Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 782

会议视频 77

年份

2024 1

2023 58

2022 76

2021 94

2020 53

2019 24

2018 37

2017 39

2016 24

2015 27

2014 39

2013 36

2012 37

2011 38

2010 28

2009 25

2008 50

2007 46

2006 20

2005 24

展开︾

关键词

应用 11

人工智能 10

农业科学 8

智能制造 7

绿色化工 7

优化 6

碳中和 6

信息技术 5

钢结构 5

卫星应用 4

微地震监测 4

催化剂 3

大数据 3

能源 3

遗传算法 3

采油工程 3

颠覆性技术 3

2021全球十大工程成就 2

2022全球十大工程成就 2

展开︾

检索范围：

排序：展示方式：

A review on catalytic & non-catalytic bio-oil upgrading in supercritical fluids

Sainab Omar, Yang Yang, Jiawei Wang

《化学科学与工程前沿（英文）》 2021年第15卷第1期页码 4-17 doi: 10.1007/s11705-020-1933-x

摘要： This review article summarizes the key published research on the topic of bio-oil upgrading using catalytic and non-catalytic supercritical fluid (SCF) conditions. The precious metal catalysts Pd, Ru and Pt on various supports are frequently chosen for catalytic bio-oil upgrading in SCFs. This is reportedly due to their favourable catalytic activity during the process including hydrotreating, hydrocracking, and esterification, which leads to improvements in liquid yield, heating value, and pH of the upgraded bio-oil. Due to the costs associated with precious metal catalysts, some researchers have opted for non-precious metal catalysts such as acidic HZSM-5 which can promote esterification in supercritical ethanol. On the other hand, SCFs have been effectively used to upgrade crude bio-oil without a catalyst. Supercritical methanol, ethanol, and water are most commonly used and demonstrate catalyst like activities such as facilitating esterification reactions and reducing solid yield by alcoholysis and hydrolysis, respectively.

关键词： bio-oil upgrading supercritical review

HTML PDF 收藏

Improved degradation of azo dyes by lignin peroxidase following mutagenesis at two sites near the catalyticpocket and the application of peroxidase-coated yeast cell walls

Karla Ilić Đurđić, Raluca Ostafe, Olivera Prodanović, Aleksandra Đurđević Đelmaš, Nikolina Popović, Rainer Fischer, Stefan Schillberg, Radivoje Prodanović

《环境科学与工程前沿（英文）》 2021年第15卷第2期 doi: 10.1007/s11783-020-1311-4

摘要： Abstract • Mutations in Lignin peroxidase Trp171 environment improved azo dyes degradation. • Expression on yeast cell surface and cell lysis allowed reusability of biocatalyst. • Aga2-LiP chimeric variants were characterized. The enzymatic degradation of azo dyes is a promising alternative to ineffective chemical and physical remediation methods. Lignin peroxidase (LiP) from Phanerochaete chrysosporium is a heme-containing lignin-degrading oxidoreductase that catalyzes the peroxide-dependent oxidation of diverse molecules, including industrial dyes. This enzyme is therefore ideal as a starting point for protein engineering. Accordingly, we subjected two positions (165 and 264) in the environment of the catalytic Trp171 residue to saturation mutagenesis, and the resulting library of 104 independent clones was expressed on the surface of yeast cells. This yeast display library was used for the selection of variants with the ability to break down structurally-distinct azo dyes more efficiently. We identified mutants with up to 10-fold greater affinity than wild-type LiP for three diverse azo dyes (Evans blue, amido black 10B and Guinea green) and up to 13-fold higher catalytic activity. Additionally, cell wall fragments displaying mutant LiP enzymes were prepared by toluene-induced cell lysis, achieving significant increases in both enzyme activity and stability compared to a whole-cell biocatalyst. LiP-coated cell wall fragments retained their initial dye degradation activity after 10 reaction cycles each lasting 8 h. The best-performing mutants removed up to 2.5-fold more of each dye than the wild-type LiP in multiple reaction cycles.

关键词： Bioremediation Enzyme immobilization Protein engineering Yeast surface display.

HTML PDF 收藏

Mechanistic understanding of Cu-based bimetallic catalysts

You Han, Yulian Wang, Tengzhou Ma, Wei Li, Jinli Zhang, Minhua Zhang

《化学科学与工程前沿（英文）》 2020年第14卷第5期页码 689-748 doi: 10.1007/s11705-019-1902-4

摘要： Copper has received extensive attention in the field of catalysis due to its rich natural reserves, low cost, and superior catalytic performance. Herein, we reviewed two modification mechanisms of co-catalyst on the coordination environment change of Cu-based catalysts: (1) change the electronic orbitals and geometric structure of Cu without any catalytic functions; (2) act as an additional active site with a certain catalytic function, as well as their catalytic mechanism in major reactions, including the hydrogenation to alcohols, dehydrogenation of alcohols, water gas shift reaction, reduction of nitrogenous compounds, electrocatalysis and others. The influencing mechanisms of different types of auxiliary metals on the structure-activity relationship of Cu-based catalysts in these reactions were especially summarized and discussed. The mechanistic understanding can provide significant guidance for the design and controllable synthesis of novel Cu-based catalysts used in many industrial reactions.

关键词： copper bimetallic catalyst coordination modification mechanism catalytic application

HTML PDF 收藏

Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

《化学科学与工程前沿（英文）》 2021年第15卷第5期页码 1206-1216 doi: 10.1007/s11705-020-2017-7

摘要： In this work, the detailed oxygen reduction reaction (ORR) catalytic performance of M-N O (M= Fe, Co, and Ni; = 1–4) has been explored via the detailed density functional theory method. The results suggest that the formation energy of M-N O shows a good linear relationship with the number of doped O atoms. The adsorption manner of O on M-N O changed from end-on ( = 1 and 2) to side-on ( = 3 and 4), and the adsorption strength gradually increased. Based on the results for binding strength of ORR intermediates and the Gibbs free energy of ORR steps on the studied catalysts, we screened out two highly active ORR catalysts, namely Co-N O and Ni-N O , which possess very small overpotentials of 0.27 and 0.32 V, respectively. Such activities are higher than the precious Pt catalyst. Electronic structure analysis reveals one of the reasons for the higher activity of Co-N O and Ni-N O is that they have small energy gaps and moderate highest occupied molecular orbital energy levels. Furthermore, the results of the density of states reveal that the O doping can improve the electronic structure of the original catalyst to tune the adsorption of the ORR intermediates.

关键词： M-N-C catalyst oxygen doping oxygen reduction reaction catalytic activity density functional theory

HTML PDF 收藏

Effects of support acidity on the reaction mechanisms of selective catalytic reduction of NO by CH

Shicheng XU, Junhua LI, Dong YANG, Jiming HAO

《环境科学与工程前沿（英文）》 2009年第3卷第2期页码 186-193 doi: 10.1007/s11783-009-0016-5

摘要： The reaction mechanisms of selective catalytic reduction (SCR) of nitric oxide (NO) by methane (CH ) over solid superacid-based catalysts were proposed and testified by DRIFTS studies on transient reaction as well as by kinetic models. Catalysts derived from different supports would lead to different reaction pathways, and the acidity of solid superacid played an important role in determining the reaction mechanisms and the catalytic activities. Higher ratios of Br?nsted acid sites to Lewis acid sites would lead to stronger oxidation of methane and then could facilitate the step of methane activation. Strong Br?nsted acid sites would not necessarily lead to better catalytic performance, however, since the active surface NO species and the corresponding reaction routes were determined by the overall acidity strength of the support. The reaction routes where NO moiety was engaged as an important intermediate involved moderate oxidation of methane, the rate of which could determine the overall activity. The reaction involving NO moiety was likely to be determined by the step of reduction of NO. Therefore, to enhance the SCR activity of solid superacid catalysts, reactions between appropriate couples of active NO species and activated hydrocarbon intermediates should be realized by modification of the support acidity.

关键词： selective catalytic reduction (SCR) nitric oxide (NO) methane support acidity Br?nsted acid sites NO_y species

HTML PDF 收藏

Preparation of rare-earth metal complex oxide catalysts for catalytic wet air oxidation

LI Ning, LI Guangming, YAO Zhenya, ZHAO Jianfu

《环境科学与工程前沿（英文）》 2007年第1卷第2期页码 190-195 doi: 10.1007/s11783-007-0033-1

摘要： Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for CWAO of high concentration phenolcontaining wastewater were prepared by coprecipitation. The catalyst preparation conditions were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were characterized by Brunauer Emmett Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a low temperature (80?C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, COD, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would have a promising application in CWAO treatment of high concentration organic wastewater.

关键词： torch-atomic emission Brunauer Catalytic process stability

HTML PDF 收藏

Properties and catalytic mechanism of -glutamyltranspeptidase from NX-2

WANG Qian, YAO Zhong, XUN Zhijing, XU Xiaoying, XU Hong, WEI Ping

《化学科学与工程前沿（英文）》 2008年第2卷第4期页码 456-461 doi: 10.1007/s11705-008-0075-3

摘要： Since -glutamyltranspeptidase (GGT) especially catalyses the transfer of the -glutamyl moiety to a variety of amino acids and short peptides, GGT has important practical value for enzymatic synthesis of -glutamyl compounds. In this paper, the GGT produced from NX-2 was purified by a combination of ammonium sulfate fractionation and ion exchange chromatography, and the properties of purified GGT were investigated. At the conditions of pH 10.0, D-glutamine (D-Gln)/L-tryptophan (L-Trp) with a molar ratio of 5 : 7, a temperature 40°C and a reaction time of 4 h, a higher conversion rate of 42% was obtained. According to the time course, the catalytic mechanism of enzymatic synthesis of -D-glutamyl-L-tryptophan (-D-Gln-L-Trp) was discussed. It was demonstrated that the GGT can catalyze not only the reaction of transpeptidation, but also the irreversible hydrolysis of the products which results in the decrease of the yield of the products. The affinity parameter of GGT to D-Gln (Km) was 5.08 mmol·L and the maximum reaction rate of transpeptidation () was determined as 0.034 mmol·min·L, while the affinity parameter of GGT to -D-Gln-L-Trp (’) was 2.267 mmol·L, and the maximum reaction rate of hydrolysis (’) was 0.012 mmol·min·L.

关键词： catalytic mechanism mmol·min·L D-glutamine affinity parameter important practical

HTML PDF 收藏

Multi-stage ammonia production for sorption selective catalytic reduction of NO

Chen ZHANG, Guoliang AN, Liwei WANG, Shaofei WU

《能源前沿（英文）》 2022年第16卷第5期页码 840-851 doi: 10.1007/s11708-021-0797-1

摘要： Sorption selective catalytic reduction of nitrogen oxides (NO_x) (sorption-SCR) has ever been proposed for replacing commercial urea selective catalytic reduction of NO_x (urea-SCR), while only the single-stage sorption cycle is hitherto adopted for sorption-SCR. Herein, various multi-stage ammonia production cycles is built to solve the problem of relative high starting temperature with ammonia transfer (AT) unit and help detect the remaining ammonia in ammonia storage and delivery system (ASDS) with ammonia warning (AW) unit. Except for the single-stage ammonia production cycle with MnCl₂, other sorption-SCR strategies all present overwhelming advantages over urea-SCR considering the much higher NO_x conversion driven by the heat source lower than 100°C and better matching characteristics with low-temperature catalysts. Furthermore, the required mass of sorbent for each type of sorption-SCR is less than half of the mass of AdBlue for urea-SCR. Therefore, the multifunctional multi-stage sorption-SCR can realize compact and renewable ammonia storage and delivery with low thermal energy consumption and high NO_x conversion, which brings a bright potential for efficient commercial de-NO_x technology.

关键词： selective catalytic reduction (SCR) nitrogen oxides (NO_x) ammonia composite sorbent chemisorption

HTML PDF 收藏

Selective catalytic reduction of NO

Pavlo I. Kyriienko

《化学科学与工程前沿（英文）》 2020年第14卷第4期页码 471-491 doi: 10.1007/s11705-019-1847-7

摘要： Research results regarding selective catalytic reduction (SCR) of NO with ethanol and other C oxygenates as reductants over silver-alumina catalysts are summarized. The aspects of the process mechanism, nature of active sites, role of alumina and silver (especially in the formation of bifunctional active sites), effects of reductants and reaction conditions are discussed. It has been determined that key stages of the process include formation of reactive enolic species, their interaction with NO and formation of nitroorganic compounds which transform to NCO species and further to N . The results obtained over various silver-alumina catalysts demonstrate the perspectives of their application for reducing the level of nitrogen oxides in engine emissions, including in the presence of water vapor and sulfur oxides. Ways to improve the catalysts for the SCR of NO with C oxygenates are outlined.

关键词： SCR nitrogen oxides silver-alumina catalyst silver species ethanol oxygenates

HTML PDF 收藏

Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1399-1411 doi: 10.1007/s11705-023-2345-5

摘要： Three kinds of Ce-based catalysts (CePO₄, CeVO₄, Ce₂(SO₄)₃) were synthesized and used for the selective catalytic reduction (SCR) of NO by NH₃. NH₃-SCR performances were conducted in the temperature range of 80 to 400 °C. The catalytic efficiencies of the three catalysts are as follow: CePO₄ > CeVO₄ > Ce₂(SO₄)₃, which is in agreement with their abilities of NH₃ adsorption capacities. The highest NO conversion rate of CePO₄ could reach about 95%, and the catalyst had more than 90% NO conversion rate between 260 and 320 °C. The effect of PO₄^3–, VO₄^3– and SO₄^2– on NH₃-SCR performances of Ce-based catalysts was systematically investigated by the X-ray photoelectron spectroscopy analysis, NH₃ temperature programmed desorption, H₂ temperature programmed reduction and field emission scanning electron microscopy tests. The key factors that can enhance the SCR are the existence of Ce⁴⁺, large NH₃ adsorption capacity, high and early H₂ consumptions, and suitable microstructures for gas adsorption. Finally, CePO₄ and CeVO₄ catalysts also exhibited relatively strong tolerance of SO₂, and the upward trend about 8% was detected due to the sulfation enhancement by SO₂ for Ce₂(SO₄)₃.

关键词： CePO₄ CeVO₄ Ce₂(SO₄)₃ selective catalytic reduction NO removal

HTML PDF 收藏

effect of ion-exchanged K on the low-temperature hydrothermal stability of Cu/SAPO-34 and its synergic application

Chen Wang, Jun Wang, Jianqiang Wang, Meiqing Shen

《环境科学与工程前沿（英文）》 2021年第15卷第2期 doi: 10.1007/s11783-020-1322-1

摘要： Abstract • K+ hinder the structural degradation of Cu/SAPO-34 under humid condition<100°C. • K+ on Cu/SAPO-34 brings lower acidity and inferior SCR activity at high temperature. • Fe/Beta was used to compensate the low activity of Cu/SAPO-34 at high temperature. • The hybrid catalysts with KCu/SAPO-34 and Fe/Beta show a great potential for using. K ions were introduced onto Cu/SAPO-34 catalysts via the ion-exchange process in order to improve their stability under low-temperature hydrothermal aging. The changes in structure and copper-species contents of these catalysts upon hydrothermal aging were probed in order to investigate their effects on selective catalytic reduction (SCR) activity. For the fresh Cu/SAPO-34 catalysts, K ions had little influence on the chabazite framework but effected their acidities by exchanging with acid sites. After hydrothermal aging, the structural integrity and amount of active sites decreased on pure Cu/SAPO-34. While the K-loaded catalysts showed improved chabazite structure, acidity, and active site conservation with increasing K loading. However, although the 0.7 wt% K catalyst maintained the same crystallinity, active site abundance, and low-temperature SCR activity as the fresh catalyst upon aging, an apparent decrease in SCR activity at high temperature was observed because of the inevitable decrease in the number of Brönsted acid sites. To compensate for the activity disadvantage of K-loaded Cu/SAPO-34 at high temperature, Fe/Beta catalysts were co-employed with K-loaded Cu/SAPO-34, and a wide active temperature window of SCR activity was obtained. Thus, our study reveals that a combined system comprising Fe/Beta and K-loaded Cu/SAPO-34 catalysts shows promise for the elimination of NOx in real-world applications.

关键词： Selective catalytic reduction Cu/SAPO-34 catalyst Ion-exchanged K Low-temperature hydrothermal stability Fe/Beta catalyst

HTML PDF 收藏

synthesis of functional MFI zeolite materials: Method development, crystallization mechanisms, and catalytic

Zhaoqi Ye, Hongbin Zhang, Yahong Zhang, Yi Tang

《化学科学与工程前沿（英文）》 2020年第14卷第2期页码 143-158 doi: 10.1007/s11705-019-1852-x

摘要： As an important zeolite material, MFI zeolites, as well as their controllable synthesis, are of great interest in both basic and applied science. Among the developed synthetic approaches, the seed-induced method has gradually evolved into a facile, low-cost, and even green alternative to give zeolites the desirable physicochemical properties. In this review, we briefly summarize the development of seed-induced syntheses of diverse functional MFI zeolites, where the “living” seed crystals not only direct the formation of zeolitic framework but also function as special “templates” or “units” to fine-tune the zeolite materials with diverse sizes, shapes, compositions, morphologies and pore structures. Moreover, on the basis of their structural features and crystallization behaviors in seed-induced synthesis, we reveal the roles of seeds and discuss the related crystallization mechanisms including both classical and non-classical pathways. We also want to guide readers to investigate the structure-performance relationships between these functional MFI zeolite catalysts and suitable catalytic reactions.

关键词： seed-induced synthesis MFI zeolite synthesis mechanism catalytic property

HTML PDF 收藏

Tuning the catalytic selectivity in electrochemical CO

Jiafang XIE,Yuxi HUANG,Hanqing YU

《环境科学与工程前沿（英文）》 2015年第9卷第5期页码 861-866 doi: 10.1007/s11783-014-0742-1

摘要： Electrochemical conversion of CO to hydrocarbons can relieve both environmental and energy stresses. However, electrocatalysts for this reaction usually suffer from a poor product selectivity and a large overpotential. Here we report that tunable catalytic selectivity for hydrocarbon formation could be achieved on Cu nanomaterials with different morphologies. By tuning the electrochemical parameters, either Cu oxide nanowires or nanoneedles were fabricated and then electrochemically reduced to the corresponding Cu nanomaterials. The Cu nanowires preferred the formation of C H , while the Cu nanoneedles favored the production of more CH , rather than C H . Our work provides a facile synthetic strategy for preparing Cu-based nanomaterials to achieve selective CO reduction.

关键词： electrochemical CO₂ reduction Cu oxide nanostructure selectivity hydrocarbon formation

HTML PDF 收藏

Thermodynamic analysis of reaction pathways and equilibrium yields for catalytic pyrolysis of naphtha

《化学科学与工程前沿（英文）》 2022年第16卷第12期页码 1700-1712 doi: 10.1007/s11705-022-2207-6

摘要： The chain length and hydrocarbon type significantly affect the production of light olefins during the catalytic pyrolysis of naphtha. Herein, for a better catalyst design and operation parameters optimization, the reaction pathways and equilibrium yields for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins were analyzed thermodynamically. The results revealed that the thermodynamically favorable reaction pathways for n/iso-paraffins and cyclo-paraffins were the protolytic and hydrogen transfer cracking pathways, respectively. However, the formation of light paraffin severely limits the maximum selectivity toward light olefins. The dehydrogenation cracking pathway of n/iso-paraffins and the protolytic cracking pathway of cyclo-paraffins demonstrated significantly improved selectivity for light olefins. The results are thus useful as a direction for future catalyst improvements, facilitating superior reaction pathways to enhance light olefins. In addition, the equilibrium yield of light olefins increased with increasing the chain length, and the introduction of cyclo-paraffin inhibits the formation of light olefins. High temperatures and low pressures favor the formation of ethylene, and moderate temperatures and low pressures favor the formation of propylene. n-Hexane and cyclohexane mixtures gave maximum ethylene and propylene yield of approximately 49.90% and 55.77%, respectively. This work provides theoretical guidance for the development of superior catalysts and the selection of proper operation parameters for the catalytic pyrolysis of C_5–8 n/iso/cyclo-paraffins from a thermodynamic point of view.

关键词： naphtha catalytic pyrolysis reaction pathway equilibrium yield

HTML PDF 收藏

Preparation and catalytic performance of La0.8Sr0.2CoO3 supported on the mullite fiber ceramic

ZENG Lingke, LIU Yanchun, LIU Ping′an, WANG Hui, SHUI Anze, DUAN Bilin

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 372-376 doi: 10.1007/s11705-007-0067-8

摘要： The perovskite-type LaSrCoO supported on the mullite fiber porous ceramics was prepared by means of the impregnating method, and was then characterized by scanning electron microscopy (SEM) and X-ray diffraction (XRD); thus we can come to the conclusion that the perovskite-type composite oxidant can disperse on the surface of mullite fiber ceramics. The catalytic activity of the LaSrCoO for NO and CO was evaluated. The effect of the doped 0.1 wt-% PdCl on the catalytic activity of the perovskite-type LaSrCoO was also discussed. The results show that the conversion rates of NO and CO respectively reaches 74.5% and 99% at 601°C without doped Pd, and both reach 100% at 350°C with a little doped Pd.

关键词： porous conversion catalytic activity electron microscopy perovskite-type LaSrCoO

HTML PDF 收藏

标题作者时间类型操作

A review on catalytic & non-catalytic bio-oil upgrading in supercritical fluids

Sainab Omar, Yang Yang, Jiawei Wang

期刊论文

Improved degradation of azo dyes by lignin peroxidase following mutagenesis at two sites near the catalyticpocket and the application of peroxidase-coated yeast cell walls

Karla Ilić Đurđić, Raluca Ostafe, Olivera Prodanović, Aleksandra Đurđević Đelmaš, Nikolina Popović, Rainer Fischer, Stefan Schillberg, Radivoje Prodanović

期刊论文

Mechanistic understanding of Cu-based bimetallic catalysts

You Han, Yulian Wang, Tengzhou Ma, Wei Li, Jinli Zhang, Minhua Zhang

期刊论文

Probing the catalytic activity of M-N

Fan Ge, Qingan Qiao, Xin Chen, You Wu

期刊论文

Effects of support acidity on the reaction mechanisms of selective catalytic reduction of NO by CH

Shicheng XU, Junhua LI, Dong YANG, Jiming HAO

期刊论文

Preparation of rare-earth metal complex oxide catalysts for catalytic wet air oxidation

LI Ning, LI Guangming, YAO Zhenya, ZHAO Jianfu