scholarly journals Biodiesel fromCitrullus colocynthisOil: Sulfonic-Ionic Liquid-Catalyzed Esterification of a Two-Step Process

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Yasir Ali Elsheikh ◽  
Faheem Hassan Akhtar
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Sulfonic Acid ◽  
Molar Ratio ◽  
Disulfonic Acid ◽  
Hydrogen Sulfate ◽  
Citrullus Colocynthis ◽  
Step Process ◽  
Acidic Catalyst ◽  
Acidic Catalysts

Biodiesel was prepared fromCitrullus colocynthisoil (CCO) via a two-step process. The first esterification step was explored in two ionic liquids (ILs) with 1,3-disulfonic acid imidazolium hydrogen sulfate (DSIMHSO4) and 3-methyl-1-sulfonic acid imidazolium hydrogen sulfate (MSIMHSO4). Both ILs appeared to be good candidates to replace hazardous acidic catalyst due to their exceptional properties. However, the two sulfonic chains existing in DSIMHSO4were found to increase the acidity to the IL than the single sulfonic chain in MSIMHSO4. Based on the results, 3.6 wt% of DSIMHSO4, methanol/CCO molar ratio of 12 : 1, and 150°C offered a final FFA conversion of 95.4% within 105 min. A 98.2% was produced via second KOH-catalyzed step in 1.0%, 6 : 1 molar ratio, 600 rpm, and 60°C for 50 min. This new two-step catalyzed process could solve the corrosion and environmental problems associated with the current acidic catalysts.

scholarly journals Production of 5-Hydroxymethylfurfural from pine wood via biorefinery technologies based on fractionation and reaction in ionic liquids

BioResources ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. 4733-4747
Author(s):  
Lucía Penín ◽  
Susana Peleteiro ◽  
Sandra Rivas ◽  
Valentín Santos ◽  
Juan Carlos Parajó
Keyword(s):  
Ionic Liquid ◽  
Acetic Acid ◽  
Ionic Liquids ◽  
Solid Phase ◽  
Selective Separation ◽  
Hydrogen Sulfate ◽  
Efficient Utilization ◽  
Pine Wood ◽  
Acidic Catalysts ◽  
Reaction Media

Pine wood is mainly composed of extractives, lignin, cellulose, and hemicelluloses (which include pentosans and hexosans). In the scope of biorefineries, the utilization of pine wood entails the selective separation of its major components. A sequence of aqueous and delignification treatments enables the selective separation of hemicelluloses (as soluble products from the aqueous fractionation step), lignin (as soluble products from the delignification stage), and cellulose (accumulated in the solid phase leaving the delignification stage). Delignification was done in media containing acetic acid or the ionic liquid 1-butyl-3-methylimidazolium hydrogen sulfate. Both the soluble hemicellulose-derived saccharides and the cellulose-containing solids were found to be suitable substrates for 5-hydroxymethylfurfural production in reaction media containing the ionic liquid 1-butyl-3-methylimidazolium chloride in the presence of Brønsted and/or Lewis acidic catalysts. The processing schemes considered in this work allowed an efficient utilization of the feedstock using environmentally friendly technologies.

N,N,N′,N′-Tetramethylethylene-diaminium-N,N′-disulfonic acid trifluoroacetate and pyridinium-N-sulfonic acid hydrogen sulfate as highly effective dual-functional catalysts for the preparation of N,N′-alkylidene bisamides

2019 ◽  
Vol 74 (9) ◽  
pp. 641-647 ◽  
Author(s):  
Zahra Kordrostami ◽  
Abdolkarim Zare ◽  
Mostafa Karami
Keyword(s):  
Ionic Liquids ◽  
Sulfonic Acid ◽  
Reaction Times ◽  
Solvent Free ◽  
Disulfonic Acid ◽  
Hydrogen Sulfate ◽  
Reaction Conditions ◽  
Dual Functional ◽  
Solvent Free Conditions ◽  
Acidic Ionic Liquids

AbstractIn this research, Brønsted-acidic ionic liquids N,N,N′,N′-tetramethylethylene-diaminium-N,N′-disulfonic acid trifluoroacetate ([TMEDSA][TFA]2) and pyridinium-N-sulfonic acid hydrogen sulfate ([Py-SO3H][HSO4]) have been introduced as dual-functional catalysts for the green, simple and effective preparation of N,N′-alkylidene bisamides by the reaction of primary amides (2 eq.) with arylaldehydes (1 eq.) under solvent-free conditions. The reaction results and conditions of the catalysts have been compared with the previously reported ones. [TMEDSA][TFA]2 and [Py-SO3H][HSO4] were superior to the previously reported catalysts in terms of two or more of these factors: reaction times (10–45 min), yields (86–98%), temperature and the reaction conditions. Additionally, a plausible and attractive mechanism based on dual functionality of the catalysts has been proposed.

scholarly journals Zinc Acetate Immobilized on Mesoporous Materials by Acetate Ionic Liquids as Catalysts for Vinyl Acetate Synthesis

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Hang Xu ◽  
Tianlong Yu ◽  
Mei Li
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Vinyl Acetate ◽  
Silica Gel ◽  
Catalyst Activity ◽  
Catalyst Layer ◽  
Space Velocity ◽  
Molar Ratio ◽  
Vinyl Acetate Monomer ◽  
Adsorption Desorption

Ionic liquid containing active ingredient Zn(CH3COO)2was loaded in mesoporous silica gel to form supported ionic liquids catalyst (SILC) which was used to synthesize vinyl acetate monomer (VAM). SILC was characterized by1HNMR, FT-IR, TGA, BET, and N2adsorption/desorption and the acetylene method was used to evaluate SILC catalytic activity and stability in fixed reactor. The result shows that 1-allyl-3-acetic ether imidazole acetate ionic liquid is successfully fixed within mesoporous channel of silica gel. The average thickness of ionic liquid catalyst layer is about 1.05 nm. When the catalytic temperature is 195°C, the acetic acid (HAc) conversion is 10.9% with 1.1 g vinyl acetate yield and 98% vinyl acetate (VAc) selectivity. The HAc conversion is increased by rise of catalytic temperature and molar ratio of C2H2 : HAc and decreased by mass space velocity (WHSV). The catalyst activity is not significantly reduced within 7 days and VAc selectivity has a slight decrease.

Synthesis and Characterization of Super-Molecular Ionic Liquids

2011 ◽  
Vol 197-198 ◽  
pp. 906-910
Author(s):  
Hui Ru Liu ◽  
Li Qiang Lv ◽  
Xing Chen Zhang
Keyword(s):  
Ionic Liquid ◽  
Ionic Liquids ◽  
Melting Point ◽  
Quantum Chemical ◽  
Organic Molecules ◽  
Raw Materials ◽  
Ammonium Thiocyanate ◽  
Molar Ratio ◽  
Molecular Ion

This study concerned a novel super-molecular ionic liquid synthesized by ammonium thiocyanate and caprolactam. The physical characters such as melting point and electric conductivity were investigated. Results showed that the melting point is -12.2°C at the molar ratio of 3:1 (caprolactam/ammonium thiocyanate), which is much lower than raw materials. The electric conductivities of synthesized ionic liquids were close to that of imidazole ILs. The structure of ionic liquid was characterized by IR,1HNMR and quantum chemical calculations. It was shown that the NH4+cation connected with caprolactam organic molecules by hydrogen bonds, leading to the forming of a super-molecular ion. The electrostatic attraction of super-molecular ion with anion was decreased because of the larger volume of super-molecular ion than original cation, thus the melting point decreased. The key properties that distinguish super-molecular ionic liquid from other ILs were the presence of supermolecular ion, which can be used to build up a hydrogen-bonded network. This type ion liquid was named as super-molecular ion liquid.

1,3-Disulfonic acid imidazolium hydrogen sulfate: a reusable and efficient ionic liquid for the one-pot multi-component synthesis of pyrimido[4,5-b]quinoline derivatives

RSC Advances ◽  
2015 ◽  
Vol 5 (30) ◽  
pp. 23586-23590 ◽  
Author(s):  
Kamal Mohammadi ◽  
Farhad Shirini ◽  
Asieh Yahyazadeh
Keyword(s):  
Ionic Liquid ◽  
Reaction Times ◽  
Disulfonic Acid ◽  
Quinoline Derivatives ◽  
Hydrogen Sulfate ◽  
Efficient Synthesis ◽  
One Pot ◽  
The One

1,3-Disulfonic acid imidazolium hydrogen sulfate (DSIMHS) has been used for the simple and efficient synthesis of pyrimido[4,5-b]quinoline derivatives. The procedure gave the products in excellent yields in very short reaction times.

scholarly journals PREPARATION OF [AcMI] HSO4 AND USING AS CATALYST FOR ESTERIFICATION

2011 ◽  
Vol 14 (4) ◽  
pp. 61-73
Author(s):  
Thu Ngoc Ha Le ◽  
Thach Ngoc Le
Keyword(s):  
Ionic Liquid ◽  
Chloroacetic Acid ◽  
Molar Ratio ◽  
Hydrogen Sulfate ◽  
Reaction Conditions ◽  
Brønsted Acidic Ionic Liquid ◽  
Acidic Sites ◽  
Concentrated Sulfuric Acid ◽  
Zwitter Ion ◽  
Optimal Reaction

New Bronsted acidic ionic liquid, 1-carboxymethyl-3-methylimidazolium hydrogen sulfate [AcMI]HSO4, has two acidic sites -COOH and HSO4 -. It has been synthesized by three steps. First, 1-carboxymethyl-3-methylimidazolium chloride [AcMI]Cl was prepared by alkylation of 1- methylimidazole with chloroacetic acid (molar ratio is 1.5:1) under microwave irradiation in 6 min (84 % isolated yield). Then, zwitter ion 1-carboxylatmethyl-3-methylimidazolium was obtained by using Ag2O to remove ion chloride Cl- from [AcMI]Cl. At last, concentrated sulfuric acid (98 %) was added into zwitter ion to give 1-carboxymethyl-3-methylimidazolium hydrogen sulfate (yield 96 %). This ionic liquid used as a recyclabe catalyst for the esterification of isopropanol and chloroacetic acid. The optimal reaction conditions were obtained as follows: isopropanol: chloroacetic acid:[AcMI]HSO4 are 1.3:1:0.2, reaction time for 10 min at 60 oC under microvave irradiation. The yield of isopropyl chloroacetate was 86 %. This ionic liquid was removed from ester easily, recovered and recycled without loss of activity.

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