资源类型

期刊论文 663

年份

2024 1

2023 51

2022 44

2021 54

2020 36

2019 44

2018 41

2017 34

2016 25

2015 31

2014 27

2013 24

2012 27

2011 27

2010 29

2009 33

2008 40

2007 41

2006 5

2005 6

展开 ︾

关键词

COVID-19 2

三十烷醇 2

催化剂 2

催化裂化 2

催化裂解 2

内禀尺度 2

冷凝水闪蒸 2

动力气垫 2

地效翼船 2

尺寸效应 2

水稻 2

32 m箱梁 1

ADV 1

ANSYS/LS-DYNA 1

CO 1

Casimir效应 1

Cu(Inx 1

DQP漂白 1

Dirac理论 1

展开 ︾

检索范围：

排序： 展示方式：

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 PO43–, VO43– and SO42– 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 K and Ca on catalytic activity of Mn-CeO

Boxiong SHEN, Lidan DENG, Jianhong CHEN

《环境科学与工程前沿（英文）》 2013年 第7卷 第4期   页码 512-517 doi: 10.1007/s11783-013-0519-y

摘要： Mn-CeO /Ti-pillared clay (PILC) is an attractive catalyst for selective catalytic reduction of NO at low temperature because of its low cost. The poisoning of K and Ca on the catalyst of Mn-CeO /Ti-PILC is an important problem because K and Ca are always in presence in flue gas. To investigate the effect of K and Ca on the physicochemical characters of the catalysts, the techniques of NH -temperature programmed desorption (TPD), H -temperature programmed reduction (TPR), and X-ray photoelectron spectroscopy (XPS) were used to analyze the fresh and deactivated catalysts of Mn-CeO /Ti-PILC. (Ca)Mn-CeO /Ti-PILC and (K)Mn-CeO /Ti-PILC are denoted for the dopes of the catalyst of Mn-CeO /Ti-PILC with Ca and K, respectively. The activities of Mn-CeO /Ti-PILC, (Ca)Mn-CeO /Ti-PILC and (K)Mn-CeO /Ti-PILC for NH -selective catalytic reduction (SCR) reaction at low temperature were investigated. The results showed that with the dopes of K and Ca on the catalysts, the SCR activities of the catalysts decreased greatly, and K exhibited more poisoning effect than Ca. With the dopes of K and Ca, the acidity, the redox property and chemisorbed oxygen on the surfaces of the catalysts were decreased, which resulted in a decreasing in SCR activity.

关键词： Mn-CeOx/Ti-pillared clay (PILC)     low-temperature selective catalytic reduction (SCR)     K and Ca poisoning effect    

HTML PDF 收藏

Promoting effect of Zr on the catalytic combustion of methane over Pd/γ-Al

Hongbo NA,Tianle ZHU,Zhiming LIU,Yifei SUN

《环境科学与工程前沿（英文）》 2014年 第8卷 第5期   页码 659-665 doi: 10.1007/s11783-013-0613-1

摘要： The effect of Zr on the catalytic performance of Pd/γ-Al O for the methane combustion was investigated. The results show that the addition of Zr can improve the activity and stability of Pd/γ-Al O catalyst, which, based on the catalyst characterization (N adsorption, XRD, CO-Chemisorption, XPS, CH -TPR and O -TPO), is ascribed to the interaction between Pd and Zr. The active phase of methane combustion over supported palladium catalyst is the Pd /Pd mixture. Zr addition inhibits Pd aggregation and enhances the redox properties of active phase Pd / Pd . H reduction could effectively reduce the oxidation degree of Pd species and regenerate the active sites (Pd / Pd ).

关键词： Pd-Zr/Al2O3     methane     catalytic combustion     catalyst regeneration    

HTML PDF 收藏

Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

《化学科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 176-180 doi: 10.1007/s11705-008-0026-z

摘要： Cellulose, one of the important components of biomass, was gasified in supercritical water to produce hydrogen-rich gas in an autoclave which was operated batch-wise under high-pressure. KCO and Ca(OH) were selected as the catalysts (or promoters). The temperature was kept between 450°C and 500°C while pressure was maintained at 24–26 MPa. The reaction time was 20 min. Experimental results showed that the two catalysts had good catalytic effect and optimum amounts were observed for each catalyst. When 0.2 g KCO was added, the hydrogen yield could reach 9.456 molkg which was two times of the H amount produced without catalyst. When 1.6 g Ca(OH) was added, the H yield was 8.265 molkg which is lower than that obtained using KCO as catalyst but is still 1.7 times that achieved without catalyst. Comparing with the results obtained using KCO or Ca(OH) alone, the use of a combination of KCO and Ca(OH) could increase the H yield by up to 2.5 times that without catalyst and 25% and 45% more than that obtained using KCO and Ca(OH) alone, respectively. It was found that methane was the dominant product at relatively low temperature. When the temperature was increased, the methane reacts with water and is converted to hydrogen and carbon dioxide.

关键词： reaction     temperature     combination     catalytic effect     dominant product    

HTML PDF 收藏

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

《环境科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 482-487 doi: 10.1007/s11783-007-0077-2

摘要： Catalytic ozonation of aqueous solutions of oxalic acid was examined in the presence of graphite-supported platinum catalysts. The catalytic activity of graphite was significantly enhanced by loading platinum. The removal efficiency of oxalic acid was 3.0%, 47.6% and 99.3% for ozonation alone, graphite catalytic ozonation and Pt/graphite catalytic ozonation in 30 min under the experimental condition, respectively. The influence of support pretreatment, solvent, impregnation time, platinum loading amount and reduction temperature on the activity of Pt/graphite catalyst was investigated. The pretreatment of graphite support had no effect on activity improvement of Pt/graphite catalyst. Solvent and impregnation time also had no great effect on the activity. Platinum loading amount and reduction temperature influenced the catalyst activity significantly. The optimal catalytic performance of Pt/graphite was obtained when 1.0% platinum loading and 623 K of reduction temperature was adopted. The Pt/graphite catalyst was used for five times with no significant decrease in its activity and more than 90% oxalic acid removal was obtained.
HTML PDF 收藏

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

《化学科学与工程前沿（英文）》 2011年 第5卷 第3期   页码 372-375 doi: 10.1007/s11705-010-0570-1

摘要： Calcium carbide was successfully synthesized by carbothermal reduction of lime with coke at 1973 K for 1.5 h. The effect of potassium carbonate as additive on the composition and morphology of the product was investigated using X-ray diffraction and scanning electron microscope. Addition of potassium carbonate increased the yield of calcium carbide. The sample in the presence of potassium carbonate generated acetylene gas of 168.3 L/kg, which was 10% higher than that in the absence of potassium carbonate. This result confirmed the catalytic effect of potassium carbonate on the synthesis of calcium carbide. A possible mechanism of the above effects was that the additive, which was melted at the reduction temperature, dissolved CaO and so promoted the contact between CaO and carbon, which was essential for the solid-solid reaction to form calcium carbide.

关键词： calcium carbide     synthesis     catalysis    

HTML PDF 收藏

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

《化学科学与工程前沿（英文）》 2012年 第6卷 第4期   页码 410-414 doi: 10.1007/s11705-012-1213-5

摘要： The syntheses of dimethyl oxalate (DMO) and diethyl oxalate (DEO) by CO coupling reaction in gaseous phase were investigated in a fixed bed reactor over Pd-Fe/Al O catalyst. The catalytic performance was characterized by CO conversion, space-time yield (STY) and selectivity of DMO (or DEO). The results showed that over Pd-Fe/Al O catalyst, the STY of DMO was higher than that of DEO under the same reaction conditions. The optimum reaction temperatures for synthesizing DMO and DEO were 403 K and 393 K, respectively, at the molar ratio 1 ∶ 1 of alkyl nitrite to CO. The difference in synthesizing DMO and DEO on the same catalyst was attributed to the decomposition performances of methyl nitrite (MN) and ethyl nitrite (EN), as density functional theory (DFT) calculation showed that EN decomposed more easily than MN.

关键词： palladium     CO coupling     dialkyl oxalate     alkyl nitrite     decomposition    

HTML PDF 收藏

The catalytic effect of both oxygen-bearing functional group and ash in carbonaceous catalyst on CH 4

Weidong ZHANG, Yongfa ZHANG,

《化学科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 147-152 doi: 10.1007/s11705-009-0242-1

摘要： A kind of new catalyst—carbonaceous catalyst—for CH-CO reformation has been developed in our laboratory. The effect of both oxygen-bearing functional group such as phenolic hydroxyl, carbonyl, carboxyl, and lactonic, and ash such as FeO, NaCO, and KCO in the carbonaceous catalyst on the CH-CO reforming has been investigated with a fixed-bed reactor. It has been found that the carbonaceous catalyst is an efficient catalyst on CO-CH reforming. With the decrease of oxygen-bearing functional group, the catalytic activity of carbonaceous catalyst decreases quickly. The oxygen-bearing functional groups play a significant role in the carbonaceous-catalyzed CO-CH reforming; the ash components in carbonaceous catalyst also have an important influence on the CO-CH reforming. FeO, NaCO, and KCO in the ash can catalyze the CO-CH reforming reaction; CaO has little effect on CO-CH reforming reaction. CaO can catalyze the gasification between carbonaceous catalyst and CO; AlO and MgO inhibit the CO-CH reforming.

关键词： oxygen-bearing functional     carboxyl     phenolic hydroxyl     CH-CO reformation     CO-CH reforming    

HTML PDF 收藏

Effect of hierarchical ZSM-5 zeolite crystal size on diffusion and catalytic performance of n-heptane

Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 780-789 doi: 10.1007/s11705-018-1733-8

摘要： Hierarchical ZSM-5 zeolite aggregates with different sizes of nanocrystals were synthesized using different amounts of the mesoporogen 3-aminopropyltriethoxysilane. The effect of the crystal size on the catalytic cracking of -heptane was investigated and the Thiele modulus and effectiveness factor were used to determine the reaction rate-limiting step. The crystal size affected the textual properties of the catalysts but not the acidic properties of the catalysts. The reaction rate was first order with respect to the -heptane concentration. Cracking over hierarchical zeolites with nanocrystal sizes larger than about 50 nm took place under transition-limiting conditions, whereas the reaction over hierarchical zeolites with nanocrystal sizes of 15 or 30 nm proceeded under reaction control conditions. Hierarchical ZSM-5 zeolite aggregates with smaller nanocrystals had better selectivity for light olefins which can be ascribed to the shorter diffusion path lengths and lower diffusion resistance in these catalysts. Furthermore, these catalysts had lower coking levels which can be attributed to the substantial number of mesopores which prevent the formation of coke precursors.

关键词： hierarchical ZSM-5     crystal size     catalytic cracking     Thiele modulus     effectiveness factor    

HTML PDF 收藏

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N     N-Dimethylformamide     Selective catalytic oxidation     Cu-ZSM-5     CuO particle size    

HTML PDF 收藏

The effect of doping and steam treatment on the catalytic activities of nano-scale H-ZSM-5 in the methanol

Baodong Song, Yongqiang Li, Gang Cao, Zhenhai Sun, Xu Han

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 564-574 doi: 10.1007/s11705-017-1654-y

摘要： In the transformation of methanol to gasoline (MTG), the selectivity to gasoline and the aromatic content in the produced gasoline are important factors. The catalytic activities of steam-treated and non-steam-treated nano-scale H-ZSM-5 (NHZ5) catalysts impregnated with Ag(I), Zn(II) or P(V) have been investigated in a continuous flow fixed bed reactor. The NH -TPD results showed that after impregnation, the Ag/NHZ5, Zn/NHZ5 and P/NHZ5 catalysts contained comparatively more strong, medium-strong and weak acid sites, respectively. Treatment with steam decreased the number of acid sites in all the catalysts, but the pore volumes in the catalysts were larger which improved carbon deposition resistance resulting in prolonged lifetimes. After 6 h of MTG reaction, the selectivity to gasoline for the steam-treated catalysts, , and were 70.5, 68.4 and 68.7 wt-%, respectively, whereas their respective aromatic contents in the produced gasoline were 61.9, 55.4 and 39.0 wt-%. Thus is the most promising catalyst for MTG applications which can meet the China IV gasoline standard that the amount of aromatics in gasoline should be less than 48 wt-%.

关键词： MTG     nano-scale H-ZSM-5     steam treatment     gasoline     selectivity to gasoline    

HTML PDF 收藏

Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

《化学科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 142-146 doi: 10.1007/s11705-009-0233-2

摘要： TiO-AlOmixed oxides with different compositions ranging from 40wt-% to 95wt-% of TiO were prepared by sol-gel method and impregnated with different amounts of VO. Supports and catalysts were characterized by X-ray diffraction (XRD), physisorption, temperature preprogrammed reduction (H-TPR), and ammonia temperature programmed desorption (NH-TPD). TiO content in the support had obvious effect on the crystal structure, texture characteristic, acid property, and catalytic activity in dehydrogenation of ethylbenzene (EB) with carbon dioxide. The highest catalytic activity was acquired when the TiO content was 50 wt-%.

关键词： desorption     different     TiO-AlOmixed     physisorption     ethylbenzene    

HTML PDF 收藏

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1369-z

摘要：

• Pt/CZL exhibits the optimum catalytic performance for HC and NOx elimination.

关键词： Precious metal-loaded (Ce     Zr     La)O2 catalysts     Oxygen mobility     Catalytic performance    

HTML PDF 收藏

Effect of sodium ions in synthesis of titanium silicalite-1 on its catalytic performance for cyclohexanone

Pengxu YAO,Yaquan WANG,Teng ZHANG,Shuhai WANG,Xiaoxue WU

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 149-155 doi: 10.1007/s11705-014-1409-y

摘要： Titanium silicalite-1 (TS-1) has been hydrothermally synthesized with tetrapropylammonium hydroxide (TPAOH) as the template in the presence of various amounts of Na , characterized by inductively coupled plasma, X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and ultro-violet-visible spectroscopy and studied in cyclohexanone ammoximation. The characterization results show that with the increase of Na concentration in the synthesis, both the crystal sizes of TS-1and extra framework Ti increase but framework Ti decreases. The addition of Na below 3 mol-% of TPAOH in the synthesis does not influence the catalytic properties with above 98% conversion of cyclohexanone and 99.5% selectivity to cyclohexanone oxime. However, at the concentrations of Na ≥3 mol-% of TPAOH in the synthesis, the catalysts are deactivated faster with the increase of Na addition, which can be attributed to more high molecular weight byproducts deposited in the large TS-1 particles and the loss of the frame-work titanium. The results of this work are of great importance for the industry.

关键词： extra framework Ti     cyclohexanone ammoximation     titanium silicalite-1     sodium ion     crystal size    

HTML PDF 收藏

Experimental and theoretical study of microwave enhanced catalytic hydrodesulfurization of thiophene

Hui Shang, Pengfei Ye, Yude Yue, Tianye Wang, Wenhui Zhang, Sainab Omar, Jiawei Wang

《化学科学与工程前沿（英文）》 2019年 第13卷 第4期   页码 744-758 doi: 10.1007/s11705-019-1839-7

摘要： Hydrodesulfurization (HDS) of thiophene, as a gasoline model oil, over an industrial Ni-Mo/Al O catalyst was investigated in a continuous system under microwave irradiation. The HDS efficiency was much higher (5%‒14%) under microwave irradiation than conventional heating. It was proved that the reaction was enhanced by both microwave thermal and non-thermal effects. Microwave selective heating caused hot spots inside the catalyst, thus improved the reaction rate. From the analysis of the non-thermal effect, the molecular collisions were significantly increased under microwave irradiation. However, instead of being reduced, the apparent activation energy increased. This may be due to the microwave treatment hindering the adsorption though upright S-bind (η ) and enhancing the parallel adsorption (η ), both adsorptions were considered to favor to the direct desulfurization route and the hydrogenation route respectively. Therefore, the HDS process was considered to proceed along the hydrogenation route under microwave irradiation.

关键词： thiophene     microwave irradiation     hydrodesulfurization     non-thermal microwave effect    

HTML PDF 收藏

标题 作者 时间 类型 操作

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

期刊论文

Effect of K and Ca on catalytic activity of Mn-CeO

Boxiong SHEN, Lidan DENG, Jianhong CHEN

期刊论文

Promoting effect of Zr on the catalytic combustion of methane over Pd/γ-Al

Hongbo NA,Tianle ZHU,Zhiming LIU,Yifei SUN

期刊论文

Hydrogen production by catalytic gasification of cellulose in supercritical water

GUAN Yu, PEI Aixia, GUO Liejin

期刊论文

Effect of preparation parameters on catalytic properties of Pt/graphite

LIU Zhengqian, MA Jun, ZHAO Lei

期刊论文

Effect of potassium carbonate on catalytic synthesis of calcium carbide at moderate temperature

Dejun SHI, Ke QIAO, Zifeng YAN

期刊论文

Effect of alkyl nitrite decomposition on catalytic performance of CO coupling reaction over supported

Zhenhua LI, Weihan WANG, Dongxue YIN, Jing LV, Xinbin MA

期刊论文

The catalytic effect of both oxygen-bearing functional group and ash in carbonaceous catalyst on CH 4

Weidong ZHANG, Yongfa ZHANG,

期刊论文

Effect of hierarchical ZSM-5 zeolite crystal size on diffusion and catalytic performance of n-heptane

Shuman Xu, Xiaoxiao Zhang, Dangguo Cheng, Fengqiu Chen, Xiaohong Ren

期刊论文

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

期刊论文

The effect of doping and steam treatment on the catalytic activities of nano-scale H-ZSM-5 in the methanol

Baodong Song, Yongqiang Li, Gang Cao, Zhenhai Sun, Xu Han

期刊论文

Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

期刊论文

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

期刊论文

Effect of sodium ions in synthesis of titanium silicalite-1 on its catalytic performance for cyclohexanone

Pengxu YAO,Yaquan WANG,Teng ZHANG,Shuhai WANG,Xiaoxue WU

期刊论文

Experimental and theoretical study of microwave enhanced catalytic hydrodesulfurization of thiophene

Hui Shang, Pengfei Ye, Yude Yue, Tianye Wang, Wenhui Zhang, Sainab Omar, Jiawei Wang

期刊论文