scholarly journals Selective Hydrogenation of Stearic Acid to 1-Octadecanol Using Bimetallic Palladium-Tin Supported on Carbon Catalysts at Mild Reaction Conditions

2021 ◽  
Vol 16 (4) ◽  
pp. 888-903
Author(s):  
Rodiansono Rodiansono ◽  
Elisa Hayati ◽  
Atina Sabila Azzahra ◽  
Maria Dewi Astuti ◽  
Kamilia Mustikasari ◽  
...  
Keyword(s):  
Stearic Acid ◽  
High Selectivity ◽  
Xrd Analysis ◽  
Molar Ratio ◽  
Stearyl Alcohol ◽  
Reaction Conditions ◽  
Water Solvent ◽  
Loading Amount ◽  
Carbon Catalysts ◽  
Bimetallic Palladium

Bimetallic palladium-tin catalysts supported on microporous carbon (denoted as Pd-Sn(x)/C, loading amount of Pd = 5 wt% and x = Pd/Sn molar ratio; c.a. 3.0; 1.5; and 1.0) showed high selectivity in the hydrogenation of stearic acid towards 1-octadecanol (stearyl alcohol) under mild reaction conditions. Pd-Sn(x)/C catalysts were synthesized via the hydrothermal method at temperature of 150 °C for 24 h, and reduced with H2 at 400 °C for 3 h. Pd-Sn(1.5)/C catalyst exhibited the highest yield of stearyl alcohol (1-octadecanol) (up to 73.2%) at 100% conversion of stearic acid at temperature 240 °C, initial H2 pressure of 3.0 MPa, a reaction time of 13 h, and in 2-propanol/water solvent. The high selectivity of alcohols over Pd-Sn(1.5)/C catalyst can be attributed to the formation of bimetallic Pd-Sn alloy phases (e.g. Pd3Sn and Pd3Sn2) as obviously depicted by XRD analysis. The presence of co-promotor Sn and the formation of bimetallic may play a pivotal role in the high selectivity of 1-octadecanol. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

scholarly journals The Promotion Effect of Cu on the Pd/C Catalyst in the Chemoselective Hydrogenation of Unsaturated Carbonyl Compounds

2021 ◽  
Vol 16 (2) ◽  
pp. 267-279
Author(s):  
Kamilia Mustikasari ◽  
Rodiansono Rodiansono ◽  
Maria Dewi Astuti ◽  
Sadang Husain ◽  
Sutomo Sutomo
Keyword(s):  
Carbonyl Compounds ◽  
Molar Ratio ◽  
Hydrothermal Route ◽  
Reaction Conditions ◽  
High Productivity ◽  
Air Atmosphere ◽  
Cu Alloy ◽  
Chemoselective Hydrogenation ◽  
Bimetallic Palladium ◽  
Open Access Article

Highly efficient and selective hydrogenation of a,b-unsaturated carbonyl compounds to unsaturated alcohol using bimetallic palladium-copper supported on carbon (denoted as Pd-Cu(3.0)/C; 3.0 is Pd/Cu molar ratio) catalyst is demonstrated. Pd-Cu(3.0)/C catalyst was prepared via a simple hydrothermal route under air atmosphere at 150 °C for 24 h followed by reduction with hydrogen at 400°C for 1.5 h. The chemoselective hydrogenation of typical a,b-unsaturated carbonyl ketone (2-cyclohexene-1-one) and aldehyde (trans-2-hexenaldehyde), and chemoselective hydrogenation of FFald and (E)-non-3-en-2-one mixture demonstrated high productivity, leading to high selectivity of unsaturated alcohols. The presence of bimetallic Pd-Cu alloy phase with relatively high H2 uptakes was observed, enabling to preferentially hydrogenate C=O rather than to C=C bonds under mild reaction conditions. Pd-Cu(3.0)/C catalyst was found to stable and reusable for at least four reaction runs and the activity and selectivity of the catalyst can be restored to the original after rejuvenation with H2 at 400 °C for 1.5 h. Copyright © 2021 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0). 

Sulfonyl Radical Triggered Selective Iodosulfonylation and Bicycli-zations of 1,6-Dienes

2021 ◽  
Author(s):  
Shi-Ping Wu ◽  
Dong-Kai Wang ◽  
Qing-Qing Kang ◽  
Guo-Ping Ge ◽  
Hongxing Zheng ◽  
...  
Keyword(s):  
Functional Group ◽  
High Selectivity ◽  
Reaction Conditions ◽  
First Time

A novel sulfonyl radical triggered selective iodosulfonylation and bicyclizations of 1,6-dienes has been described for the first time. High selectivity and efficiency, mild reaction conditions, excellent functional group compatibility, and...

scholarly journals Ring-Opening Copolymerization of Cyclohexene Oxide and Cyclic Anhydrides Catalyzed by Bimetallic Scorpionate Zinc Catalysts

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1651
Author(s):  
Felipe de la Cruz-Martínez ◽  
Marc Martínez de Sarasa Buchaca ◽  
Almudena del Campo-Balguerías ◽  
Juan Fernández-Baeza ◽  
Luis F. Sánchez-Barba ◽  
...  
Keyword(s):  
Catalytic Activity ◽  
Reaction Mechanism ◽  
Catalytic System ◽  
Phthalic Anhydride ◽  
Ring Opening ◽  
High Selectivity ◽  
Zinc Complexes ◽  
Cyclohexene Oxide ◽  
Reaction Conditions ◽  
Cyclic Anhydrides

The catalytic activity and high selectivity reported by bimetallic heteroscorpionate acetate zinc complexes in ring-opening copolymerization (ROCOP) reactions involving CO2 as substrate encouraged us to expand their use as catalysts for ROCOP of cyclohexene oxide (CHO) and cyclic anhydrides. Among the catalysts tested for the ROCOP of CHO and phthalic anhydride at different reaction conditions, the most active catalytic system was the combination of complex 3 with bis(triphenylphosphine)iminium as cocatalyst in toluene at 80 °C. Once the optimal catalytic system was determined, the scope in terms of other cyclic anhydrides was broadened. The catalytic system was capable of copolymerizing selectively and efficiently CHO with phthalic, maleic, succinic and naphthalic anhydrides to afford the corresponding polyester materials. The polyesters obtained were characterized by spectroscopic, spectrometric, and calorimetric techniques. Finally, the reaction mechanism of the catalytic system was proposed based on stoichiometric reactions.

Preparation and thermostability of hydrophobic modified nanocrystalline cellulose

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Junliang Lu ◽  
Jinyan Lang ◽  
Na Wang ◽  
Xinhui Wang ◽  
Ping Lan ◽  
...  
Keyword(s):  
Stearic Acid ◽  
Palmitic Acid ◽  
Lauric Acid ◽  
Morphological Structure ◽  
Strong Stability ◽  
Nanocrystalline Cellulose ◽  
Original Structure ◽  
Optimal Conditions ◽  
Reaction Conditions ◽  
New Approach

Abstract In this paper, we provide a new approach for the anionic modification and functional application of nanocellulose. The nanocrystalline cellulose (NCC) is prepared from microcrystalline cellulose (MCC) and modified by fatty acids (lauric acid, palmitic acid and stearic acid). Ammonium ceric sulfate or hydrogen peroxide/ferrous sulfate being used as an initiator, three kinds of modified nanocrystalline cellulose (MNCC) can be synthesized at low temperature. The terminology for these MNCC is L-MNCC (NCC modified by lauric acid), P-MNCC (NCC modified by palmitic acid) and S-MNCC (NCC modified by stearic acid). Compared with those existing synthesized methods, the reaction condition is mild, and the modified products show strong stability. It can be seen from morphological structure analysis and reaction conditions analysis of MNCC that the original structure of cellulose is changed slightly. And the optimal conditions for preparing MNCC are obtained. The best yields of L-MNCC, P-MNCC and S-MNCC are 54.2 %, 20.9 % and 14.5 %, respectively.

Study on the Synthesis of Isoamyl Acetate Catalyzed by Strong Acidic Cation Exchange Resin

2011 ◽  
Vol 396-398 ◽  
pp. 2411-2415 ◽  
Author(s):  
Ping Lan ◽  
Li Hong Lan ◽  
Tao Xie ◽  
An Ping Liao
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Cation Exchanger ◽  
Cation Exchange Resin ◽  
Isoamyl Acetate ◽  
Molar Ratio ◽  
Esterification Reaction ◽  
Reaction Conditions ◽  
Optimum Reaction

Isoamyl acetate was synthesized from isoamylol and glacial acetic acid with strong acidic cation exchanger as catalyst. The effects of reaction conditions such as acid-alcohol ratio, reaction time, catalyst dosage to esterification reaction have been investigated and the optimum reaction conditions can be concluded as: the molar ratio of acetic acid to isoamylol 0.8:1, reaction time 2h, 25 % of catalyst (quality of acetic acid as benchmark). The conversion rate can reach up to 75.46%. The catalytic ability didn’t reduce significantly after reusing 10 times and the results showed that the catalyst exhibited preferably catalytic activity and reusability.

Optimization of biodiesel synthesis under simultaneous ultrasound-microwave irradiation using response surface methodology (RSM)

2015 ◽  
Vol 4 (4) ◽  
Author(s):  
Seyed Mohammad Safieddin Ardebili ◽  
Teymor Tavakoli Hashjin ◽  
Barat Ghobadian ◽  
Gholamhasan Najafi ◽  
Stefano Mantegna ◽  
...  
Keyword(s):  
Response Surface Methodology ◽  
Microwave Irradiation ◽  
Response Surface ◽  
Palm Oil ◽  
Catalyst Concentration ◽  
Irradiation Time ◽  
Operating Conditions ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Biodiesel Synthesis

AbstractThis work investigates the effect of simultaneous ultrasound-microwave irradiation on palm oil transesterification and uncovers optimal operating conditions. Response surface methodology (RSM) has been used to analyze the influence of reaction conditions, including methanol/palm oil molar ratio, catalyst concentration, reaction temperature and irradiation time on biodiesel yield. RSM analyses indicate 136 s and 129 s as the optimal sonication and microwave irradiation times, respectively. Optimized parameters for full conversion (97.53%) are 1.09% catalyst concentration and a 7:3.1 methanol/oil molar ratio at 58.4°C. Simultaneous ultrasound-microwave irradiation dramatically accelerates the palm oil transesterification reaction. Pure biodiesel was obtained after only 2.2 min while the conventional method requires about 1 h.

Lipase-Catalyzed Acyl-L-Carnitines Synthesis in [Bmim]PF6 Ionic Liquid

2009 ◽  
Vol 5 (1) ◽  
Author(s):  
Jin-qiang Tian ◽  
Qiang Wang ◽  
Zhong-yuan Zhang
Keyword(s):  
Ionic Liquid ◽  
Lipase Activity ◽  
Molecular Sieves ◽  
Reaction Medium ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Optimal Reaction ◽  
Better Than

In order to significantly improve the biosynthesis of acyl-L-carnitines catalyzed by lipase, there must be an efficient and suitable reaction medium that is not only polar but also hydrophobic. [Bmim]PF6, which satisfies the above two requirements, was applied as the medium. The optimal reaction conditions were: for isovaleryl-L-carnitine, 0.22aW, 200mg molecular sieves, 60ºC, 4:1 of molar ratio (fatty acid:L-carnitine), 150rpm and 60h; for octanoyl-L-carnitine and palmitoyl-L-carnitine, 0.22aW, 250 mg molecular sieves, 5:1 of molar ratio (fatty acid:L-carnitine), 200rpm, 48h, 60ºC (octanoyl-L-carnitine) and 65ºC (palmitoyl-L-carnitine). Their overall yields could reach 59.14%, 90.79% and 98.03%, respectively. The yields of isovaleryl-L-carnitine, octanoyl-L-carnitine and palmitoyl-L-carnitine in [Bmim]PF6 were 16.21%, 73.67% and 44.22 % more than those in acetonitrile, respectively. [Bmim]PF6 as the medium was better than acetonitrile. It could not only enhance the yields of acyl-L-carnitines, but also protect the lipase activity.

scholarly journals USE OF CERAMIC MATERIAL (CEMENT CLINKER) FOR THE PRODUCTION OF BIODIESEL

2013 ◽  
Vol 22 ◽  
pp. 71-78
Author(s):  
SUNNY SONI ◽  
MADHU AGARWAL
Keyword(s):  
Soybean Oil ◽  
Edible Oils ◽  
Methyl Esters ◽  
Catalytic Performance ◽  
Cement Clinker ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Rural Economic Development ◽  
Additional Demand ◽  
Biodiesel Fuels

Biodiesel is a renewable liquid fuel made from natural, renewable biological sources such as edible and non edible oils. Over the last years, biodiesel has gained more market due to its benefits and because it appears as the natural substitute for diesel. Reasons for growing interest in biodiesel include its potential for reducing noxious emissions, potential contributions to rural economic development, as an additional demand center for agricultural commodities, and as a way to reduce reliance on foreign oil. Biodiesel was prepared from soybean oil by transesterification with methanol in the presence of cement clinker. Cement clinker was examined as a catalyst for a conversion of soybean oil to fatty acid methyl esters (FAMEs). It can be a promising heterogeneous catalyst for the production of biodiesel fuels from soybean oil because of high activity in the conversion and no leaching in the transesterification reaction. The reaction conditions were optimized. A study for optimizing the reaction parameters such as the reaction temperature, and reaction time, was carried out. The catalyst cement clinker composition was characterized by XRF. The results demonstrate that the cement clinker shows high catalytic performance & it was found that the yield of biodiesel can reach as high as 84.52% after 1 h reaction at 65°C, with a 6:1 molar ratio of methanol to oil, 21 wt% KOH/cement clinker as catalyst.

Synergistic effect of co-reactant promotes one-step oxidation of cyclohexane into adipic acid catalyzed by manganese porphyrins

2015 ◽  
Vol 93 (7) ◽  
pp. 696-701 ◽  
Author(s):  
Hui Li ◽  
Yuanbin She ◽  
Haiyan Fu ◽  
Meijuan Cao ◽  
Jing Wang ◽  
...  
Keyword(s):  
Synergistic Effect ◽  
Co Oxidation ◽  
Adipic Acid ◽  
Molar Ratio ◽  
Reaction Conditions ◽  
Catalyst Structure ◽  
Manganese Porphyrins ◽  
Co Oxidation Reaction ◽  
One Step ◽  
Acid Catalyzed

The synergistic effect of cyclohexane and cyclohexanone promoted synthesis of adipic acid catalyzed by [MnIIIT(p-Cl)PP]Cl with cyclohexane and cyclohexanone as co-reactants. The results showed that the conversions of cyclohexane and cyclohexanone were significantly enhanced because of the cyclohexanone synergistic effect, and the higher selectivity to adipic acid was obtained with dioxygen as an oxidant. The studies indicated that the co-oxidation of cyclohexane and cyclohexanone was influenced by the initial molar ratio of cyclohexanone and cyclohexane, catalyst structure, catalyst concentrations, and reaction conditions. The preliminary mechanism of the co-oxidation reaction of cyclohexane and cyclohexanone using [MnIIIT(p-Cl)PP]Cl as the catalyst was proposed.

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