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Although research on microbubbles (MBs) has intrigued a lot of researchers, very few studies have been done about the influences of MBs on the free radical formation and also on the degradation rates of organic compounds by ultrasonic irradiation. Here we report the degradation of Acid Orange 7 by the ultrasound irradiation in the solution of MBs for the first time. It was found that acceleration of the degradation rate of Acid Orange 7 was observed only for the 45 kHz ultrasonic irradiation to the microbubble solution. Dependence of gases inside the MBs on the sonochemical efficiencies with the existence of MBs was also measured using the KI method and it was found that the dependence of the sonochemical efficiencies on gases inside the MBs was in the order of Kr > Ar ~ N2 > O2 > He, supporting the conclusions that the observed phenomena were due to the cavitation by the 45 kHz ultrasonic irradiation. The dependences of ultrasonic frequency and power were investigated using various commercially available ultrasonic oscillators, and the influence of the size distribution of microbubbles on the sonochemical efficiencies was further investigated using a flow reactor system with two ultrasound generators. Finally, we showed that the frequency of the ultrasound was more sensitive than the size of microbubbles for the sonochemical enhancement by the 45 kHz ultrasonic irradiation to the solution of MBs and then discussed possible roles of nanobubbles in the presently observed phenomena.

This work aimed to study the fractionation of sugarcane bagasse using a two-step hydrothermal and ethanosolv process in a flow-through reactor system. The effects of reaction temperature with or wi...

In this work, a CaO/CeO2 composite was used in a process that coupled the calcium looping for CO2 capture and CaO/H2O thermochemical heat storage. A four fixed-bed reactor system was used to invest...

Gold nanoparticle (AuNP) formation by applying pulsed discharge plasma in the slug flow reactor system was demonstrated. Experiments were carried out continuously at room temperature. The argon gas as a gas phase and the hydrogen tetrachloroaurate(III) tetra hydrate solution containing lysine as a liquid phase simultaneously flowed in the slug flow reactor system. The flow rates of the feed solution and argon gas were kept at 1.5 and 0.2 mL/min, respectively. To generate discharge plasma, the AC power supply with a bipolar pulsed output at 10 kV was applied. The purple color solution product was obtained, and the ultraviolet–visible (UV–vis) spectrophotometer showed that this possessed the absorption light from 510 to 550 nm associated with the existence of gold nanoparticles in each collected sample. Transmission electron microscopy (TEM) revealed that the lysine-capped AuNPs were produced in a spherical morphology and dispersed in aqueous solution products with a diameter of less than 20 nm.

The kinetics of the synthesis of noncommercially available quantum dot (QD) solvent N-oleoylmorpholine (NOM) was investigated in a semibatch reactor system to enable scale up. Morpholine was inject...

A microchannel electrochemical reactor system was designed to facilitate the reduction of CO2 to CO, which is composed of a premixing section in the upstream consisting of a circular microchannel f...

Spinel-like ZnFe2O4 is tailor-made synthesized for catalyzing CO2 hydrogenation, achieving an ultra-high yield (1858.1 g kgcat-1 h-1) of full spectrum alkenes in a three-stage reactor system. This study provides rational design concepts from catalyst to equipment amelioration by combining promoter regulation and ex situ water removal, efficiently catalyzing CO2 into valuable chemical feedstocks with industrial potential.

An automated continuous flow reactor system equipped with inline analysis, was developed and applied in the self-optimisation of a nanoparticle catalysed reaction. The system was used to optimise the experimental conditions of a gold nanoparticle catalysed 4-nitrophenol reduction reaction, towards maximum conversion in under 2.5 hours. The data obtained from this optimisation was then used to generate a kinetic model, allowing us to predict the outcome of the reaction under different conditions. By combining continuous flow nanoparticle synthesis with this approach, the development timeline for these emerging catalysts could be significantly accelerated.

Hybrid nanoflowers materials have recently received great attention in enzyme immobilization applications because of the advantages such as their large surface area, excellent stability, simple, eco-friendly, and cost-effective synthesis. In this study, l-asparaginase which is an important commercial enzyme in the medicine and food industry was selected as a model enzyme. To the best of our knowledge, this study is the first report of designing L-asparaginase@hybrid nanoflowers to enhance its enzymatic performance. L-asparaginase@hybrid nanoflowers were synthesized using ASNase as an organic component and Cu(II) ion as inorganic component. They were characterized by their morphology and chemical point of view by using different techniques. The synthesized L-asparaginase@hybrid nanoflowers exhibited high residual activity at broad pH and high temperature ranges in comparison to free form. Moreover, L-asparaginase@hybrid nanoflowers possessed good reusability and excellent long-time storage stability. Especially, L-asparaginase@hybrid nanoflowers-3 maintained nearly 51 and 75% of its original activity, respectively, after nine consecutive catalytic cycles and storage at 30 degrees C for 4 weeks. The results indicated that these hybrid nanoflowers will be promising carrier matrix for the immobilization of ASNase in biotechnological applications with improved catalytic properties.

This paper describes the design and experimental validation of a novel flow-through reactor system conceived for experimental studies to determine the kinetics and thermodynamics of mineral precipitation and dissolution in environmental conditions relevant to CO2 geological storage. The experimental system was designed to work under a confining pressure of up to 150 bar, temperature up to 150 °C and corrosive conditions. The unique design allows the injection of precise amounts of liquid CO2 into the reactor while avoiding the formation of multiple CO2 phases. The modular design enables the in-situ measurement of pH using a pressure resistant in-line probe and electronic gauges which record pressure and temperature at multiple points. The system enables the user to withdraw liquid samples without disturbing the experimental conditions in the reactor. Customized computer software was developed and connected to the system to provide automatic data-logging capabilities, remote process control and the ability to partially shut-down the system in case of safety issues.

We propose a new approach for the synthesis of optimal chemical reactor networks based on the concept of elementary process functions [1] and dynamic optimization. This approach is capable of incorporating process intensification options at an early design stage. Only one single differential equation is required to describe the mass balance of the whole reactor system along the reaction route. This equation contains terms describing mass fluxes from outside the reactor system and mass fluxes which flow between different positions of the reaction route. We demonstrate that different reactor types and different reactor connections can be represented by such a formulation. After solving an optimization problem using such a model, optimal profiles of state variables and fluxes are obtained. Based on these profiles, the optimal reactor system is determined. After the presentation of the theoretical background and the derivation of the new approach, it is illustrated in case studies and validated by comparison with literature results. The advantages of this new approach presented in our contribution are its simplicity in description and implementation, universality in representing different reactor types and networks, and the potential to consider different intensification and integration options at an early design stage.

DuPont Water Solutions, a business unit of DuPont Safety & Construction, continues to expand its product portfolio to support the purification and reuse of water. In one way of achieving this, it is adding membrane-based modules, which remove dissolved gases from water, through a partnership that it has formed with Sun Chemical Corp, as this article briefly explains. As an aside, we also report on DuPont's OxyMem Ltd which recently won a ‘Breakthrough Technology Company of the Year’ award for its membrane aerated biofilm reactor system.

Future demand of rice is projected to increase with the increase of global population. However, the presence of bacteria, insects, and fungi has resulted in various changes in the physical and chemical characteristics of rice grain. To make it worse, the overuse of post-harvest chemicals (fungicide and pesticide) has caused possible risks to human health through either occupational or non-occupational exposure. For the last few years, cold plasma has been developed as an alternative non-thermal emerging technology for rice grains treatment due to its ability to inactivate or decontaminate pathogens without causing thermal damage and free of any harmful residues. Therefore, this review describes the operational mechanism of cold plasma treatment technology on rice grains, existing reactor system designs, and parameters influenced by the treatment technology (reactor design parameters and treatment process parameters). Possible advanced investigation on future reactor design modification as well as standard operating range of influenced parameters were suggested for improved efficiency and effectiveness of cold plasma treatment.

In this work, several M x O y -supported CuO-MnO 2 (M x O y = Al 2 O 3 , CeO 2 , TiO 2 and Y 2 O 3 ) composite catalysts were synthesized by the co-impregnation method using copper and manganese acetates as precursors. The catalysts were characterized by N 2 adsorption-desorption at 77 K, XRD, FESEM, FT-IR and XPS techniques. Low-temperature CO oxidation performances of the catalysts were evaluated using a fixed-bed reactor system. Amongst the prepared catalysts, CuO-MnO 2 /CeO 2 exhibited excellent CO oxidation activity, good working stability after about 1 h of reaction tested and superior kinetics performances. The dual synergistic effects in CuO-MnO 2 and CuO-CeO 2 are associated with the enhanced CO oxidation process observed over CuO-MnO 2 /CeO 2 . The catalyst shows promise for removing CO from typical confined spaces such as onboard naval submarines, space-crafts and mine refuge chambers.

Acetylene gas has been applied as a feedstock under transition-metal catalysis and photo-redox conditions to produce important chemicals including terminal alkynes, fulvenes, and fluorinated styrene compounds. The reaction discovery process was accelerated through the use of “stop-flow” micro-tubing reactors. This reactor prototype was developed by joining elements from both continuous micro-flow and conventional batch reactors, which was convenient and effective for gas/liquid reaction screening. Notably, the developed transformations were either inefficient or unsuccessful in conventional batch reactors. Its success relies on the unique advantages provided by this “stop-flow” micro-tubing reactor system.

This work presents the biodegradation of imidacloprid during composting process in a closed reactor. Composting mass was prepared from fresh vegetable waste, tobacco waste, dry leaves, imidacloprid 1.25 mg/kg (dry solids) and bacterial suspension of Pseudomonas aeruginosa FN. The composting process was carried out under forced aeration (0.516 dm3/min/kg) in a column reactor (10 dm3) under adiabatic conditions over 21 days. In a closed reactor system, the intense biodegradation of imidacloprid was during first 7 days when 68% of imidacloprid was degraded. The conversion and rate of biodegradation of imidacloprid in a closed reactor was much higher and faster than in an open pile. Imidacloprid degradation during composting process was described and simulated as first-order process. Degradation constant and half-life of imidacloprid were estimated in a closed reactor (k d = 0.135 ± 0.016 mg/kg/day, t 1/2 = 5.13 days) and in an open pile (k d = 0.025 ± 0.002 mg/kg/day, t 1/2 = 27.88 days).

Innovative reactor concepts show evidence to significantly improve the reaction performance in comparison to conventional reactor systems. To evaluate the reactor concepts, experimental investigati...

Bi-functional catalysts were prepared using HY zeolites with various SiO2/Al2O3 ratios for acidic function, NiW for metallic function, and K for acidity control. 1-Methylnaphthalene was selected as a model compound for multi-ring aromatics in heavy oil, and its selective ring opening reaction was investigated using the prepared bi-functional catalysts with different levels of acidity in a fixed bed reactor system. In NiW/HY catalysts without K addition, the acidity decreased with the SiO2/Al2O3 mole ratio of the HY zeolite. Ni1.1W1.1/HY(12) catalyst showed the highest acidity but slightly lower yields for the selective ring opening than Ni1.1W1.1/HY(30) catalyst. The acidity of the catalyst seemed to play an important role as the active site for the selective ring opening of 1-methylnaphthalene but there should be some optimum catalyst acidity for the reaction. Catalyst acidity could be controlled between Ni1.1W1.1/HY(12) and Ni1.1W1.1/HY(30) by adding a moderate amount of K to Ni1.1W1.1/HY(12) catalyst. K0.3Ni1.1W1.1/HY(12) catalyst should have the optimum acidity for the selective ring opening. The addition of a moderate amount of K to the NiW/HY catalyst must improve the catalytic performance due to the optimization of catalyst acidity.

Future emission standards are becoming increasingly stringent as California will phase in LEV III regulations starting in 2015 and EPA will implement Tier 3 regulations starting in 2017. Current vehicles emit greater than 50% of targeted tailpipe emissions during the first minute or two following “cold-start” mainly due to the ineffectiveness of existing catalytic converters at low temperatures (

We demonstrate biogas upgrading towards full CO2 conversion in mild conditions in a three-step reactor system using Ru- and Ni-based catalysts. In each of the three reactor stages, the temperature is carefully controlled, thus optimizing the reaction thermodynamics and kinetics, resulting in a maximized global CO2 conversion. At ambient pressure, 92% conversion can be achieved over a commercial Ru/Al2O3 catalyst at a space velocity of 2 L/h/gcat in every stage. At 2 bar conversion is enhanced to above 99%. It is possible to substitute the Ru-based catalyst in the first stage with a cheaper Ni-based catalyst, shifting the first-stage temperature to higher values forming also CO. CO has a positive effect on the following step since CO is converted to CH4 in the CO methanation reaction. In this way, it is possible to achieve the same final conversion compared to the Ru-operated reactor system using Ni in the first reactor stage.

A spray reactor system that recycles solvent enables green and rapid synthesis in high yield, at a production rate on the order of multiple grams per hour.

This paper describes the synthesis and characterization of La0.8Sr0.2NiO3 nano-perovskite type catalyst for steam-CO2 reforming (SCR) and CO2 reforming (DR) of methane. Effect of gelation agents such as PVA, EDTA and PAA on nano-perovskite structures was investigated. XRD, H2-TPR and FT-IR analysis were used to characterize the prepared catalysts. The catalytic reaction was performed in a fixed bed reactor system at 1 atm and 800 °C. The feed ratio of CH4:H2O:CO2 as reactants was adjusted according to the SCR and DR reactions. As a result, CH4 and CO2 conversions of PVA agent catalyst were higher than that of PAA and EDTA agent catalyst for DR reaction because the PVA agent catalyst had a well-established perovskite, a high absorption, a high reducibility. However, the PAA agent catalyst had a higher reactivity due to its high interaction of catalysts for SCR of methane due to its strong interaction of catalysts.

Although the NO removal-based air-purification ISO method ISO 22197-1:2007 is well established, its preconditioning requirements mean that only the initial activity of the photocatalyst under test is measured owing to the often-reported, gradual alteration of the surface kinetics for NO oxidation by air through the accumulation of surface HNO 3 . Herein, we compare the photocatalytic NO removal abilities of a number of different, common TiO 2 materials, surface-saturated with photogenerated HNO 3 , with their behaviours observed during the typical 5 h-long ISO standard test. It is found that all the TiO 2 materials studied eventually become largely NO to NO 2 converters after sufficient exposure to NO under irradiation (>5 h) due to the accumulation of surface HNO 3 . The UV exposure time, t *, necessary to reach this HNO 3 saturated condition is different for each different catalyst. As a consequence, an alternative preconditioning process for the ISO method is proposed which can be used to provide a more realistic measure of the photocatalytic activity of the underlying material and provide a measure of the NO x removing capacity of the photocatalytic material under test.

The existing screening and characterization systems for biocatalysts operate in batch mode, which could make catalyst selection and process development inaccurate when continuous operation mode is required in industry. A significant improvement of an innovative screening system based on miniaturized multiple membrane reactors formerly presented by the author is outlined, which enables continuous feeding of substrates and continuous removal of products. Although the presented screening system was originally designed for homogeneous enzymatic reactions, it can be used without further modifications for continuous catalysis with polymer-bound chemical catalysts or for quasi-homogeneous systems like reverse micelles.

In a variety of reactions in the chemical industry, eggshell catalysts with a thin active layer are applied; they are often crushed for laboratory testing. The destruction of the shell can be avoided by a special reactor design. The presented advanced TEMKIN reactor is a further development of the reactor system for testing eggshell catalysts on the laboratory scale published by Temkin and Kul'kova in 1969. It is suitable for kinetic studies and for the detailed investigation of deactivation processes, as shown on the example of selective hydrogenation of acetylene.

In a variety of reactions in the chemical industry egg-shell catalysts with a thin active layer are applied, which are often crushed for laboratory testing. The destruction of the shell can be avoided by a special reactor design. The presented Advanced TEMKIN reactor is a further development of the reactor system for testing egg-shell catalysts in laboratory scale published by Temkin et al. in 1969. It is suitable for kinetic studies as well as for the detailed research of deactivation processes, as is shown on the example of the selective hydrogenation of acetylene.

MnxOy-Na2WO4/SiO2 is an active catalyst for the oxidative coupling of methane, with a remarkable stability and a suitable performance for an industrial application. MnxOy-Na2WO4 was supported on different support materials and the catalytic activity was investigated with a parallel reactor system, allowing a direct comparison of all results. Considering the C2 yield and the potential practical application, SiO2 is indeed the best support material for this catalyst. However, the comparison in an X-S plot with a reference MnxOy-Na2WO4/SiO2 catalyst indicates that SiC, Fe2O3-based oxides and TiO2-rutile are also promising support materials.

Continuous fixed-bed catalytic hydrogenation of ethylene carbonate (EC) to methanol and ethylene glycol (EG), an emerging synthetic process of methanol via indirect conversion of CO2, was successfully performed over Cu/HMS catalysts prepared by the ammonia evaporation (AE) method. The catalysts possessed superb performance with a conversion of 100% and a selectivity to methanol of 74%.

In-situ attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy and focused-beam reflectance measurement (FBRM) were used to monitor and control the antisolvent crystallization of paracetamol from an acetone–water mixture, which was conducted in a 150 mL flat bottom crystallizer with a Mettler Toledo Easymax Reactor system. Following the monitoring of a series of unseeded and seeded crystallization experiments using a constant addition rate of antisolvent, a simple calculation method for the set point of antisolvent addition rate, to maintain constant supersaturation via ATR-FTIR, was developed and implemented for feedback control of unseeded and seeded crystallizations. The implemented technique used a single peak in the ATR-FTIR spectral region without any calibration to effectively maintain supersaturation to a prespecified set point. By developing a solubility curve in terms of peak height and knowing key information of the process at any given time, the addition rate of antisol...

Amine solutions were applied in carbon dioxide removal from a model mixture of biogas, carried out in a loop reactor system. In addition, the effect of CO2 absorptio acceleration in the presence of ...

A prototype two-stage MSO (molten salt oxidation) reactor system with a capacity of 10 kg/h was developed based on the test results of lab-scale and bench-scale MSO systems. This study first discusses the features of the prototype MSO reactor system. The second part of the study attempts to identify the proper conditions of the prototype two-stage MSO reactor system, where each reactor performs different functions. The volatility of radioactive elements doped in the spent resins was first investigated to establish the proper operating conditions of the primary MSO reactor. A parametric model study of the secondary MSO reactor for the oxidation of hydrocarbons from the primary reactor and an experimental validation were then performed to establish the optimum conditions for the two-stage MSO reactor system. The retention of cesium was greatly influenced by the pyrolysis temperature. The highest pyrolysis temperature with cesium retention of ≥99.9% was 790 °C and this was established as the optimum primary reactor temperature. The optimum conditions of secondary MSO reactor for the substantial oxidation of hydrocarbons generated from the primary MSO reactor were determined to be λ (the ratio of actual air feed rate per stoichiometric air rate) of 2, and a temperature of 800 °C.

Reduction of surface nitrates with C3H6 on a Pt/Al2O3 catalyst was investigated using diffuse reflectance infrared spectroscopy (DRIFTS) and a reactor system designed for monolith-supported catalysts. C3H6 oxidation was inhibited by the presence of NO, and vice versa, and data indicate that adsorbed NOX reacted with gas phase C3H6. DRIFTS results confirm reaction between C3H6 and surface nitrates with linear nitrites as the reaction products. Data show that Pt is required for this reaction, which suggests the nitrates in proximity to the Pt particles are affected/relevant.

Postcombustion CO2 capture systems that use CaO as a regenerable CO2 sorbent in two interconnected circulating fluidized beds (CFBs) are rapidly developing at increasing scale. The properties of the circulating materials, the reactor geometries and operating conditions (gas velocities and temperature ranges) are remarkably similar to those present in existing large scale circulating fluidized bed combustors, CFBCs. In this work a fluid-dynamic model published for CFBCs is adopted and applied to the study of the interconnected twin reactor calcium looping (CaL) system. The model was used to find operating windows that will allow the CaL system to be applied on a large scale. It was found that when operating at high gas velocities (4–5 m/s) in the carbonator, unacceptably high solids circulation rates might be present when high bed inventories are in place to achieve large CO2 capture efficiencies. An additional loop to allow the internal circulation of the excess solids can be quantified with the help of the model used in this work.

Results of full-scale tests have shown that mercury capture in a fabric filter is more effective than in an electrostatic precipitator. This is in accordance with our previous experimental results in which significant amounts of oxidized mercury were easily adsorbed in the filter rather than in the entrained-flow reactor portion. In this study, mercury capture in the filter was modelled using a tanks-in-series model. Based on the experimental results of this study, we conclude that the modelling results predicted an effective mercury capture in the filter.

Das anaerobe gastrointestinale Bakterium Eubacterium ramulus wurde erstmals in einem Einweg-Beutelreaktorsystem mit 10 L Kulturmedium kultiviert. Im Vergleich zu Standard-Flaschenkultivierungen mit Hungate-Technik wurde um den Faktor 25 aufskaliert und die optische Dichte konnte um mehr als das 5fache gesteigert werden. Bei einer 10-L-Batch-Kultivierung im Einweg-Beutelreaktorsystem wurden 60 bis 70 g Feuchtzellmasse produziert. Zum Vergleich wurde eine 10-L-Batch-Kultivierung in einem Edelstahlruhrkessel durchgefuhrt, die ahnliche Ergebnisse wie das Beutelreaktorsystem hinsichtlich der Feuchtzellmasse und der optischen Dichte zeigte. The first anaerobic cultivation of the gastrointestinal bacteria Eubacterium ramulus in a disposable bag reactor system is described. E. ramulus was cultivated in batches up to 10 L culture volume in a novel commercial disposable rocking motion bag reactor system for the first time. Optical densities about 5-fold higher compared to previously used bottle cultivations could be obtained. Produced biomass per batch (10 L bag cultivation) yielded up 60 to 70 g wet cell mass. Comparative batch cultivation with the same volume in a common stirred tank reactor was performed. It showed results similar to the cultivation in the bag reactor system regarding optical density and wet cell mass.

Human mesenchymal stem cells (hMSCs) have significant potential for therapeutic tissue regeneration and repair. The creation of functional 3D constructs from hMSCs depends on the innate ability of MSCs to proliferate and differentiate, and is strongly influenced by the culture conditions. An inherent challenge in investigating 3D cellular construct development is the dynamic monitoring of the cellular and physiological environment over the course of construct formation. In this project, a novel 3D MR-compatible perfusion bioreactor using 3D poly(ethylene terephthalate) scaffolds was developed to provide such monitoring. The bioreactor system integrates cell seeding and growth, supports high density 3D tissue construct growth and facilitates repeated nuclear magnetic resonance (MR) signal acquisitions under both static and perfusion conditions. The reactor system also has the capacity to modulate macroscopic flow modes that simulates various tissue growth environments with repeated MR signal acquisition, providing the ability to gain insight into the dynamic interplay between the stem cells in the developing constructs and their microenvironment. Using 1H MR spectroscopy and MR imaging, localized spectroscopic data as well as imaging-based T2 and diffusion quantification were acquired from the hMSC growth construct for up to 40 days.

Coolant systems in nuclear power plants undergo degradation by various corrosion processes. The carbon steel feeder pipes for the primary heat transport system of pressurised heavy water reactors (PHWRs) undergo extensive wall thinning by a degradation process, known as flow accelerated corrosion (FAC). Flow accelerated corrosion occurs under certain conditions of flow, water chemistry, pipe geometry and material composition. In PHWRs, the outlet feeders carry the heavy water (D2O) coolant, which flows at velocities in the range of 10 to 20 m s−1. The requirement of high flow velocity at high temperature and pressure to simulate the exact service hydrodynamic conditions, and the long time required to enable unambiguous observations regarding the extent of FAC, makes it difficult to undertake this study in the laboratory. This paper presents the design of an FAC module that enables the relatively rapid measurement of FAC to be undertaken in simulated PHWR primary heat transport conditions. The resu...

The very rapid deactivation behavior of Mo/HZSM-5 catalyst in the non-oxidative CH 4 dehydroaromatization needs its cyclic or continuous regeneration operation in a practical reactor system. Design and operation of such a system requires knowledge of the kinetics of catalyst deactivation and its regeneration. The present work reports an easy, rapid and quantitative approach to follow the dynamic variation of the activity of Mo/HZSM-5 in the very initial stage of CH 4 dehydroaromatization at severe conditions. This approach comprises an on-line sampling and storing of a reacted effluent into a number of volume-known loops at intervals from seconds to minutes, and an off-line analysis of the stored samples. With it a nearly continuous dynamic variation in outlet benzene concentration was observed in the first tens of minutes of the reaction for all tested catalysts with Mo loadings ranging from 1.0 to 10 wt.%. Quantitative comparison of the variation with that in the benzene formation rate measured using conventional on-line GC analysis further revealed that the variation actually exhibited the dynamic behavior of the benzene formation activity of catalyst. The approach was subsequently applied successfully to follow the intrinsic maximum activity of Mo/HZSM-5 at severe conditions and in periodic reaction–regeneration operation mode to collect kinetic data for the reactor design.

This paper presents process characteristics and proof of concept reactions for a newly developed microreactor system, termed the Cambridge Disc Microreactor (CDM), using plastic microcapillary flow discs (MFDs). These flat reactor discs were constructed from a flexible, temperature resilient, solvent resistant fluoropolymer microcapillary film (MCF) comprising 10 parallel capillary channels with mean hydraulic diameters typically between 150 and 400 μm. The MFDs were heated inside the microreactor via conductive heat transfer from two heated surfaces, which were in contact with the flat outer surfaces of the disc. This allowed continuous flow processing of liquid phase reactions through the reactor at elevated temperatures and pressures at a precisely controlled residence time. The process characteristics of the reactor system were established experimentally by investigating the hydraulic response and the temperature profile or modeled analytically such that the residence time characteristics inside the d...

The chemical vapor synthesis (CVS) reactor for the preparation of WC nanopowder from tungsten hexachloride was simulated by a two-dimensional multiphase computational fluid dynamics (CFD) model. The model solves the gas-phase governing equations of overall continuity, momentum, energy, and species mass transport inside a tubular reactor system. The population balance model is coupled with the gas-phase equations to describe the formation and growth of WC nanoparticles. The model has been validated with experimental data in terms of average particle size and concentration of unreacted precursor at the outlet. The contours of temperature, velocity, species concentration and particle size distribution (PSD) inside the tubular reactor were computed.

The NO absorption characteristic of calcium hydroxide was investigated in a fixed bed reactor system in the presence of SO2. The effect of O2 and H2O on NO removal was discussed in or without the presence of SO2. When SO2 was excluded from the flue gas, NO removal was slight. The presence of SO2 in the flue gas could enhance NO removal only when both of O2 and H2O were also present. The essence of enhancement of SO2 on NO removal was accelerating the conversion of NO to NO2. The desulfurization reaction product could not oxidize NO to NO2. The bed height experiment revealed that the multimolecular intermediate species, which could decomposed in to NO2, was not formed from the adsorption of NO, H2O, and O2 on the surface of absorbent. The possible reaction path proposed in paper is that there may be some unstable intermediate species formed from the desulfurization reaction, which can enhance the conversion of NO to NO2. The presence of H2O can enhance the presence of unstable intermediate. According to an...

The synthesis of dimethyl carbonate (DMC) from methanol and CO 2 has been investigated using a vapor phase flow reactor system and in the presence of various Rh-supported catalysts. The effects of reaction conditions, supports, and promoters on catalyst performance were evaluated in terms of methanol conversion and DMC selectivity. The results show that DMC synthesis proceeds effectively at low temperatures (353–433 K), while at higher temperatures dimethyl ether (DME) is the predominant product. Loss of surface chloride results in substantial catalyst system deactivation.

The effect of liquid quenching during the hydroprocessing of a heavy crude oil in a fixed-bed reactor system was explored. Experiments were carried out at various operating conditions in a pilot plant equipped with two fixed-bed reactors in series loaded with a triple catalyst system and necessary hardware for injecting quench fluids between reactors. The feed and quench liquid were prepared by splitting a heavy crude oil into two fractions, called light and heavy fractions. The heavy fraction was used as the feed to the reactors, whereas the light fraction was injected between reactors as the quenching liquid. To establish a reference case, a conventional hydrogen quenching scheme was also evaluated by injecting hydrogen instead of the light fraction. It was observed that hydrogen quenching produced only marginally better quality because of a more favorable H2/oil profile. Yet, it was determined that this approach (hydrogen quenching) requires the handling of large volumes of gas, which increases compres...

A three-stage gas−liquid electrical discharge reactor was developed based upon a tray column design. The reactor system was operated in both closed recirculation and multiple pass continuous flow m...

A parallel throughput screening system coupled with GC/MS analysis system was constructed. The system consists of six parallel tubes which can be filled with catalyst materials (particles, nets, monoliths). Different catalyst materials, particle sizes and temperatures were evaluated in catalytic three-phase hydrogenation of citral over Ni/SiO2 catalyst. The reactor system showed good reproducibility.

In this article, the analytic optimization algorithm connected to the measurement-based predictive control framework is implemented on an exothermic tubular reactor system. The two stages of design...