scholarly journals Microwave-Assisted Continuous Flow for the Selective Oligomerization of Glycerol

Catalysts ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 166
Author(s):  
Remi Nguyen ◽  
Nicolas Galy ◽  
Fatmah Alasmary ◽  
Christophe Len
Keyword(s):  
Residence Time ◽  
Flow Rate ◽  
Continuous Flow ◽  
Short Distance ◽  
Microwave Activation ◽  
Commercial Catalyst ◽  
Microwave Assisted ◽  
Effects Of Temperature ◽  
Branched Chain ◽  
First Time

The continuous oligomerization of glycerol for the formation of polyglycerol was carried out for the first time under microwave activation. In the presence of potassium carbonate, we studied the ease of handling, effects of temperature, flow rate and residence time of an inexpensive homogeneous commercial catalyst. The main linear and branched-chain diglycerol and triglycerol regioisomers were characterized and the quantification of the different isomers was realized. Successive cyclic mode processes followed by short distance distillation allowed the mixture to be enriched with glycerol ethers and thus to obtain a mixture of diglycerol (50.2 wt%), triglycerol (22.1 wt%), tetraglycerol (9.5 wt%), and pentaglycerol (4.3 wt%).

Microwave-Assisted Grafting to MCM-41 Silica and its Application as Catalyst in Flow Chemistry

2011 ◽  
Vol 64 (11) ◽  
pp. 1522 ◽  
Author(s):  
Manuela Oliverio ◽  
Antonio Procopio ◽  
Toma N. Glasnov ◽  
Walter Goessler ◽  
C. Oliver Kappe
Keyword(s):  
Continuous Flow ◽  
Rate Increase ◽  
Flow Chemistry ◽  
Conventional Heating ◽  
Kinetic Effect ◽  
Microwave Technology ◽  
Microwave Assisted ◽  
Technology Control ◽  
First Time ◽  
Mcm 41

Finding environmentally gentle methods to graft Lewis acid on the surface of mesoporous materials is a topic of current interest. Herein we describe the optimization of a preparation procedure of a mesoporous silica-supported ErIII catalyst using the microwave-assisted post-calcination functionalization of Mobil Composition of Matter-41 silica as the key step. The required time for functionalization was reduced from several hours to 10 min using sealed-vessel microwave technology. Control experiments using conventional heating at the same temperature demonstrated that the rate increase is owing to a simple thermal/kinetic effect as a result of the higher reaction temperature. The resulting ErIII catalyst was tested for the first time as a catalyst in the continuous flow deprotection of benzaldehyde dimethylacetal and a complete leaching study was performed.

scholarly journals Pengaruh Waktu Tinggal dan Media Tanam pada Constructed Wetland untuk Mengolah Air Limbah Industri Tahu

2020 ◽  
Vol 5 (2) ◽  
pp. 107-115
Author(s):  
Muhammad Al Kholif ◽  
Pungut ◽  
Sugito ◽  
Joko Sutrisno ◽  
Winda Sulistyo Dewi
Keyword(s):  
Constructed Wetlands ◽  
Residence Time ◽  
Flow Rate ◽  
Constructed Wetland ◽  
Continuous Flow ◽  
Industrial Waste ◽  
Efficient Treatment ◽  
High Burden ◽  
Industry Waste ◽  
The Media

Tofu industry waste pollution is still a serious problem. The high burden of tofu industrial waste pollutants is still a major problem. besides, the unavailability of the budget for processing and the limitations of a cheap and efficient treatment system are factors supporting the pollution of tofu waste in the environment. This study examines the efficiency of reducing BOD5 and COD treated with constructed wetlands using water jasmine plants (Enchinodorus palaefolius). The system used is the wetland subsurface with continuous flow. The media used include sand and biochar with a residence time of 12 hours 18 hours. Whereas pH, temperature, and flow rate are conditioned as control variables. The greatest efficiency of BOD5 and COD occurs in reactors using biochar media and a residence time of 18 hours with an efficiency of BOD5 of 50.52% and COD of 55.02%.

scholarly journals CONTINUOUS INDUSTRIAL-SCALE MICROWAVE-ASSISTED EXTRACTION OF HIGH-VALUE INGREDIENTS FROM NATURAL BIOMASS

2019 ◽  
Author(s):  
Steven Splinter ◽  
Marilena Radoiu
Keyword(s):  
Energy Transfer ◽  
Residence Time ◽  
Microwave Power ◽  
Continuous Flow ◽  
Microwave Energy ◽  
Industrial Scale ◽  
Innovative Technology ◽  
Microwave Assisted ◽  
Assisted Extraction ◽  
Wide Range

An innovative technology for the continuous extraction of bioactive compounds from a wide range of biological materials has been developed, scaled up and successfully demonstrated at commercially-relevant scales. The technology, known as MAPTM, or “Microwave-Assisted Process”, robustly transfers from laboratory to continuous, industrial scale operation.  In wide-ranging trials, MAPTM has comprehensively demonstrated its ability to outperform many KPIs of conventional extraction processes, while offering biomass throughput, product consistency and low operational costs not attainable by other emerging technologies. Radient’s proprietary continuous-flow MAPTM extractor, Figure 1, was designed for continuous processing of up to 200 kg/h of biomass material. Verification of the mechanical integrity of the system was confirmed by flow testing of biomass / solvent slurries. Testing and verification of the efficiency of microwave energy transfer to the extractor cavity was completed at various microwave power settings using flowing water at 870 kg/h.  The microwave energy transfer to the system was verified to be >95 % in each case. As an example of performance, continuous flow MAPTM extraction of the antioxidant SDG from flax biomass was performed using 70 % ethanol / water as the solvent at two different conditions: -          75 kg/h flax / 5 L/kg solvent / 15 kW microwave power / extractor residence time 24 min; -          110 kg/h flax / 5 L/kg solvent / 20 kW microwave power / extractor residence time 16 min. The industrial-scale conditions for these runs were determined by extrapolating from optimized conditions previously obtained from batch lab-scale MAPTM experiments. The continuous flow approach eliminates the requirement for having geometric similarity between scales, i.e the equipment shape and dimensions do not have to scale proportionately.

New Insights into the Nature of the Band Gap of CuGeO3 Nanoparticles: Synthesis, Electronic Structure, and Optical and Photocatalytic Properties

2019 ◽  
Author(s):  
Victor Y. Suzuki ◽  
Luís Henrique Cardozo Amorin ◽  
Natália H. de Paula ◽  
Anderson R. Albuquerque ◽  
Julio Ricardo Sambrano ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Band Gap ◽  
Material Design ◽  
Photocatalytic Properties ◽  
Critical Parameters ◽  
Synthetic Approach ◽  
Microwave Assisted ◽  
Theoretical Approaches ◽  
Nanoparticles Synthesis ◽  
First Time

<p>We report, for the first time, new insights into the nature of the band gap of <a>CuGeO<sub>3</sub> </a>(CGO) nanocrystals synthesized from a microwave-assisted hydrothermal method in the presence of citrate. To the best of our knowledge, this synthetic approach has the shortest reaction time and it works at the lowest temperatures reported in the literature for the preparation of these materials. The influence of the surfactant on the structural, electronic, optical, and photocatalytic properties of CGO nanocrystals is discussed by a combination of experimental and theoretical approaches, and that results elucidates the nature of the band gap of synthetized CGO nanocrystals. We believe that this particular strategy is one of the most critical parameters for the development of innovative applications and that result could shed some light on the emerging material design with entirely new properties.</p> <p><b> </b></p>

Removal of trichloroethylene and trichloroethane using a novel hollow-fibre gas-permeable membrane

2003 ◽  
Vol 3 (5-6) ◽  
pp. 67-72
Author(s):  
S. Takizawa ◽  
T. Win
Keyword(s):  
Boundary Layer ◽  
Flow Regime ◽  
Removal Efficiency ◽  
Residence Time ◽  
Flow Rate ◽  
Air Flow ◽  
Hollow Fibre ◽  
Permeation Rate ◽  
Permeable Membrane ◽  
Diffusional Boundary Layer

In order to evaluate effects of operational parameters on the removal efficiency of trichloroethylene and 1,1,1-trichloroethene from water, lab-scale experiments were conducted using a novel hollow-fibre gaspermeable membrane system, which has a very thin gas-permeable membrane held between microporous support membranes. The permeation rate of chlorinated hydrocarbons increased at higher temperature and water flow rate. On the other hand, the effects of the operational conditions in the permeate side were complex. When the permeate side was kept at low pressure without sweeping air (pervaporation), the removal efficiency of chlorinated hydrocarbon, as well as water permeation rate, was low probably due to lower level of membrane swelling on the permeate side. But when a very small amount of air was swept on the membrane (air perstripping) under a low pressure, it showed a higher efficiency than in any other conditions. Three factors affecting the permeation rate are: 1) reduction of diffusional boundary layer within the microporous support membrane, 2) air/vapour flow regime and short cutting, and 3) the extent of membrane swelling on the permeate side. A higher air flow, in general, reduces the diffusional boundary layer, but at the same time disrupts the flow regime, causes short cutting, and makes the membrane dryer. Due to these multiple effects on gas permeation, there is an optimum operational condition concerning the vacuum pressure and the air flow rate. Under the optimum operational condition, the residence time within the hollow-fibre membrane to achieve 99% removal of TCE was 5.25 minutes. The log (removal rate) was linearly correlated with the average hydraulic residence time within the membrane, and 1 mg/L of TCE can be reduced to 1 μg/L (99.9% removal).

The role of pathos: from argumentative responses to feeling and emotions

2017 ◽  
Author(s):  
Michel Meyer
Keyword(s):  
Short Distance ◽  
Social World ◽  
Legal Rhetoric ◽  
Law And Politics ◽  
The Social ◽  
And Behavior ◽  
First Time

Chapter 10 is devoted to the role of emotions or pathos. Pathos was the term ordinarily used to denote the notion of audience. For the first time since Aristotle, emotions receive a full role in a treatise on rhetoric. The responses of the audience are modulated by its emotions. What is their nature and how precisely do they operate? The areas of political and legal rhetoric are examined here in the light of an original view of the theory of distance: values at greater distance become passions at short distance, and this is one of the features which demarcates politics from law. Law and politics are not merely argumentative, nor are they entirely emotional. The norms they codify are often implicit in their shaping of our mutual expectations and behavior in the social world.

Defluoridation of drinking water by magnesium and aluminum electrocoagulation in continuous flow-rate: A response surface design.

2021 ◽  
pp. 1-37
Author(s):  
Ana Gabriela Sierra-Sánchez ◽  
Verónica Martínez-Miranda ◽  
Elia Alejandra Teutli-Sequeira ◽  
Ivonne Linares-Hernández ◽  
Guadalupe Vázquez-Mejía ◽  
...  
Keyword(s):  
Drinking Water ◽  
Response Surface ◽  
Flow Rate ◽  
Continuous Flow ◽  
Response Surface Design ◽  
Surface Design

THE FLAGELLATION, MOVEMENT, AND ENCYSTMENT OF SOME PHYCOMYCETOUS ZOOSPORES

1962 ◽  
Vol 8 (6) ◽  
pp. 897-904 ◽  
Author(s):  
W. E. McKeen
Keyword(s):  
Short Distance ◽  
Pythium Aphanidermatum ◽  
Concave Side ◽  
Central Axis ◽  
Saprolegnia Parasitica ◽  
Anterior Flagellum ◽  
Posterior Flagellum ◽  
Phytophthora Fragariae ◽  
First Time ◽  
The Way

The anterior flagellum of the zoospores of Phytophthora fragariae, P. megasperma, P. cambivora, Saprolegnia parasitica, Achlya americana, and Pythium aphanidermatum projects straight in front of the zoospore and never moves except during encystment whereas the posterior flagellum is active during the swimming period. In the secondary zoospore the anterior and posterior flagella are attached a short distance apart in the center of the depression on the concave side and respectively pass forward and backward through a groove and form a central axis about which the zoospore rotates. Hyaline vesicles which also have been called beads or paddles form at the base of the flagella at the beginning of encystment and glide part or all the way down the flagella. Movement of flagella after they are released from the zoospore is reported for the first time. Encystment may result from contact stimulus except in the case of Allomyces anomalus. A filament on which vesicles may occur may be secreted or retracted by the Allomyces zoospore.

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