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You searched for: Subject "transesterification" Remove constraint Subject: "transesterification"
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1. Application of untargeted volatile profiling to investigate the fate of aroma compounds during wine oral processing

Author:
María Pérez-Jiménez; Emma Sherman; María Ángeles Pozo-Bayón; Carolina Muñoz-González; Farhana R. Pinu
Source:
Food chemistry 2023 v.403 pp. 134307
ISSN:
0308-8146
Subject:
transesterification,   etc   ; food chemistry; hydrolysis; mouth; odors; red wines; volatile compounds;     Show all 7 Subjects
Abstract:
... We employed an untargeted volatile profiling approach in combination with spit off-odorant measurement procedure to investigate the fate of aroma compounds in mouth by determining how oral processing and intrinsic biological variables influence the overall volatile composition. A red wine before and after oral processing (expectorated wine), and control samples (expectorated water) were analyzed u ...
DOI:
10.1016/j.foodchem.2022.134307

2. Waste to energy: Production of poultry-based fat biodiesel and experimental assessment of its usability on engine behaviors

Author:
A.S. El-Shafay; Ümit Ağbulut; El-Awady Attia; Kamel Lounes Touileb; M.S. Gad
Source:
Energy 2023 v.262 pp. 125457
ISSN:
0360-5442
Subject:
transesterification,   etc   ; biodiesel; chickens; combustion; diesel fuel; energy; energy use and consumption; esterification; feedstocks; heat; oils; opacity; smoke; temperature; wastes;     Show all 15 Subjects
Abstract:
... High volatility in fuel prices, energy security issues, and concerns about rising emissions have always driven researchers to search for renewable alternative fuels. Therefore, researchers have agreed on the idea that biodiesel fuels obtained from the various feedstocks have been the best alternative to conventional fuels. Accordingly, in the present research, the chicken oil biodiesel is first pr ...
DOI:
10.1016/j.energy.2022.125457

3. Converse two-way shape memory effect through a dynamic covalent network design

Author:
Guancong Chen; Jiante Dong; Xiaona Xu; Weike Zou; Binjie Jin; Wenjun Peng; Qian Zhao; Tao Xie; Ning Zheng
Source:
Journal of materials chemistry A 2022 v.10 no.19 pp. 10350-10354
ISSN:
2050-7496
Subject:
transesterification,   etc   ; catalysts; smart materials; thermosensitivity;     Show all 4 Subjects
Abstract:
... The recently emerged thermally driven two-way shape memory effect has greatly expanded the capabilities and practical potential of shape memory polymers. Without exception, its actuation direction is reflected as cooling-induced elongation and heating-induced contraction along with the programming force. In contrast to the current knowledge, we describe here a molecular mechanism to achieve an opp ...
DOI:
10.1039/d2ta01540d

4. Transcarbamoylation in Polyurethanes: Underestimated Exchange Reactions?

Author:
Camille Bakkali-Hassani; Dimitri Berne; Vincent Ladmiral; Sylvain Caillol
Source:
Macromolecules 2022 v.55 no.18 pp. 7974-7991
ISSN:
1520-5835
Subject:
transesterification,   etc   ; polyurethanes; temperature; toxicity; urethane;     Show all 5 Subjects
Abstract:
... While transesterification has been largely explored by chemists, only a few studies comparatively dealt with its “sluggish cousin”, transcarbamoylation. Originally suggested 70 years ago to explain the stress decay observed at high temperature in polyurethane chemical networks, transcarbamoylation─also called transurethanization or urethane exchange─is still underexploited in both organic and poly ...
DOI:
10.1021/acs.macromol.2c01184

5. Transesterification of Methyl-10-undecenoate and Poly(ethylene adipate) Catalyzed by (Cyclopentadienyl)titanium Trichlorides as Model Chemical Conversions of Plant Oils and Acid-, Base-Free Chemical Recycling of Aliphatic Polyesters

Author:
Kotohiro Nomura; Tomoyuki Aoki; Yuriko Ohki; Soichi Kikkawa; Seiji Yamazoe
Source:
ACS sustainable chemistry & engineering 2022 v.10 no.38 pp. 12504-12509
ISSN:
2168-0485
Subject:
transesterification,   etc   ; depolymerization; green chemistry; titanium;     Show all 4 Subjects
Abstract:
... Highly active and exclusive transesterifications of methyl 10-undecenoate with alcohols (cyclohexanemethanol, 1,4-cyclohexanedimethanol, 10-undecen-1-ol, 3-hexanol) have been demonstrated by Cp′TiCl₃ (Cp′ = Cp, C₅Me₅) at 100–120 °C. The CpTiCl₃ enabled depolymerization of poly(ethylene adipate) by the transesterification (>99% conv., 0.25–0.5 mol % Ti) at 120 °C; the depolymerization completed aft ...
DOI:
10.1021/acssuschemeng.2c04877

6. A Cation-Dependent Dual Activation Motif for Anionic Ring-Opening Polymerization of Cyclic Esters

Author:
Caleb N. Jadrich; Vince E. Pane; Binhong Lin; Gavin O. Jones; James L. Hedrick; Nathaniel H. Park; Robert M. Waymouth
Source:
Journal of the American Chemical Society 2022 v.144 no.19 pp. 8439-8443
ISSN:
1520-5126
Subject:
transesterification,   etc   ; hydrogen; lactones; organocatalysts; polymerization; urea;     Show all 6 Subjects
Abstract:
... A new organocatalyst for the ring-opening polymerization of lactones has been identified. Under the tested conditions, the anions of 2,2′-bisindole promote fast, living polymerizations (as short as 10 ms) which are selective for chain elongation over transesterification (Đ ≤ 1.1). While structurally related to (thio)urea anion catalysts, anions of 2,2′-bisindole activate the monomer via the counte ...
DOI:
10.1021/jacs.2c01436

7. Cipacinoids E–O: Eleven limonoids represent two different scaffolds from Cipadessa cinerascens

Author:
Jin-Hai Yu; Bin Zhou; Pei-Qian Wu; Qun-Fang Liu; Jian-Min Yue
Source:
Tetrahedron 2022 v.103 pp. 132566
ISSN:
0040-4020
Subject:
transesterification,   etc   ; Cipadessa baccifera; limonoids; spectral analysis;     Show all 4 Subjects
Abstract:
... Eleven new limonoids named cipacinoids E–O (1–11) including nine methyl angolensate-type limonoids (1–9) and two havanensin-type limonoids (10 and 11), as well as seven reported limonoids (12–18), were isolated from the leaves of Cipadessa cinerascens. The structures of these limonoids were identified by analyses of spectroscopic data and by using the methods of quantum-chemical calculation. Cipac ...
DOI:
10.1016/j.tet.2021.132566

8. Performance and emission analysis of diesel-fired boiler using biodiesel made from waste cooking oil

Author:
Md. Nasir Hussain; Pali Harveer Singh
Source:
Journal of Biofuels 2022 v.13 no.1 pp. 28-38
ISSN:
0976-4763
Subject:
transesterification,   etc   ; biodiesel; cost analysis; oils; viscosity;     Show all 5 Subjects
Abstract:
... In this experiment, first, the biodiesel has been produced from waste cooking oil through the process of transesterification. Then several tests like FTIR, Viscosity, calorific value, density, flash point, and fire point tests have been performed on this Bio-diesel and the results have been recorded. Then this Biodiesel has been blended with conventional diesel (D100) in the concentrations B10 (90 ...
DOI:
10.5958/0976-4763.2022.00004.6

9. B(C₆F₅)₃-Catalyzed transfer hydrogenation of esters and organic carbonates towards alcohols with ammonia borane

Author:
Xuewen Guo; Felix Unglaube; Udo Kragl; Esteban Mejía
Source:
Chemical communications 2022 v.58 no.41 pp. 6144-6147
ISSN:
1364-548X
Subject:
transesterification,   etc   ; Lewis acids; ammonia; catalysts; hydrogen; hydrogenation;     Show all 6 Subjects
Abstract:
... Herein, we report an efficient metal-free system for the transfer hydrogenation of esters and carbonates by-passing the otherwise ubiquitous formation of transesterification side-products. The Lewis acid B(C₆F₅)₃ is used as catalyst and ammonia borane as hydrogen donor. This methodology shows broad substrate scope and functional group tolerance in excellent yields at very mild conditions. ...
DOI:
10.1039/d2cc01442d

10. Critical Effects of Branch Numbers at the Cross-Link Point on the Relaxation Behaviors of Transesterification Vitrimers

Author:
Taketo Isogai; Mikihiro Hayashi
Source:
Macromolecules 2022 v.55 no.15 pp. 6661-6670
ISSN:
1520-5835
Subject:
transesterification,   etc   ; activation energy; crosslinking; stress relaxation; temperature;     Show all 5 Subjects
Abstract:
... Vitrimers are functional cross-linked materials, exhibiting reprocessability, recyclability, and healability, and thus these are expected for application as sustainable materials. The functionalities of vitrimers are attributable to their associative bond exchange mechanism that is activated at a certain high temperature. The construction of a tuning method for the bond exchange properties must be ...
DOI:
10.1021/acs.macromol.2c00560

11. Enhancing the sustainability of biodiesel fuels by inherently safer production processes

Author:
Mariasole Cipolletta; Marco D'Ambrosio; Valeria Casson Moreno; Valerio Cozzani
Source:
Journal of cleaner production 2022 v.344 pp. 131075
ISSN:
0959-6526
Subject:
transesterification,   etc   ; biodiesel; energy; industrial applications; inventories; rapeseed oil;     Show all 6 Subjects
Abstract:
... Biodiesel is an emerging green fuel that is finding increasing applications. The further improvement of the sustainability of biodiesel production processes is a key element in the energy transition scenario. Among the social pillars of sustainability, safety is a specific requirement. However, several major accidents were experienced in biodiesel facilities, involving the inventory of hazardous s ...
DOI:
10.1016/j.jclepro.2022.131075

12. A plant wide simulation of polyhydroxyalkanoate production from wastewater and its conversion to methyl crotonate

Author:
Joris Koch; Elinor Scott; Johannes Bitter; Akbar Asadi Tashvigh
Source:
Bioresource technology 2022 v.363 pp. 127994
ISSN:
0960-8524
Subject:
transesterification,   etc   ; candy; esterification; industrial wastewater; polyhydroxybutyrate; thermal degradation;     Show all 6 Subjects
Abstract:
... This work simulates the production of methyl crotonate from various industrial wastewaters. In the upstream process, wastewater is fermented into volatile fatty acids which are then converted into polyhydroxyalkanoates (PHA) by means of mixed microbial cultures. In the downstream, PHA undergoes a series of thermolysis and esterification reactions to produce methyl crotonate. The origin of the wast ...
DOI:
10.1016/j.biortech.2022.127994

13. Producing Methyl p-Coumarate from Herbaceous Lignin via a “Clip-Off” Strategy

Author:
Yuanhao Wu; Zhechao Huang; Kaiqi Lv; Yinan Rao; Zhengjian Chen; Jiaheng Zhang; Jinxing Long
Source:
Journal of agricultural and food chemistry 2022 v.70 no.18 pp. 5624-5633
ISSN:
1520-5118
Subject:
transesterification,   etc   ; bagasse; food chemistry; hydrogen; lignin; methanol; value added;     Show all 7 Subjects
Abstract:
... As the most abundant renewable aromatic resource on Earth, lignin is a preferred starting material for producing bulk chemicals via a sustainable route. In this study, we provide a novel and efficient “clip-off” approach for producing methyl p-coumarate, an important and versatile fine chemical by selective cleavage of the ester linkage in herbaceous lignin in the presence of commercial metal chlo ...
DOI:
10.1021/acs.jafc.1c08353

14. Highly efficient synthesis of unsymmetrical organic carbonates from alcohols and diethyl carbonate over mesoporous carbon-supported MgO catalysts

Author:
Jinghui Shi; He Wang; Yunzuo Cui; Chunling Liu; Chuanbi Li; He Sun; Mingjun Jia
Source:
Journal of catalysis 2022 v.411 pp. 62-71
ISSN:
0021-9517
Subject:
transesterification,   etc   ; ambient temperature; carbonates; catalysts; catalytic activity; porous media;     Show all 6 Subjects
Abstract:
... Transesterification of dialkyl carbonate with various alcohols is a very attractive route for synthesizing unsymmetrical organic carbonates. Intensive efforts have been focused on developing highly active and stable heterogeneous catalysts that can efficiently catalyze the transesterification reaction at mild conditions. In this work, the synthesis of unsymmetrical organic carbonates was conducted ...
DOI:
10.1016/j.jcat.2022.05.007

15. Environment-friendly transesterification to seawater-degradable polymers expanded: Computational construction guide to breaking points

Author:
Mateusz Pokora; Timo Rheinberger; Frederik R. Wurm; Agata Paneth; Piotr Paneth
Source:
Chemosphere 2022 v.308 pp. 136381
ISSN:
0045-6535
Subject:
transesterification,   etc   ; Lewis bases; biodegradation; carbon; microplastics; pollution; polylactic acid; seawater;     Show all 8 Subjects
Abstract:
... Marine plastic pollution caused by non-biodegradable polymers is a major worldwide concern. So-called “biodegradable” polymers should reduce plastic pollution in the environment by the safeguard of biodegradation. However, many polyesters degrade very slowly in seawater. We therefore designed a systematic library of “breaking points” that are installed into a polylactide backbone and simulated the ...
DOI:
10.1016/j.chemosphere.2022.136381

16. Simulation and economic evaluation of fuel additives production from glycerol

Author:
Mariana B. Ribeiro; Raquel M. Cavalcante; André F. Young
Source:
Renewable energy 2022 v.181 pp. 1081-1099
ISSN:
0960-1481
Subject:
transesterification,   etc   ; acetone; biodiesel; byproducts; capital; economic evaluation; ethanol; glycerol; markets;     Show all 9 Subjects
Abstract:
... Biodiesel production continuously increases. This also increases the production of glycerol, the main by-product of transesterification, whose surplus is not fully absorbed by the market. An interesting destination for glycerol is the production of additives for the biofuel itself, as a green and economical alternative to conventional additives. The objective of this work is to simulate the produc ...
DOI:
10.1016/j.renene.2021.09.123

17. Transesterification of used cooking sunflower oil catalyzed by hazelnut shell ash

Author:
Marija R. Miladinović; Jugoslav B. Krstić; Miodrag V. Zdujić; Ljiljana M. Veselinović; Djordje N. Veljović; Ivana B. Banković-Ilić; Olivera S. Stamenković; Vlada B. Veljković
Source:
Renewable energy 2022 v.183 pp. 103-113
ISSN:
0960-1481
Subject:
transesterification,   etc   ; biodiesel; catalysts; catalytic activity; hazelnuts; porosimetry; sunflower oil; triacylglycerols;     Show all 8 Subjects
Abstract:
... Hazelnut shell ash was investigated as a new base catalyst for the transesterification of used cooking sunflower oil to biodiesel. To understand its catalytic properties, the prepared ash was characterized by EDX, XRD, TGA/DTA, Hg porosimetry, N₂ physisorption, FE-SEM, and basic strength measurements. The effects of the catalyst loading in the range of 1–5% of the oil weight and the methanol-to-oi ...
DOI:
10.1016/j.renene.2021.10.071

18. Fundamental understanding of in-situ transesterification of microalgae biomass to biodiesel: A critical review

Author:
Nguyen Tien Thanh; Marhaini Mostapha; Man Kee Lam; Syukriyah Ishak; Yaleeni Kanna Dasan; Jun Wei Lim; Inn Shi Tan; Sie Yon Lau; Bridgid Lai Fui Chin; Tony Hadibarata
Source:
Energy conversion and management 2022 v.270 pp. 116212
ISSN:
0196-8904
Subject:
transesterification,   etc   ; administrative management; biodiesel; biomass; energy efficiency; microalgae; process design;     Show all 7 Subjects
Abstract:
... One-step in-situ transesterification has been recognized as an alternative approach to produce biodiesel from microalgae biomass. Based on technoeconomic perspective, in-situ transesterification of microalgae is more energy efficient than the conventional two-step process and thus economically competitive for biodiesel production. However, a comprehensive review on the effect of processing paramet ...
DOI:
10.1016/j.enconman.2022.116212

19. Geothermal solid waste derived Ni/Zeolite catalyst for waste cooking oil processing

Author:
Hantoro Satriadi; Isdayana Yogi Pratiwi; Malikhatul Khuriyah; Widayat; Hadiyanto; Jedy Prameswari
Source:
Chemosphere 2022 v.286 pp. 131618
ISSN:
0045-6535
Subject:
transesterification,   etc   ; biodiesel; catalysts; feedstocks; solid wastes; surface area; temperature; zeolites;     Show all 8 Subjects
Abstract:
... The main aim of this work was to develop a sustainable Ni/Zeolite catalyst derived from geothermal solid waste for waste cooking oil processing. The effects of catalyst concentration and operation temperature on the transesterification process for biodiesel production which used waste cooking oil as feedstock were investigated to determine the optimum biodiesel process condition. Results have show ...
DOI:
10.1016/j.chemosphere.2021.131618

20. Performance and emission characteristics of biodiesel fuel from Dunaliella tertiolecta microalgae

Author:
A. Tizvir; M.H. Shojaeefard; A. Zahedi; G.R. Molaeimanesh
Source:
Renewable energy 2022 v.182 pp. 552-561
ISSN:
0960-1481
Subject:
transesterification,   etc   ; Dunaliella tertiolecta; biodiesel; carbon dioxide; diesel fuel; microalgae; oils;     Show all 7 Subjects
Abstract:
... In this study, the performance and emission characteristics of produced biodiesel from Dunaliella tertiolecta microalgae are investigated for the first time. To achieve reliable results, all production stages including cultivation, harvesting, oil extraction, and transesterification are executed in the current study. The cetane number and heating value of the produced biodiesel from Dunaliella ter ...
DOI:
10.1016/j.renene.2021.10.018