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1. 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

2. Dual acidic mesoporous KIT silicates enable one-pot production of γ-valerolactone from biomass derivatives via cascade reactions

Author:
He, Jian; Li, Hu; Xu, Yufei; Yang, Song
Source:
Renewable energy 2020 v.146 pp. 359-370
ISSN:
0960-1481
Subject:
levulinic acid,   etc   ; Bronsted acids; active sites; biofuels; biomass; carbonyl compounds; catalysts; catalytic activity; esters; furfural; hydrogenation; isopropyl alcohol; porous media; silica; silicates; silicon; solvents; zirconium;     Show all 18 Subjects
Abstract:
... γ-Valerolactone (GVL) is an interesting bio-based platform molecule that is utilized as green solvent and a versatile building block for the synthesis of bio-fuels and chemicals. Herein, an investigation on the efficient production of GVL from biomass-based carbonyl compounds such as furfural, levulinic acid, and its esters using 2-propanol as H-donor and solvent over stable Zr-incorporated mesopo ...
DOI:
10.1016/j.renene.2019.06.105

3. Kinetic and thermodynamic studies of oil palm mesocarp fiber cellulose conversion to levulinic acid and upgrading to ethyl levulinate via indium trichloride-ionic liquids

Author:
Tiong, Yong Wei; Yap, Chiew Lin; Gan, Suyin; Yap, Winnie Soo Ping
Source:
Renewable energy 2020 v.146 pp. 932-943
ISSN:
0960-1481
Subject:
levulinic acid,   etc   ; Elaeis guineensis; Gibbs free energy; activation energy; catalysts; catalytic activity; cellulose; depolymerization; energy; esterification; hydrogen; indium; ionic liquids; kinetics; mesocarp; renewable energy sources; sulfates; temperature;     Show all 18 Subjects
Abstract:
... This study investigated the kinetic and thermodynamic studies of oil palm mesocarp fiber cellulose conversion to levulinic acid and upgrading to ethyl levulinate via an eco-friendly Bronsted-Lewis acidic ionic liquid, that is, indium trichloride-1-methylimidazolium hydrogen sulfate (InCl3-[HMIM][HSO4]). The conversion reactions, i.e. cellulose depolymerisation to levulinic acid, and the subsequent ...
DOI:
10.1016/j.renene.2019.07.024

4. Renewable polymers: Synthesis and characterization of poly(levulinic acid–pentaerythritol) Part A Polymer chemistry

Author:
Amarasekara, Ananda S.; Ha, Uyen; Okorie, Nnaemeka C.
Source:
Journal of polymer science 2018 v.56 no.9 pp. 955-958
ISSN:
0887-624X
Subject:
levulinic acid,   etc   ; carbon; catalysts; heat; thermoplastics;     Show all 5 Subjects
Abstract:
... The heating of a levulinic acid and pentaerythritol 4:3 mixture with Sb₂O₃ catalyst at 23–210 °C gives poly(levulinic acid–pentaerythritol). This all renewable carbon based moldable white thermoplastic is shown to contain a structure with ester and ketal links. ...
DOI:
10.1002/pola.28980

5. Metal-organic framework containing Brønsted acidity and Lewis acidity for efficient conversion glucose to levulinic acid

Author:
Qu, Haonan; Liu, Bingyi; Gao, Guohua; Ma, Yiming; Zhou, Yanmei; Zhou, Hua; Li, Li; Li, Yonghong; Liu, Shengjian
Source:
Fuel processing technology 2019 v.193 pp. 1-6
ISSN:
0378-3820
Subject:
levulinic acid,   etc   ; acidity; biomass; catalysts; coordination compounds; glucose; iron; lysine; phosphotungstic acid;     Show all 9 Subjects
Abstract:
... Levulinic acid (LA) is a versatile key building block in the conversion of carbohydrates and it is an important basic chemical with various potential uses. MIL-100(Fe) loading with insoluble lysine functionalized phosphotungstic acid (Lys-PM2) as heterogeneous catalysts have been synthesized for the conversion of glucose to LA in water. The optimized yield of LA is obtained by using Lys-PM2 to cat ...
DOI:
10.1016/j.fuproc.2019.04.035

6. Water-born zirconium-based metal organic frameworks as green and effective catalysts for catalytic transfer hydrogenation of levulinic acid to γ-valerolactone: Critical roles of modulators

Author:
Yun, Wan-Chu; Yang, Ming-Tong; Lin, Kun-Yi Andrew
Source:
Journal of colloid and interface science 2019 v.543 pp. 52-63
ISSN:
0021-9797
Subject:
levulinic acid,   etc   ; catalysts; catalytic activity; crystal structure; dimethylformamide; formic acid; hydrogenation; propionic acid; solvents; toxicity; zirconium;     Show all 11 Subjects
Abstract:
... While zirconium (Zr)-based metal organic frameworks (MOFs) are promising for conversion of levulinic acid (LA) to γ-valerolactone (GVL) through catalytic transform hydrogenation (CTH), these reported Zr MOFs for LA conversion must be synthesized in toxic dimethylformamide (DMF). From the viewpoint of sustainability, it is preferable to avoid usage of DMF-based solvents to prepare these Zr MOFs. As ...
DOI:
10.1016/j.jcis.2019.02.036

7. Reactions of levulinic acid and pseudolevulinic esters with various C-nucleophiles

Author:
Shcherbinin, Vitaly A.; Spesivaya, Ekaterina S.; Konshin, Valery V.
Source:
Tetrahedron letters 2019 v.60 no.14 pp. 957-960
ISSN:
0040-4039
Subject:
levulinic acid,   etc   ; Lewis bases; acetates; chemical structure; cyclization reactions; raw materials;     Show all 6 Subjects
Abstract:
... The reactions of levulinic acid and its pseudo esters, which are readily available from carbohydrate-containing raw materials, with various C-nucleophiles are described. Different reaction pathways were demonstrated depending on the nature of the leaving groups and nucleophiles. For 5-methyl-5-methoxydihydrofuran-2(3H)-one, the reaction was found to proceed by a route giving hept-6-enoic acid deri ...
DOI:
10.1016/j.tetlet.2019.02.046

8. Efficient and sustainable hydrogenation of levulinic-acid to gamma-valerolactone in aqueous solution over acid-resistant CePO₄/Co₂P catalysts

Author:
Feng, Hui-Juan; Li, Xiao-Chen; Qian, Hao; Zhang, Ya-Fang; Zhang, Di-Hui; Zhao, Dan; Hong, San-Guo; Zhang, Ning
Source:
Green chemistry 2019 v.21 no.7 pp. 1743-1756
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; acid tolerance; aqueous solutions; biomass; catalysts; catalytic activity; green chemistry; hydrogen; hydrogenation; lignocellulose;     Show all 10 Subjects
Abstract:
... Developing a highly active, acid-resistant and low-cost catalyst which can perform well in aqueous solution has long been sought for practical and sustainable lignocellulosic biomass transformation. In this work, a series of Ce–P–Co heterogeneous catalysts were prepared by a convenient solvothermal method for catalytic hydrogenation of levulinic acid (LA) to gamma-valerolactone (GVL) in water. By ...
DOI:
10.1039/c9gc00482c

9. Production of 5-hydroxymethylfurfural and levulinic acid from lignocellulosic biomass and catalytic upgradation

Author:
Li, Xiaoyun; Xu, Rui; Yang, Jiaxin; Nie, Shuangxi; Liu, Dan; Liu, Ying; Si, Chuanling
Source:
Industrial crops and products 2019 v.130 pp. 184-197
ISSN:
0926-6690
Subject:
levulinic acid,   etc   ; aqueous solutions; biomass; carbon; catalysts; fossils; fuels; hydroxymethylfurfural; lignocellulose; solvents;     Show all 10 Subjects
Abstract:
... 5-Hydroxymethylfurfural (HMF) and levulinic acid (LA), produced from lignocellulosic biomass, can be catalytically upgraded to valuable chemicals and fuels. Lignocellulosic biomass has been considered as an alternative carbon resource for fossil. This work reviews the recent development of HMF and LA production from lignocellulosic biomass, which focuses on pretreatment of lignocellulosic biomass, ...
DOI:
10.1016/j.indcrop.2018.12.082

10. Simultaneous production of furfural and levulinic acid from pine sawdust via acid-catalysed mechanical depolymerization and microwave irradiation

Author:
Lappalainen, Katja; Dong, Yue
Source:
Biomass and bioenergy 2019 v.123 pp. 159-165
ISSN:
0961-9534
Subject:
levulinic acid,   etc   ; aluminum chloride; catalysts; depolymerization; furfural; microwave radiation; microwave treatment; milling; sawdust;     Show all 9 Subjects
Abstract:
... In this work pine sawdust was converted into levulinic acid (LA) and furfural. Sawdust was first pre-treated with sulfuric acid-catalysed mechanical depolymerization. The conversion reactions were then performed with microwave heating at 180 °C. To enhance the furfural yield and the efficient separation of furfural and LA, a biphasic water-toluene reaction system was used. The effect of an additio ...
DOI:
10.1016/j.biombioe.2019.02.017

11. Conversion of levulinic acid to γ-valerolactone over ultra-thin TiO₂ nanosheets decorated with ultrasmall Ru nanoparticle catalysts under mild conditions

Author:
Li, Shaopeng; Wang, Yanyan; Yang, Youdi; Chen, Bingfeng; Tai, Jing; Liu, Huizhen; Han, Buxing
Source:
Green chemistry 2019 v.21 no.4 pp. 770-774
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; ambient temperature; catalysts; catalytic activity; energy; green chemistry; nanoparticles; nanosheets; titanium dioxide;     Show all 9 Subjects
Abstract:
... Herein, we demonstrate that quantum-sized Ru dot decorated ultra-thin anatase TiO₂ nanosheets with exposed (001) facets could exhibit highly efficient catalytic activity during the conversion of levulinic acid to γ-valerolactone at room temperature. The support effect has been largely attributed to the high energy of TiO₂ (001) which can lead to a stronger interaction between the support and the m ...
DOI:
10.1039/c8gc03529f

12. Engineering the lva operon and Optimization of Culture Conditions for Enhanced Production of 4-Hydroxyvalerate from Levulinic Acid in Pseudomonas putida KT2440

Author:
Sathesh-Prabu, Chandran; Lee, Sung Kuk
Source:
Journal of agricultural and food chemistry 2019 v.67 no.9 pp. 2540-2546
ISSN:
1520-5118
Subject:
levulinic acid,   etc   ; Escherichia coli; Pseudomonas putida; biomass; cost effectiveness; engineering; gene overexpression; operon; products and commodities;     Show all 9 Subjects
Abstract:
... Monomeric 4-hydroxyvalerate is a versatile chemical used to produce various commodities and fine chemicals. In the present study, the lvaAB gene was deleted from the lva operon in Pseudomonas putida KT2440 and tesB, obtained from Escherichia coli, was overexpressed under the control of the lva operon system, which is induced by the substrate levulinic acid and the product 4-hydroxyvalerate to prod ...
DOI:
10.1021/acs.jafc.8b06884

13. Ambient Reductive Amination of Levulinic Acid to Pyrrolidones over Pt Nanocatalysts on Porous TiO₂ Nanosheets

Author:
Xie, Chao; Song, Jinliang; Wu, Haoran; Hu, Yue; Liu, Huizhen; Zhang, Zhanrong; Zhang, Pei; Chen, Bingfeng; Han, Buxing
Source:
Journal of the American Chemical Society 2019 v.141 no.9 pp. 4002-4009
ISSN:
1520-5126
Subject:
levulinic acid,   etc   ; acidity; ambient temperature; amination; biomass; catalysts; esters; hydrogen; nanoparticles; nanosheets; pyrrolidones; titanium dioxide;     Show all 12 Subjects
Abstract:
... Construction of N-substituted pyrrolidones from biomass-derived levulinic acid (LA) via reductive amination is a highly attractive route for biomass valorization. However, realizing this transformation using H₂ as the hydrogen source under mild conditions is still very challenging. Herein, we designed porous TiO₂ nanosheets-supported Pt nanoparticles (Pt/P-TiO₂) as the heterogeneous catalyst. The ...
DOI:
10.1021/jacs.8b13024

14. Highly Efficient Synthesis of Alkyl Levulinates from α-Angelica Lactone, Catalyzed with Lewis Acidic Trifloaluminate Ionic Liquids Supported on Carbon Nanotubes

Author:
Latos, Piotr; Szelwicka, Anna; Boncel, Sławomir; Jurczyk, Sebastian; Swadźba-Kwaśny, Małgorzata; Chrobok, Anna
Source:
ACS sustainable chemistry & engineering 2019 v.7 no.5 pp. 5184-5191
ISSN:
2168-0485
Subject:
levulinic acid,   etc   ; aluminum; anions; byproducts; carbon nanotubes; catalysts; esters; hydrolysis; ionic liquids; leaching;     Show all 10 Subjects
Abstract:
... Levulinic acid esters (LAEs) were synthesized from α-angelica lactone and alcohols, in a reaction catalyzed by a new family of chloride-free Lewis acidic ionic liquids, containing trifloaluminate anions, [Al(OTf)₃₊ₙ]ⁿ⁻. Changing the catalyst from poorly soluble Al(OTf)₃ (used as suspension) to fully homogeneous trifloaluminate ionic liquids resulted in shorter reaction times required for full α-AL ...
DOI:
10.1021/acssuschemeng.8b06066

15. Enhanced Levulinic Acid Production from Cellulose by Combined Brønsted Hydrothermal Carbon and Lewis Acid Catalysts

Author:
Boonyakarn, Tat; Wataniyakul, Piyaporn; Boonnoun, Panatpong; Quitain, Armando T.; Kida, Tetsuya; Sasaki, Mitsuru; Laosiripojana, Navadol; Jongsomjit, Bunjerd; Shotipruk, Artiwan
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.8 pp. 2697-2703
ISSN:
1520-5045
Subject:
levulinic acid,   etc   ; Lewis acids; biomass; carbon; catalysts; cellulose; chlorides; chromium; ecosystem services; process design; temperature;     Show all 11 Subjects
Abstract:
... This study presents a synergistic catalytic system using the combination of Brønsted hydrothermal carbon-based acid (HTCG-SO₃H) and Lewis acid catalysts for one-pot conversion of cellulose to levulinic acid (LA). Chromium chloride (CrCl₃), among a number of other Lewis acidic metal chlorides, was found to give the highest LA yields, and was therefore used in combination with the HTCG-SO₃H, for cel ...
DOI:
10.1021/acs.iecr.8b05332

16. Effect of lignocellulose-derived weak acids on butanol production by Clostridium acetobutylicum under different pH adjustment conditions

Author:
Wang, Jianhui; Yang, Hongyan; Qi, Gaoxaing; Liu, Xuecheng; Gao, Xu; Shen, Yu
Source:
RSC advances 2019 v.9 no.4 pp. 1967-1975
ISSN:
2046-2069
Subject:
levulinic acid,   etc   ; Clostridium acetobutylicum; butanol; calcium carbonate; fermentation; formic acid; hydrolysates; lignocellulose; pH; potassium hydroxide;     Show all 10 Subjects
Abstract:
... The effects of formic acid, acetic acid and levulinic acid on acetone–butanol–ethanol (ABE) fermentation under different pH adjustment conditions were investigated using Clostridium acetobutylicum as the fermentation strain. CaCO₃ supplementation can alleviate the inhibitory effect of formic acid on ABE production. The ABE titers from the medium containing 0.5 g L⁻¹ formic acid with pH adjusted by ...
DOI:
10.1039/c8ra08678h

17. Fabrication of 2D metal–organic framework nanosheets with tailorable thickness using bio-based surfactants and their application in catalysis

Author:
Zhang, Xiudong; Zhang, Pei; Chen, Chunjun; Zhang, Jianling; Yang, Guanying; Zheng, Lirong; Zhang, Jing; Han, Buxing
Source:
Green chemistry 2019 v.21 no.1 pp. 54-58
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; catalytic activity; coordination polymers; green chemistry; hydrogenation; hydrophobicity; nanoparticles; nanosheets; surfactants;     Show all 9 Subjects
Abstract:
... Ultrathin metal–organic framework (MOF) nanosheets were fabricated by a surfactant-mediated coordination strategy through a pseudo-assembly process. The thickness of the nanosheets could be tuned from 3 nm to 60 nm by varying the hydrophobic chain length of the surfactant. Ru nanoparticles supported on the nanosheets exhibited superior catalytic activity for hydrogenation of levulinic acid to γ-va ...
DOI:
10.1039/c8gc02835d

18. The Use of Azohydromonas lata DSM 1122 to Produce 4-hydroxyvalerate-Containing Polyhydroxyalkanoate Terpolymers, and Unique Polymer Blends from Mixed-Cultures with Burkholderia sacchari DSM 17165

Author:
Ashby, Richard D.; Solaiman, Daniel K. Y.; Strahan, Gary D.
Source:
Journal of polymers and the environment 2019 v.27 no.1 pp. 198-209
ISSN:
1566-2543
Subject:
levulinic acid,   etc   ; Azohydromonas; Burkholderia sacchari; cell growth; glucose; mixed culture; molecular weight; polyhydroxyalkanoates; tensile strength;     Show all 9 Subjects
Abstract:
... Azohydromonas lata DSM 1122 was utilized to synthesize short-chain-length (scl-) polyhydroxyalkanoate (PHA) terpolymers containing 3-hydroxybutyric (3HB) acid, 3-hydroxyvaleric (3HV) acid, and 4-hydroxyvaleric (4HV) acid from mixtures of glucose (GLC; 1 wt%) and levulinic acid (LevA; 0–0.4 wt%). LevA media concentrations greater than 0.4% completely inhibited cellular growth. At LevA concentration ...
DOI:
10.1007/s10924-018-1332-2

19. Solid acid-induced hydrothermal treatment of bagasse for production of furfural and levulinic acid by a two-step process

Author:
Wang, Xiaohui; Zhang, Chunhui; Lin, Qixuan; Cheng, Banggui; Kong, Fangong; Li, Huiling; Ren, Junli
Source:
Industrial crops and products 2018 v.123 pp. 118-127
ISSN:
0926-6690
Subject:
levulinic acid,   etc   ; bagasse; catalysts; cellulose; furfural; hemicellulose; hot water treatment;     Show all 7 Subjects
Abstract:
... A two-step process was developed to produce furfural and levulinic acid (LA) using the solid acid-induced hydrothermal treatment of bagasse. In the first step, hydrothermal pretreatment was applied to treat bagasse for producing furfural using Sn-MMT/SO42− solid acids as catalysts in the biphasic system. In the second step, the treated residue was further hydrothermally treated for producing LA by ...
DOI:
10.1016/j.indcrop.2018.06.064

20. Valorization of levulinic acid over non-noble metal catalysts: challenges and opportunities

Author:
Xue, Zhimin; Liu, Qiaoling; Wang, Jinfang; Mu, Tiancheng
Source:
Green chemistry 2018 v.20 no.19 pp. 4391-4408
ISSN:
1463-9270
Subject:
levulinic acid,   etc   ; biomass; catalysts; catalytic activity; cellulose; green chemistry; metals;     Show all 7 Subjects
Abstract:
... Levulinic acid (LA), easily derived from cellulose via an acid catalytic process, is an attractive biomass-derived platform chemical which can be converted into various valuable chemicals, and LA valorization is an important component in biomass transformation. For LA conversion, non-noble metal catalytic systems have attracted significant attention due to their low cost compared with noble metals ...
DOI:
10.1039/c8gc02001a