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1. Amine-promoted Ru1/Fe3O4 encapsulated in hollow periodic mesoporousorganosilica sphere as a highly selective and stable catalyst for aqueous levulinic acid hydrogenation

Author:
Yang, Ying; Yang, Feng; Wang, Hai; Zhou, Biao; Hao, Shijie
Source:
Journal of colloid and interface science 2021 v.581 pp. 167-176
ISSN:
0021-9797
Subject:
levulinic acid,   etc   ; 1,6-hexanediamine; catalysts; catalytic activity; encapsulation; fuels; hydrogenation; hydrophobicity; iron oxides; lactones; liquids; oxygen; pH; porosity; ruthenium;     Show all 15 Subjects
Abstract:
... It is of great importance to develop selective and stable metal catalysts for the aqueous levulinic acid hydrogenation, yet challenging. Herein, we report a yolk-structured sing atom catalyst (SAC) with amine-modified Ru₁/Fe₃O₄ core and periodic mesoporousorganosilica (PMO) shell, synthesized by a core–shell dual stabilization strategy. The Ru single atoms (0.76 wt%) are inserted into the oxygen v ...
DOI:
10.1016/j.jcis.2020.07.114

2. Pre-harvest treatment for reduction of foodborne pathogens and microbial load on tomatoes

Author:
Zhao, Tong; Ji, Pingsheng; Kumar, Govindaraj Dev
Source:
Food control 2021 v.119 pp. 107469
ISSN:
0956-7135
Subject:
levulinic acid,   etc   ; Escherichia coli O157; Listeria monocytogenes; Salmonella; chlorine; coliform bacteria; food pathogens; food safety; fruits; microbial load; population; preharvest treatment; sampling; sodium dodecyl sulfate; tomatoes; water;     Show all 16 Subjects
Abstract:
... A new bactericide comprised of two chemicals, levulinic acid and sodium dodecyl sulfate (SDS), was evaluated for its efficacy on tomatoes to reduce contamination by foodborne pathogens at pre-harvest stage. Two approaches, one as prevention and the other as the treatment, were compared on Salmonella, Shiga toxin-producing Escherichia coli (STEC), and Listeria monocytogenes contaminated tomato plan ...
DOI:
10.1016/j.foodcont.2020.107469

3. Ethyl levulinate synthesis from biomass derivative chemicals using iron doped sulfonated carbon cryogel catalyst

Author:
Nazreen Wan Ahmad, Wan Amri; Zainol, Muzakkir Mohammad; Asmadi, Mohd; Iskandar, Persia; Wan Ahmad, Wan Amri Nazreen; Amin, Nor Aishah Saidina; Hoe, Tie Teck
Source:
Journal of cleaner production 2021 v.281 pp. 124686
ISSN:
0959-6526
Subject:
levulinic acid,   etc   ; Fourier transform infrared spectroscopy; X-ray diffraction; biofuels; biomass; carbohydrates; carbon; catalysts; catalytic activity; cryogels; energy-dispersive X-ray analysis; ethanol; ethanolysis; furfural; furfuryl alcohol; iron; lactones; scanning electron microscopy; synthesis; temperature; thermogravimetry; urea;     Show all 22 Subjects
Abstract:
... Biomass-derived intermediate chemicals, such as furfuryl alcohol (FA) and levulinic acid (LA) are feeds for ethanolysis reaction to produce ethyl levulinate (EL). EL is a promising chemical that can be used as a biofuel additive and precursor for chemical synthesis, such as γ-valerolactone. The present study conducted the ethanolysis of FA and LA using modified carbon cryogel as heterogeneous cata ...
DOI:
10.1016/j.jclepro.2020.124686

4. A practical and concise homogeneous nickel catalyst for efficient solvent-free synthesis of γ-valerolactone

Author:
Zada, Bakht; Zhu, Rui; Wang, Bing; Liu, Jiao; Deng, Jin; Fu, Yao
Source:
Green chemistry 2020 v.22 no.11 pp. 3427-3432
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; catalysts; green chemistry; hydrogen; lactones; nickel;     Show all 6 Subjects
Abstract:
... Here, we report an inexpensive nickel-phosphine complex that can catalyse neat levulinic acid (LA) to γ-valerolactone (GVL) without additive at 1 atm H₂, and the catalyst can be reduced to 0.01 mol% at 30 atm. 5.8 kg LA was successfully converted to GVL in a yield of 94% with 0.1 mol% catalyst. DFT calculations and in situ APXPS indicate that L–Ni⁺–H species are the key active intermediates. ...
DOI:
10.1039/d0gc00763c

5. Cyclodextrins: from solute to solvent

Author:
El Achkar, Tracy; Moufawad, Tarek; Ruellan, Steven; Landy, David; Greige-Gerges, Hélène; Fourmentin, Sophie
Source:
Chemical communications 2020 v.56 no.23 pp. 3385-3388
ISSN:
1364-548X
Subject:
levulinic acid,   etc   ; chemical reactions; cyclodextrins; melting; mixing; solutes; solvents;     Show all 7 Subjects
Abstract:
... A supramolecular solvent based on cyclodextrin (CD) is presented here for the first time. Indeed, a low melting mixture was obtained by mixing levulinic acid and a CD derivative, which retained its inclusion ability in the resulting solvent. This new system gives rise to a new family of solvents that could be called SUPRADES (supramolecular deep eutectic solvents). ...
DOI:
10.1039/d0cc00460j

6. Esterification of levulinic acid into n-butyl levulinate catalyzed by sulfonic acid-functionalized lignin-montmorillonite complex

Author:
Zhao, Wenguang; Ding, Hui; Zhu, Jie; Liu, Xianxiang; Xu, Qiong; Yin, Dulin
Source:
Journal of bioresources and bioproducts 2020 v.5 no.4 pp. 291-299
ISSN:
2369-9698
Subject:
levulinic acid,   etc   ; alcohols; biobased products; catalysts; catalytic activity; esterification; nuclear magnetic resonance spectroscopy; water treatment;     Show all 8 Subjects
Abstract:
... In this study, sulfonic acid-functionalized lignin-montmorillonite complex (LMT-SO₃H) was prepared and employed as an efficient heterogeneous catalyst for the esterification of levulinic acid (LA) into n-butyl levulinate (BL). An intermediate pseudo-butyl levulinate (p-BL) was determined by distilled water treatment and nuclear magnetic resonance (NMR) analysis, and a possible mechanism for the es ...
DOI:
10.1016/j.jobab.2020.10.008

7. Production of fermentable sugars from Chlorella sp. by solid-acid catalyst

Author:
Jeong, Gwi-Taek; Kim, Sung-Koo; Oh, Baek-Rock
Source:
Algal research 2020 v.51 pp. 102044
ISSN:
2211-9264
Subject:
levulinic acid,   etc   ; Chlorella; biomass; byproducts; catalysts; design; experimental design; hydrolysis; microalgae; research; sugars; temperature;     Show all 12 Subjects
Abstract:
... The hydrolysis of microalgae Chlorella sp. via a solid acid catalyst was conducted in order to obtain fermentable sugars. To optimize the hydrolysis conditions, Box-Behnken design was used to construct the experimental setup. Results show that the highest fermentable sugar yield of 50.4% (25.2 g/L) was achieved using a reaction composed of 5% biomass and 40% solid acid catalyst loading (based on b ...
DOI:
10.1016/j.algal.2020.102044

8. Stable yolk-structured catalysts towards aqueous levulinic acid hydrogenation within a single Ru nanoparticle anchored inside the mesoporous shell of hollow carbon spheres

Author:
Yang, Ying; Zhang, Suoying; Gu, Lin; Shao, Shuai; Li, Wei; Zeng, Dehong; Yang, Feng; Hao, Shijie
Source:
Journal of colloid and interface science 2020 v.576 pp. 394-403
ISSN:
0021-9797
Subject:
levulinic acid,   etc   ; carbon; encapsulation; hydrogenation; lactones; leaching; nanocatalysts; nanoparticles; nanospheres; oxidation; porosity; porous media; ruthenium;     Show all 13 Subjects
Abstract:
... To well address the problem of low stability for Ru-based catalysts against sintering and leaching during synthesis and aqueous levulinic acid (LA) hydrogenation to γ-valerolactone (GVL), herein we demonstrate an “inside-to-outside” synthetic strategy for robust yolk-structured nanospheres within a single Ru nanoparticle (NP, 4.2 nm) anchored inside the mesoporous shell (pore size, 4.0 nm), denote ...
DOI:
10.1016/j.jcis.2020.05.039

9. Scalable synthesis and polymerisation of a β-angelica lactone derived monomer

Author:
Dell'Acqua, Andrea; Stadler, Bernhard M.; Kirchhecker, Sarah; Tin, Sergey; de Vries, Johannes G.
Source:
Green chemistry 2020 v.22 no.16 pp. 5267-5273
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; catalysts; catalytic activity; cycloaddition reactions; green chemistry; isomerization; lactones; polymerization; polymers; terpenoids;     Show all 10 Subjects
Abstract:
... Bio-based levulinic acid is easily ring-closed to α-angelica lactone (α-AL). α-AL can be isomerized to the conjugated β-AL under the influence of base, but since this is an equilibrium mixture it is very hard to devise a scalable process that would give pure β-AL. This problem was circumvented by distilling the equilibrium mixture to obtain a 90 : 10 mixture of β- and α-AL in 88% yield. This mixtu ...
DOI:
10.1039/d0gc00338g

10. Strategy for biological co-production of levulinic acid and polyhydroxyalkanoates by using mixed microbial cultures fed with synthetic hemicellulose hydrolysate

Author:
Pinto-Ibieta, F.; Cea, M.; Cabrera, F.; Abanto, M.; Felissia, F.E.; Area, M.C.; Ciudad, G.
Source:
Bioresource technology 2020 v.309 pp. 123323
ISSN:
0960-8524
Subject:
levulinic acid,   etc   ; acetates; batch systems; biological production; carbon; hemicellulose; hydrolysates; microorganisms; pentoses; polyhydroxyalkanoates; value added;     Show all 11 Subjects
Abstract:
... Hemicellulose hydrolysates (HH), which could be an interesting carbon source to feed mixed microbial cultures (MMC) able to accumulate high value-added compounds. This research focused on the evaluation of a culture strategy to achieve the simultaneous biological production of Levulinic Acid (LA) and Polyhydroxyalcanoates (PHA) by MMC fed with a synthetic HH (SHH). The culture strategy involves th ...
DOI:
10.1016/j.biortech.2020.123323

11. Microwave Irradiation-Enhanced Catalytic Transfer Hydrogenation of Levulinic Acid to γ-Valerolactone Using Ruthenium: A Comparative Study with Conventional Heating Processes

Author:
Yun, Wan-Chu; Lin, Tien-Yu; Chiu, Hsing-Yi; Lin, Kun-Yi Andrew
Source:
Waste and biomass valorization 2020 v.11 no.6 pp. 2783-2793
ISSN:
1877-2641
Subject:
levulinic acid,   etc   ; biomass; catalysts; catalytic activity; comparative study; hydrogenation; lactones; microwave radiation; models; ovens; ruthenium; temperature;     Show all 12 Subjects
Abstract:
... Conversion of biomass-derived levulinic acid to γ-valerolactone (GVL) via catalytic transfer hydrogenation (CTH) using conventional oven heating (COH) is associated with issues, such as long reaction time, and low yield. Microwave irradiation (MWI) appears to be a solution to address these issues as MWI can shorten reaction times and enhance yields. To explore effectiveness of MWI for LA conversio ...
DOI:
10.1007/s12649-019-00623-y

12. Effects of water in the heterogeneous catalytic valorization of levulinic acid into γ-valerolactone and its derivatives

Author:
Weng, Rengui; Yu, Zhihao; Xiong, Jian; Lu, Xuebin
Source:
Green chemistry 2020 v.22 no.10 pp. 3013-3027
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; biofuels; biomass; biorefining; catalytic activity; cellulose; green chemistry; lactones; solvents; value added;     Show all 10 Subjects
Abstract:
... Levulinic acid (LA), which is considered a versatile biomass-derived molecular platform, typically occupies a core position in the cellulosic biorefinery system. The heterogeneous catalytic valorization of LA for the synthesis of various value-added chemicals and biofuels has been extensively investigated over the past decade, in which the solvent strategy has been reported to exert a significant ...
DOI:
10.1039/d0gc01082k

13. One-pot selective production of levulinic acid and formic acid from spent coffee grounds in a catalyst-free biphasic system

Author:
Kim, Bora; Yang, Jeongwoo; Kim, Minji; Lee, Jae W.
Source:
Bioresource technology 2020 v.303 pp. 122898
ISSN:
0960-8524
Subject:
levulinic acid,   etc   ; ethylene dichloride; formic acid; humin; hydrogen; lipids; monosaccharides; spent coffee grounds; temperature;     Show all 9 Subjects
Abstract:
... This study introduces the catalyst-free production of levulinic acid (LA) and formic acid (FA) from spent coffee grounds (SCGs) as a starting material in a biphasic system of 1,2-dichloroethane (DCE)-water at temperatures above 160 °C. In addition to the advantage of using the biphasic system attributed to the product equilibrium, DCE served as a source of hydrogen induced by subcritical water (SC ...
DOI:
10.1016/j.biortech.2020.122898

14. Efficient catalytic production of biomass-derived levulinic acid over phosphotungstic acid in deep eutectic solvent

Author:
Li, Xiaoyun; Lu, Xuebin; Nie, Shuangxi; Liang, Min; Yu, Zhihao; Duan, Bingyu; Yang, Jiaxin; Xu, Rui; Lu, Lefu; Si, Chuanling
Source:
Industrial crops and products 2020 v.145 pp. 112154
ISSN:
0926-6690
Subject:
levulinic acid,   etc   ; activation energy; biorefining; catalysts; catalytic activity; cellulose; glucose; kinetics; phosphotungstic acid; solvents; temperature;     Show all 11 Subjects
Abstract:
... A feasible approach to convert glucose and cellulose to levulinic acid applying phosphotungstic acid as catalyst in deep eutectic solvent was proposed. In our study, phosphotungstic acid was considered to be an effective catalyst for levulinic acid production. A considerable yield of levulinic acid (98.9 %) from glucose was achieved using 30 g/L phosphotungstic acid as catalyst at 468 K for 80 min ...
DOI:
10.1016/j.indcrop.2020.112154

15. A review about GVL production from lignocellulose: Focusing on the full components utilization

Author:
Ye, Lei; Han, Yiwen; Feng, Jing; Lu, Xuebin
Source:
Industrial crops and products 2020 v.144 pp. 112031
ISSN:
0926-6690
Subject:
levulinic acid,   etc   ; biomass; catalytic activity; cellulose; furfural; hemicellulose; hydrogenation; hydrolysis; lactones; lignin; lignocellulose; reaction mechanisms; sugars;     Show all 13 Subjects
Abstract:
... γ-Valerolactone (GVL) is considered to be one of the most promising biomass platform compounds, and it can be synthesized using different reaction pathways from cellulose and hemicellulose, as well as their degradation derivatives. Based on the production of GVL and a preference for using whole biomass components, this paper comprehensively summarizes the catalytic system and reaction mechanism of ...
DOI:
10.1016/j.indcrop.2019.112031

16. Preparation of Polar-Modified Styrene-Divinylbenzene Copolymer and Its Adsorption Performance for Comprehensive Utilization of Sugarcane Bagasse Dilute-Acid Hydrolysate

Author:
Zhang, Liquan; Chen, Xuefang; Zhang, Hairong; Guo, Haijun; Wang, Can; Wang, Mengkun; Yao, Shimiao; Lin, Xiaoqing; Chen, Xinde
Source:
Applied biochemistry and biotechnology 2020 v.190 no.2 pp. 423-436
ISSN:
0273-2289
Subject:
levulinic acid,   etc   ; adsorbents; adsorption; composite polymers; desorption; furfural; hydrolysates; hydrolysis; lignocellulose; resins; sugarcane bagasse; sugars;     Show all 12 Subjects
Abstract:
... Lignocellulosic hydrolysate contains complex nonsugar compounds and undegraded sugars in the process of preparing platform compound levulinic acid (LA) and furfural by one-step dilute-acid hydrolysis. For efficiently and comprehensively utilizing the hydrolysate, a series of polar modified resins were synthesized for adsorption and separation of the sugarcane bagasse hydrolysate to obtain platform ...
DOI:
10.1007/s12010-019-03100-3

17. Synergistic Effects of Furfural and Sulfuric Acid on the Decomposition of Levulinic Acid

Author:
Chen, Wenbing; Hu, Hanwen; Cai, Qinjie; Zhang, Suping
Source:
Energy & fuels 2020 v.34 no.2 pp. 2238-2245
ISSN:
1520-5029
Subject:
levulinic acid,   etc   ; activation energy; biomass; catalysts; furfural; hemicellulose; hydrolysis; kinetics; sulfuric acid; synergism;     Show all 10 Subjects
Abstract:
... The decomposition of levulinic acid (LA) is a critical factor limiting the yield of LA produced by biomass hydrolysis. In this study, the effects of influencing factors, especially furfural, on the decomposition of LA were investigated. Results show that furfural, as a hemicellulose hydrolysis product, led to an increase in LA decomposition; 25.3% of LA decomposed when furfural concentration was 0 ...
DOI:
10.1021/acs.energyfuels.9b03971

18. A review on catalytic synthesis of energy rich fuel additive levulinate compounds from biomass derived levulinic acid

Author:
Badgujar, Kirtikumar C.; Badgujar, Vivek C.; Bhanage, Bhalchandra M.
Source:
Fuel processing technology 2020 v.197 pp. 106213
ISSN:
0378-3820
Subject:
levulinic acid,   etc   ; biomass; catalysts; catalytic activity; energy; esters; fuels; markets; mixing; value added;     Show all 10 Subjects
Abstract:
... Levulinate esters are unique potential value added energy-chemicals which has significantly attracted remarkable attention of global researchers due to its potential importance as a fuel-blending chemical. Conversely, competent synthesis of levulinate compounds is in initial phase of research which mostly involves the challenging catalytic synthesis. The existing literature showed that, the role o ...
DOI:
10.1016/j.fuproc.2019.106213

19. Lignin-based solid acid catalyst for the conversion of cellulose to levulinic acid using γ-valerolactone as solvent

Author:
Han, Yiwen; Ye, Lei; Gu, Xiaochao; Zhu, Puli; Lu, Xuebin
Source:
Industrial crops and products 2019 v.127 pp. 88-93
ISSN:
0926-6690
Subject:
levulinic acid,   etc   ; catalysts; cellulose; lignin; solubility; solvents;     Show all 6 Subjects
Abstract:
... Lignin was used as a carrier and loaded with ferrous sulfide to prepare a new type of solid acid catalyst for the catalytic conversion of cellulose to levulinic acid using γ-valerolactone as the solvent. The solubility characteristic of cellulose in γ-valerolactone was studied which proved that cellulose is physically soluble in γ-valerolactone. The performance of the new solid acid catalyst was e ...
DOI:
10.1016/j.indcrop.2018.10.058

20. Metabolic engineering of Pseudomonas putida for the production of various types of short-chain-length polyhydroxyalkanoates from levulinic acid

Author:
Cha, Daegeun; Ha, Hyo Seok; Lee, Sung Kuk
Source:
Bioresource technology 2020 v.309 pp. 123332
ISSN:
0960-8524
Subject:
levulinic acid,   etc   ; Pseudomonas putida; acetyl coenzyme A; acetyl-CoA acetyltransferase; biochemical pathways; metabolic engineering; plastics; poly-3-hydroxybutyrate;     Show all 8 Subjects
Abstract:
... Poly(3-hydroxybutyrate), a short-chain-length polyhydroxyalkanoate (scl-PHA), is considered as a good alternative to conventional synthetic plastics. However, various biopolymers with diverse characteristics are still in demand. In this study, four different types of scl-PHA were successfully produced by engineering levulinic acid (LA) utilization metabolic pathway and expressing heterologous PHA ...
DOI:
10.1016/j.biortech.2020.123332