JOURNAL OF CHEMICAL TECHNOLOGY AND BIOTECHNOLOGY
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2019
·Vol. 95
·期 3
·719-729
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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
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工业催化
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DOI
高影响因子
CATALYSIS LETTERS
·
2020
·Vol. 151
·期 6
·1834-1841
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IF 2.482
Feng Xiaoqing,Zhang Lin,Zhu Xuan,Xia Yan,Ma Cuiluan,Liang Jianguang,He Yu-Cai
Furfurylamine is an important furfural-upgrading biobased chemical for the production of pharmaceuticals, biofuels, fibers, additives, polymers, etc. In one-pot reaction system, biomass was tandemly catalyzed to furfurylamine with aluminium-based alkaline-treated graphite (Al-AG) catalyst and recombinant ω-transaminase biocatalyst. Al-AG (3.6 wt%) catalyzed corncob (75.0 g/L) to 110.0 mM furfural at 56.8% yield (based on xylan in corncob) in γ-valerolactone–water (1:4, v:v; pH 1.0) for 40 min at 180 °C. The pH-adjusted corncob-slurry (pH 7.5) containing furfural were catalyzed to furfurylamine at high yield with γ-valerolactone-tolerant Aspergillus terreus ω-transaminase biocatalyst at 35 °C using isopropylamine (3 mol isopropylamine/mol furfural) as amine donor. Such an efficient and sustainable approach for catalytic conversion of biomass to high-value-added biobased furfurylamine was successfully established in tandem reaction with Al-AG and ω-transaminase biocatalyst. Graphic Abstract
研究领域:
生物化学
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催化化学
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可再生资源
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DOI
高影响因子
ACS Applied Polymer Materials
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2025
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IF 4.7
Ziqi Zhu,Pei Yang,Wentao Huang,Xiaoyan Zhou
Modifications of urea-formaldehyde (UF) resin to achieve better bonding performance and lower formaldehyde emission are still an alluring task in the wooden composite industry. Herein, by strategically constructing a photocatalytic oxidation system relying on carbon dot-catalyzed peroxymonosulfate (PMS) activation, we confirmed that Kraft lignin can be readily oxidized to potent modifiers for improving the bonding performance of low-molar-ratio UF resin (F/U = 0.95). We found that the oxidation system consisting of carbon dots and PMS in a mass ratio of 1:20 revealed optimal efficiency in the oxidative valorization of lignin by primary cleavage of β–O–4 linkages, resulting in a remarkable reduction of molecular weight from 2026 to 679 Da. Meanwhile, lignin side-chain oxidation triggered by radicals (mainly involving sulfate radicals) also contributed largely to the transformation of S units to G and H units via demethoxylation, and the reaction patterns conferred the oxidation products an increased amount of aliphatic OH and phenolic OH. In comparison with untreated lignin, the lignin-degraded fragments promised relatively higher hydroxymethylation efficiency and enhanced chemical compatibility in the UF resin synthesis system, fostering the formation of copolymers containing phenolic-like moieties and branched polymer structures. Profiting from this structurally homogeneous modification of oxidized lignin, the copolymer resin not only revealed comparable storage stability to the UF resin but also possessed enhanced bonding performance on the premise of rather low formaldehyde emission, and plywood panels bonded with the lignin-modified resin exhibited a higher tensile shear strength of 0.81 MPa, which was a 58.8% increase with reference to the UF resin-bonded panels, and as a result complied with the relevant national standard (≥0.7 MPa). Overall, the lignin photocatalytic oxidation strategy proposed in our study would open a new avenue for providing biobased and potent modifiers in the production of wood adhesives.
研究领域:
林业科学
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材料科学
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DOI
高影响因子
Journal of Applied Spectroscopy
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2018
·Vol. 85
·期 1
·84-89
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IF 0.611
Zhang J.,Xia T.,Chen Q.,Sun Q.,Deng Y.,Wang C.
The characteristic absorption spectra of paraformaldehyde and metaldehyde in the terahertz frequency region are obtained by terahertz time-domain spectroscopy (THz-TDS). In order to reduce the absorption of terahertz (THz) wave by water vapor in the air and the background noise, the measurement system was filled with dry air and the measurements were conducted at the temperature of 24°C. Meanwhile, the humidity was controlled within 10% RH. The THz frequency domain spectra of samples and their references from 0 to 2.5 THz were analyzed via Fourier transform. The refractive index and absorption coefficients of the two aldehydes were calculated by the model formulas. From 0.1 to 2.5 THz, there appear two weak absorption peaks at 1.20 and 1.66 THz in the absorption spectra of paraformaldehyde. Only one distinct absorption peak emerges at 1.83 THz for metaldehyde. There are significant differences between the terahertz absorption coefficients of paraformaldehyde and metaldehyde, which can be used as "fingerprints" to identify these substances. Furthermore, the relationship between the average absorption coefficients and mass concentrations was investigated and the average absorption coefficient–mass concentration diagrams of paraformaldehyde and metaldehyde were shown. For paraformaldehyde, there is a linear relationship between the average absorption coefficient and the natural logarithm of mass concentration. For metaldehyde, there exists a simpler linear relationship between the average absorption coefficient and the mass concentration. Because of the characteristics of THz absorption of paraformaldehyde and metaldehyde, the THz-TDS can be applied to the qualitative and quantitative detection of the two aldehydes to reduce the unpredictable hazards due to these substances.
研究领域:
化学
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光谱学
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DOI
高影响因子
MOLECULES
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2025
·Vol. 30
·期 6
·1254
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IF 4.6
Yuexia Qin,Zhuyu Zheng,Di Liu,Shuhua Sun,Xiaolei Zhao,Lei Lv,Dengyu Xie,Zhonghui Han,Jinxing He
The effects of furfural and 5-methyl-2-furfural produced by the Maillard reaction on PhIP formation were investigated in chemical models and roasted pork patties. In the chemical models, the results indicated that increasing levels of furfural (r = −0.7338, R2= 0.9557) and 5-methyl-2-furfural (r = −0.7959, R2= 0.9864) significantly reduced PhIP formation, displaying a strong linear correlation. The effects of furfural and 5-methyl-2-furfural on the precursors of phenylalanine (Phe) and phenylacetaldehyde showed a significant reduction in the Phe level, while the level of phenylacetaldehyde was not increased. In addition, neither furfural nor 5-methyl-2-furfural could significantly reduce creatinine or PhIP. Further mechanism studies showed that furfural (5-methyl-2-furfural) directly captured Phe to form the corresponding Schiff base compounds a (2-((furan-2-ylmethylene) amino)-3-phenylpropanoic acid) and b (2-(((5-methylfuran-2-yl)methylene)amino)-3-phenylpropanoic acid). This process reduced the production of phenylacetaldehyde, thereby inhibiting the PhIP formation pathway. More importantly, these two compounds were detected in roasted pork patties to which glucose was added. The above pathway was finally confirmed in roasted pork patties. These results revealed that furfural and 5-methyl-2-furfural, formed during the Maillard reaction, play a significant role in inhibiting the formation of PhIP by reacting with Phe.
研究领域:
食品科学
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营养学
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毒理学
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产品关联
DOI
PubMed
高影响因子
FLUID PHASE EQUILIBRIA
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2017
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IF 2.473
Weiting Ma,Yufeng Hu,Haiyan Wang,Di Zhao
Formaldehyde is an important C1 synthon used in the chemical industry. Formaldehyde is mainly used in aqueous solutions. Solid precipitation from these solutions in the form of poly(oxymethylene) glycols impedes many technical processes. Acids, ionic liquids , and salts have been widely used as catalysts and additives in many technical processes using formaldehyde solutions as reactants. Few data are available in literature on solubility of formaldehyde in aqueous solution containing acids, ionic liquids, and salts. In the present work solubility data is reported for temperatures between 58 °C and 87 °C to investigate the effect of typical acids {H 2 SO 4 , H 3 PO 4 , CH 3 SO 3 H, CF 3 SO 3 H, C 6 H 5 SO 3 H, C 7 H 7 SO 3 H, C 8 H 9 SO 3 H, C 10 H 16 SO 4 or H 4 [Si(W 3 O 10 ) 4 ]; the acid concentration is 0.10 mol (kg formaldehyde aqueous solution) −1 }, imidazolium ionic liquids {[mim][HSO 4 ], [mim][CF 3 SO 3 ], [C 3 Smim][CH 3 SO 3 ] or [C 3 Smim][CF 3 SO 3 ]; [mim] + and [C 3 Smim] + stand for 1-methylimidazolium and 1-propylsulfonic-3-methylimidazolium cations; the concentration of the ionic liquid is 0.10 mol (kg formaldehyde aqueous solution) −1 }, and salts [NaCl, KCl, LiCl, MgCl 2 , ZnCl 2 , CH 3 SO 3 Na, CF 3 SO 3 Na, C 6 H 5 SO 3 Na, (C 2 H 5 ) 4 NBr or ZTS (1-methylimidazolium propanesulfonate); the concentration of the former nine salts is 0.40 mol (kg formaldehyde aqueous solution) −1 , and the ZTS concentrations are 0.10 and 0.15 mol (kg formaldehyde aqueous solution) −1 , respectively] on the solubility of formaldehyde in aqueous solutions. The results indicate that most acid catalysts and additive salts considered show salting-out effect. More importantly, the acids and salts that can be used as the catalysts and additive salts for trioxane and have salting-in effect are reported. The influence of the structural characteristics of the acids, ionic liquids and salts that were added on their salting-in/out effect is briefly discussed.
研究领域:
化学工程
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工业化学
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DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
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2022
·Vol. 46
·期 38
·18366-18373
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IF 3.925
Jinfa Yu,Xiangying Sun,Yiyang Chen
A fluorescent sensor array based on three kinds of carbon dots (CDs) were fabricated to discriminate hydroxybenzaldehyde and nitrobenzaldehyde isomers. Based on the Schiff base reaction, carbon dots with amino groups on the surface were designed. Fluorescence quenching of CDs occurred when hydroxybenzaldehyde and nitrobenzaldehyde isomers were combined with CDs. The sensor array showed different fluorescence patterns for each hydroxybenzaldehyde and nitrobenzaldehyde isomer in terms of fluorescence intensity change F/F0, which was further analyzed by principal component analysis (PCA). Finally, the fluorescent sensor array behaved well in differentiating and identifying hydroxybenzaldehyde and nitrobenzaldehyde isomers in aqueous solutions and distinguishing binary mixtures.
研究领域:
分析化学
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材料科学
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DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
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2023
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IF 5.7
Huang Lizhen,Bian Zelun,Li Dalin,Cheng Xin,Luo Xiaolin,Shuai Li,Liu Jing
Biobased furfural is a sustainable alternative to petrochemical intermediates for bulk chemicals and fuel production. However, existing methods for the conversion of xylose or lignocelluloses in mono-/bi-phasic systems to furfural involve non-selective sugar isolation or lignin condensation, limiting the valorisation of lignocelluloses. Herein, we used diformylxylose (DFX), a xylose derivative that is formed during the lignocellulosic fractionation process with formaldehyde protection, as a substitute for xylose to produce furfural in biphasic systems. Under kinetically optimized conditions, over 76 mol% of DFX could be converted to furfural in water-methyl isobutyl ketone system at a high reaction temperature with a short reaction time. Finally, isolation of xylan in eucalyptus wood as DFX with formaldehyde protection followed by converting DFX in a biphasic system gave a final furfural yield of 52 mol% (on the basis of xylan in wood), which was more than two times of that without formaldehyde. Combined with the value-added utilization of formaldehyde-protected lignin, this study would enable the full and efficient utilization of lignocellulosic biomass components and further improve the economics of the formaldehyde protection fractionation process.
研究领域:
化学工程
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可持续化学
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生物化学工程
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产品关联
DOI
PubMed
高影响因子
CHINESE CHEMICAL LETTERS
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2010
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IF 0.643
Jing Cao,Jun Xiang Feng,Yong Xiang Wu,Ya Ya Tuo
“One-step” method for the synthesis of secondary aliphatic amine substituted nitrobenzaldehyde was developed. In the presence of Pd catalyst, halogenated nitrobenzaldehyde could be smoothly coupled with secondary aliphatic amine to give the target product in hexamethylphosphamide (HMPT) media without the protection of aldehyde groups.
研究领域:
有机化学
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药物化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Fang Yuan,Jialin Liang,Shixuan Wang,Jiajia Wang,Bo Chen,Gaofeng Wang,Chunquan Li,Zhiming Sun
Herein, in-situ self-assembly of ZIF-67 derivative on the surface of stilbite and the doping of Ni ions into the Co 3 O 4 lattice were simultaneously achieved through a one-step calcination method. The obtained Ni-doped Co 3 O 4 /stilbite (Ni-Co-AS) exhibited efficient photo-assisted thermal catalytic purification of formaldehyde (HCHO). The results showed that after being regulated by Ni-doped, the Ni-Co-AS composite could achieve efficient photo-assisted thermal catalytic degradation of HCHO driven solely by light. The HCHO removal rate and mineralization rate could reach 93.04 % and 88.60 % within 3 h, respectively. In addition, in order to further improve the photothermal conversion performance of Ni-Co-AS, the composite fiber felt (Ni-Co-AS/F) was prepared from Ni-Co-AS. The conditional experiments show that thermal catalysis is the main mechanism in the photothermal catalytic degradation of formaldehyde by Ni-Co-AS/F. Compared to the pure thermal catalysis (180℃), the presence of light helps to reduce the reaction temperature (120℃) and plays a role in co-catalysis. Ni-Co-AS/F could achieve a higher mineralization rate than that of Ni-Co-AS composite (91.66 %) within 3 h due to the better dispersion and quantum transmission efficiency. In dynamic and long-term degradation experiments, the Ni-Co-AS/F exhibited excellent catalytic performance under the appropriate temperature (35 ± 0.5℃) and humidity (45 ± 3 %) required for the HCHO degradation. This work could effectively provide an efficient and sustainable catalytic material for air pollution control.
研究领域:
环境催化
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材料科学
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纳米技术
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空气污染控制
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2016
·
IF 4.758
Luyu Wang,Zhaoxi Wang,Qun Xiang,Yang Chen,Zhiming Duan,Jiaqiang Xu
In order to construct highly sensitive and stable QCM gas sensor, we present an innovative strategy. Firstly, we employ a physical vapor deposition (PVD) method to coat a thin layer of copper on the surface of QCM silver electrode. Then, a novel metal complex as sensing material, [Cu(DDS) 2 (Cl) 2 (MeOH) 2 ], is grown in-situ on the copper layer to ensure a strong coupling between metal complex sensing materials and QCM electrode. The sensing material is characterized through following instruments: elemental analysis, single crystal XRD, SEM, PXRD, IR spectra and TGA. The sensing test results indicate that the QCM sensor exhibit high sensitivity and selectivity toward gaseous formaldehyde because of a reversible interaction between amino group and HCHO molecule. The detection limit reaches down to 50 ppb. This implies the facile-fabricated sensor has a great potential in the area of rapid, stable, sensitive, and selective formaldehyde on-site detection. Based on the temperature-varying micro-gravimetric experiment, enthalpy change is quantitatively obtained, which indicates that the interaction between the complex and HCHO molecules belongs to chemical adsorption. The values of ΔH calculated by Gaussian 09 indicate that chemical adsorption between NH 2 group and aldehyde group play a leading role in detecting selectively formaldehyde gas.
研究领域:
材料科学
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环境监测
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分析化学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
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2018
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IF 5.807
Tingwei Zhang,Wenzhi Li,Shengxin An,Feng Huang,Xinzhe Li,Jingrong Liu,Gang Pei,Qiying Liu
In this work, p-hydroxybenzenesulfonic acid-formaldehyde resin acid catalyst (MSPFR), was synthesized by a hydrothermal method, and employed for the furfural production from raw corn stover. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), N 2 adsorption-desorption, elemental analysis (EA), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT-IR) were used to characterize the MSPFR. The effects of reaction time, temperature, solvents and corn stover loading were investigated. The MSPFR presented high catalytic activity for the formation of furfural from corn stover. When the MSPFR/corn stover mass loading ratio was 0.5, a higher furfural yield of 43.4% could be achieved at 190 °C in 100 min with 30.7% 5-hydroxymethylfurfural (HMF) yield. Additionally, quite importantly, the recyclability of the MSPFR for xylose dehydration is good, and for the conversion of corn stover was reasonable.
研究领域:
生物化学
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催化化学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）