APPLIED CATALYSIS A-GENERAL
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2018
·
IF 4.521
Liqin Wang,Heqin Guo,Qilong Xie,Jungang Wang,Bo Hou,Litao Jia,Jinglei Cui,Debao Li
Furfural is one of the most valuable biomass platform compounds which is typically prepared from hemicellulose. Conversion of cellulose and its derived hexoses, which are the most abundant resource in nature, to furfural, is a big challenge. The amount of the reactive form (fructofuranose) which was beneficial to the formation of furfural and HMF, was increased when the solvent transformed from water to γ-butyrolactone (GBL)-water. The GBL promoted the adsorption of fructose on HY. The transfer of fructose from the solution to the channels of HY was enhanced with the introducing of GBL in solvent. The HY zeolite with apertures of 7.4 Å was found to promote the formation of acyclic fructose from cyclic fructose (8.6 Å) in the synergy with GBL. The Brønsted acid sites in the channels of HY favored the selective cleavage of the C C bond in acyclic fructose to xylose, and promoted the following dehydration of xylose to furfural, simultaneously. The furfural yield was increased while the 5-hydroxymethylfurfural (HMF) yield was decreased with the decrease of the Brønsted acid sites density. The maximum furfural yield was 37.8% over HY-3, while the maximum HMF yield was 69.2% over HY-1 in the conversion of fructose in GBL-water solvent. In addition, the etherification of HMF was the main factor for the low HMF yield and carbon balance in fructose conversion in GBL-water solvent.
研究领域:
化学工程
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生物质转化
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DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 43
·24534-24540
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IF 2.936
Jin Tan,Haiyong Wang,Longlong Ma,Chenguang Wang,Qiying Liu,Qi Zhang,Minghong He
Several simple and effective solvents combined with Hβ zeolite were tested to selectively convert glucose into furfural and hydroxymethylfurfural in this work. The physicochemical properties of typically different polar aprotic solvents were compared. Tetrahydrofuran was found to be a suitable solvent in the selective conversion of glucose. The effect of reaction parameters, such as temperature, reaction time, water content, glucose dosage and protonic acid addition, on the product distribution were investigated in detail. Furfural and hydroxymethylfurfural could be selectively produced in this system, and the highest yields of furfural and hydroxymethylfurfural were up to 35.2% and 49.7% respectively. Furfural could be stable in a tetrahydrofuran medium when adding 5 wt% water in the absence of extra protonic acid. However, furfural production was extremely suppressed after addition of an acidic inorganic salt, which increased the yield of hydroxymethylfurfural. This investigation indicates a simple and feasible method to selectively produce furfural and hydroxymethylfurfural from renewable cellulosic carbohydrates.
研究领域:
化学工程
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可再生资源转化
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DOI
PubMed
高影响因子
Catalysts
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2019
·Vol. 9
·期 11
·886
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IF 3.444
Wei Wang,Shaoying Sun,Fengan Han,Guangyi Li,Xianzhao Shao,Ning Li
Diesel and jet fuel range cycloalkanes were obtained in ~84.8% overall carbon yield with cyclopentanone and furfural, which can be produced from hemicellulose. Firstly, 2,5-bis(furan-2-ylmethyl)-cyclopentanone was prepared by the aldol condensation/hydrogenation reaction of cyclopentanone and furfural under solid base and selective hydrogenation catalyst. Over the optimized catalyst (Pd/C-CaO), 98.5% carbon yield of 2,5-bis(furan-2-ylmethyl)-cyclopentanone was acquired at 423 K. Subsequently, the 2,5-bis(furan-2-ylmethyl)-cyclopentanone was further hydrodeoxygenated over the M/H-ZSM-5(Pd, Pt and Ru) catalyst. Overall, 86.1% carbon yield of diesel and jet fuel range cycloalkanes was gained over the Pd/H-ZSM-5 catalyst under solvent-free conditions. The cycloalkane mixture obtained in this work has a high density (0.82 g mL−1) and a low freezing point (241.7 K). Therefore, it can be mixed into diesel and jet fuel to increase their volumetric heat values or payloads.Keywords:high density fuel;cyclopentanone;furfural;aldol condensation;hydrodeoxygenation
研究领域:
能源化学
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催化反应工程
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DOI
高影响因子
TALANTA
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2015
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IF 3.545
Jiu-Feng Liu,Bi-Feng Yuan,Yu-Qi Feng
In this study, magnetic solid phase extraction coupled with in - situ derivatization (MSPE-ISD) was established for the determination of hexanal and heptanal in human urine. 2,4-Dinitrophenylhydrazine (DNPH) was used as the derivatization reagent that was adsorbed onto the surface of magnetite/silica/poly(methacrylic acid-co-ethylene glycol dimethacrylate) (Fe 3 O 4 /SiO 2 /P(MAA-co-EGDMA)). And then simultaneous extraction and derivatization of the aldehydes were performed on the DNPH-adsorbed Fe 3 O 4 /SiO 2 /P(MAA-co-EGDMA). The simple, rapid and sensitive determination of hexanal and heptanal can be accomplished within 9 min. Under optimized conditions, the limits of detection (LODs) were 1.7 and 2.5 nmol/L for hexanal and heptanal, respectively. The relative recoveries ranged from 72.8% to 91.4% with the intra- and inter-day relative standard deviations (RSDs) being less than 9.6%. Furthermore, the proposed method was successfully applied to determine endogenous hexanal and heptanal in human urine from healthy persons and lung cancer patients. The results showed the higher concentrations of hexanal and heptanal were observed in lung cancer patients compared to healthy controls. Thus, the developed MSPE-ISD method is suitable for the determination of aldehydes in urines.
研究领域:
分析化学
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医学诊断
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生物标志物研究
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DOI
PubMed
高影响因子
FOOD CHEMISTRY
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2022
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IF 9.231
Cong Chen,Fei Yu,Xinli Wen,Shuna Chen,Kaixi Wang,Feiquan Wang,Jianming Zhang,Yuanyuan Wu,Puming He,Youying Tu,Bo Li
Two major green leaf volatiles (GLVs) in tea that contribute greatly to tea aroma, particularly the green odor, are (E)-2-hexenal and (Z)-3-hexenal. Until now, their formation and related mechanisms during tea manufacture have remained unclear. Our data showed that the contents of (E)-2-hexenal and (Z)-3-hexenal increased more than 1000-fold after live tea leaves were torn. Subsequently, a new (Z)-3:(E)-2-hexenal isomerase (CsHI) was identified in Camellia sinensis . CsHI irreversibly catalyzed the conversion of (Z)-3-hexenal to (E)-2-hexenal . Abiotic stresses including low temperature, dehydration, and mechanical wounding, did not influence the (E)-2-hexenal content in intact tea leaves during withering, but regulated the proportions of (Z)-3-hexenal and (E)-2-hexenal in torn leaves by modulating CsHI at the transcript level. For the first time, this work reveals the formation of (E)-2-hexenal during tea processing and suggests that CsHI may play a pivotal role in tea flavor development as well as in plant defense against abiotic stresses.
研究领域:
植物学
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食品科学
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分子生物学
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DOI
PubMed
高影响因子
BRAZILIAN JOURNAL OF CHEMICAL ENGINEERING
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2023
·
IF 1.2
He Yuntao,Guo Xiaxin,Qiao Luyang,Ye Runping,Zong Shanshan,Cao Xinyi,Cheng Jiankai,Zhou Zhangfeng,Yao Yuangen
Rh complexes are considered as the most promising catalysts for formaldehyde hydroformylation since they can achieve higher yields of glycolaldehyde under mild conditions. Although heterogeneous catalysts are convenient to separate, Rh-based heterogeneous catalysts usually have limited catalytic activity in hydroformylation of formaldehyde. Here, four different supports (Al 2 O 3 , SiO 2 , SBA-15 and HMS), loaded with Rh by impregnation method, have been developed for formaldehyde hydroformylation. The physico-chemical properties of the materials have been investigated by means of complementary techniques. Due to the presence of more oxidized rhodium species and stronger metal support interactions, the silica-based catalysts achieved higher formaldehyde conversion and glycolaldehyde selectivity than Rh/Al 2 O 3 . Moreover, SBA-15 and HMS zeolites were synthesized by adjusting the structure of the silica support. Thus, the selectivity of 94.8% for glycolaldehyde and a remarkable glycolaldehyde yield of 52.7% over Rh/SBA-15 catalyst was obtained due to its larger surface area, suitable pore structures and higher dispersion of Rh species.
研究领域:
化学工程
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催化材料科学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2024
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IF 5.7
Yuqing Zhong,Chen Yang,Yongling Lu,Lishuang Lv
Acrolein (ACR), methylglyoxal (MGO), and glyoxal (GO) are a class of reactive carbonyl species (RCS), which play a crucial role in the pathogenesis of chronic and age-related diseases. Here, we explored a new RCS inhibitor (theanine, THE) and investigated its capture capacity on RCS in vivo by human experiments. After proving that theanine could efficiently capture ACR instead of MGO/GO by forming adducts under simulated physiological conditions, we further detected the ACR/MGO/GO adducts of theanine in the human urine samples after consumption of theanine capsules (200 and 400 mg) or green tea (4 cups, containing 200 mg of theanine) by using ultraperformance liquid chromatography–time-of-flight–high-resolution mass spectrometry. Quantitative assays revealed that THE-ACR, THE-2ACR-1, THE-MGO, and THE-GO were formed in a dose-dependent manner in the theanine capsule groups; the maximum value of the adducts of theanine was also tested. Furthermore, besides the RCS adducts of theanine, the RCS adducts of catechins could also be detected in the drinking tea group. Whereas, metabolite profile analysis showed that theanine could better capture RCS produced in the renal metabolic pathway than catechins. Our findings indicated that theanine could reduce RCS in the body in two ways: as a pure component or contained in tea leaves.
研究领域:
药理学
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营养学
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生物化学
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代谢组学
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产品关联
DOI
PubMed
高影响因子
ChemCatChem
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2024
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IF 3.8
Mingwei Wang,Zhen Shi,Zhiquan Yu,Shushuang Li,Zhixin Zhang,Feng Wang
Graphical The HCHO-acetaldehyde condensation is a typic aldol reaction and a critical step to produce 1,3-propanediol from methanol and ethanol. The cross condensation of HCHO and acetaldehyde to acrolein has been conducted over MgO/SiO 2 catalyst, which shows the synergistic catalysis by the acidic sites (Mg-O-Si structure) and basic sites (Mg-O-Mg structure) for activation of HCHO and acetaldehyde, respectively. Acid-base synergistic catalysis greatly enhances the performance of MgO-based catalysts in the Aldol condensation. In this paper, the effect of acid-base strength/concentration/proportion and the synergistic catalysis on the performance of cross condensation between HCHO and acetaldehyde were studied. The NH 3 /CO 2 -TPD results indicated that the weak acidic sites combined with the medium basic sites were beneficial for the cross condensation of formaldehyde and acetaldehyde. The loading of MgO nanocrystals on SiO 2 induced the generation of new acidic sites (Mg-O-Si). Combined with the inherent basic sites (Mg-O-Mg) and Mg-O-Si, the acid-base bifunctions sites could catalyze the cross condensation of HCHO and acetaldehyde synergistically. The appropriate proportion of acidic/basic sites (10/1) was critical for the cross condensation in the presence of vast water in formalin. The effect of reaction parameters, including molar ratio of substrates, reaction temperature, linear velocity and weight hourly space velocity, were investigated for the cross condensation. The results showed that 10 wt% MgO/SiO 2 catalysts exhibited the highest catalytic activity (57.9% conversion of acetaldehyde and 84.3% selectivity of acrolein) under the optimal reaction parameters among the investigated catalysts. The catalytic performance of MgO/SiO 2 could be recovered after in situ regeneration in air to remove the carbon deposition.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
FOOD SCIENCE AND BIOTECHNOLOGY
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2025
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IF 3.1
Tan Jin-Ming,Cui Rui,Hu Teng-Gen,Wu Hong
In order to improve the antifungal activity of natural fungicides to control the fungal contamination on bread products, the synergistic combination of cinnamaldehyde with citral (S CC ) against main bread spoilage fungi ( Aspergillus niger and Penicillium citrinum ) was screened. Compared to the single MICs of cinnamaldehyde and citral, the MICs of them against both fungi were significantly reduced by 74–87% when presented in S CC . In vitro tests demonstrated that S CC completely inhibited the spore germination and mycelial growth of both fungi at its MIC. Mechanistic investigations revealed that S CC caused severe cellular membrane damage and disrupted the intracellular redox homeostasis in both fungi. In situ tests showed S CC significantly extended the shelf life of bread by 9 days without adversely affecting the sensory flavor and quality of the bread. These results indicated that S CC is potential as a natural preservative in baked products.
研究领域:
食品科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2025
·
IF 2.8
Ruiyu Yuan,Yi Yang,Zhenhao Yao,Kan Zhang
In this study, we used vanillin and furfurylamine from renewable resources as starting materials and successfully synthesized an innovative derivative of bisbenzoxazine (MH-fa) using the Mannich reaction. We characterized the chemical structure of the newly synthesized bisbenzoxazine compound using high-resolution mass spectrometry (HR-MS) technology. The results of nuclear magnetic resonance spectroscopy (NMR) and Fourier transform infrared spectroscopy analysis (FT-IR) confirmed the successful synthesis of the target compound. The synthesis of the benzoxazine copolymer (MH-fa-co-DDM-BMI) was achieved by leveraging the reversibility of the Diels–Alder reaction between the MH-fa monomer and 4,4′-bismaleimide diphenylmethane (DDM-BMI). In addition, the investigation into the polymerization behavior of benzoxazine monomer and its corresponding main-chain copolymer was conducted employing differential scanning calorimetry (DSC) along with in situ FT-IR. We studied the thermal stability and combustion performance of two samples using thermogravimetric analysis (TGA) and microscale combustion calorimetry (MCC). The results revealed that the bio-based bisbenzoxazine exhibited excellent heat resistance and flame retardancy. Specifically, poly(MH-fa) exhibits a T d10 value of 350°C and a Y c value of 62.3% at 800°C. Furthermore, the material exhibits an extremely low heat release rate (20.4 J g −1 K −1 ), highlighting its potential applications in the field of high-efficiency flame retardant materials.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2018
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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
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绿色化学
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DOI
高影响因子
JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2019
·Vol. 95
·期 3
·719-729
·
IF 2.659
Siqi Jiang,Xianming Zhang,Yufeng Hu,Liuyi Yin,Jianguang Qi,Chunxiao Ren,Shuqin Mo
BACKGROUND Trioxane (C 3 H 6 O 3 ) is industrially produced from aqueous formaldehyde (HCHO) solutions through catalytic distillation catalyzed by sulfuric acid (H 2 SO 4 ). Optimizing industrial process of the synthesis and developing new catalysts require a reliable model for the vapor–liquid equilibria in reaction mixture HCHO–C 3 H 6 O 3 –H 2 SO 4 – H 2 O and a deep understanding of the role of H 2 SO 4 in the industrial production of trioxane. RESULTS Here the Maurer and co-workers's model and the LIFAC model along with their model parameters were invoked to develop such a model. The vapor–liquid equilibrium data in HCHO–C 3 H 6 O 3 –H 2 SO 4 –H 2 O and HCHO–salt–H 2 O were systematically measured and utilized to determine the newly introduced model parameters. The model thus-established provides a reliable method for calculating and predicting the vapor–liquid and chemical equilibria data in HCHO–C 3 H 6 O 3 –H 2 SO 4 – H 2 O and HCHO–salt–H 2 O. CONCLUSIONS The prediction results uncover that, in addition to its ability to accelerate the reaction, the catalyst H 2 SO 4 has strong abilities to increase the activity of ‘real’ reactant for trioxane synthesis and to promote the phase separation that is very important for drastically increasing the yield of trioxane, reducing the energy requirement for the trioxane synthesis, and decreasing the formation of the by-product formic acid. © 2019 Society of Chemical Industry
研究领域:
化学工程
·
工业催化
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）