Research Progress of Phase Transfer Catalysts Used in Oxidative Desulfurization of Fuel Oil

2020 ◽  
Vol 17 ◽  
Author(s):  
Jie Zhao ◽  
Rui Wang
Keyword(s):  
Phase Transfer ◽  
Heterogeneous Systems ◽  
Oxidative Desulfurization ◽  
Operating Conditions ◽  
Fuel Oil ◽  
Research Progress ◽  
Oil Refineries ◽  
Phase Transfer Catalysts ◽  
The Common ◽  
Fuel Industry

: The removal of sulfur compounds from fuel oil has been a major concern of the fuel industry. Hydrodesulfurization (HDS) is the most common desulfurization method currently used in oil refineries. However, HDS requires high temperature and high pressure conditions, consumption of hydrogen, and the removal effect of thiophene sulfides is not ideal. In view of defects of HDS, non-hydrodesulfurization technologies have been developed. Oxidative desulfurization (ODS) is regarded as the most potential desulfurization technology to replace HDS in industrial because of mild operating conditions and high desulfurization efficiency. However, most ODS reactions are performed in heterogeneous systems, the common problem is that the oxidant and sulfur-containing compounds cannot contact effectively. Phase Transfer Catalysts (PTCs) are a class of catalysts that can assist in the transfer of reactants, thereby increasing mass transfer and accelerating the reaction rate of the heterogeneous ODS system. In this review, we divide PTCs applied to ODS into quaternary ammonium salts PTCs, ILs PTCs, polymers PTCs, supported PTCs and reaction-controlled PTCs, and will systematically introduce and summarize the research progress of PTCs used in ODS system. It is pointed out that reaction-controlled PTCs have a broad prospect in ODS system. In addition, the synthesis and recovery of PTCs will be briefly described.

scholarly journals Oxidative Extractive Desulfurization System for Fuel Oil Using Acidic Eutectic-Based Ionic Liquid

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1050
Author(s):  
Sarrthesvaarni Rajasuriyan ◽  
Hayyiratul Fatimah Mohd Zaid ◽  
Mohd Faridzuan Majid ◽  
Raihan Mahirah Ramli ◽  
Khairulazhar Jumbri ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Removal Efficiency ◽  
Environmental Effects ◽  
Sulfur Compounds ◽  
Operating Conditions ◽  
Fuel Oil ◽  
Organosulfur Compounds ◽  
Dsc Analysis ◽  
Oil Refineries ◽  
Desulfurization Process

The biggest challenge faced in oil refineries is the removal of sulfur compounds in fuel oil. The sulfur compounds which are found in fuel oil such as gasoline and diesel, react with oxygen in the atmosphere to produce sulfur oxide (SOx) gases when combusted. These sulfur compounds produced from the reaction with oxygen in the atmosphere may result in various health problems and environmental effects. Hydrodesulfurization (HDS) is the conventional process used to remove sulfur compounds from fuel oil. However, the high operating conditions required for this process and its inefficiency in removing the organosulfur compounds turn to be the major drawbacks of this system. Researchers have also studied several alternatives to remove sulfur from fuel oil. The use of ionic liquids (ILs) has also drawn the interest of researchers to incorporate them in the desulfurization process. The environmental effects resulting from the use of these ILs can be eliminated using eutectic-based ionic liquids (EILs), which are known as greener solvents. In this research, a combination of extractive desulfurization (EDS) and oxidative desulfurization (ODS) using a photocatalyst and EIL was studied. The photocatalyst used is a pre-reported catalyst, Cu-Fe/TiO2 and the EIL were synthesized by mixing choline chloride (ChCl) with organic acids. The acids used for the EILs were propionic acid (PA) and p-toluenesulfonic acid (TSA). The EILs synthesized were characterized using thermogravimetry analyser (TGA) differential scanning calorimetry (DSC) analysis to determine the physical properties of the EILs. Based on the TGA analysis, ChCl (1): PA (3) obtained the highest thermal stability whereas, as for the DSC analysis, all synthesized EILs have a lower melting point than its pure component. Further evaluation on the best EIL for the desulfurization process was carried out in a photo-reactor under UV light in the presence of Cu-Fe/TiO2 photocatalyst and hydrogen peroxide (H2O2). Once the oxidation and extraction process were completed, the oil phase of the mixture was analyzed using high performance liquid chromatography (HPLC) to measure the sulfur removal efficiency. In terms of the desulfurization efficiency, the EIL of ChCl (1): TSA (2) showed a removal efficiency of about 99.07%.

Organic Synthesis Engineering

2001 ◽  
Author(s):  
L. K. Doraiswamy
Keyword(s):  
Organic Synthesis ◽  
Phase Transfer ◽  
Heterogeneous Systems ◽  
Process Intensification ◽  
Reaction Rates ◽  
Main Theme ◽  
Scale Production ◽  
Phase Transfer Catalysts ◽  
Industrial Scale Production

This book will formally launch "organic synthesis engineering" as a distinctive field in the armory of the reaction engineer. Its main theme revolves around two developments: catalysis and the role of process intensification in enhancing overall productivity. Each of these two subjects are becoming increasingly useful in organic synthesis engineering, especially in the production of medium and small volume chemicals and enhancing reaction rates by extending laboratory techniques, such as ultrasound, phase transfer catalysts, membrane reactor, and microwaves, to industrial scale production. This volume describes the applications of catalysis in organic synthesis and outlines different techniques of reaction rate and/or selectivity enhancement against a background of reaction engineering principles for both homogeneous and heterogeneous systems.

scholarly journals Green Process for Adipic Acid Synthesis: Oxidation by Hydrogen Peroxide in Water Micromelusions using Benzalkonium Chloride C12-14 Surfactant

2012 ◽  
Vol 10 (1) ◽  
Author(s):  
Geoffroy Lesage ◽  
Isariebel Quesada Peñate ◽  
Patrick Cognet ◽  
Martine Poux
Keyword(s):  
Hydrogen Peroxide ◽  
Adipic Acid ◽  
Phase Transfer ◽  
Industrial Process ◽  
Acid Synthesis ◽  
Operating Conditions ◽  
High Yield ◽  
Green Process ◽  
Phase Transfer Catalysts ◽  
Reaction Media

Abstract Adipic acid was synthesized by the oxidation of cyclohexene using 30% hydrogen peroxide in a microemulsion in the presence of sodium tungstate as catalyst. The proposed green process is environmentally friendly since catalyst and surfactant are recycled and pure adipic acid is produced in high yield (70% to 79%). Microemulsions are used as a “green solvent” and give a better contact between the phases. Alkyldimethylbenzylammonium chloride (C12-C14) was used as a surfactant for the generation of the microemulsion since it enables the use of harmful organic solvents and phase-transfer catalysts to be avoided. Optimised operating conditions (temperature, reaction time, separation process) have been defined and applied to evaluate the industrial practicability. The main interest of the present work is the easy recovery of pure adipic acid and the reuse of the reaction media (surfactant and catalyst). This shows promise for developing a future green industrial process that will enable greenhouse gas emissions (N2O), among others, to be reduced.

scholarly journals Improved Access to Chiral Tetranaphthoazepinium-Based Organocatalysts Using Aqueous Ammonia as Nitrogen Source

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3844 ◽  
Author(s):  
Auraya Manaprasertsak ◽  
Sorachat Tharamak ◽  
Christina Schedl ◽  
Alexander Roller ◽  
Michael Widhalm
Keyword(s):  
Nitrogen Source ◽  
Phase Transfer ◽  
Aqueous Ammonia ◽  
Economic Strategy ◽  
Tert Butyl ◽  
Phase Transfer Catalysts ◽  
Highly Efficient ◽  
Screening Experiments ◽  
The Common

The class of 3,3′-diaryl substituted tetranaphthobisazepinium bromides has found wide application as highly efficient C2-symmetrical phase-transfer catalysts (PTCs, Maruoka type catalysts). Unfortunately, the synthesis requires a large number of steps and hampers the build-up of catalyst libraries which are often desired for screening experiments. Here, we present a more economic strategy using dinaphthoazepine 7 as the common key intermediate. Only at this stage various aryl substituents are introduced, and only two individual steps are required to access target structures. This protocol was applied to synthesize ten tetranaphthobisazepinium compounds 1a–1j. Their efficiency as PTCs was tested in the asymmetric substitution of tert-butyl 2-((diphenylmethylene)amino)acetate. Enantioselectivities up to 92% have been observed with new catalysts.

Green Application of Phase-Transfer Catalysis in Oxidation: A Comprehensive Review

2020 ◽  
Vol 17 (4) ◽  
pp. 405-411
Author(s):  
Chuan-Hui Wang ◽  
Chen-Fu Liu ◽  
Guo-Wu Rao
Keyword(s):  
Organic Chemistry ◽  
Green Chemistry ◽  
Oxidation Reaction ◽  
Phase Transfer Catalysis ◽  
Phase Transfer ◽  
Important Application ◽  
Oxidation Reactions ◽  
Comprehensive Review ◽  
Phase Transfer Catalysts ◽  
Onium Salts

Oxidation reactions have emerged as one of the most versatile tools in organic chemistry. Various onium salts such as ammonium, phosphonium, arsonium, bismuthonium, tellurium have been used as phase transfer catalysts in many oxidation reactions. Certainly, considerable catalysts have been widely used in Phase-Transfer Catalysis (PTC). This review focuses on the application of PTC in various oxidation reaction. Furthermore, PTC also conforms to the concept of “Green Chemistry”. <p></p> • Oxidation has become one of the most widely used tools in organic chemistry and phase transfer catalysts has been widely used in oxidation. <p></p> • The application of phase transfer catalysts in oxidation reaction will be summarized. <p></p> • Phase transfer catalysts have important application in various oxidation reaction.

Organocatalyzed Heterocyclic Transformations In Green Media: A Review

2020 ◽  
Vol 07 ◽  
Author(s):  
Neslihan Demirbas ◽  
Ahmet Demirbas
Keyword(s):  
Hydrogen Bonding ◽  
Phase Transfer ◽  
Noncovalent Interactions ◽  
Binding Capacity ◽  
Chemical Transformations ◽  
Organic Transformations ◽  
Phase Transfer Catalysts ◽  
Waste Production ◽  
Synthetic Methodologies ◽  
Organocatalytic Reactions

Background: Since the discovery of metal-free catalysts or organocatalysts about twenty years ago, a number of small molecules with different structures have been using to accelerate organic transformations. With the development of environmental awareness, in order to obtain highly privileged scaffolds, scientists have directed their studies towards the synthetic methodologies which minimize or preferably eliminate the formation of waste, avoid from toxic solvents and reagents and use renewable starting materials as far as possible. Methods: In this connection, the organocatalytic reactions providing efficiency and selectivity for most of case have become an endless topic in organic chemistry since several advantages from both practical and environmental standpoints. Organocatalysts supplying transformation of reactants into products with the least possible waste production have been serving to the concept of green chemistry. Results and Conclusion: Organocatalysts have been classified on the basis of their binding capacity to the substrate with covalently or noncovalent interactions involving hydrogen bonding and electrostatic interaction. Diverse types of small organic compounds including proline and its derivatives, phase-transfer catalysts, (thio)urease, phosphoric acids, sulfones, N-oxides, guanidines, cinchona derivatives, aminoindanol and amino acids have been utilized as hydrogen bonding organocatalysts in different chemical transformations.

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