RSC Advances
·
2021
·Vol. 12
·期 1
·602-610
·
IF 3.361
Yingxin Liu,Kai Liu,Meihua Zhang,Kaiyue Zhang,Jiao Ma,Shuwen Xiao,Zuojun Wei,Shuguang Deng
Highly active and thermally stable Cu–Re bimetallic catalysts supported on TiO2 with 2.0 wt% loading of Cu were prepared via an incipient wetness impregnation method and were applied for liquid phase selective hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) in H2. The effect of the molar ratios of Cu : Re on the physico-chemical properties and the catalytic performance of the Cu–Re/TiO2 catalysts was investigated. Moreover, the influence of various reaction parameters on the hydrogenation of LA to GVL was studied. The results showed that the Cu–Re/TiO2 catalyst with a 1 : 1 molar ratio of Cu to Re (Cu–Re(1 : 1)/TiO2) exhibited the highest performance for the reaction. Complete conversion of LA with a 100% yield of GVL was achieved in 1,4-dioxane solvent under the reaction conditions of 180 °C, 4.0 MPa H2 for 4 h, and the catalyst could be reused at least 6 times with only a slight loss of activity. Combined with the characterization results, the high performance of the catalyst was mainly attributed to the well-dispersed Cu–Re nanoparticles with a very fine average size (ca. 0.69 nm) and the co-presence of Cu–Re bimetal and ReOx on the catalyst surface.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MATERIALS RESEARCH BULLETIN
·
2020
·
IF 4.019
Jingru Wang,Shanhui Zhu,Yunwei Wang,Yingyong Wang,Guoqiang Jin,Xili Tong,Xiangyun Guo
The hydrogenation of levulinic acid (LA) to γ-valerolactone (GVL) under mild condition is a promising but challenging process. Herein, SiC supported Ru-Ir bimetallic catalyst exhibit enhanced catalytic activity for aqueous hydrogenation of LA into GVL under mild conditions. Comparing with monometallic Ir 3 /SiC and Ru 3 /SiC, the conversion of LA over bimetallic Ru 0.5 -Ir 2.5 /SiC catalyst increase from 51.2 % and 45.9% to 100% at 25 °C and 0.2 MPa of H 2 pressure. The enhanced catalytic activity of Ru 0.5 -Ir 2.5 /SiC catalyst originates from the electronic synergistic effect among Ru, Ir and SiC. Due to the electron transfer, electron-richened Ir nanoparticles show stronger ability for H 2 dissociation, and the SiC surface produces more active sites to accommodate hydrogen species that spill over from Ir and Ru. The adsorption and hydrogenation of LA molecules occur on the surface of SiC.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2019
·Vol. 150
·期 2
·322-331
·
IF 2.372
Wang Kaifeng,Liu Ya,Wu Wufeng,Chen Yu,Fang Lina,Li Wanbin,Ji Hongbing
Abstract In this study, Zr-MOF material (UiO-66) was modified with different metal oxides (CeO 2 , Ga 2 O 3 , and CoO) and employed in the conversion of cellulose to levulinic acid (LA) in aqueous medium. The research results showed that the introduction of the metal oxides increased the acid content of the catalysts, especially in medium-strong acid. The selectivity of LA was related to the type of metal oxide and the content of medium-strong acid. Due to the activity of Ga 2 O 3 and more medium-strong acid, the yield of LA reaches a maximum yield of 32.0 mol% at 513 K for 360 min when Ga 2 O 3 -UiO-66 was employed as the catalysts. The combination of metal oxide and UiO-66 enables the reaction to proceed, providing a new direction for the conversion of cellulose to LA in the aqueous phase. Graphic Abstract In this study, Zr-MOFs material (UiO-66) was modified with different metal oxides (CeO 2 , Ga 2 O 3 , and CoO) and employed in the conversion of cellulose to levulinic acid in aqueous medium. The results indicated that the addition of metal oxides changes the acidity of UiO-66, which improves the catalytic activity. The selectivity of LA was related to the type of metal oxide and the content of medium-strong acid.
✓ 已验证
产品关联
DOI
高影响因子
GREEN CHEMISTRY
·
2019
·Vol. 21
·期 3
·606-613
·
IF 9.405
Zhenbing Xie,Bingfeng Chen,Haoran Wu,Mingyang Liu,Huizhen Liu,Jianling Zhang,Guanying Yang,Buxing Han
Transformation of biomass or biomass-based feedstocks into fuels or valuable chemicals is of great importance for the sustainable development of our society. Mesoporous Al2O3–ZrO2 with different Al : Zr molar ratios was prepared by the sol–gel method, and Cu–Ni/Al2O3–ZrO2 catalysts were fabricated by the impregnation method. The catalytic performances of the bifunctional catalysts were studied in the selective hydrogenation of levulinic acid (LA) into 2-methyltetrahydrofuran (MTHF). It was demonstrated that both Cu : Ni and Al : Zr ratios affected the selectivity to MTHF significantly. The bimetallic catalysts Cu–Ni/Al2O3–ZrO2 containing 10 wt% Ni and 10 wt% Cu gave 99.8% MTHF selectivity at full conversion of LA when the Al : Zr ratio was 9 : 1. The outstanding catalytic performance of the catalyst is related to the mesoporous structure, the acidic properties of the support and the synergistic effect between Cu and Ni. The catalyst could be reused five times without a considerable loss of catalytic activity and selectivity.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2016
·
IF 4.312
Kun Jiang,Dong Sheng,Zihao Zhang,Jie Fu,Zhaoyin Hou,Xiuyang Lu
Mixed MgO–Al 2 O 3 (with different Mg/Al ratio) supported nickel catalysts were prepared via co-precipitation method and used for hydrogenation of levulinic acid to γ-valerolactone under mild condition. Characterization results indicated that mixed MgO–Al 2 O 3 supported Ni catalysts possessed bigger surface area than that of Ni/MgO and Ni/Al 2 O 3 , and Ni dispersed highly on the surface of mixed MgO–Al 2 O 3 support. It was found that mixed MgO–Al 2 O 3 supported Ni catalysts were more active and selective for the hydrogenation of levulinic acid to γ-valerolactone than that of Ni/MgO and Ni/Al 2 O 3 , and the best yield of γ-valerolactone at 160 °C, 1 h and 3 MPa H 2 reached 99.7% over Ni/MgAlO 2.5 , and Ni/Mg 2 Al 2 O 5 could be recycled without obvious loss of its initial activity.
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS TODAY
·
2017
·
IF 4.636
Zhijie Wu,Min Zhang,Yirong Yao,Jingtuo Wang,Danhong Wang,Minghui Zhang,Yongfeng Li
1,3-propanediol (1,3-PDO) and γ-valerolactone (GVL) were simultaneously obtained via the hydrogenolysis of glycerol in levulinic acid (LA) using Ru/C catalysts. Ru/C catalyst exhibited a high LA conversion (∼99%) and a high GVL selectivity (∼99%) for the hydrogenation of LA; while a low conversion (∼11%) and little selectivity of 1,3-PDO for the hydrogenolysis of glycerol. LA promoted the hydrogenolysis of glycerol over Ru/C catalyst, in which LA catalyzed dehydration of glycerol into acetol (precursor of 1,2-propanediol (1,2-PDO)), and glycerol acetalization with the hydrogenated GVL into cyclic acetals, resulting in the formation of 1,3-PDO. A reaction scheme involves the formation of cyclic acetal ethers between GVL and glycerol was proposed to explain the product distributions in the one-pot synthesis of 1,3-PDO and GVL. 64.5% conversion of glycerol and 35.8% selectivity of 1,3-PDO together with 99.1% conversion of LA and 85.8% selectivity of GVL were obtained during one-pot converting glycerol and LA with 3.0 MPa H 2 at 200 °C for 6 h. We reported an effective strategy for the preparation of 1,3-PDO by selective hydrogenolysis of dioxan originated from glycerol with aldehydes or ketones.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2016
·
IF 5.267
Ye-Zhi Qin,Min-Hua Zong,Wen-Yong Lou,Ning Li
Valorization of biomass-based platform chemicals into high value-added products has attracted increasing attention recently. In this work, upgrading of 5-hydroxymethylfurfual (HMF) and levulinic acid, two important biomass-based platform chemicals, to HMF levulinate via a green and efficient enzymatic approach was reported. Novozym 435 was found to be the best biocatalyst for the enzymatic esterification. The enzymatic esterification progressed smoothly in t-butanol, 2-methyl-2-butanol, and cyclopentyl methyl ether as well as in the ecofriendly biomass-derived 2-methyltetrahydrofuran (2-MeTHF), while no enzymatic reaction occurred in deep eutectic solvents. When HMF concentration was up to 500 mM, a good conversion of 72% was achieved in 2-MeTHF. The reaction temperature exerted a significant effect on the enzymatic esterification. When the reaction temperature is below 40 °C, high HMF conversions (>85%) were obtained. Besides, significant inactivation of the enzyme was observed at more than 50 °C, resulting in poor conversions.
✓ 已验证
产品关联
DOI
高影响因子
ChemSusChem
·
2017
·Vol. 10
·期 8
·1720-1732
·
IF 7.226
Zuojun Wei,Jiongtao Lou,Chuanmin Su,Dechao Guo,Yingxin Liu,Shuguang Deng
Graphical Stability through doping : The embedding of Ru nanoparticles in N-doped mesoporous carbon effectively improve the dispersion and decrease the average size of the Ru nanoparticles, improve the adsorption of levulinic acid, and increase the interaction between Ru and the support. The strategy prevents the Ru nanoparticles from migration, aggregation, and leaching, and consequently increases the reusability of the catalyst. To achieve a higher activity and reusability of a Ru-based catalyst, Ru nanoparticles were embedded in N-doped mesoporous carbon through a hard-template method. The catalyst showed excellent catalytic performance (314 h −1 turnover frequency) and recyclability (reusable five times with 3 % activity loss) for the hydrogenolysis of levulinic acid to γ-valerolactone. Compared with the mesoporous carbon without N-doping and conventional activated carbon, the introduction of N-dopant effectively improved the dispersion of Ru nanoparticles, decreased the average size of Ru nanoparticles to as small as 1.32 nm, and improved the adsorption of levulinic acid, which contributed to the increase in the activity of the catalyst. Additionally, the embedding method increased the interaction between Ru nanoparticles and carbon support in contrast with the conventional impregnation method, thus preventing the Ru nanoparticles from migration, aggregation, and leaching from the carbon surface and therefore increasing the reusability of the catalyst.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2024
·Vol. 9
·期 40
·e202403878
·
IF 1.9
Haifeng Liao,Jianwei Guo
Graphical Three kinds of heteropoly acid-based ionic liquids with different Hammett acidity were prepared for the catalytic conversion of cellulose to levulinic acid, and the effects of different solvent systems on the catalytic reactions were investigated. The results showed that higher Hammett acidity was beneficial to increase the yield of levulinic acid, and GVL/H 2 O bi-phase solvent system was helpful to extract the product to the organic phase and promote the formation of levulinic acid. Levulinic acid is an important chemical intermediate, which has many applications in organic synthesis, industry, agriculture, and medicine. In this word, three kinds of heteropoly acid based ionic liquids ([IMPS]H 2 PW 12 O 40 、[PyPS] H 2 PW 12 O 40 [TEAPS] H 2 PW 12 O 40) were used to catalyze the one-pot conversion of cellulose to levulinic acid. [IMPS]H 2 PW 12 O 40 has the highest catalytic activity due to its strong Hammett acidity ( H 0 ). In addition, the effect of biphasic solvent systems on the conversion of cellulose to levulinic acid was also studied. The results showed that the GVL/H 2 O system could effectively promote the conversion of cellulose and increase the yield of levulinic acid. The yield of levulinic acid could reach 52.6% and the conversion rate of cellulose was 91.2% at 180 °C for 180 min under the GVL/H 2 O volume ratio of 1:1 with [IMPS]H 2 PW 12 O 40 as a catalyst at 1 Mpa N 2 and cellulose as raw material. And [IMPS]H 2 PW 12 O 40 can be recycled up to five times without significant performance loss. This study provides a promising method for efficiently converting cellulose and other biomass resources to levulinic acid extraction.
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Chao Wang,Qilin Zhang,Yanglei Chen,Xueming Zhang,Feng Xu
The economically viable synthesis of levulinic acid (LA), a promising and valuable renewable biomass-derived platform for bioproducts, with high carbon efficiency is a challenge. A direct and highly effective catalytic system for conversion of xylose residues (XRs) into LA under mild conditions by using FeCl3 as catalyst and cheaply available NaCl as promoter has been developed. The NaCl solution exhibits high carbon efficiency in LA (68.0 mol %) when compared with the non-NaCl systems (48.5 mol %) due to the moderate increase of the acidity and the higher viscosity of the NaCl system than water. The experimental results demonstrated that the presence of NaCl caused no distinctive changes on reaction pathways but increased the dissolution rate and the hydrolysis rate of XRs cellulose. Moreover, further integration of our degradation process with a reactive extraction step makes energy-efficient separation of LA. The NaCl solutions easily and efficiently extracted LA into LA-derived solvent 2-methyltetrahydrofuran from aqueous solutions. The efficiency and integration of the reaction process presented a great potential for LA production from renewable biomass with the aid of concentrated seawater.
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2024
·Vol. 16
·期 3
·361
·
IF 4.7
Zeyu You,Min Yu,Renli Fu,Xiaoan Nie,Jie Chen
Herein, a bio-based plasticizer ketalized tung oil butyl levulinate (KTBL) was developed using methyl eleostearate, a derivative of tung oil, and butyl levulinate. KTBL can be used as an auxiliary plasticizer to partially replace traditional plasticizer. The plasticizer has a ketone structure, an ester base, and a long linear chain. It was mixed with dioctyl phthalate (DOP), and the effect of the plasticizer KTBL as an auxiliary plasticizer on the plasticization of poly(vinyl chloride) (PVC) was studied. Their compatibility and plasticizing effect were evaluated using dynamic–mechanical thermal analysis (DMA), mechanical property analysis, and thermogravimetric analysis (TGA). The results demonstrate that when the KTBL to DOP ratio is 1:1, the blended sample with KTBL exhibits superior mechanical performance compared to pure DOP, resulting in an increased elongation at break from 377.47% to 410.92%. Moreover, with the increase in KTBL content, the durability is also significantly improved. These findings suggest that KTBL can serve as an effective auxiliary plasticizer for PVC, thereby reducing the reliance on DOP.Keywords:renewable origin;ketal;methyl eleostearate;plasticizer;poly(vinyl chloride)
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2021
·
IF 9.381
Feng He,Jinhui Chen,Zhiwei Gong,Qinqin Xu,Wang Yue,Haibo Xie
In this study, an economically competitive and sustainable levulinic acid-based protic ionic liquids were identified to be good solvents for the dissolution pretreatment of cellulose towards enhanced enzymatic hydrolysis . The influences of protic ionic liquids species, dissolution pretreatment time, and pretreatment temperature on the physico-chemical structures of cellulose were systematically investigated by various analytical techniques. The findings indicate that the pretreatment efficiency was correlated to the basicity of the organic bases, and the presence of ketone group in the levulinate anion with particular hydrogen bonding forming ability via keto–enol tautomerism. The DBN derived protic ionic liquids exhibited best performance at 100 °C in 1 h, as evidenced by a 94% glucose yield. This solvent system was also suitable for the dissolution pretreatment of corn stover-based lignocellulosic biomass for sugars production, although a higher temperature and longer pretreatment time was required. Furthermore, the solvent system could be recycled and reused.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）