PROCESS BIOCHEMISTRY
·
2020
·
IF 2.952
Jintong Zhang,Lan Wang,Hongzhang Chen
The periodic low-frequency force can improve mixing efficiency and reduce water constraint, thus intensifying the high solids enzymatic hydrolysis . However, the availability of intensification methods for the periodic force with different frequencies needs to be studied. The periodic high-frequency vibration with rigid spheres added as another intensification method was proposed to shorten the time of water constraint and improve efficiency. Within this study, glucan and xylan conversions in periodic high-frequency vibration with rigid spheres added enzymatic hydrolysis (PVEH) increased by 8.3%-35% and 5.0%-33.5%, respectively, with solid loading increasing from 15% to 25%, compared with those in static state enzymatic hydrolysis (SEH). The physical properties variations of substrate indirectly proved the higher efficiency of PVEH. Based on the change regularity of constrained water release, PVEH was divided into three stages. The effects of micromixing and macromixing in three stages were analyzed. Additionally, the efficiency of high solids enzymatic hydrolysis can be enhanced by using proper intensification methods in different stages.
研究领域:
生物工程
·
酶学
✓ 已验证
DOI
高影响因子
FUEL
·
2022
·
IF 8.035
Yueqing Wang,Hongxing Wang,Junbo Zhang,Hongyan Zheng,Long Huang,Yulei Zhu
Selectively converting fructose into furfural by H-beta catalyst is a very interesting catalytic process. However, it is a challenging task to clearly elucidate the roles of framework Al for selective scission of C C and C O bond. Herein, selective elimination of framework Al atoms is realized. Several detailed investigations showed that the framework Al species located in different sites play important role in furfural formation. The framework Al atoms of pristine H-beta mainly occupied at T1, T2, T5, T6 and T7 sites. These Al species at pore mouth can be removed by citric acid, while the treatment of nitric acid mainly eliminated the framework Al atoms from T2 and T7 sites. As for oxalic acid, the Al atoms occupied at T2, T5, T6 and T7 was primarily leached. Upon citric acid and nitric acid treatment afforded the similar yield of furfural, indicating that the formation of furfural could not be governed by these Al species at pore mouth, T2 and T7 sites. However, in the case of oxalic acid treatment, complete removal of the Al species on T2, T5, T6 and T7 sites decreased the yield of furfural. Thus, it is reasonably inferred that these Al atoms populated at T1 sites and intersecting channels is more encouraging for the splitting of C C bond, while the Al species occupied at T5, T6 sites and the larger straight channels is probably more favorable to scission of C O bond.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Xin Yu,Lincai Peng,Jun Dai,Hui Li,Chaonan Tao,Fa Yang,Junhua Zhang
Conversion of carbohydrates at concentrated feeds represents highly desirable for the industrial deployment of biobased fuels and chemicals but challenging. One key bottleneck is that the excessive formation of polymeric humins greatly diminishes the utilization rate of feedstocks and the destination product yield. We report that the use of ethylene glycol as co-solvent for acid-catalyzed conversion of concentrated sugars enhances desirable alkyl levulinate (AL) production compared to reactions carried out in single monohydric alcohols (e.g., methanol, ethanol). Ethylene glycol served not only as a solubilizer of sugars in the reaction medium to lessen their tendency to polymerize by protecting reactive hydroxyl groups in sugars with alcohols, but also as a supporter to restrain the condensation of furan intermediates. With 10 vol% ethylene glycol as the co-solvent of ethanol, an improved yield of ethyl levulinate (EL) from 45% to 56% was accomplished from concentrated feeds of glucose (200 g/L). In particular, high space time yield and EL concentration respectively up to 30 kg/m 3 ·h and 90 g/L were obtained in a batch reactor. The solvents and catalyst could be isolated from the products, and showed good reusability. This contribution opens a reliable avenue for converting highly concentrated feeds of biomass-related sugars to oxygenated liquid fuels and versatile chemicals.
研究领域:
生物化学
·
可再生资源与环境工程
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2023
·
IF 5.5
Zhang Quanquan,Li Xin,Wang Xingwang,Huang Xin,Liu Yuncai,Wu Fengshou,Zhang Bingguang,Deng Kejian
Photocatalysis has exhibited huge potential in selective conversion of glucose into value-added chemicals. Therefore, modulation of photocatalytic material for selective upgrading of glucose is significant. Here, we have investigated the insertion of different central metal ions, Fe, Co, Mn, and Zn, into porphyrazine loading with SnO2 for access to more efficient transformation of glucose into value-added organic acids in aqueous solution at mild reaction conditions. The best selectivity for organic acids containing glucaric acid, gluconic acid, and formic acid of 85.9% at 41.2% glucose conversion was attained by using the SnO2/CoPz composite after reacting for 3 h. The effects of central metal ions on surficial potential and related possible factors have been studied. Experimental results showed that the introduction of metalloporphyrazine with different central metal ions on the surface of SnO2 has a significant effect on the separation of photogenerated charges, changing the adsorption and desorption of glucose and products on the catalyst surface. The central metal ions of cobalt and iron contributed more to the positive effects toward enhancing conversion of glucose and yields of products, and manganese and zinc contributed more to the negative effects, resulting in the poor yield of products. The differences from the central metals may attribute to the surficial potential change of the composite and the coordination effects between the metal and oxygen atom. An appropriate surficial potential environment of the photocatalyst may achieve a better interactive relationship between the catalyst and reactant, while appropriate ability of producing active species matched with adsorption and desorption abilities would gain a better yield of products. These results have provided valued ideas for designing more efficient photocatalysts in selective oxidation of glucose utilizing clean solar energy in the future.
研究领域:
化学
·
材料科学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Molecular Catalysis
·
2018
·
IF 0
Yueqing Wang,Xiaohai Yang,Hongyan Zheng,Xianqing Li,Yulei Zhu,Yongwang Li
The mechanism for the formation of furfural by dehydration of d -fructose via selective carbon-carbon (C C) bond cleavage was investigated over beta zeolite (Hβ). Several different pore size zeolites were employed to determine the shape selectivity of fructose isomers. Zeolitic pore sizes that smaller than the kinetic diameter of cyclic fructose also produced yield furfural (∼22.5%), while the high yield (66.0%) of hydroxymethylfurfural (HMF) can be achieved over large pore zeolite (USY zeolite), which could accommodate the cyclic fructose. These results indicated that the furfural formation likely began with acyclic fructose. In situ 13 C NMR and GC MS studies, using labeled 13 C-1-fructose as substrate, suggested that the conversion of fructose to furfural involved with splitting of the C5-C6 bond. Furthermore, the C1 compound from the cleavage of C C bond was identified as formaldehyde, inferring that the selective scission of C C bond was ascribe to the retro-aldol reaction. Interestingly, in situ NMR studies implied that the acyclic fructose mainly derived from pyranose forms. In addition, compared with glucose, fructose directly converted to furfural at the higher yield and reaction rate.
研究领域:
催化化学
·
有机化学
✓ 已验证
产品关联
DOI
MATERIALS CHEMISTRY AND PHYSICS
·
2022
·
IF 4.778
Xiaomei Yang,Xu Chen,Bin Lv,Yunlai Su,Lipeng Zhou
Sn-Beta zeolite is an excellent catalyst for the transformation of biomass derived carbohydrates. However, the long synthesis time restricted its application. Here, alkaline (earth) salt was used as promoter to accelerate the crystallization of Sn-Beta. Different alkaline (earth) salts and the amount of MgCl 2 were investigated. The properties of the synthesized samples were characterized by various techniques and compared with Sn-Beta, and the catalytic performance was investigated for the conversion of glucose to methyl lactate (MLA). The results indicate that a small amount of alkaline (earth) salt, especially MgCl 2 , promoted dramatically the crystallization of Sn-Beta. The full crystallization time was shortened from 15 d to 5 d with the aid of MgCl 2 ( n Mg / n Sn of 1.0) for Sn-Beta with n Si / n Sn of 100. Sn 4+ cations were incorporated into the framework sites, while Mg 2+ cations replaced the protons of silanol defects. Mg–Sn-Beta with strong Lewis acid sites and less silanols showed high activity and selectivity for glucose conversion to MLA. The yield of MLA is 20% over the fully crystallized Sn-Beta at 120 °C for 15 h and glucose concentration of 3.1 wt%, which increased significantly to 44% over the fully crystallized 1 Mg–Sn-Beta. Furthermore, Mg–Sn-Beta is stable and recyclable.
研究领域:
催化化学
·
生物质转化
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2020
·Vol. 10
·期 24
·8437-8444
·
IF 5.721
Xiaomei Yang,Liuyong Wang,Tianliang Lu,Beibei Gao,Yunlai Su,Lipeng Zhou
Hydrothermally synthesized Sn-Beta is an excellent catalyst for the conversion of sugars to alkyl lactates. However, its catalytic performance is highly dependent on the synthesis parameters. In this work, the effects of the synthesis parameters such as the water amount of the synthesis gel and the crystallization time on the synthesis and properties and catalytic performance of Sn-Beta in the conversion of glucose to methyl lactate (MLA) were investigated. The crystallization rate was accelerated remarkably by reducing the water amount of the synthesis gel. With the aid of the Si-Beta seed, Sn-Beta was almost fully-crystallized after one day with nH2O/nSiO2 of 4.5, but seven days were needed with nH2O/nSiO2 of 7.5. However, Sn-Beta synthesized with nH2O/nSiO2 of 4.5 has more extraframework SnO2 due to the fast formation of the *BEA structure and the slow incorporation of Sn4+ into the framework sites, which resulted in the lower activity of MLA formation. More Sn4+ species were incorporated into the framework sites and thus more Lewis acid sites were generated with increasing crystallization time. At the same time, the ratio of open to closed Sn sites (RO/C) increased, which led to the decrease in the activity of MLA formation and due to that, the open Sn site with a proximal silanol is unfavorable for the conversion of glucose to MLA. During recycling study, it is surprisingly found that the yield of MLA increased gradually over the fully-crystallized Sn-Beta catalyst. Characterization results of the recovered catalyst from the eighth run indicate that the structure was preserved well, but the value of RO/C reduced due to the change of the state and microenvironment of Sn species.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Fang-Yuan Bai,Jing-Ru Han,Jun Chen,Yue Yuan,Ke Wei,Yuan-Sheng Shen,Yi-Fu Huang,Heng Zhao,Jing Liu,Zhi-Yi Hu,Yu Li,Bao-Lian Su
Glucose conversion assisted photocatalytic water splitting technology to simultaneously produce H 2 and high value-added chemicals is a promising method for alleviating the energy shortage and environmental crisis. In this work, we constructing type II heterojunction by in-situ coupling Zn 0.3 Cd 0.7 S quantum dots (ZCS QDs) on three-dimensionally ordered microporous CaTiO 3 (3DOM CTO) for photocatalytic H 2 production and glucose conversion. The DFT calculations demonstrate that substitution of Zn on the Cd site improves the separation and transmission of photogenerated carriers. Therefore, 3DOM CTO-ZCS composite exhibits best H 2 production performance (2.81 mmol g -1 h −1 ) and highest apparent quantum efficiency (AQY) (5.56 %) at 365 nm, which are about 47 and 18 times that of CTO nanoparticles (NPs). The improved catalytic performance ascribed to not only good mass diffusion and exchange, highly efficient light harvesting of 3DOM structure, but also the efficient charges separation of type Ⅱ heterojunction. The investigation on photocatalytic mechanism indicates that the glucose is mainly converted to gluconic acid and lactic acid, and the control reaction step is gluconic acid to lactic acid. The selectivity for gluconic acid on 3DOM CTO-ZCS is 85.65 %. Our work here proposes a green sustainable method to achieve highly efficient H 2 production and selective conversion of glucose to gluconic acid.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Scientific Reports
·
2016
·Vol. 6
·期 1
·1-7
·
IF 5.228
Qu Yongshui,Li Li,Wei Quanyuan,Huang Chongpin,Oleskowicz-Popiel Piotr,Xu Jian
Conversion of carbohydrate into 5-hydroxymethylfurfural (5- HMF), a versatile, key renewable platform compound is regarded as an important transformation in biomass-derived carbohydrate chemistry. A variety of ILs, not only acidic but also alkaline ILs, were synthesized and used as catalyst in the production of 5-HMF from disaccharide. Several factors including reaction temperature, IL dosage, solvent and reaction time,were found to influence the yield of 5-HMF from cellobiose. Of the ILs tested, hydroxy-functionalized ionic liquid (IL), 1-hydroxyethyl-3-methylimidazolium tetrafluoroborate ([AEMIM]BF 4 ) showed the highest catalytic activity and selectivity. 5-HMF yield of 68.71% from sucrose was obtained after 6 hrs at 160 °C. At the same condition with cellobiose as substrate, 5-HMF yield was 24.73%. In addition, 5-HMF also exhibited good stablity in this reaction system. Moreover, a kinetic analysis was carried out in both acidic and alkaline IL-catalyzed system, suggesting main side reaction in the conversion of fructose catalyzed by acidic and alkaline IL was polymerization of fructose and 5-HMF degradation, respectively.
研究领域:
生物质化学
·
催化化学
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Huiyi Fang,Zonghao Sheng,Wenxia Wang,Chuncheng Wei,Shuang Li,Xin Geng,Xiaowei Li,Nannan Zhu,Guangwu Wen,Shun Dong,Peng Wang
The protection for carbon fibers is crucial for carbon fiber-reinforced materials. Carbon coatings were prepared on carbon fibers through gelation, hydrothermal caramelization and pyrolysis, with glucose as precursor of carbon. The glucose-to-carbon conversion mechanism was explored, as well as the effect of high pressure in hydrothermal reactor and the catalytic role of KCl. The high pressure suppressed gas escape and was beneficial to the formation of dense carbon coating. The KCl promoted the generation of 5-HMF, thereby accelerated the glucose-to-caramel conversion. C f /ZrB 2 -SiC composites were prepared by introducing ZrB 2 -SiC slurry into the carbon fiber preform and hot press sintering. The carbon coating protected the carbon fibers from damage during sintering at high temperature. The carbon coating significantly improved the flexural strength, fracture toughness, and fracture work of C f /ZrB 2 -SiC composites from 122 MPa, 3.24 MPa‧m 1/2 , and 231.6 J/m 2 to 321 MPa, 5.87 MPa‧m 1/2 , and 567.1 J/m 2 , respectively.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Yueqing Wang,Guoqiang Ding,Xiaohai Yang,Hongyan Zheng,Yulei Zhu,Yongwang Li
The selective synthesis of furfural or hydroxymethylfurfural (HMF) from fructose on single catalyst (Beta zeolite, Hβ) is challenging task. However, in this study, selectivity of Hβ zeolite was discovered easily to tune by solvent effects. Strong solvent effects on the selectivity of fructose conversion were observed in different manners depending on the solvent used. It was shown that the coordinated state of framework aluminum, induced by solvent effects, has a major impact on the selectivity. The solvents with amide group were discovered to induce the reversible tetrahedral-octahedral framework aluminum transformation, but the configuration of aluminum was no influenced by other solvents such as γ-butyrolactone (GBL). Compared with other solvents, the GBL was not able to enhance turnover frequency (TOF) value of reaction but also suppress the degradation of furfural. Interestingly, a considerable yield of furfural (50.25%) was obtained combined with tetrahedral and octahedral framework aluminum active sites in GBL, while high selectivity of HMF (83.3%) was achieved in presence of single tetrahedral framework aluminum over Hβ in NMP.
研究领域:
催化化学
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
INORGANICA CHIMICA ACTA
·
2015
·
IF 2.046
Hui Liu,Chun Hua,Changhua Song,Shifeng Dai,Hongwei Wang,Wenshuai Zhu,Huaming Li
Some sulfur oxyacid salts with weak acidity or alkalinity, including Na 2 SO 4 , (NH 4 ) 2 SO 4 , (NH 4 ) 2 S 2 O 3 and Na 2 S 2 O 3 , were applied to the conversion of fructose to 5-hydroxymethylfurfural. The results indicated that (NH 4 ) 2 S 2 O 3 had excellent catalytic performance for the conversion of fructose. A desired HMF yield of 81.6% was obtained with only 5 mg (NH 4 ) 2 S 2 O 3 as the catalyst in [Bmim]Cl at 120 °C for 50 min. Furthermore, the HMF yield remained at 76.6% with 60 wt% water in the IL–water mixture solvent. In addition, the system of (NH 4 ) 2 S 2 O 3 and [Bmim]Cl exhibited a constant stability and activity, and a good HMF yield was maintained after nine recycles.
研究领域:
生物化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）