Article
Chemistry, Physical
Joachim D. Bjerregaard, Martin Votsmeier, Henrik Groenbeck
Summary: Density Functional Theory (DFT) calculations were used to investigate the low temperature deactivation of Cu-CHA by SO2 in ammonia assisted selective catalytic reduction of NO (NH3-SCR). The adsorption of SO2 on [CuII2(NH3)4O2]2+ forms a copper sulfate complex. NO and NH3 react on the sulfate complex to form N2, H2O, and H2SO4. H2SO4 undergoes an acid-base reaction with NH3, resulting in the formation of SO4(NH4)2 and HSO4(NH4), with HSO4(NH4) being thermodynamically preferred. The key mechanism for low temperature SO2 deactivation is attributed to physical effects, and the catalyst can be regenerated by exposure to high temperatures.
JOURNAL OF CATALYSIS
(2023)
Article
Engineering, Chemical
Kaiwen Ni, Yuewang Peng, Geyu Dai, Huawang Zhao, Zhiwei Huang, Xiaomin Wu, Guohua Jing, Wei Feng, Ye Yuan
Summary: In this study, ceria was used to decorate a catalyst to enhance the decomposition of ammonia bisulfate in low-temperature NH3-selective catalytic reduction. The optimal catalyst showed accelerated ABS decomposition and superior SO2 tolerance at 250 degrees Celsius. The additive CeO2 improved the catalyst's specific surface area and acidity, favoring the catalytic activity.
JOURNAL OF THE TAIWAN INSTITUTE OF CHEMICAL ENGINEERS
(2022)
Article
Multidisciplinary Sciences
Kunling Jiao, Xiangyang Chen, Xuan Bie, Daokuan Liu, Mingjie Qiu, Shuangchen Ma
Summary: The by-product of ammonium bisulfate (ABS) in flue gas has negative impacts on equipment, while wide-load denitrification and ultra-low emissions require higher NOx removal efficiency. Increasing ammonia injection can improve NOx removal, but excessive injection leads to ABS formation and deposition risks, creating a challenge for balancing between the two aspects. Industry urgently needs to address the issues of NOx control and reducing ABS impact on equipment.
SCIENTIFIC REPORTS
(2021)
Review
Chemistry, Physical
Kai Guo, Jiawei Ji, Wang Song, Jingfang Sun, Changjin Tang, Lin Dong
Summary: This review focuses on recent progress in controlling ABS deposition/decomposition during the NH3-SCR process for sustainable denitration. It covers the physicochemical properties of ABS, common methods for analyzing ABS on catalyst surfaces, strategies for restraining ABS formation and accelerating ABS decomposition, as well as suggestions for future research on ABS poisoning. The review aims to provide guidance for designing NH3-SCR catalysts with high tolerance to ABS poisoning.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Physical
Shuangye Li, Liyun Song, Jian Li, Hong He
Summary: A series of NdV/Ti-x% catalysts were prepared by a microwave-assisted deposition-precipitation method and their catalytic performance for the selective catalytic reduction (SCR) of NO by NH3 was investigated. The amount of vanadate added significantly influenced the SCR activity of the catalyst. The NdV/Ti-x% catalysts demonstrated good low-temperature catalyst activities and excellent SO2 resistance performances.
Article
Chemistry, Applied
Shuang Liu, Pan Yao, Qingjin Lin, Shuhao Xu, Mingming Pei, Jianli Wang, Haidi Xu, Yaoqiang Chen
Summary: WO3 and MoO3 are often used as acidic promoters to improve the NH3-SCR performance of composite oxide catalysts, but recent research showed significant differences in their effects on CeZrOx, with WO3/CeZrOx exhibiting wider operating temperature window and higher NOx removal efficiency compared to MoO3/CeZrOx.
Article
Chemistry, Analytical
Se Hun Lee, Jae Hoon Bang, Jichang Kim, Changyong Park, Myung Sik Choi, Ali Mirzaei, Seung Soon Im, Heejoon Ahn, Hyoun Woo Kim
Summary: For the first time, PEDOT:PSS-AVNF composite materials were successfully synthesized using a sono-chemical method for NH3 gas sensing, demonstrating higher sensitivity and shorter response time. Improved NH3 sensitivity was mainly attributed to enhanced electrical conductivity, high surface area, and p-p heterojunctions formed between PEDOT:PSS and AVNF.
SENSORS AND ACTUATORS B-CHEMICAL
(2021)
Article
Engineering, Environmental
Zhiming Gao, Josh Pihl, Tim LaClair, Brian Fricke
Summary: A comprehensive SCR model has been developed to simulate global kinetic reactions in the catalyst, showing accurate emissions estimations for both steady-state and transient conditions. The model validation against experimental data indicates its potential for assisting with SCR catalyst design optimization and emissions control technologies.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Physical
Ziyi Chen, Xiaomin Wu, Kaiwen Ni, Huazhen Shen, Zhiwei Huang, Zuoming Zhou, Guohua Jing
Summary: The surface engineering of V2O5-WO3/TiO2 by MoO3 enhanced the acid and redox cycling of NH3-SCR, leading to improved performance. The submonolayer 7Mo-VW/Ti catalyst contained more active dimeric and polymeric vanadia species, which reacted more readily with NH3, forming additional acid sites.
CATALYSIS SCIENCE & TECHNOLOGY
(2021)
Article
Engineering, Environmental
Dong Wook Kwon, Jeongeun Choi, Ki Bok Nam, Heon Phil Ha
Summary: The addition of Mo and/or Sb to a VTi catalyst improved its activity and durability in the SCR of nitrogen oxide by NH3. The addition of an appropriate amount of Mo-Sb enhanced the catalyst specific surface area, number of Bronsted acid sites, and surface species composition, thus improving catalytic activity. The presence of V2MoO8 played a key role in improving SCR performance and water/sulfur durability of the catalysts.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Jawaher Mosrati, Hanan Atia, Reinhard Eckelt, Thanh Huyen Vuong, Jabor Rabeah, Mourad Mhamdi, Udo Armbruster
Summary: NOx reduction using NH3-SCR technology is an efficient method for reducing nitrogen oxide emissions, and the Mo5/Ce40/Ti100 (SG) catalyst supported on ceria-titania shows excellent performance at low temperatures, achieving high NOx conversion rates and N-2 selectivity.
JOURNAL OF CATALYSIS
(2021)
Article
Energy & Fuels
Mengxia Qing, Siyuan Lei, Fanhai Kong, Liang Liu, Wei Zhang, Lele Wang, Tingting Guo, Sheng Su, Song Hu, Yi Wang, Jun Xiang
Summary: The generation and deposition of ammonium bisulfate in flue gas can cause serious blockage and corrosion to the air preheater, which poses a significant threat to the safe and economic operation of coal-fired power plants. Experimental results show that the generation and deposition of ammonium bisulfate/ammonium sulfate are influenced by the concentration of SO3 and NH3, the ratio of SO3 to NH3, and the deposition temperature.
Article
Chemistry, Multidisciplinary
Sooraj Mohan, P. Dinesha
Summary: In this experimental study, the thermal dissociation of ammonium carbonate is investigated using nonisothermal thermogravimetric analysis. The study provides insights into the thermal decomposition characteristics and reaction kinetics of ammonium carbonate.
Article
Chemistry, Physical
Keon Ha Hwang, Namjun Park, Hwangho Lee, Kyung-Min Lee, Se Won Jeon, Hyun Sub Kim, Yongkyu Lee, Tae Jin Kim, Won Bo Lee, Do Heui Kim
Summary: This paper reports a novel attempt to mechanistically localize vanadia on the surface of WO3-TiO2 by physically grinding high-vanadia-loading V2O5/WO3-TiO2 with WO3-TiO2. The localized vanadia catalysts exhibited enhanced activity for low-temperature NH3-SCR by forming polymeric structures. The mechanochemical interactions between clustered vanadia and titania resulted in the formation of adjacent TiO2 sites without deforming the polymeric structure of the vanadia, leading to superior sulfur resistance and less deactivation.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2023)
Article
Engineering, Chemical
Jian Wu, Zhanhong Yang, Hongzhe Chen
Summary: In this study, a one-step hydrothermal method was used to construct HNaV6O16·4H2O@reduced graphene oxide (O-d-HNaVO@rGO) electrode with oxygen-rich defects and large Zn2+ deintercalation channels. The zinc storage mechanism of the Od-HNaVO@rGO electrode was revealed through ex situ XRD and XPS techniques, showing reversible generation of by-product Zn-3(OH)(2)V2O7·2H(2)O. The Od-HNaVO@rGO battery exhibited excellent cyclic stability, high discharge capacity at high rates, and high power and energy densities, highlighting its potential as an efficient electrode cathode material.
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
(2022)
Article
Chemistry, Physical
Ming-Yi Chen, Ngoc Thanh Thuy Tran, Ahmed Abubakar Alao, Wen-Dung Hsu
Summary: This study demonstrates the significance of surface Pt atom arrangement for the efficiency of ORR in PEMFCs and reveals the correlation between Pt-Pt average distance and O2 dissociation barrier. Furthermore, the study discovers a robust correlation between the level of the catalyst's d-band center and O2 adsorption energy. High-entropy alloy substrates provide potential for controlling Pt arrangement and O2 dissociation barrier.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Eduardo C. Atayde Jr, Babasaheb M. Matsagar, Yu-Cheng Wang, Kevin C. -W. Wu
Summary: This study presents the first application of an acidic MOF, Sulfated MOF-808, in catalyzing the HAA reactions of furan oligomers for the production of biofuel precursors. The catalyst showed high yield, selectivity, and recyclability, making it versatile for different starting materials.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Maria do Carmo Rangel, Francieli Martins Mayer, Soraia Jesus de Oliveira, Sergio Gustavo Marchetti, Fabricio Luiz Faita, Doris Ruiz, Giovanni Saboia, Mariana Kieling Dagostini, Jonder Morais, Maria do Carmo Martins Alves
Summary: This study developed a new catalyst by investigating the effect of magnesium on the catalytic properties of hematite in ethylbenzene dehydrogenation. The catalyst showed important differences in activity, selectivity, and stability, making it a promising candidate for commercial applications.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yanjun Li, Qian Wang, Hui Tian, Mingyuan Zhu, Yuanyuan Liu
Summary: A novel strategy using microwave-assisted precipitation was proposed to prepare defective CsH3PMo11VO40 catalyst for the oxidation of methacrolein to methacrylic acid. Microwave treatment accelerates crystallization, increases vanadyl species content, and forms defective Keggin structures, thereby enhancing the oxidation capacity of the catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Rajeshwari Athavale, Sailee Gardi, Fatima Choudhary, Dayanand Patil, Nandkishor Chandan, Paresh More
Summary: In this study, a novel acidic ionic liquid catalyst was prepared and used for the synthesis of bis-indolyl methane derivatives. The catalyst exhibited short reaction times, easy purification, and reusability.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Masatomo Hattori, Takato Hattori, Masakuni Ozawa
Summary: Cu-added gamma-Al2O3 catalysts were prepared with varying Cu loadings and the effects of copper oxidation states on catalytic activity were investigated. The results showed that the addition of copper increased the catalyst activity, but excessive copper loading decreased catalytic activity. XRD and TEM analysis indicated the formation of a solid solution of copper oxide species on the surface of gamma-Al2O3. XAS and TPR data demonstrated variations in copper oxidation states among the catalysts.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liwei Fang, Shiyang Niu, Shengsen Wang, Yiqing Lu, Yuanhui Cheng
Summary: In this study, PtNi alloy on nitrogen-doped carbon and SnO2 dual-support was designed to modulate the metal-support interaction, resulting in improved catalytic activity and stability for oxygen reduction reaction. The SnO2/PtNi/NC catalyst exhibited a strongly coupled interface, enhanced electron transfer, and higher half-wave potential compared to PtNi/NC and commercial Pt/C.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Shohei Harada, Duanxing Li, Kenta Iyoki, Masaru Ogura
Summary: This study investigates the catalytic performance of a composite catalyst composed of ZnZrOX and H-zeolite for the hydrogenation of CO2. The deactivation of the composite catalyst is influenced by ion exchange of Zn2+ and/or coke, with their effects differing based on the zeolite structure. Separating the grains of the composite catalyst can prevent deactivation.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Laura Proano, Christopher W. Jones
Summary: In this study, NiGa alloy particles supported on CeO2, ZrO2, and ZrO2-CeO2 solid solutions were prepared and characterized. The nature of the support was found to have a significant influence on the catalyst's activity and selectivity, with the crystalline structure of ZrO2 having the greatest impact. Pure ZrO2 showed the highest methanol selectivity and CO2 conversion at high Zr:Ce ratios. In equimolar and Ce-rich conditions, basic sites and oxygen vacancies were found to be the key parameters affecting methanol production.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Liyan Zhang, Yinze Yang, Leilei Zhou, Fengyu Zhao, Haiyang Cheng
Summary: 1,6-Hexamethylenediamine was successfully synthesized via the reductive amination of 1,6-hexanediol using a Ru/PRL(x)-Al2O3 catalyst. The highly dispersed and anchored Ru species, formed by 1,10-phenanthroline (PRL), played a crucial role in the catalytic reaction. The formation of new acid-base pairs, electron deficient Ru species, and smaller nanoparticles contributed to the improved catalytic performances of the Ru/PRL-Al2O3 catalyst.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Anita Horvath, Miklos Nemeth, Andrea Beck, Gyorgy Safran, Valeria La Parola, Leonarda Francesca Liotta, Gregor Zerjav, Matevz Roskaric, Albin Pintar
Summary: This study investigates the catalytic and structural changes caused by the addition of 0.25 wt% indium in a 3% Ni/CeO2-Al2O3 catalyst prepared by impregnation method. The results show that the addition of indium can decrease the activity of the catalyst, but it improves its stability and reduces coking.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Ankush Kularkar, Vaibhav Vilas Khedekar, Sachin D. Chaudhari, Mudavath Ravi, Sadhana S. Rayalu, Penumaka Nagababu
Summary: Efficiently addressing the challenges of photocatalytic CO2 reduction to CH3OH is crucial. This study developed Zn-BTC MOF and its composites with CaIn2S4, achieving highly efficient and robust photocatalytic CO2 reduction to CH3OH under ambient conditions, using H2O2 as the hydrogen source. Among the composites, ZMCIS4 demonstrated excellent performance with a CH3OH evolution of 49100 μmol/g.cat and a quantum efficiency of approximately 78.41%. The enhanced performance was attributed to the production of nascent hydrogen atoms (H center dot) through the photo-splitting of H2O2 on the ZMCIS surface.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Dan Liu, Yudong Li, Chengyu Wang, Haiyue Yang, Rong Wang, Shujun Li, Xiaohui Yang
Summary: In this study, a self-supporting three-dimensional porous Co3O4 nanobelt array decorated on nickel foam (P-Co3O4 -NBA@NF) electrode with numerous active sites was successfully constructed for the oxidation of 5-Hydroxymethylfurfural (HMF) to 2,5-furan dicarboxylic acid (FDCA). The P-Co3O4 -NBA@NF electrode demonstrated high conversion efficiency, selectivity, and Faraday efficiency, as well as remarkable long-term stability. This research provides a promising electrocatalyst for biomass conversion.
APPLIED CATALYSIS A-GENERAL
(2024)
Article
Chemistry, Physical
Yimin Li, Enggah Kurniawan, Fumiya Sato, Takayoshi Hara, Yasuhiro Yamada, Satoshi Sato
Summary: In this study, several silica-alumina catalysts modified with Ag were examined for the dehydration of 1,3-butanediol to 1,3-butadiene. Among them, an amorphous silica-alumina catalyst (SAL-3) modified with Ag showed the highest improvement in catalytic activity and stability when operated in H2 flow. The generation of reversible acid sites was found to be the reason behind the enhanced activity and stability of this Ag/SAL-3 catalyst. The effects of various parameters on the catalytic activity of Ag/SAL-3, such as reaction temperature, contact time, Ag content, and carrier gas, were investigated.
APPLIED CATALYSIS A-GENERAL
(2024)