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Cu(In 4

Ga)Se2 3

X射线 3

光催化 3

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CO2捕集 2

二氧化碳 2

低碳发展 2

催化剂 2

固体氧化物电解池 2

碳中和 2

高压 2

&alpha 1

(GaxIn1−x)2O3薄膜;带隙可调谐;磁控溅射 1

1 1

1T/2H-MoS2 1

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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    

Numerical simulation and experimental verification of chemical reactions for SCR DeNO

Qiang ZHANG, Yonglin FAN, Wenyan LI

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 523-528 doi: 10.1007/s11705-010-0520-y

摘要: Selective catalytic reduction (SCR) is a major commercial technology for NO removal in power plants. There are a lot of complex chemical reactions in SCR reactors, and it is of great significance to understand the internal process of chemical reactions for SCR DeNO and study the impact of various factors on NO removal efficiency. In this paper, the impact of reaction temperature, ammonia-nitrogen molar ratio and resident time in the catalyst bed layer on NO removal efficiency were studied by simulation of chemical reactions. Then calculated results were compared with catalyst activity test data in a power plant, which proved that the simulated results were accurate. As a result, the reaction conditions were optimized in order to get the best removal efficiency of NO, so that we can provide a reference for optimal running of SCR in power plants.

关键词: SCR     NOx     removal efficiency     chemical reactions     simulation    

The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 457-463 doi: 10.1007/s11783-013-0512-5

摘要: Selective catalytic reduction of NO by H in the presence of oxygen has been investigated over Pt/Al O catalysts pre-treated under different conditions. Catalyst preparation conditions exert significant influence on the catalytic performance, and the catalyst pre-treated by H or H then followed by O is much more active than that pre-treated by air. The higher surface area and the presence of metallic Pt over Pt/Al O pre-treated by H or pretreated by H then followed by O can contribute to the formation of NO , which then promotes the reaction to proceed at low temperatures.

关键词: NOx reduction     Pt/Al2O3     preparation condition     H2-SCR    

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 518-523 doi: 10.1007/s11783-012-0427-6

摘要: This study was conducted to evaluate the toxicological response of -nitrotoluene and -nitroaniline to the key fish species, . A freshwater fish bioassay based on the 96 h was used to estimate the single and joint toxicity of the two chemicals. The toxicity of -nitrotoluene was greater than that of -nitroaniline based on 96 h values of 40.74 mg·L and 48.99 mg·L , respectively. Both compounds had moderate toxicity toward , and this toxicity increased with the exposure duration and concentration. Binary mixtures of the compounds were more toxic than the individual compounds at 96 h, and they acted upon partial addition. When the exposure time was longer, the toxicity increased for mixtures of compounds with the same concentration or toxicity. The results of this study suggest that exposure to a combination of these chemicals would result in a higher environmental risk in aquatic systems than exposure to either compound alone. Further research is needed to investigate the combined effects and sublethal toxicity of -nitrotoluene and -nitroaniline, since they are both still used in China.

关键词: joint toxicity     Cyprinus carpio     LC50     p-nitrotoluene     p-nitroaniline     toxic unit    

Design and operational considerations for selective catalytic reduction technologies at coal-fired boilers

Jeremy J. SCHREIFELS, Shuxiao WANG, Jiming HAO

《能源前沿(英文)》 2012年 第6卷 第1期   页码 98-105 doi: 10.1007/s11708-012-0171-4

摘要: By the end of 2010, China had approximately 650 GW of coal-fired electric generating capacity producing almost 75% of the country’s total electricity generation. As a result of the heavy reliance on coal for electricity generation, emissions of air pollutants, such as nitrogen oxides (NO ), are increasing. To address these growing emissions, the Ministry of Environmental Protection (MEP) has introduced new NO emission control policies to encourage the installation of selective catalytic reduction (SCR) technologies on a large number of coal-fired electric power plants. There is, however, limited experience with SCR in China. It is therefore useful to explore the lessons from the use of SCR technologies in other countries. This paper provides an overview of SCR technology performance at coal-fired electric power plants demonstrating emission removal rates between 65% and 92%. It also reviews the design and operational challenges that, if not addressed, can reduce the reliability, performance, and cost-effectiveness of SCR technologies. These challenges include heterogeneous flue gas conditions, catalyst degradation, ammonia slip, sulfur trioxide (SO ) formation, and fouling and corrosion of plant equipment. As China and the rest of the world work to reduce greenhouse gas emissions, carbon dioxide (CO ) emissions from parasitic load and urea-to-ammonia conversion may also become more important. If these challenges are properly addressed, SCR can reliably and effectively remove up to 90% of NO emissions at coal-fired power plants.

关键词: nitrogen oxides (NOx)     coal     selective catalytic reduction (SCR)     air pollution control    

Experimental investigations on combustion characteristics of syngas composed of CH

Qingwei FAN, Shien HUI, Qulan ZHOU, Qinxin ZHAO, Tongmo XU

《化学科学与工程前沿(英文)》 2010年 第4卷 第4期   页码 404-410 doi: 10.1007/s11705-010-0513-x

摘要: The residual gas and remained raw gas in dual gas resources polygeneration system are quite complex in components (mainly CH , CO, and H ), and these results to the distinguished differences in combustion reaction. Experimental investigations on basic combustion characteristics of syngas referred above are conducted on a laboratory-scale combustor with flame temperature and flue gas composition measured and analyzed. Primary air coefficient (PA), total air coefficient (TA), and components of the syngas (CS) are selected as key factors, and it is found that PA dominates mostly the ignition of syngas and NO formation, while TA affects the flue gas temperature after high temperature region and NO formation trend to be positive as H /CO components increase. The results provide references for industrial utilization.

关键词: dual gas resources polygeneration     lean premixed combustion     residual gas     remained raw gas     NOx emission    

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

《能源前沿(英文)》 2013年 第7卷 第1期   页码 119-126 doi: 10.1007/s11708-012-0226-6

摘要: Micronized coal reburning (MCR) can not only reduce carbon in fly ash but also reduce NO emissions as compared to the conventional coal reburning. However, it has two major kinetic barriers in minimizing NO emission. The first is the conversion of NO into hydrogen cyanide (HCN) by conjunction with various hydrocarbon fragments. The second is the oxidation of HCN by association with oxygen-containing groups. To elucidate the advantages of MCR, a combination of Diffuse Reflection Fourier Transform Infrared (FTIR) experimental studies with Density Functional Theory (DFT) theoretical calculations is conducted in terms of the second kinetic barrier. FTIR studies based on Chinese Tiefa coal show that there are five hydroxide groups such as OH-π, OH-N, OH-OR , self-associated OH and free OH. The hydroxide groups increase as the mean particle size decreases expect for free OH. DFT calculations at the B3LYP/6-31 G(d) level indicate that HCN can be oxidized by hydroxide groups in three paths, HCN+OH→HOCN+H (path 1), HCN+OH→HNCO+H (path 2), and HCN+OH→CN+H O (path 3). The rate limiting steps for path 1, path 2 and path 3 are IM2→P1+H (170.66 kJ/mol activated energy), IM1→IM3 (231.04 kJ/mol activated energy), and R1+OH→P3+H O (97.14 kJ/mol activated energy), respectively. The present study of MCR will provide insight into its lower NO emission and guidance for further studies.

关键词: hydroxyl radicals     Fourier transform infrared spectroscopy (FTIR)     density functional theory (DFT)     homogeneous reaction mechanism     NOx    

The abatement of major pollutants in air and water by environmental catalysis

Junhua LI, Hong HE, Chun HU, Jincai ZHAO

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 302-325 doi: 10.1007/s11783-013-0511-6

摘要: This review reports the research progress in the abatement of major pollutants in air and water by environmental catalysis. For air pollution control, the selective catalytic reduction of NO (SCR) by ammonia and hydrocarbons on metal oxide and zeolite catalysts are reviewed and discussed, as is the removal of Hg from flue gas by catalysis. The oxidation of Volatile organic compounds (VOCs) by photo- and thermal- catalysis for indoor air quality improvement is reviewed. For wastewater treatment, the catalytic elimination of inorganic and organic pollutants in wastewater is presented. In addition, the mechanism for the procedure of abatement of air and water pollutants by catalysis is discussed in this review. Finally, a research orientation on environment catalysis for the treatment of air pollutants and wastewater is proposed.

关键词: air pollution control     wastewater treatment     DeNOx     selective catalytic reduction (SCR)     Volatile organic compounds (VOCs)     environmental catalysis    

Denitrification performance and sulfur resistance mechanism of Sm–Mn catalyst for low temperature NH-SCR

《化学科学与工程前沿(英文)》 2023年 第17卷 第5期   页码 617-633 doi: 10.1007/s11705-022-2258-8

摘要: MnOx and Sm–Mn catalysts were prepared with the coprecipitation method, and they showed excellent activities and sulfur resistances for the selective catalytic reduction of NOx by NH3 between 50 and 300 °C in the presence of excess oxygen. 0.10Sm–Mn catalyst indicated better catalytic activity and sulfur resistance. Additionally, the Sm doping led to multi-aspect impacts on the phases, morphology structures, gas adsorption, reactions process, and specific surface areas. Therefore, it significantly enhances the NO conversion, N2 selectivity, and sulfur resistance. Based on various experimental characterization results, the reaction mechanism of catalysts and the effect of SO2 on the reaction process about the catalysts were extensively explored. For 0.10Sm–Mn catalyst, manganese sulfate and sulfur ammonium cannot be generated broadly under the influence of SO2 and the amount of surface adsorbed oxygen. The Bronsted acid sites strengthen significantly due to the addition of SO2, enhancing the sulfur resistance of the 0.10Sm–Mn catalyst.

关键词: MnOx     Sm–Mn     catalyst     NH3-SCR     sulfur resistance    

Synthesis of

Lili ZHANG, Ming LIU, Shijun MA, Yaodong HUANG, Yongmei WANG

《化学科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 408-414 doi: 10.1007/s11705-013-1343-4

摘要: Two new -symmetric primary-secondary diamines were synthesized via the reaction of ( , )-1,2-diphenyl ethylene diamine with 3,5-ditert-butyl salicylaldehyde and salicylaldehyde, respectively, followed by reduction with NaBH . The combination of the ligand from 3,5-ditert-butyl salicylaldehyde with CuBr could effciently catalyze the Henry reaction to afford -nitroalkanols in moderate to good yields (up to 87%) and high enantioselectivities (up to 88% ). A possible mechanism of the reaction was proposed.

关键词: enantioselective Henry reaction     C1-symmetric diamines     asymmetric reaction     nitroalkanol    

Electro-catalytic activity of CeO modified graphite felt for carbamazepine degradation via E-peroxone

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1410-x

摘要:

•CeOx/GF-EP process had the better degradation efficiency than GF-EP process.

关键词: E-peroxone     CeOx     Graphite felt     Carbamazepine     Mineralization    

Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

《环境科学与工程前沿(英文)》 2012年 第6卷 第1期   页码 59-65 doi: 10.1007/s11783-010-0259-1

摘要: Sorption isotherms of galaxolide (HHCB) of different fractions from two sediments with different mineral and organic carbon contents were determined to compare HHCB sorption behavior and contribution to the total sorption. The HHCB sorption isotherms that used the batch equilibration method were studied on different sediments of different fractions. The sorption isotherms of 600°C heating fractions were detailed using the linear model, while the other fractions were nonlinear and fitted well with the Freundlich model. The dissolved organic carbon (DOC) removed, NaOH extracted, and 375°C heating fractions showed more nonlinear sorption than the original sediments, which suggested more heterogeneous sorption sites in these fractions. Compared to the original sediments, the 375°C heating fractions had higher carbon-normalized distribution coefficient ( ) values, indicating a higher sorption affinity for HHCB. Among the different sediment fractions, the contribution of the 600°C heating fractions to the overall sorption were the lowest (<20%), while the 375°C heating fractions were the highest (up to 85%).

关键词: galaxolide (HHCB)     sorption     organic carbon     sediment     carbon-normalized distribution coefficient (Koc)    

H<sub>∞sub> control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

《结构与土木工程前沿(英文)》 2013年 第7卷 第3期   页码 264-275 doi: 10.1007/s11709-013-0214-x

摘要: A floor isolation system installed in a single floor or room in a fixed base structure is designed to protect equipment. With this configuration, the input motions to the floor isolation from the ground motions are filtered by the structure, leaving the majority of the frequency content of the input motion lower than the predominant frequency of the structure. The floor isolation system should minimize the acceleration to protect equipment; however, displacement must also be limited to save floor space, especially with long period motion. Semi-active control with an control was adopted for the floor isolation system and a new input shaping filter was developed to account for the input motion characteristics and enhance the effectiveness of the control. A series of shake table tests for a semi-active floor isolation system using rolling pendulum isolators and a magnetic-rheological damper were performed to validate the control. Passive control using an oil damper was also tested for comparison. The test results show that the control effectively reduced acceleration for short period motions with frequencies close to the predominant frequency of the structure, as well as effectively reduced displacement for long period motions with frequencies close to the natural frequency of the floor isolation system. The control algorithm proved to be more advantageous than passive control because of its capacity to adjust control strategies according to the different motion frequency characteristics.

关键词: semi-active     floor isolation     H control     MR damper     shaping filter     shaking table test    

CeO doping boosted low-temperature NH-SCR activity of FeTiO catalyst: A microstructure analysis and reaction

《环境科学与工程前沿(英文)》 2022年 第16卷 第5期 doi: 10.1007/s11783-022-1539-2

摘要:

• CeO2 doping significantly improved low-temperature NH3-SCR activity on FeTiOx.

关键词: NH3-SCR     CeO2 doping     Low-temperature NOx removal     Improved redox property     In situ XAFS analysis    

Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第2期   页码 151-157 doi: 10.1007/s11783-013-0482-7

摘要: The formation of cancinogenic nitrosamines, esp. -nitrosodimethylamine (NDMA) in water and wastewater treatment plants has drawn much attention in recent years. Dissolved organic matter from the transported Luan River water as water source of Tianjin was fractionated with different XAD resins and a series of ultra-filtration membranes with molecular weight (MW) cut-offs of 5k Da, 3k Da, and 1k Da, respectively. The NDMA yields from the raw water and each fraction were measured to investigate their role in NDMA yield. Results indicated that the hydrophilic fraction had a higher NDMA yield than those of hydrophobic fraction and transphilic fraction. The fraction with MW below 1k Da had a higher NDMA yield than that with larger MW. NDMA formation increased as the dissolved organic carbon (DOC) to dissolved organic nitrogen (DON) ratio decreased, which indicated that DON might serve as the real important precursor for NDMA. The correlation between NDMA yield and specific ultraviolet absorbance at 254 nm (SUVA ) suggested that the latter might not represent the specific precursors for NDMA in the water. Besides the water quality, the influences of pH, disinfectant dosage, and disinfection contact time on the formation of NDMA were also examined. These results will help water treatment plants establish measures to control this harmful disinfection by-product.

关键词: N-nitrosodimethylamine (NDMA)     disinfection by-product     dissolved organic nitrogen (DOC)     hydrophilic     molecular weight (MW)     specific ultraviolet absorbance at 254 nm (SUVA254)    

标题 作者 时间 类型 操作

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

Boxiong SHEN, Lidan DENG, Jianhong CHEN

期刊论文

Numerical simulation and experimental verification of chemical reactions for SCR DeNO

Qiang ZHANG, Yonglin FAN, Wenyan LI

期刊论文

The effect of preparation conditions of Pt/Al

Lei YUAN, Xiang ZHENG, Kaijiao DUAN, Hao HU, Jinggang WANG, Seong Ihl WOO, Zhiming LIU

期刊论文

Assessment of toxicity of two nitroaromatic compounds in the freshwater fish

Hongyan SHEN, Jixi GAO, Jinsheng WANG

期刊论文

Design and operational considerations for selective catalytic reduction technologies at coal-fired boilers

Jeremy J. SCHREIFELS, Shuxiao WANG, Jiming HAO

期刊论文

Experimental investigations on combustion characteristics of syngas composed of CH

Qingwei FAN, Shien HUI, Qulan ZHOU, Qinxin ZHAO, Tongmo XU

期刊论文

A combined experimental and theoretical study of micronized coal reburning

Hai ZHANG, Jiaxun LIU, Jun SHEN, Xiumin JIANG

期刊论文

The abatement of major pollutants in air and water by environmental catalysis

Junhua LI, Hong HE, Chun HU, Jincai ZHAO

期刊论文

Denitrification performance and sulfur resistance mechanism of Sm–Mn catalyst for low temperature NH-SCR

期刊论文

Synthesis of

Lili ZHANG, Ming LIU, Shijun MA, Yaodong HUANG, Yongmei WANG

期刊论文

Electro-catalytic activity of CeO modified graphite felt for carbamazepine degradation via E-peroxone

期刊论文

Effects of different sediment fractions on sorption of galaxolide

Lixia JIN, Mengchang HE, Jinghuan ZHANG

期刊论文

H<sub>∞sub> control in the frequency domain for a semi-active floor isolation system

Yundong SHI, Tracy C BECKER, Masahiro KURATA, Masayoshi NAKASHIMA

期刊论文

CeO doping boosted low-temperature NH-SCR activity of FeTiO catalyst: A microstructure analysis and reaction

期刊论文

Factors controlling

Chengkun WANG, Xiaojian ZHANG, Chao CHEN, Jun WANG

期刊论文