C-Alkylation of N-alkylamides with styrenes in air and scale-up using a microwave flow reactor

Direct air capture (DAC) of CO2 can address CO2 emissions from distributed sources and produce CO2 from air virtually anywhere that it is needed. In this paper, the performance of a new radial flow reactor (RFR) for CO2 adsorption from ambient air is reported. The reactor uses a supported amine sorbent and is operated in a batch mode of operation or semi-continuously, respectively without or with sorbent circulation. The radial flow reactor, containing 2 kg of the adsorbent, is successfully scaled up from the experimental results obtained with a fixed bed reactor using only 1 g of the adsorbent. In the batch operation mode, the sorbent in the annular space of the RFR is regenerated in situ. With sorbent circulation, the RFR is loaded and unloaded batchwise and only used as an adsorber. A sorbent batch loaded with CO2 is transported to and regenerated in an external (fluid bed) regenerator. The RFR unit is characterized by a low contacting energy (0.7–1.5 GJ/ton-CO2) and a relatively short adsorption time (24–43 min) compared to other DAC processes using the same types of sorbents. The contactor concept is ready for further scale-up and continuous application.

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Effect of Aspect Ratio on the Mixing Performance in the Kenics Static Mixer

Processes ◽

10.3390/pr9030464 ◽

2021 ◽

Vol 9 (3) ◽

pp. 464

Author(s):

Xingren Jiang ◽

Ning Yang ◽

Rijie Wang

Keyword(s):

Pharmaceutical Industry ◽

Aspect Ratio ◽

Flow Reactor ◽

Mixing Time ◽

Continuous Process ◽

Scale Up ◽

Influence Factors ◽

Continuous Manufacturing ◽

Static Mixer ◽

Mixing Performance

Continuous manufacturing has received increasing interest because of the advantages of intrinsic safety and enhanced mass transfer in the pharmaceutical industry. However, the difficulty for scale-up has limited the application of continuous manufacturing for a long time. Recently, the tubular flow reactor equipped with the Kenics static mixer appears to be a solution for the continuous process scale-up. Although many influence factors on the mixing performance in the Kenics static mixer have been investigated, little research has been carried out on the aspect ratio. In this study, we used the coefficient of variation as the mixing evaluation index to investigate the effect of the aspect ratio (0.2–2) on the Kenics static mixer’s mixing performance. The results indicate that a low aspect ratio helps obtain a shorter mixing time and mixer length. This study suggests that adjusting the aspect ratio of the Kenics static mixer can be a new strategy for the scale-up of a continuous process in the pharmaceutical industry.

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Scale-up of a photochemical flow reactor for the production of lignin-coated titanium dioxide as a sunscreen ingredient

Journal of Photochemistry and Photobiology ◽

10.1016/j.jpap.2021.100040 ◽

2021 ◽

pp. 100040

Author(s):

Kelsey Fournier ◽

Nancy Marina ◽

Neeraj Joshi ◽

Vincent R. Berthiaume ◽

Sara Currie ◽

...

Keyword(s):

Titanium Dioxide ◽

Flow Reactor ◽

Scale Up

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Diels–Alder reactions of myrcene using intensified continuous-flow reactors

Beilstein Journal of Organic Chemistry ◽

10.3762/bjoc.13.15 ◽

2017 ◽

Vol 13 ◽

pp. 120-126 ◽

Cited By ~ 8

Author(s):

Christian H Hornung ◽

Miguel Á Álvarez-Diéguez ◽

Thomas M Kohl ◽

John Tsanaktsidis

Keyword(s):

Continuous Flow ◽

Flow Reactor ◽

Scale Up ◽

Reaction Times ◽

Alder Reaction ◽

Diels Alder ◽

Flow Reactors ◽

Diels Alder Reaction ◽

Naturally Occurring ◽

Continuous Flow Reactors

This work describes the Diels–Alder reaction of the naturally occurring substituted butadiene, myrcene, with a range of different naturally occurring and synthetic dienophiles. The synthesis of the Diels–Alder adduct from myrcene and acrylic acid, containing surfactant properties, was scaled-up in a plate-type continuous-flow reactor with a volume of 105 mL to a throughput of 2.79 kg of the final product per day. This continuous-flow approach provides a facile alternative scale-up route to conventional batch processing, and it helps to intensify the synthesis protocol by applying higher reaction temperatures and shorter reaction times.

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In situ secondary organic aerosol formation from ambient pine forest air using an oxidation flow reactor

Atmospheric Chemistry and Physics Discussions ◽

10.5194/acpd-15-30409-2015 ◽

2015 ◽

Vol 15 (21) ◽

pp. 30409-30471 ◽

Cited By ~ 4

Author(s):

B. B. Palm ◽

P. Campuzano-Jost ◽

A. M. Ortega ◽

D. A. Day ◽

L. Kaser ◽

...

Keyword(s):

Organic Compounds ◽

Flow Reactor ◽

Secondary Organic Aerosol ◽

Ambient Air ◽

Organic Aerosol ◽

Pine Forest ◽

Oxidation Products ◽

Oh Radicals ◽

Aerosol Formation ◽

Photochemical Aging

Abstract. Ambient air was oxidized by OH radicals in an oxidation flow reactor (OFR) located in a montane pine forest during the BEACHON-RoMBAS campaign to study biogenic secondary organic aerosol (SOA) formation and aging. High OH concentrations and short residence times allowed for semi-continuous cycling through a large range of OH exposures ranging from hours to weeks of equivalent (eq.) atmospheric aging. A simple model is derived and used to account for the relative time scales of condensation of low volatility organic compounds (LVOCs) onto particles, condensational loss to the walls, and further reaction to produce volatile, non-condensing fragmentation products. More SOA production was observed in the OFR at nighttime (average 4 μg m-3 when LVOC fate corrected) compared to daytime (average 1 μg m-3 when LVOC fate corrected), with maximum formation observed at 0.4–1.5 eq. days of photochemical aging. SOA formation followed a similar diurnal pattern to monoterpenes, sesquiterpenes, and toluene + p-cymene concentrations, including a substantial increase just after sunrise at 07:00 LT. Higher photochemical aging (> 10 eq. days) led to a decrease in new SOA formation and a loss of preexisting OA due to heterogeneous oxidation followed by fragmentation and volatilization. When comparing two different commonly used methods of OH production in OFRs (OFR185 and OFR254), similar amounts of SOA formation were observed. We recommend the OFR185 mode for future forest studies. Concurrent gas-phase measurements of air after OH oxidation illustrate the decay of primary VOCs, production of small oxidized organic compounds, and net production at lower ages followed by net consumption of terpenoid oxidation products as photochemical age increased. New particle formation was observed in the reactor after oxidation, especially during times when precursor gas concentrations and SOA formation were largest. Approximately 6 times more SOA was formed in the reactor from OH oxidation than could be explained by the VOCs measured in ambient air. Several recently-developed instruments quantified ambient semi- and intermediate-volatility organic compounds (S/IVOCs) that were not detected by a PTR-TOF-MS. An SOA yield of 24–80 % from those compounds can explain the observed SOA, suggesting that these typically unmeasured S/IVOCs play a substantial role in ambient SOA formation. Our results allow ruling out condensation sticking coefficients much lower than 1. Our measurements help clarify the magnitude of SOA formation in forested environments, and demonstrate methods for interpretation of ambient OFR measurements.

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Volatility and lifetime against OH heterogeneous reaction of ambient Isoprene Epoxydiols-Derived Secondary Organic Aerosol (IEPOX-SOA)

10.5194/acp-2016-418 ◽

2016 ◽

Cited By ~ 2

Author(s):

Weiwei Hu ◽

Brett B. Palm ◽

Douglas A. Day ◽

Pedro Campuzano-Jost ◽

Jordan E. Krechmer ◽

...

Keyword(s):

Flow Reactor ◽

Secondary Organic Aerosol ◽

Heterogeneous Reaction ◽

Ambient Air ◽

Organic Aerosol ◽

Amazon Forest ◽

Reaction Products ◽

Ambient Conditions ◽

Forested Areas ◽

Humidity Dependence

Abstract. Isoprene epoxydiols-derived secondary organic aerosol (IEPOX-SOA) can contribute substantially to organic aerosol (OA) concentrations in forested areas under low NO conditions, hence significantly influencing the regional and global OA budgets, accounting for example for 16–36 % of the submicron OA in the SE US summer. Particle evaporation measurements from a thermodenuder show that the volatility of ambient IEPOX-SOA is lower than that of bulk OA and also much lower than that of known monomer IEPOX-SOA tracer species, indicating that IEPOX-SOA likely exists mostly as oligomers in the aerosol phase. The OH aging process of ambient IEPOX-SOA was investigated with an oxidation flow reactor (OFR). New IEPOX-SOA formation in the reactor was negligible, as the OFR cannot accelerate processes such as aerosol uptake and reactions that do not scale with OH. Simulation results indicate that adding ~ 100 µg m−3 of pure H2SO4 to the ambient air allows to efficiently form IEPOX-SOA in the reactor. The heterogeneous reaction rate coefficient of ambient IEPOX-SOA with OH radical (kOH) was estimated as 4.0 ± 2.0 × 10−13 cm3 molec−1 s−1, which is equivalent to more than a 2-week lifetime. A similar kOH was found for measurements of OH oxidation of ambient Amazon forest air in an OFR. At higher OH exposures in the reactor (> 1 × 1012 molec. cm−3 s), the mass loss of IEPOX-SOA due to heterogeneous reaction was mainly due to revolatilization of fragmented reaction products. We report for the first time OH reactive uptake coefficients (γOH = 0.59 ± 0.33 in SE US and γOH = 0.68 ± 0.38 in Amazon) for SOA under ambient conditions. A relative humidity dependence of kOH and γOH was observed, consistent with surface area-limited OH uptake. No decrease of kOH was observed as OH concentrations increased. These observation of physicochemical properties of IEPOX-SOA can help to constrain OA impact on air quality and climate.

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Reactor scale-up in AOPs: from laboratory to commercial scale

Water Science & Technology ◽

10.2166/wst.2004.0207 ◽

2004 ◽

Vol 49 (4) ◽

pp. 13-18 ◽

Cited By ~ 7

Author(s):

C.S. Zalazar ◽

M.D. Labas ◽

C.A. Martín ◽

R.J. Brandi ◽

A.E. Cassano

Keyword(s):

Formic Acid ◽

Large Scale ◽

Flow Reactor ◽

Acid Output ◽

Water Solution ◽

Batch Reactor ◽

Scale Up ◽

Mass Balances ◽

Tubular Flow Reactor ◽

Tubular Flow

A procedure to scale-up photoreactors employed in AOPs using laboratory information has been developed. Operating with a model compound the proposed procedure was applied to the decomposition of formic acid in water solution using hydrogen peroxide and UV radiation. With laboratory experiments the parameters of the kinetic equation were obtained in a small batch reactor operated within a recycling apparatus. The whole system was modeled employing radiation and mass balances. These balances were used together with a non-linear parameter estimator to derive the model kinetic constants. Then, these results were used in the modeling of the large-scale reactor to predict exit conversions in an isothermal, continuous, tubular flow reactor that is 2 m long and has a volume of 12 l. Once more, radiation and mass balances were used to predict formic acid output concentrations. Experimental data in the large-scale apparatus are in good agreement with theoretical predictions.

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