Photocatalytic abatement of o-xylene using adsorption enhanced ZnO/GAC catalyst in a continuous flow reactor: Catalytic potential, Fate of o-xylene and its by-products

Photocatalytic abatement of o-xylene was investigated by immobilized ZnO on granular activated carbon (ZnO/GAC) under UV irradiation. Immobilization of ZnO increased the breakthrough time and removal capacity by 51 and 57%, respectively, in optimal conditions. The catalytic potential of the ZnO/GAC (86.5%) for o-xylene removal was far greater than simple GAC (13.5%), at the optimum condition. The maximum removal capacity with ZnO/GAC (3.12g o-xylene /gZnO/GAC) was observed at 100 °C, while the maximum removal capacity of simple GAC (1.37 g o-xylene/g GAC) was observed a t 20 °C. The main intermediates of the o-xylene oxidation in photocatalytic process with GAC were methanoic acid, o-nitro-p-cresol, phenylmethanal, and methyl di-phenyl-methane. ZnO/GAC can highly catalyze the degradation of o-xylene in the presence of UV, with methanoic acid being the major intermediate desorbed from the bed. The results demonstrated that the ZnO/GAC is an efficient option for the removal of VOCs and biohazards emitted from industrial streams.

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Rapid Determination of Optimal Conditions in a Continuous Flow Reactor Using Process Analytical Technology

Processes ◽

10.3390/pr2010024 ◽

2013 ◽

Vol 2 (1) ◽

pp. 24-33 ◽

Cited By ~ 3

Author(s):

Michael Roberto ◽

Thomas Dearing ◽

Charles Branham ◽

Olav Bleie ◽

Brian Marquardt

Keyword(s):

Continuous Flow ◽

Flow Reactor ◽

Process Analytical Technology ◽

Rapid Determination ◽

Optimal Conditions ◽

Continuous Flow Reactor ◽

Analytical Technology

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Continuous Diastereomeric Kinetic Resolution—Silybins A and B

Catalysts ◽

10.3390/catal11091106 ◽

2021 ◽

Vol 11 (9) ◽

pp. 1106

Author(s):

David Biedermann ◽

Martina Hurtová ◽

Oldřich Benada ◽

Kateřina Valentová ◽

Lada Biedermannová ◽

...

Keyword(s):

Flow Rate ◽

Kinetic Resolution ◽

Flow Reactor ◽

Scale Up ◽

Acrylic Resin ◽

Optimal Conditions ◽

Continuous Flow Reactor ◽

Resin Beads ◽

Diastereomeric Mixture ◽

Optically Pure

The natural diastereomeric mixture of silybins A and B is often used (and considered) as a single flavonolignan isolated from the fruit extract of milk thistle (Silybum marianum), silymarin. However, optically pure silybin diastereomers are required for the evaluation of their biological activity. The separation of silybin diastereomers by standard chromatographic methods is not trivial. Preparative chemoenzymatic resolution of silybin diastereomers has been published, but its optimization and scale-up are needed. Here we present a continuous flow reactor for the chemoenzymatic kinetic resolution of silybin diastereomers catalyzed by Candida antarctica lipase B (CALB) immobilized on acrylic resin beads (Novozym® 435). Temperature, flow rate, and starting material concentration were varied to determine optimal reaction conditions. The variables observed were conversion and diastereomeric ratio. Optimal conditions were chosen to allow kilogram-scale reactions and were determined to be −5 °C, 8 g/L silybin, and a flow rate of 16 mL/min. No significant carrier degradation was observed after approximately 30 cycles (30 days). Under optimal conditions and using a 1000 × 15 mm column, 20 g of silybin per day can be easily processed, yielding 6.7 and 5.6 g of silybin A and silybin B, respectively. Further scale-up depends only on the size of the reactor.

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Renewable Energy from Agricultural Waste

Revista de Chimie ◽

10.37358/rc.18.6.6325 ◽

2018 ◽

Vol 69 (6) ◽

pp. 1363-1366 ◽

Cited By ~ 1

Author(s):

Stefania Daniela Bran ◽

Petre Chipurici ◽

Mariana Bran ◽

Alexandru Vlaicu

Keyword(s):

Saccharomyces Cerevisiae ◽

Gas Chromatography ◽

Continuous Flow ◽

Laboratory Experiments ◽

Fermentation Process ◽

Flow Reactor ◽

Agricultural Waste ◽

Continuous Flow Reactor ◽

Natural Support ◽

Co2 Flow

This paper has aimed at evaluating the concentration of bioethanol obtained using sunflower stem as natural support, molasses as carbon source and Saccharomyces cerevisiae yeast in a continuous flow reactor. The natural support was tested to investigate the immobilization/growth of S. cerevisiae yeast. The concentration of bioethanol produced by fermentation was analyzed by gas chromatography using two methods: aqueous solutions and extraction in organic phase. The CO2 flow obtained during the fermentation process was considered to estimate when the yeast was deactivated. The laboratory experiments have highlighted that the use of plant-based wastes to bioconversion in ethanol could be a non-pollutant and sustainable alternative.

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Thermocatalytic Hydrodeoxygenation and Depolymerization of Waste Lignin to Oxygenates and Biofuels in a Continuous Flow Reactor at Atmospheric Pressure

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.0c02102 ◽

2020 ◽

Vol 8 (35) ◽

pp. 13195-13205 ◽

Cited By ~ 2

Author(s):

Swathi Mukundan ◽

Daria Boffito ◽

Abhijit Shrotri ◽

Luqman Atanda ◽

Jorge Beltramini ◽

...

Keyword(s):

Atmospheric Pressure ◽

Continuous Flow ◽

Flow Reactor ◽

Continuous Flow Reactor

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Optimization of banana crop by-products solvent extraction for the production of bioactive compounds

Biomass Conversion and Biorefinery ◽

10.1007/s13399-021-01703-7 ◽

2021 ◽

Author(s):

Sara Díaz ◽

Antonio N. Benítez ◽

Sara Ramírez-Bolaños ◽

Lidia Robaina ◽

Zaida Ortega

Keyword(s):

Antioxidant Activity ◽

Aqueous Ethanol ◽

Ethanol Concentration ◽

Extraction Process ◽

Total Phenol Content ◽

Optimal Conditions ◽

Satisfactory Description ◽

Optimized Conditions ◽

By Products ◽

Banana Crops

AbstractThe aim of this work is the optimization of phenolic compound extraction from three by-products of banana crops (rachis, discarded banana, and banana’s pseudostem pulp), as a way to valorize them through a green extraction process. The influence of the temperature and aqueous ethanol concentration (Et-OH) on extract properties (total phenol content (TPC) and antioxidant activity) was firstly analyzed. 78 ℃ and ethanol concentrations close to 50% yielded the best results for the three materials. The equations obtained by the response surface methodology gave a satisfactory description of the experimental data, allowing optimizing the extraction conditions. Under optimized conditions, time influence was then assessed, although this parameter seemed not influence results. Among the three by-products, rachis extract (60% Et-OH, 78 ℃, and 30 min) presented the highest TPC (796 mg gallic acid/100 g of dried material) and antioxidant activity (6.51 mg Trolox equivalents/g of dried material), followed by discarded banana, and pseudostem pulp. Under the optimal conditions, experiments were performed at a larger scale, allowing to determine the extraction yields (EY) and to characterize the extracts. The highest EY was obtained for the rachis (26%), but the extract with the highest activity was obtained for discarded banana (50% Et-OH, 78 ℃, and 60 min), which presented a TPC of 27.26 mg/g extract corresponding to 54.59 mg Trolox equivalents/g extract. This study contributes to the valorization of banana crops residues as a source of polyphenolic compounds with bioactive functions that can be extracted under economic extraction conditions. Graphical abstract

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Synthesis of Polyaniline Coating on the Modified Fiber Ball and Application for Cr(VI) Removal

Nanoscale Research Letters ◽

10.1186/s11671-021-03509-y ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Xiao Li Ma ◽

Guang Tao Fei ◽

Shao Hui Xu

Keyword(s):

Waste Water ◽

Large Scale ◽

Ph Value ◽

Low Cost ◽

Strong Acid ◽

Removal Capacity ◽

Secondary Pollution ◽

Potential Possibility ◽

Fiber Ball ◽

Maximum Removal

Abstract In this study, polyaniline (PANI) is prepared by means of chemical oxidization polymerization and directly loaded on the modified fiber ball (m-FB) to obtain macroscale polyaniline/modified fiber ball (PANI/m-FB) composite, and then its removal ability of Cr(VI) is investigated. The effects of different parameters such as contact time, pH value and initial concentration on Cr(VI) removal efficiency are discussed. The experimental results illustrate that the favorable pH value is 5.0 and the maximum removal capacity is measured to be 293.13 mg g−1. Besides, PANI/m-FB composites can be regenerated and reused after being treated with strong acid. The kinetic study indicates that the adsorption procedure is mainly controlled by chemical adsorption. More importantly, the macroscale of composites can avoid secondary pollution efficiently. Benefiting from the low cost, easy preparation in large scale, environmentally friendly, excellent recycling performance as well as high removal ability, PANI/m-FB composites exhibit a potential possibility to remove Cr(VI) from industrial waste water. Graphic Abstract The polyaniline (PANI) was coated on modified fiber ball (m-FB) to remove Cr(VI) in waste water, and this kind of PANI/m-FB composites can avoid secondary pollution efficiently due to its macrostructure. Furthermore, the removal capacity can reach to 291.13 mg/g and can be multiple reused.

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Preparation, Characterization, and Activity of Pd/PSS-Modified Membranes in the Low Temperature Dry Reforming of Methane with and without Addition of Extra Steam

Membranes ◽

10.3390/membranes11070518 ◽

2021 ◽

Vol 11 (7) ◽

pp. 518

Author(s):

Cecilia Mateos-Pedrero ◽

Miguel A. Soria ◽

Antonio Guerrero-Ruíz ◽

Inmaculada Rodríguez-Ramos

Keyword(s):

Low Temperature ◽

Flow Reactor ◽

Dry Reforming ◽

Dry Reforming Of Methane ◽

Porous Stainless Steel ◽

Pd Membrane ◽

Continuous Flow Reactor ◽

Oxidation In Air ◽

H2 Yield ◽

Water Gas

The external surface of a commercial porous stainless steel (PSS) was modified by either oxidation in air at varying temperatures (600, 700, and 800 °C) or coating with different oxides (SiO2, Al2O3, and ZrO2). Among them, PSS-ZrO2 appears as the most suitable carrier for the synthesis of the Pd membrane. A composite Pd membrane supported on the PSS-ZrO2 substrate was prepared by the electroless plating deposition method. Supported Ru catalysts were first evaluated for the low-temperature methane dry reforming (DRM) reaction in a continuous flow reactor (CR). Ru/ZrO2-La2O3 catalyst was found to be active and stable, so it was used in a membrane reactor (MR), which enhances the methane conversions above the equilibrium values. The influence of adding H2O to the feed of DRM was investigated over a Ru/ZrO2-La2O3 catalyst in the MR. Activity results are compared with those measured in a CR. The addition of H2O into the feed favors other reactions such as Water-Gas Shift (RWGS) and Steam Reforming (SR), which occur together with DRM, resulting in a dramatic decrease of CO2 conversion and CO production, but a marked increase of H2 yield.

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