hcp Co. Hydrogenation rates are even higher over an hcp Co/Co3O4 composite which remains highly selective to isopropanol despite that Co3O4 yields mostly mesityl oxide and related products. The superior performance of hcp Co and its composite are attributed to efficient generation of atomic H on the metal and the presence of stronger sites for acetone activation on XRD-amorphous phases that are formed during reduction of the Co3O4 precursor at 250 °C and 400 °C. These findings provide insight into the optimum structural design of highly active and selective low-temperature cobalt hydrogenation catalysts.

Development of the Method and Technique to Analyze Acetone Hydrogenation Products by Gas Chromatography

Capillary chromatographic columns with different stationary phases were studied in order to compare their ability to estimate purity of isopropyl alcohol obtained by hydrogenation of acetone. The study was performed with the columns based on polyethylene glycol 20 M terminated with 2-nitroterephthalic acid (PEG20M/FFAP); poly(1-trimethylsilyl-1-propyne) (PTMSP032); and trifluoropropyl (25 %) methyl silicone elastomer (SKTFT 50X). A comparison of the measurement time, asymmetry factors (As) for components of the mixtures, and resolution (Rs) for the pairs of compounds acetone/isopropanol and isopropanol/internal standard gave grounds to choose a capillary column PEG20M/FFAP. A technique was developed for measuring the weight fractions of acetone and isopropanol using the method of internal standard in the gas phase. n-Butanol served as the internal standard. The detection limit was found to be 1.45 for acetone, 1.43 for isopropanol, and 1.28·10–12 g/s for n-butanol. Relative standard deviation (the recurrence factor) did not exceed 4.3 % at a confidence level P = 0.95.

Influence of reduction temperature on Pt–ZrO2 interfaces for the gas-phase hydrogenation of acetone to isopropanol

Pt/ZrO2 reduced at 200 °C offers higher Ov and Pt0 contents, thus leading to excellent acetone hydrogenation activity.

Gas-phase organometallic catalysis in MFM-300(Sc) provided by switchable dynamic metal sites.

MFM-300(Sc) was explored as a catalyst for the gas-phase hydrogenation of acetone. The catalysis results support the presence of non-permanent open Sc(III) sites within the structure due to the requirement of Lewis acid sites for the reaction to proceed. The open Sc(III) sites are generated in situ due to the presence of hemilabile Sc-O bonds. MFM-300(Sc) showed high mechanical and chemical stability, and the crystalline structure was maintained after the catalytic reaction. The catalytic activity of the material was quantified by performing a gas-phase reaction using a continuous flow reactor. The acetone conversion in MFM-300(Sc) was estimated to be 27.7% with no loss of activity after catalytic cycles.

Intensified gas-phase hydrogenation of acetone to isopropanol catalyzed at metal-oxide interfacial sites

The gas-phase acetone hydrogenation to isopropanol is an environmentally benign process relevant to chemical, energy and medical fields, but the catalysts qualified at low temperature and pressure remain challenging. Herein, we show the intensified gas-phase hydrogenation of acetone to isopropanol at metal-oxide interface. The Pt/CeO2 catalyst with highly active and stable Pt-CeO2 interface delivers 92 % acetone conversion with 99 % isopropanol selectivity at 80 °C, weight hourly space velocity of 10 h−1, H2/acetone molar ratio of 2, and 0.1 MPa, and its catalytic performance is preserved during a single-running test of 200 h. A series of electron microscopic, thermal, and spectroscopic analyses testify that acetone could be efficiently adsorbed on oxygen vacancy at Pt-CeO2 interface. The H atoms dissociated by Pt spill over to the interface to hydrogenate the chemically-adsorbed acetone thereon to form isopropanol. Inspired by such observation, the Pt-CeO2 interface was extended to other metal-oxide interfaces (metal: Pt and Ni; oxide: CeO2, TiO2, ZrO2 and Fe3O4), all exhibiting excellent catalytic performance. For example, the Ni/CeO2 could offer 91 % acetone conversion and 99 % isopropanol selectivity, identical to that of Pt/CeO2 under the same conditions. This work particularly investigated the acetone adsorption at the metal-oxide interface, establishing the foundation for rational design of high cost performance catalysts for aldehydes/ketones hydrogenation and other reactions.

Highly Selective Gas-Phase Catalytic Hydrogenation of Acetone to Isopropyl Alcohol

Current industrial synthesis procedures of isopropyl alcohol (IPA), by the direct or indirect hydration of propylene in the gas or liquid phase, suffer from the low conversion of propylene, the requirement for high pressure, and the harmfulness to the environment. In this context, we report a single-step, gas-phase process for the green synthesis of IPA via acetone hydrogenation, in a fixed-bed reactor, under ambient pressure and within a temperature range of 100–350 °C. Composite catalysts with various ratios of ruthenium nanoparticles supported on activated charcoal and nano-zinc oxide (n-Ru/AC/n-ZnO) were used. Catalytic activity and selectivity were functions of n-Ru/AC/n-ZnO loading ratios, reaction temperature, and the hydrogen to acetone molar ratio. The composite catalysts were characterized by X-ray powder diffraction (XRPD), transmission electron microscopy (TEM), hydrogen temperature-programmed reduction (H2-TPR) analysis, and nitrogen physisorption. High yields of IPA were obtained over 3n-Ru/AC/2n-ZnO) catalyst, which showed the highest selectivity of 98.7% toward isopropyl alcohol and acetone conversion of 96.0% under a hydrogen to acetone mole ratio of 1.5 at 100 °C. Reaction rates, calculated from the model equation, were in reasonable agreement with those measured experimentally. The apparent activation energy (Ea) value for acetone hydrogenation was found to be 17.2 kJ/mol. This study proved that immobilized Ru catalysts were potential superior catalysts for the selective hydrogenation of acetone to IPA in exceptionally mild green synthesis conditions.

Process Development for Methyl Isobutyl Ketone Production Using the Low-Pressure One-Step Gas-Phase Selective Hydrogenation of Acetone

Methyl isobutyl ketone (MIBK) is a highly valuable product in the chemical industry. It is widely used as an extracting agent for heavy metals, antibiotics, and lubricating oils. Generally, MIBK can be produced by three-step and one-step liquid-phase methods. These methods are expensive and energy-demanding due to the high pressure and low conversion of acetone. A novel nano-Pd/nano-ZnCr2O4 catalyst was developed to produce MIBK with high conversion and selectivity of 77.3% and 72.1%, respectively, at 350 °C and ambient pressure, eliminating the need for high pressure in conventional MIBK processes. This study is the first that proposes a newly developed process of methyl isobutyl ketone (MIBK) production using the low-pressure one-step gas-phase selective hydrogenation of acetone. In this work, a novel process flow diagram has been developed for the production of MIBK using the developed nano-catalyst. The process was heat integrated, resulting in a 26% and a 19.5% reduction in the heating and cooling utilities, respectively, leading to a 12.6% reduction in the total energy demand. An economic analysis was performed to determine the economic feasibility of the developed process, which shows that the process is highly profitable, in which it reduced both the capital and operating costs of MIBK synthesis and showed a return on investment (ROI) of 29.6% with a payback period of 2.2 years. It was found that the ROI could be increased by 18% when the reactor temperature is increased to 350 °C. In addition, the economic sensitivity analysis showed that the process is highly sensitive to product prices and least sensitive to utility prices, which is due to the versatility of the process that requires only a low amount of energy.

Understanding the electrochemical hydrogenation of acetone on Pt single crystal electrodes

• Pt(1 1 0) electrode is the only basal plane active for the acetone electroreduction. • The inclusion of (1 1 1) steps on (1 1 0) terraces slightly alters the behavior of Pt(1 1 0). • Insertion of (1 0 0) steps on (1 1 0) terraces decreases the activity. • Sulfate competes with acetone for the surface sites. The heterogeneous upgrading of biomass by means of electrocatalytic hydrogenation is an attractive way to refine products for industrial and pharmaceutical purposes. Also, the efficient electrochemical reduction of carbonyl compounds can act as hydrogen vectors, and therefore energy vectors. In this manuscript, we render further fundamental insights into the electrochemical reduction of acetone as a model molecule of carbonyl compounds. The structural sensitivity of the reaction is demonstrated by using platinum single crystal electrodes with low Miller indices and stepped electrodes with (1 1 0) terraces and either (1 1 1) or (1 0 0) monoatomic steps. Among the basal planes, Pt(1 1 0) is the only one active for the electroreduction of acetone. The inclusion of (1 1 1) steps on the (1 1 0) terraces does not significantly alter the behavior of Pt(1 1 0), but increasing the (1 0 0) step density has been observed to decrease the activity. We attribute this different performance to a geometrical effect of the active sites. By using different supporting electrolytes, we have found that sulfate competes with acetone for the surface sites, thus modifying the adlayer interfacial structure and hampering acetone reactivity.

Catalytic Dehydration of Isopropanol to Propylene

Catalytic dehydration of isopropanol to propylene is a common reaction in laboratories to characterize the acid–base properties of catalysts. When acetone is produced, it is the sign of the presence of basic active sites, while propylene is produced on the acid sites. About 2/3rd of the world production of isopropanol is made from propylene, and the other third is made from acetone hydrogenation. Since the surplus acetone available on the market is mainly a coproduct of phenol synthesis, variations in the demand for phenol affect the supply position of acetone and vice versa. High propylene price and low demand for acetone should revive the industrial interest in acetone conversion. In addition, there is an increasing interest in the production of acetone and isopropanol from CO/CO2 via expected more environmentally friendly biochemical conversion routes. To preserve phenol process economics, surplus acetone should be recycled to propylene via the acetone hydrogenation and isopropanol dehydration routes. Some critical impurities present in petrochemical propylene are avoided in the recycling process. In this review, the selection criteria for the isopropanol dehydration catalysts at commercial scale are derived from the patent literature and analyzed with academic literature. The choice of the process conditions, such as pressure, temperature and gas velocity, and the catalysts’ properties such as pore size and acid–base behavior, are critical factors influencing the purity of propylene. Dehydration of isopropanol under pressure facilitates the downstream separation of products and the isolation of propylene to yield a high-purity “polymer grade”. However, it requires to operate at a higher temperature, which is a challenge for the catalyst’s lifetime; whereas operation at near atmospheric pressure, and eventually in a diluted stream, is relevant for applications that would tolerate a lower propylene purity (chemical grade).

Crystal growth and catalytic properties of AgPt and AuPt bimetallic nanostructures under surfactant effect

AgPt and AuPt bimetallic nanostructures offer a highly active catalytic process in acetone hydrogenation reaction to isoproponal. • Sodiumdodecyl sulfate (SDS) promotes anisotropic crystals growth in bimetallic AgPt and AuPt nanostructures. • SDS along with lattice mismatch effects realizes high-energy structure of nanofern in AgPt and large surface area fibrous structure in AuPt. • AgPt and AuPt nanostructures exhibit highly active catalytic properties in acetone hydrogenation reaction. The surface properties of the catalyst, including the surface atom structure and surfactant, determine the charge-transfer process during the catalytic reaction. Here, we present a study on how the surfactants influence the nanocrystal's growth and the catalytic properties of AuPt and AgPt nanoparticles. We found that the surfactant, i.e. sodium dodecyl sulfate (SDS), promotes anisotropic crystal growth in both AuPt and AgPt due to the disruption of symmetrical crystal growth in these fcc crystal and surface passivation processes. Catalytic acetone hydrogenation reaction analysis in the presence of AuPt and AgPt nanocatalyst indicated that the reaction rate was optimized at mild SDS concentration, i.e. 0.1 M, for both AuPt and AgPt nanocatalysts with their turn over frequency of the reaction reached 3363.2 s −1 and 380.2 s −1 , respectively. The AuPt and AgPt nanocatalyst passivated SDS should find extensive use in catalytic hydrogenation reactions.

Economy, Exergy, energy consumption and environmental human toxicity potential assessment of vacuum extractive distillation coupled pervaporation process for separating Acetone/Isopropanol/Water Multi-azeotropes system

Industrial wastewater from the catalytic hydrogenation of acetone to isopropanol contains multi-azeotropes. It is difficult to purify acetone and isopropanol by traditional distillation, and the treatment capacity and potential economic benefits are huge. The process design of the sustainable development of vacuum extractive distillation coupled with pervaporation technology to separate the industrial organic wastewater from ACT hydrogenation to IPA has changed the sequence of separation of the multi-azeotrope system with sustainable development and reduced the energy consumption and energy consumption of the multi-azeotrope separation for resource recovery. The comprehensive economic cost enhances the evaluation of the environmental human toxicity to the wastewater separation and discharge process. Based on the strict design specifications of the chemical system process simulation software, the sequential iterative method is utilized to simulate the design and optimization of the chemical separation process. The EHH2O-EG process achieved a reduction of 7.40% (TAC), 7.51% (energy consumption and GWP), and 7.36% (HTP) compared with the EHEG-H2O process in terms of the economy, exergy, environmental assessment, energy consumption, and human toxicity potential, and EHH2O-EG process is better than EHEG-H2O process. This novel separation process provides a novel idea for process optimization, and is the best designing and separating sustainable process for promoting green chemical wastewater discharge treatment. It has significantly superior instructive for the design of selecting different solvents to separate multi-component azeotropes. The value of this research is investigated competitive and cost-effective in the current chemical industry for the production of rubber additives, bisphenol A and polycarbonate, isopropyl alcohol pharmaceuticals, and cumene to achieve the progressive goal of carbon neutralization.

Process Design of Isopropyl Alcohol Synthesis Section of 80,000 Tons/Yea

Isopropanol is a chemical product with great application value and can be used as a chemical raw material and organic solvent. This design is a synthesis section of 80,000 tons/year isopropanol, using acetone hydrogenation synthesis process. At a temperature of 180 °C, a pressure of 0.8 MPa, n (hydrogen)/n (acetone) = 1.5 : 1, performed in a column tubular fixed bed reactor. This design uses a 4-stage tubular fixed-bed reactor with an effective length of 8.5 m, a total length of 15.705 m, and a housing diameter of 2.9 m. The total number of 4-segment column tubes is 10,444, and the column tubes are made of seamless stainless steel pipes with a diameter of 38 mm and a thickness of 4 mm. The design improves production safety and reduces energy losses. The design results have certain guiding significance for actual production and application.

Development of an efficient Pt/SiO2 catalyst for the transfer hydrogenation from perhydro-dibenzyltoluene to acetone

The storage of hydrogen in liquid organic hydrogen carriers (LOHCs) represents a safe and easy to handle storage solution for energy from renewable sources. Dibenzyltoluene (H0-DBT)/perhydro-dibenzyltoluene (H18-DBT) is a promising LOHC system due to its low flammability, wide liquid range and high storage density for hydrogen. However, this LOHC system requires high temperature heat (typically > 250 °C) for hydrogen release, which lowers the efficiency of the storage cycle if no appropriate source of waste heat is available. This disadvantage can be mitigated by transfer of the hydrogen onto an acceptor molecule such as acetone at mild temperatures, forming isopropanol which can be used as fuel in direct fuel cell concepts or represents a valuable chemical product. Herein, we present the development of an active and selective platinum on silica (Pt/SiO2) catalyst for the transfer hydrogenation of acetone using perhydro-dibenzyltoluene as the sole source of hydrogen. Relevant catalyst design parameters, such as the optimal pore size, Pt loading, reduction and oxidation temperatures/times, are identified and their influence on the catalyst morphology and performance is discussed.

Selective synthesis of MIBK via acetone hydrogenation over Cu-Al mixed oxide catalysts

This work involves direct synthesis of methyl isobutyl ketone (MIBK) using a multifunctional catalyst via vapor phase hydrogenation of acetone at atmospheric pressure. Cu-Al mixed oxide catalysts were prepared from inexpensive precursors by co-precipitation of Cu and Al hydroxides with varying Cu:Al atomic ratio. The catalysts were characterized with N2 physisorption, FESEM (coupled with EDS), CO2/NH3-TPD, H2-TPR, FTIR and XRD. The evaluation of catalyst activity was performed in a continuous tubular reactor. The catalytic reactions were studied from variation of parameters such as temperature (200–300 °C), 0.5–1.25 H2/CH3COCH3 mole ratio and space-time (13.34–21.45 kg cat h/kmol acetone). The mixed oxide with Cu/Al atomic ratio of 0.25 showed highest selectivity (74%) for MIBK at 250 °C. Kinetics of the reaction was studied by varying space-velocity at different temperatures. Rate equations based on L-H-H-W model were validated with the kinetic data obtained at four temperatures. The activation energy was found to be 81 kJ/mol.