Green Process for Selective Ester Production Using Heterogeneous Resin Catalyst with Different Reaction Field

2021 ◽  
Author(s):  
Kousuke Hiromori ◽  
Naomi Shibasaki-Ktakawa ◽  
Atushi Takahashi ◽  
Kazuki Murakami
Keyword(s):  
Green Process ◽  
Reaction Field ◽  
Resin Catalyst

Using Low Temperature, Cost-effective and Green Methods to Carbon Nanohorn Synthesis

2019 ◽  
Vol 9 (2) ◽  
pp. 157-160
Author(s):  
Ali Hasani
Keyword(s):  
Laser Ablation ◽  
Melting Point ◽  
Palm Olein ◽  
Arc Discharge ◽  
Low Cost ◽  
The Other ◽  
High Yield ◽  
Reaction Field ◽  
Carbon Nanohorns ◽  
Graphite Rod

Background: Laser ablation method has high-yield and pure SWCNHs. On the other hand, arc discharge methods have low-cost production of SWCNHs. However, these techniques have more desirable features, they need special expertness to use high power laser or high current discharge that either of them produces very high temperature. As for the researches, the temperatures of these techniques are higher than 4727°C to vaporize the graphite. So, to become aware of the advantages of SWCNHs, it is necessary to find a new way to synthesize SWCNHs at a lower temperature. In other words, reaction field can be expandable at a moderate temperature. This paper reports a new way to synthesize SWCNHs at an extremely reduced temperature. Methods: According to this study, the role of N2 is the protection of the copper holder supporting the graphite rod by increasing heat transfer from the holder. After the current of 70 A was supplied to the system, the temperature of graphite rod was raised to 1600°C. It is obvious that this temperature is somehow higher than the melting point of palladium, 1555°C, and much lower than graphite melting point, 3497°C. Results: Based on the results, there are transitional precursors simultaneous with the SWCNHs. This composition can be created by distortion of the primary SWCNTs at the higher temperature. Subsequently, each SWCNTs have a tendency to be broken into individual horns. With increasing the concentration of the free horns, bud-like SWCNHs can be produced. Moreover, there are individual horns almost separated from the mass of single wall carbon nanohorns. This structure is not common in SWCNHs synthesized by the usual method such as arc discharge or laser ablation. Through these regular techniques, SWCNHs are synthesized as cumulative particles with diameters about 30-150 nm. Conclusion: A simple heating is needed for SWCNTs transformation to SWCNHs with the presence of palladium as catalyst. The well-thought-out mechanism for this transformation is that SWCNTs were initially changed to highly curled shape, and after that were formed into small independent horns. The other rout to synthesize SWCNHs is the pyrolysis of palm olein at 950°C with the assistance of zinc nitrate and ferrocene. Palm olein was used as a promising, bio-renewable and inexpensive carbon source for the production of carbon nanohorns.

scholarly journals Elastostatics of Bernoulli–Euler Beams Resting on Displacement-Driven Nonlocal Foundation

Nanomaterials ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 573
Author(s):  
Marzia Sara Vaccaro ◽  
Francesco Paolo Pinnola ◽  
Francesco Marotti de Sciarra ◽  
Raffaele Barretta
Keyword(s):  
Boundary Conditions ◽  
Structural Engineering ◽  
Beam Deflection ◽  
Soil Reaction ◽  
Differential Problem ◽  
Reaction Field ◽  
Ill Posed ◽  
Elastic Responses ◽  
Benchmark Solutions ◽  
Well Posed

The simplest elasticity model of the foundation underlying a slender beam under flexure was conceived by Winkler, requiring local proportionality between soil reactions and beam deflection. Such an approach leads to well-posed elastostatic and elastodynamic problems, but as highlighted by Wieghardt, it provides elastic responses that are not technically significant for a wide variety of engineering applications. Thus, Winkler’s model was replaced by Wieghardt himself by assuming that the beam deflection is the convolution integral between soil reaction field and an averaging kernel. Due to conflict between constitutive and kinematic compatibility requirements, the corresponding elastic problem of an inflected beam resting on a Wieghardt foundation is ill-posed. Modifications of the original Wieghardt model were proposed by introducing fictitious boundary concentrated forces of constitutive type, which are physically questionable, being significantly influenced on prescribed kinematic boundary conditions. Inherent difficulties and issues are overcome in the present research using a displacement-driven nonlocal integral strategy obtained by swapping the input and output fields involved in Wieghardt’s original formulation. That is, nonlocal soil reaction fields are the output of integral convolutions of beam deflection fields with an averaging kernel. Equipping the displacement-driven nonlocal integral law with the bi-exponential averaging kernel, an equivalent nonlocal differential problem, supplemented with non-standard constitutive boundary conditions involving nonlocal soil reactions, is established. As a key implication, the integrodifferential equations governing the elastostatic problem of an inflected elastic slender beam resting on a displacement-driven nonlocal integral foundation are replaced with much simpler differential equations supplemented with kinematic, static, and new constitutive boundary conditions. The proposed nonlocal approach is illustrated by examining and analytically solving exemplar problems of structural engineering. Benchmark solutions for numerical analyses are also detected.

Building premium secondary reaction field with a miniaturized capsule catalyst to realize efficient synthesis of a liquid fuel directly from syngas

2017 ◽  
Vol 7 (10) ◽  
pp. 1996-2000 ◽  
Author(s):  
Noriyuki Yamane ◽  
Yang Wang ◽  
Jie Li ◽  
Yingluo He ◽  
Peipei Zhang ◽  
...  
Keyword(s):  
Liquid Fuel ◽  
Secondary Reaction ◽  
Core Shell ◽  
Efficient Synthesis ◽  
Reaction Field

A premium secondary reaction field is built by miniaturized core–shell catalyst for synthesis of liquid fuel from syngas.

scholarly journals Synthesis of Biobased Phloretin Analogues: An Access to Antioxidant and Anti-Tyrosinase Compounds for Cosmetic Applications

Antioxidants ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 512
Author(s):  
Laurène Minsat ◽  
Cédric Peyrot ◽  
Fanny Brunissen ◽  
Jean-Hugues Renault ◽  
Florent Allais
Keyword(s):  
Natural Products ◽  
Consumer Demand ◽  
Radical Scavenging ◽  
Green Process ◽  
Direct Extraction ◽  
Low Concentration ◽  
Cosmetic Formulations ◽  
Valuable Compounds ◽  
The Stability

The current cosmetic and nutraceutical markets are characterized by a strong consumer demand for a return to natural products that are less harmful to both the consumers and the environment than current petrosourced products. Phloretin, a natural dihydrochalcone (DHC) found in apple, has been widely studied for many years and identified as a strong antioxidant and anti-tyrosinase ingredient for cosmetic formulations. Its low concentration in apples does not allow it to be obtained by direct extraction from biomass in large quantities to meet market volumes and prices. Moreover, its remarkable structure prevents its synthesis through a green process. To overcome these issues, the synthesis of phloretin analogs appears as an alternative to access valuable compounds that are potentially more active than phloretin itself. Under such considerations, 12 chalcones (CHs) and 12 dihydrochalcones (DHCs) were synthesized through a green Claisen–Schmidt condensation using bio-based reagents. In order to evaluate the potential of these molecules, radical scavenging DPPH and anti-tyrosinase tests have been conducted. Moreover, the UV filtering properties and the stability of these analogs towards UV-radiations have been evaluated. Some molecules showed competitive antioxidant and anti-tyrosinase activities regarding phloretin. Two compounds in particular showed EC50 lower than phloretin, one chalcone and one dihydrochalcone.

Selective Extraction of Lithium from a Spent Lithium Iron Phosphate Battery by Mechanochemical Solid-phase Oxidation

2021 ◽  
Author(s):  
Kang Liu ◽  
Lili Liu ◽  
Quanyin Tan ◽  
Jinhui Li
Keyword(s):  
Cathode Materials ◽  
Lithium Iron Phosphate ◽  
Solid Phase ◽  
Iron Phosphate ◽  
Selective Extraction ◽  
Green Process ◽  
Rapid Extraction ◽  
Phase Oxidation

This study proposes a green process for selective and rapid extraction of lithium from the cathode materials of spent lithium iron phosphate (LiFePO4) batteries via mechanochemical solid-phase oxidation. The advantages...

Kinetic studies on esterification of acetic acid with isopropyl alcohol in presence of novel solid catalyst

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Mallaiah Mekala
Keyword(s):  
Acetic Acid ◽  
Kinetic Model ◽  
Isopropyl Alcohol ◽  
Frequency Factor ◽  
Activation Energies ◽  
Catalyst Loading ◽  
Solid Catalyst ◽  
Heat Of Reaction ◽  
Resin Catalyst ◽  
Isopropyl Acetate

AbstractThe reaction of isopropyl alcohol with acetic acid was carried out in an isothermal batch reactor in presence of solid resin catalyst to produce isopropyl acetate and water. A novel solid resin catalyst Indion 140 was used in the present study. The temperature of reaction mixture was maintained in the range of 333.15 – 363.15 K. The effects of reaction temperature, catalyst loading, mole ratio, size of catalyst, agitation speed were investigated on acetic acid conversion. Further, pseudo-homogeneous kinetic model was developed for the catalyzed reaction. The forward reaction rate constants and activation energies were determined from the Arrhenius plot. The forward and backward activation energies are found to 53,459 J/mol and 54,748 J/mol, respectively. The heat of reaction is −1.289 kJ/mol with Indion 140 catalyst. The mathematical equation was developed for frequency factor as function of the catalyst loading and found that it follows a linear relationship between frequency factor and catalyst loading. The simulations were performed for pseudo homogeneous kinetic model and found that the model is able to predict the experimental data very well. The developed kinetic equation is useful for the simulation of a reactive distillation column for the synthesis of isopropyl acetate.

scholarly journals Green process design for reductive hydroformylation of renewable olefin cuts for drop‐in diesel fuels

ChemSusChem ◽  
2021 ◽  
Author(s):  
Sebastian Püschel ◽  
Sven Störtte ◽  
Johanna Topphoff ◽  
Andreas J. Vorholt ◽  
Walter Leitner
Keyword(s):  
Process Design ◽  
Green Process ◽  
Diesel Fuels
Sign in / Sign up

Export Citation Format

Share Document