Reaction Engineering Research Articles

Selective Hydrogenation Reaction: Utilizing a Microreactor for Continuous Flow Synthesis of Nickel Nanoparticles

Introduction: In this investigation, we employed a continuous flow reactor to synthesize nickel (Ni) nanoparticles exhibiting uniform size distribution and excellent stability. Our focus centered on exploring the impact of reactant dilution and flow rate on the synthesis process. Result: It was observed that the optimization of these parameters played a pivotal role in obtaining small-sized Ni nanoparticles. Specifically, we achieved successful synthesis using a solution of 0.00025 M NiCl2·6H2O and 0.002 M NaBH4, with a flow rate of 25 mL/h. The resulting Ni nanoparticles were effectively coated with the CTAB surfactant, as confirmed through thorough analysis using TEM and PSD techniques. Additionally, the interaction between the surfactant and nanoparticles was verified via FTIR analysis. We subjected them to high-pressure alkene hydrogenation to assess the catalytic activity of the synthesized Ni nanoparticles. Method: Encouragingly, the Ni nanoparticles exhibited excellent performance, producing hydrogenated products with high yields. Moreover, we capitalized on Ni nanoparticles' catalytic effect for synthesizing two natural compounds, brittonin A and dehydrobrittonin A. Remarkably, both compounds were successfully isolated in quantifiable yields. This synthesis protocol boasted several advantages, including low catalyst loading, omission of additives, broad substrate scope, straightforward product separation, and the ability to recover the catalyst up to eight times. In summary, this study effectively showcased the potential of continuous flow reactor technology in synthesizing stable and uniformly distributed nanoparticles. Conclusion: Additionally, it highlighted the effectiveness of Ni nanoparticles as catalysts in various chemical reactions. The findings from this study hold significant implications for developing more efficient and sustainable chemical synthesis protocols.

Comparison of continuous technologies for vegetable oils epoxidation

Epoxidized Vegetable Oils (EVOs) are an important class of chemical compounds obtained from biomass and used as intermediates to produce several bio-products and chemicals, such as hydroxy-alkoxy compounds, diols, amines, and carbonates. Epoxides originating from vegetable oils and their derivatives, namely fatty acids or alkyl esters, are still produced by semibatch technology which suffers from severe mass transfer limitations and long reaction times, thus impairing the final product selectivity and restraining the overall productivity. In this work, two continuous reactor technologies to produce epoxides from vegetable oils were developed and compared. The first configuration, consisting of only one jacketed tubular reactor operated in co-current up-flow mode, showed a good performance at T = 318 K achieving a double bond conversion exceeding 95 % and an epoxide selectivity higher than 90 %. The second technology, where two jacketed tubular reactors connected in series were operated in up-flow mode, gave comparable conversions and selectivity to the previous one, but under somewhat milder conditions, at T = 294 K and 298 K for the first and second reactor, respectively, and in the absence of any added acid catalyst. Following this latter concept, additional experiments were performed in the presence of different vegetable oils as starting materials to confirm the performance with more common feedstocks. Both configurations showed results that clearly exceed the performance of the current semibatch process.

Preliminary Verification of Key Physical Models in Oxide Fuel Performance Analysis Code FEATURE Based on COMSOL

Nuclear performance analysis is of great significance for fuel design optimization and the safe operation of a reactor. Considering the design requirements of the China initiative Accelerator Driven System (CiADS) project, it is necessary to develop relevant fuel performance analysis tools to predict fuel performance evolution during service. The Fuel Element Analysis Tool for Undercritical Reactor Engineering (FEATURE) code, based on the advanced multiphysics coupling platform COMSOL software, is under development in this context, with a current focus on oxide fuel for fast reactors. This paper mainly conducts preliminary comparative verification of the oxygen redistribution, plutonium redistribution, and fission gas release modules of the FEATURE code through model examples, code-to-code evaluation, and experimental data. The results indicate that the FEATURE code exhibits good accuracy and reliability in simulating oxygen and plutonium redistribution, as well as fission gas release, making it suitable for integrated coupling calculations.

Usefulness of insights into the kinetic compensation effects in the kinetic analysis of the coal gasification process

AbstractIn this paper, an attempt has been made to understand the kinetic compensation effects and their usefulness in the kinetic analysis of a lab‐based gasification study. The gasification experiment was carried out in two different gasifying environments, that is, 0.4%O₂ + 8%H₂O‐Ar and 8%H₂O‐Ar, for two different particle sizes of Loy Yang brown coal. Analysis of kinetic values with the change in particle size and gasifying environment was investigated. This provides information on the path of product gas formation and how the overall controlling factor affects the path of char gasification, including the rate‐limiting step. Furthermore, the results indicate that having multiple sets of kinetic parameters caused by the inclusion of the change in char properties into kinetics during solid–gas heterogeneous reactions opens up the scope for wider applications in chemical reaction engineering. This includes the design of a reactor with a proper kinetic model, optimization of feedstock, and process parameters with the identification of pathways for product gas formation, which ultimately plays a key role in scaling up technology from bench‐scale to plant‐scale. In contrast, the study of kinetics with having a single set of kinetic data based on the initial change in char properties limits its applications.

Molybdenum Disulfide Induced Phase Control Synthesis of Multi-dimensional Co3S4-MoS2 Heteronanostructures via Cation Exchange.

Phase control over cation exchange (CE) reactions has emerged as an important approach for the synthesis of nanomaterials (NMs), enabling precise determination of their reactivity and properties. Although factors such as crystal structure and morphology have been studied for the phase engineering of CE reactions in NMs, there remains a lack of systematic investigation to reveal the impact for the factors in heterogeneous materials. Herein, we report a molybdenum disulfide induced phase control method for synthesizing multidimensional Co3S4-MoS2 heteronanostructures (HNs) via cation exchange. MoS2 in parent Cu1.94S-MoS2 HNs are proved to affect the thermodynamics and kinetics of CE reactions, and facilitate the formation of Co3S4-MoS2 HNs with controlled phase. This MoS2 induced phase control method can be extended to other parent HNs with multiple dimensions, which shows its diversity. Further, theoretical calculations demonstrate that Co3S4 (111)/MoS2 (001) exhibits a higher adhesion work, providing further evidence that MoS2 enables phase control in the HNs CE reactions, inducing the generation of novel Co3S4-MoS2 HNs. As a proof-of-concept application for crystal phase- and dimensionality-dependent of cobalt sulfide based HNs, the obtained Co3S4-MoS2 heteronanoplates (HNPls) show remarkable performance in hydrogen evolution reactions (HER) under alkaline media. This synthetic methodology provides a unique design strategy to control the crystal structure and fills the gap in the study of heterogeneous materials on CE reaction over phase engineering that are otherwise inaccessible.

Aluminate 2K systems in digital concrete: Process, design, chemistry, and outlook

Digital concrete is advancing due to growing economic incentives for construction automation. Achieving more sustainable concrete construction requires carbon reduction, and digital concrete technologies enable material-saving designs. By decoupling production strength from design strength, two-component (2K) systems utilizing aluminate precipitation offer the most flexibility, allowing more sustainable mixes with higher substitution levels. However, 2K aluminate systems are complex and demand a deeper understanding of their chemistry and strength buildup. This article reviews the basics of 2K aluminate systems, specifically aluminum sulfate-based and calcium aluminate cement/calcium sulfate-based systems, and their use in an inline active mixing reactor. An example reaction engineering analysis predicts the degree of reaction in a given reactor design, relating it to yield stress. The two chemical systems are compared, and future research recommendations are provided.

Mechanism of the rapid generation of superheated and saturated steam using a water-containing porous material

Superheated steam (SHS) is employed in various fields for everyday activities and industrial production, e.g., drying, cleaning, and reaction engineering. Although a facile method for realizing rapid SHS and saturated steam generation from water-containing porous materials has been proposed, with a second order start-up/cut-off response time and high energy utilization efficiency, the mechanism of this rapid SHS generation has not been clarified despite the proposition of a two-step process, including heating-based evaporation beneath the wire heater and reheating in the flow path. In this study, further experiments were conducted to separately consider both heating processes. The steam temperature directly beneath the wire heater correlated well with the film temperature, which is equal to the average temperature of the wire heater and the saturation temperature of the surface of the porous material. The measurement results of the temperature distribution inside the porous material block as well as the results of the electrical resistance directly beneath the wire heater revealed that no dry-out area was formed directly beneath the wire heater during SHS generation. Further, the three-dimensional laser scanning results revealed significant roughness on the surface of the porous material. The narrow gap, which was formed between the wire heater and the surface of the porous material, was critical to SHS generation, and the detailed mechanism was presented.

(Keynote) Automated / Autonomous Platforms for Synthesis, Purification, and Characterization of Quantum Dots

Controlling composition, structure, and thus properties of nanomaterials continues to be of importance to numerous fields. For example, applications of quantum dots range from displays and bioimaging, to metal nanoparticles for (electro-) catalytic conversions. The vastness of synthesis parameter space, in combination with still limited understanding of the nucleation and growth mechanisms for many quantum dots systems still hampers progress in identifying nanomaterials with desired properties for existing and newly envisioned purposes. Furthermore, the identification of optimal synthesis recipes for these nanostructures remains a major hurdle.This presentation will report on the development and application a number of enabling capabilities for the synthesis and characterization of quantum dots, achieved through reactor engineering. We demonstrate how the use of automated flow reactors not only helps in run-to-run reproducibility but also in uncovering mechanistic information. Examples include reactors with dedicated nucleation, growth, and shell formation zones, and investigation that revealed mechanistic insight of how water concentration affects QD synthesis outcome. We also employed an autonomous flow reactor system to map synthesis parameter space of specific QD systems, a project that relied on fast, fully automated in-situ characterization using UV-vis or photo-luminescence in combination with multi-step machine learning workflows The utility of flow reactors, however, is limited when considering chemistries with longer reaction times. Hence, more recently we developed a fully automated batch reactor for parameter space mapping of QD synthesis via hot injection, the most frequently used method in both QD research and production at scale. This batch platform is being augmented with purification capabilities, to address some of the challenges of in-line, in-situ characterization of raw reaction mixtures, and to enable using advanced optical and structural characterization methods to provide insight into the actual structure of the QD materials.

(Energy Technology Division Research Award) New Materials vs. Reaction Engineering in Anion Exchange Membrane Fuel Cells

In recent years, the desire to design, create and/or discover advanced functional nanomaterials has changed the way that faculty members and graduate students approach engineering research. Though materials can (and likely will) make a significant impact on most technologies, the truth is that in most disciplines, materials with highly complex structures remain on the fringes of realistic deployment. In some cases, even when so-called “advanced” materials are discovered there are significant difficulties in transitioning them from ex-situ tests to the real reacting environment. Therefore, we must be careful to understand that material chemistry and structure are only two variables in an extremely complex system and often times there are other fundamental (e.g. electronic mobility, thermodynamic barriers, diffusivity) and engineering (porosity, concentration, temperature) properties that drive behavior in such environments. Additionally, there are systems where materials are being sought without a clear understanding of what is truly limiting performance and durability or the properties that are required of a real engineered system to operate effectively.Anion exchange membrane fuel cells (AEMFCs) are an example system where the literature is littered with exotic materials that claim to improve activity and stability (presumed as performance and durability in real devices). However, it will be shown that for several years, such new materials had limited success (if any) in advancing performance and durability. This talk will summarize ~five years of work in AEMFCs where the performance and durability of AEMFCs were improved significantly without any new materials – just using traditional chemical engineering principles for reactor engineering. Only later – once device operation was well understood and controlled – were new materials helpful. On the operational side, the main discussion point will be the transport of water. On the materials side, new membranes and catalysts will be discussed. The talk will end with perspectives on transitioning AEMFCs to more realistic operating environments, including the mitigation of effects from CO2.

Efficient Electrochemical Reduction through Flow Cells Using Spherical-Polymer Based Carbon Supported Catalysts as Fixed-Bed Electrode

The transition to economically friendly feedstocks and the electrification of chemical synthesis reactions gained much attention in the recent years. To be able to compete with the conventional processes, it is crucial not only to concentrate on the electrochemical reactions itself but also to constantly improve the reactor concepts. A vast variety of designs are imaginable and already well-described – from a simple, undivided beaker cell setup to a divided flow cell with separate electrolytes at cathode and anode. [1] As electrode material not only flat metal electrodes are studied, but also the concept of using carbon supported metal nanoparticles is well-known to employ high dispersion to lower the total amount of required metal. [2,3] While there are already commercial flow reactors and electrodes available for electrosynthesis with flat standard electrodes, reactors using a fixed-bed of porous carbon with nanodispersed metals as electrode just recently started to attract attention. [4] Dealing with the pressure drop over the catalyst bed, while the electrical contact is still ensured, are key challenges for this reactor design. Spherical polymer-based carbons (SPBC) combine porous carbons properties with a high purity and especially spherical character. [5] While these advantages led already to commercial products for chromatographic applications (e.g. Carboxen®) the potential regarding flow-electrochemistry has not been leveraged. Key developments for this are reproducible synthesis procedures to deposit active metal on the SPBCs and the design of an electrochemical flow cell using these catalysts in a fixed-bed electrode configuration.The first part of this work presents the deposition of Cu through different impregnation and reduction procedures on a SPBC (Carboxen® 1032, 50 µm, Merck). The carbon was characterized by physisorption, TPD-MS, TPO, Raman and SEM. The resulting metal-impregnated carbon catalysts were additionally investigated regarding the metal loading. Using the applied impregnation and reduction parameters targeted metal loadings (3 – 20 wt%) could be well achieved. The second part focuses on the design and commissioning of a flow-cell for the application of the SPBC-supported catalysts as a fixed-bed at the cathode side. Electrochemical synthesis reactions are targeted in the cell and the reduction of 5-HMF to BHMF was chosen as the test reaction in this work. In the framework of the cell development multiple aspects not only regarding the construction but also reaction engineering issues had to be considered: material stability of the pump, fixation and pressure drop of catalyst bed, choice of electrolyte, effect of dissolved oxygen in the catholyte, optimal flow rate, reliable electrochemical protocol and selection of contact material. The latter has to be a compromise between chemical inertness and an enhanced electron transfer between the catalyst bed and the contact material (e.g. soft foil vs. hard metal). Figure 1A shows the current voltage characteristics of two possible contact materials (graphite foil, boron-doped diamond (BDD)) in the targeted electrolyte (0.5M borate buffer with 0.25M potassium chloride). Here, the graphite foil clearly shows a higher activity towards the hydrogen evolution reaction which may result in a less effective electrolysis later on. The comparison of BDD as contact material without and with a catalyst bed (Carboxen® 1032 loaded with 20 wt% Cu) resulted in a significant shift in the current voltage characteristic to lower overpotentials. Therefore, the electronic contact with the carbon bed is clearly enabled and the carbon spheres loaded with copper catalyze the reaction. Figure 1B presents the results of the test reaction with the conversion of the educt 5-HMF as well as the selectivity to the targeted product BHMF over the reaction time with BDD as contact material without and with a fixed bed of Cu/SPBC catalyst. The experiments prove full 5-HMF conversion within 23 h on stream in combination with a high selectivity towards BHMF with the catalyst bed. The mass-based productivity reaches values of up to 1.78 mmol h-1 gCu -1 and is therefore about 15 times higher compared to the use of conventional Cu foil (Pliterature = 0.11 mmol h-1 gCu -1 [6]). It is possible that due to the metal-support approach in the fixed-bed configuration, the copper is leveraged more efficiently and small amounts allow to provide sufficient metal surface area for the catalytic reaction.

Accelerated Development and Optimization of Adiponitrile Production via Kolbe Electrolysis of Biomass-Derived Precursors

Environmental and societal pressures are demanding a transition from fossil-based resources to renewable and sustainable feedstocks for the production of materials. In this context, biomass streams emerge as scalable candidates for creating sustainable chemicals. Electrocatalytic transformation of biomass can facilitate the production of chemicals under mild conditions and can be easily integrated with renewable energy sources. These transformations could lead to the production of sustainable monomers and polymers from biomass, significantly enhancing the sustainability of plastics production. Amongst a large number of plastics manufactured by the chemical industry, Nylon 6,6 is one of the most important fossil-derived polymers for the production of high-performance textiles and structural materials. Central to Nylon 6,6 production is adiponitrile (ADN), predominantly synthesized via energy-intensive thermochemical processes. An alternative route, electrochemical hydrodimerization of acrylonitrile (AN), although successful, still depends on fossil feedstocks. A promising sustainable source for ADN is renewable glutamic acid, derived from hydrolysis of waste proteins.1,2 This process involves transforming glutamic acid to 3-cyanopropanoic acid (CPA) and then to ADN through Kolbe electrolysis, a reaction with a historical background and multiple pathways. Our study utilizes an electrochemical reaction engineering approach to examine the Kolbe electrolysis of CPA to ADN and AN, focusing on a hierarchical research methodology. This approach allowed us to simultaneously accelerate the exploration of numerous reaction parameters while also conducting detailed studies under optimal conditions. This method has enabled us to gain deeper insights into the factors controlling reaction selectivity. We discovered that platinum electrodes favor ADN formation, with selectivity increasing at higher current densities. Optimal CPA concentrations, the presence of larger alkali cations, solvent composition, and controlled pH levels significantly influence ADN production, reducing side reactions such as the oxygen evolution reaction (OER). When using graphite electrodes, an increase in AN production was observed, with the solvent composition playing a crucial role in determining the rate of ADN formation. Our investigation has led to a deeper understanding of the electrochemical conversion of CPA to ADN, revealing key parameters that influence reaction selectivity and rate. The insights obtained from this study are not only pivotal for the specific case of ADN production but also have broader implications for a range of electrochemical decarboxylation reactions. The hierarchical research approach employed here demonstrates its potential for speeding the development of sustainable electrochemical processes. Our insights and methodology used for the electrosynthesis of ADN from biomass-derived feedstocks can be deployed to the deployed to the development of other biomass transformations advancing our ability to produce essential chemicals sustainably.

(Invited) Photoelectrode Design for Photoelectrocatalytic Hydrogen Production

Semiconductor nanomaterials hold the keys for efficient solar energy harvesting and conversion processes like photocatalysis and photoelectrochemical reactions. In this talk, we will give a brief overview of our recent progress in designing semiconductor nanomaterials for photoelectrochemical energy conversion including solar hydrogen generation and low-cost solar cells. In more details, we have been focusing on a few aspects; 1) photocatalysis mechanism, light harvesting, charge separation and transfer and surface reaction engineering of low-cost metal oxide based semiconductors including TiO2, BiVO4 as efficient photoelectrode for photoelectrochemical hydrogen production; 2). The design of ultra-stable composites of perovskite-MOF with improved light emitting and photocatalytic performance.1-5 The resultant material systems exhibited efficient photocatalytic performance and improved power conversion efficiency in solar cells, which underpin sustainable development of solar-energy conversion application. References ： 1. Adv. Mater., 2018, doi:10.1002/adma.201705666.2. Angew. Chem, 2019, doi/10.1002/anie.2018105833. Nature Commun, 2020, (2020) 11:21294. Science, 2021, 374, 621.5. Adv. Mater., 2022, 34 (10), 2106776.

(Invited) Electrochemical Engineering Approaches for High-Performing Electrosynthesis of Polymer Precursors

The chemical industry accounts for ~5% of the US energy utilization and >30% of the US energy-derived industrial CO2 emissions. Amongst these processes, the production of organic chemical commodities, many of which are used as polymer precursors, account for the majority of the energy utilization (>1200 TBTU/y). The electrification of these processes via the implementation of electro-organic reactions could accelerate the decarbonization of the chemical industry, and bring additional sustainability advantages over their thermo-chemical counterparts. Currently, however, two major challenges prevent the deployment of electro-organic reactions: their low selectivity and their low production rates. To circumvent these barriers, our group deploys electrochemical reaction engineering principles to engineer electrode/electrolyte interfaces and design high-performing electro-organic processes. In this presentation, I will discuss how we implement this approach to understand and improve the performance of electro-organic reactions for the production of large-scale precursors for the production of Nylon 6,6 and polyethylene.The production of Nylon 6,6 involves the step-growth polymerization of 1,6-hexanediamine (HMDA) with adipic acid. HMDA is currently produced by the hydrogenation of adiponitrile (ADN). Here, I will present our insights into the electrohydrodimerization of acrylonitrile (AN) to adiponitrile (ADN). This is one of the largest electro-organic reaction deployed in industry and serves as a model process for the development of practical organic electrochemical processes. Our investigations on ADN uncovered relationships between the microenvironment at and near the electrical double layer (EDL) and reaction performance metrics (i.e., selectivity, efficiency, and productivity). I will discuss general guidelines for electrolyte formulation, dynamic electrochemical operation, the implementation of convective forces to mitigate transport limitations, ultimately leading in the conversion of AN to ADN at Faradaic efficiencies >80% and current densities of 100’s mA/cm2. Our learnings on ADN electrosynthesis helped us to engineer the electrocatalytic hydrogenation of ADN to HMDA, achieving the highest reported selectivity to date for this reaction (>95%). I will also show how similar electrochemical engineering approaches allowed us to elucidate factors that control performance in the electrochemical production of ADN from glutamic acid, an abundant and inexpensive bio-based feedstock, and of ethylene from bio-derived propionic acid. Through our studies, we aim to electrify and bring sustainability to chemical manufacturing, one reaction at a time.

Evaluating The Effectiveness of Wastewater Treatment In the Reusable Packaging Industry: A Case Study of ALNER’S WWTP In Indonesia

The widespread use of single-use plastic packaging has become a significant environmental issue, particularly in the Global South. This study examines the innovative approach of the startup Alner, which employs a combination of electrochemical treatment and Moving Bed Biofilm Reactor (MBBR) technology in its wastewater treatment plant (WWTP) to manage wastewater generated from the cleaning of reusable packaging. Wastewater samples were collected before and after treatment, and analyzed for key parameters such as Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD5), Total Suspended Solids (TSS), oil and grease, ammonia, surfactants, and phosphates. The results demonstrated a significant reduction in all measured pollutants, with COD reduced by 99.58% and BOD5 by 99.56%. Post-treatment values for all parameters were well within the regulatory limits set by the Ministry of Environment and Forestry Regulation No. P68/MenLHK/Setjen/Kum.1/8/2016. This study underscores the potential of reuse models in reducing single-use plastic waste and highlights the importance of effective wastewater treatment in maintaining environmental sustainability. Alner's approach provides a scalable and environmentally friendly solution, setting a benchmark for similar initiatives in the industry, and supports the feasibility and sustainability of integrating advanced wastewater treatment technologies in the reusable packaging sector, offering a comprehensive solution to plastic pollution.

Coupling of the best-estimate system code and containment analysis code and its application to TMLB’ accident

With the development of advanced pressurized water reactor technology, the thermal-hydraulic coupling effect between the containment and the primary system becomes increasingly tight. In order to meet the demand for integrated safety analysis between the containment and the primary system, this paper investigates a direct coupling method between the best-estimate system code Advanced Reactor Safety Analysis Code and the containment analysis program ATHROC (Analysis of Thermal Hydraulic Response Of Containment). The feasibility of this direct coupling method and the applicability of the coupled program for overall safety analysis are demonstrated using Marviken two-phase flow release experiments. The ATHROC/ARSAC coupled program is employed to analyze the impact of the pressure relief function of the CPR1000 nuclear power plant pressurizer on the behavior of the primary system and containment during the TMLB’ accident. The calculation results indicate that these measures can reduce the pressure of the primary system to the level acceptable by the low-pressure injection system, but at the same time, they cause the pressure in the containment to rise to nearly 0.4 MPa. Therefore, to ensure the structural integrity of the containment, it is necessary for the non-passive hydrogen recombiner to effectively reduce the hydrogen concentration, thereby avoiding additional pressure increase in the containment due to hydrogen deflagration, which could lead to overpressure failure. The findings of this study are of significant reference value for improving the safety performance of thermal-hydraulic systems in operational Gen-II and advanced Gen-III pressurized water reactor nuclear power plants.

Development of Lead-Cooled Fast Reactor Technologies at ENEA Brasimone Research Center

Development of Lead-Cooled Fast Reactor Technologies at ENEA Brasimone Research Center

Chemical and engineering bases for green H2O2 production and related oxidation and ammoximation of olefins and analogues.

Plastics, fibers and rubber are three mainstream synthetic materials that are essential to our daily lives and contribute significantly to the quality of our lives. The production of the monomers of these synthetic polymers usually involves oxidation or ammoximation reactions of olefins and analogues. However, the utilization of C, O and N atoms in current industrial processes is <80%, which represents the most environmentally polluting processes for the production of basic chemicals. Through innovation and integration of catalytic materials, new reaction pathways, and reaction engineering, the Research Institute of Petroleum Processing, Sinopec Co., Ltd. (RIPP) and its collaborators have developed unique H2O2-centered oxidation/ammoximation technologies for olefins and analogues, which has resulted in a ¥500 billion emerging industry and driven trillions of ¥s' worth of downstream industries. The chemical and engineering bases of the production technologies mainly involve the integration of slurry-bed reactors and microsphere catalysts to enhance H2O2 production, H2O2 propylene/chloropropylene epoxidation for the production of propylene oxide/epichlorohydrin, and integration of H2O2 cyclohexanone ammoximation and membrane separation to innovate the caprolactam production process. This review briefly summarizes the whole process from the acquisition of scientific knowledge to the formation of an industrial production technology by RIPP. Moreover, the scientific frontiers of H2O2 production and related oxidation/ammoximation processes of olefins and analogues are reviewed, and new technological growth points are envisaged, with the aim of maintaining China's standing as a leader in the development of the science and technologies of H2O2 production and utilization.

Improving the Phosphatase-Catalyzed Synthesis of 5′-Nucleotides: A Reaction Engineering Approach

5′-Phosphorylation of nucleosides is a reaction as important in nature and in industry as it is cumbersome to be performed. Whilst chemical phosphorylation relies on the use of harsh reagents, solvents, and conditions, as well as on the need for protection–deprotection steps, biocatalysis can be a tool to achieve one-step phosphorylation reactions, which are selective, protecting group-free, and occurring under mild and sustainable conditions. In this work, the wild-type non-specific acid phosphatase from Morganella morganii (PhoC-Mm) was expressed, purified, and used for the synthesis of inosine 5′-monophosphate (IMP), an important food additive, by using pyrophosphate (PPi) as an inexpensive phosphate donor in a fully aqueous medium at 30 °C. Via the fine-tuning of the reaction set-up taking into account the type of buffer, amount of PPi, mode/time of PPi addition, and enzyme and substrate concentration, PhoC-Mm could be used for catalyzing the phosphorylation of inosine (I) to IMP in a good yield and high purity (62% yield). The catalysis of the hydrolytic reaction direction, which is the primary function of phosphatases in nature, was here reversed to a certain extent by a reaction engineering approach, without the need for protein engineering strategies.

Baseline design of laser fusion research reactor with MW class laser facility

We propose a sub-ignition/burning reactor which is named the Laser-fusion Subcritical Power Reactor Engineering Method (L-Supreme). The reliabilities of L-Supreme in a MW class laser facility are assessed with respect to the following points: a reactor core, a target chamber, a target delivery system, an Exhaust Detritiation System (EDS), and neutron shielding. The Japan Establishment for Power-laser Community Harvest (J-EPoCH) would be applied as a MW class laser facility. A non-cryogenic glass balloon target filled with gaseous deuterium-tritium (DT) is contained in a target capsule. A chain-type magazine system might be used for a mass supply of the target capsules. Each target capsule is delivered to the center of a reactor core at 1 Hz. A batch of 10 000 laser shots would realize 0.22 MJ fusion power. The amount of tritium per batch is 1.51 × 1012 Bq. During laser experiments, unburned tritium is evacuated and transferred into an Exhaust Detritiation System (EDS). An evacuation rate of more than 0.1 m3 s−1 is required in order to recover less than 5000 Bq m−3 of the threshold of tritium concentration within 1 h. For safety, emergency situations such as tritium leakage in facilities are examined. The EDS works by internal circulation processes. Assuming leakage of tritium for a batch, an air circulation flow rate of 4100 Nm3 h−1 is required in an experimental hall for recovering less than 5000 Bq m−3 within 48 h. A primary and secondary neutron shield concept are proposed and would provide full neutron shielding. We conclude that it is possible to construct the L-Supreme system by marshalling current technologies.

Critique: YEASTsim - A Matlab-based simulator for teaching process control in fed-batch yeast fermentations

One of the primary challenges in chemical engineering education lies in the practical application of theoretical knowledge. Contemporary society demands chemical engineers who are not only adept at critical thinking but also proficient in practical problem-solving. Historically, acquiring such practical experience has been heavily dependent on laboratory experiments. However, with the advent of advanced technology, there are now more accessible and varied opportunities for experiential learning. Simulation-based learning tools have proven to be powerful complements to traditional laboratory experiments. These tools enable students to investigate complex chemical processes, test hypotheses, and develop practical skills in a safe, cost-effective, and scalable environment. This critique aims to evaluate the educational potential of the YEASTsim simulator, positioning it as an interactive and innovative tool to enhance the study of core subjects such as Chemical Reaction Engineering, a fundamental component of chemical engineering practice.