Article
Chemistry, Physical
Huawang Zhao, Xiaoyin Chen, Adarsh Bhat, Yongdan Li, Johannes W. Schwank
Summary: The Si/Al ratio has a significant impact on the deactivation process of Pd/SSZ-13 samples, with samples with a lower Si/Al ratio experiencing more severe structural damage during aging. Agglomeration of Pd2+ ions on the zeolite surface leads to deactivation, while the mobility of Pd cations is also a key factor in the decline of NO adsorption capacity.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Physical
Dan Li, Guoju Yang, Mengyang Chen, Lei Pang, Yanbing Guo, Jihong Yu, Tao Li
Summary: This study synthesized a Pd catalyst based on Na-SSZ-13 and investigated the effect of Na co-cations on its low-temperature NO adsorption. The results showed that Na co-cations can improve the stability and activity of the catalyst, and help mitigate dealumination during hydrothermal aging.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2022)
Article
Engineering, Environmental
Dawei Yao, Phuoc Hoang Ho, Rojin Feizie Ilmasani, Johann C. Wurzenberger, Thomas Glatz, Derek Creaser, Louise Olsson
Summary: In this study, a novel form of Pd/SSZ-13 was developed by freeze-drying method, which showed better stability compared to the sample synthesized by the common process. Characterization measurements revealed that the Pd sites on the freeze-dried sample had stronger resistance to CO-induced agglomeration. In-situ characterization and kinetic modeling demonstrated that the freeze-dried Pd/SSZ-13 had more ion-exchanged Pd sites, providing greater resistance towards CO-induced Ostwald ripening process and suppressing the sintering behavior under high CO concentration.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Mugdha Ambast, Abhay Gupta, Bhuiyan Md Mushfikur Rahman, Lars C. Grabow, Michael P. Harold
Summary: A transient monolith model is proposed to study NO uptake and release over Pd/SSZ-13, with or without reductants CO or C2H4. Kinetic parameters are estimated using a combination of DFT and experimental data fitting, which helps interpret data features and optimize operating conditions. The model shows higher NO uptake on Pd/SSZ-13 compared to Pd/ZSM-5.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Physical
Pranaw Kunal, Todd J. Toops, Michelle K. Kidder, Michael J. Lance
Summary: Pd-functionalized chabazite (Pd/SSZ-13) demonstrated varying levels of effectiveness in passive NOx adsorption (PNA) under different experimental conditions, with notable differences observed in the presence of CO and unsaturated hydrocarbons. The desorption behaviors also showed qualitative differences, with distinct desorption stages observed for different feed conditions. The presence of CO and unsaturated hydrocarbons in the feed resulted in almost complete elimination of lower temperature desorption peaks.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Engineering, Environmental
Huawang Zhao, Xiaoyin Chen, Alexander J. Hill, Guohua Jing, Yongdan Li, Johannes W. Schwank
Summary: Pd/SSZ-13 catalysts were investigated for the simultaneous storage of NO and C3H6 at 100 degrees C. The effects of the state of Pd species on co-adsorption and release were studied under simulated exhaust conditions. The results showed that the NO storage capacity at 100 degrees C was enhanced by simultaneous NO + C3H6 adsorption. DRIFTs results showed that Pd2+ provides the adsorption sites for NO + C3H6 to form Pd2+(NO) (C3H6), which alleviates the inhibition effect of H2O on NO adsorption on Pd ions. The different release behaviors of NO + C3H6 are discussed based on the chemistry of NO and C3H6 adsorption and the effect of intermediate CO.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Chemistry, Physical
Huawang Zhao, Xiaoyin Chen, Adarsh Bhat, Yongdan Li, Johannes W. Schwank
Summary: The chemistry of preparing Pd/SSZ-13 was studied, focusing on the effect of NH4-SSZ-13 support on Pd2+ ion dispersion. The Pd(NO3)(2) precursor transformed into Pd(NH3)(x)(2+) during calcination, and then converted into Pd2+ ions occupying ion-exchange sites. The formation of Pd(NH3)(x)(2+) intermediates played a critical role in achieving high Pd2+ dispersion.
APPLIED CATALYSIS B-ENVIRONMENTAL
(2021)
Article
Chemistry, Applied
Jaeha Lee, Yongwoo Kim, Sungha Hwang, Eunwon Lee, Hyokyoung Lee, Chang Hwan Kim, Do Heui Kim
Summary: Pd/SSZ-13 exhibits better NO adsorption ability at low temperature, while Pd/ZSM-5 undergoes sintering and deactivation when co-adsorbing NO and H2O. Therefore, Pd/SSZ-13 is a superior candidate for NO storage material to reduce NOx emissions from vehicle exhaust.
Article
Engineering, Environmental
Jinhuang Cai, Yating Huang, Xiaomin Wu, Zhiwei Huang, Huazhen Shen, Kai Cui, Zhenguo Li, Guohua Jing, Johannes W. Schwank, Huawang Zhao
Summary: In this study, a method to improve the hydrothermal stability of Pd/SSZ-13 was proposed, and it was demonstrated that the smart behavior of Ni2+ ions could enhance the NOx storage capacity of the material. The presence of Ni2+ ions occupied single Al sites and transformed into more thermally stable Z2Ni2+ during hydrothermal aging, effectively limiting dealumination. Compared to undoped Pd/SSZ-13, Pd/Ni/SSZ-13 showed increased NOx storage capacity and maintained good hydrothermal stability.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Environmental
Dan Li, Qianzhao Ding, Dapeng Hao, Jinfeng Han, Guoju Yang, Lei Pang, Yanbing Guo, Jihong Yu, Tao Li
Summary: This study presents a simple and efficient strategy for regenerating phosphorus-poisoned Pd/SSZ-13 with the cooperation of hydrothermal aging treatment and Na cocations. The restoration ratio of the adsorption capacity of poisoned Pd/SSZ-13 was over 90% after regeneration, and the NOx adsorption activities of the phosphorus-poisoned Pd/SSZ-13 almost completely recovered.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Dawei Yao, Rojin Feizie Ilmasani, Johann C. Wurzenberger, Thomas Glatz, Joonsoo Han, Aiyong Wang, Derek Creaser, Louise Olsson
Summary: The study illustrates a CO-assisted mechanism for passive NOx adsorption (PNA) by combining experimental and kinetic modeling studies. Pd/SSZ-13 was used as a PNA to control NOx emissions during cold start periods, with the effect of varying gas compositions evaluated. It was found that CO reduces Pd(II) species to Pd(I)/Pd(0) species, increasing the stability of stored NOx species.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Engineering, Environmental
Mugdha Ambast, Sotirios A. Malamis, Michael P. Harold
Summary: The study reports the effects of C12H26 on NO uptake and release mechanisms in a Pd/SSZ-13-coated PNA monolith. Pre-adsorbed C12H26 may block NO access to pores, decreasing available sites for NO uptake. Furthermore, oxidation of C12H26 can delay NO release by forming CO which binds strongly to Pd sites.
CHEMICAL ENGINEERING JOURNAL
(2021)
Article
Chemistry, Applied
Aiyong Wang, Kunpeng Xie, Ashok Kumar, Krishna Kamasamudram, Louise Olsson
Summary: A concept of a layered Pd/SSZ-13 with Cu/SSZ-13 as PNA-SCR dual-layer monolith catalyst for NOx abatement is demonstrated. The dual-layer sample maintains most of the NOx storage capacity while the NOx desorption temperature is modified due to Cu/SSZ-13 as the top layer. The dual-layer concept shows interesting potential for NOx abatement, but requires further developments on the PNA material to ensure stable storage capacity.
Article
Chemistry, Multidisciplinary
Jinhuang Cai, Huawang Zhao, Xiang Li, Guohua Jing, Johannes W. Schwank
Summary: Insufficient hydrothermal stability limits the application of Pd/SSZ-13 for low-temperature NO adsorption. The introduction of Mg improves the stability of Pd/SSZ-13 by reducing dealumination and preserving the structure. Mg/Pd/SSZ-13 retains Pd2+ ions and exhibits high NO storage capacity.
REACTION CHEMISTRY & ENGINEERING
(2023)
Article
Engineering, Environmental
Dan Li, Ying Meng, Dapeng Hao, Qianzhao Ding, Lei Pang, Guoju Yang, Yanbing Guo, Jihong Yu, Tao Li
Summary: This study investigated the deactivation effects of phosphorus on Pd/SSZ-13 and found that phosphorus decreased the porosity and acidity of the catalyst, resulting in the decrease of active sites and the decrease in activity and stability.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Chemistry, Physical
Eun J. Jeong, Jae H. Lee, Seong H. Lee, Chung S. Park, Jin W. Choung, Chang H. Kim, Kwan-Young Lee
Article
Chemistry, Physical
Jae Hwan Lee, Seong Ho Lee, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
APPLIED CATALYSIS B-ENVIRONMENTAL
(2019)
Article
Chemistry, Applied
Jaeha Lee, Yongwoo Kim, Sungha Hwang, Eunwon Lee, Hyokyoung Lee, Chang Hwan Kim, Do Heui Kim
Summary: Pd/SSZ-13 exhibits better NO adsorption ability at low temperature, while Pd/ZSM-5 undergoes sintering and deactivation when co-adsorbing NO and H2O. Therefore, Pd/SSZ-13 is a superior candidate for NO storage material to reduce NOx emissions from vehicle exhaust.
Article
Engineering, Environmental
Min June Kim, Geun-Ho Han, Seong Ho Lee, Hyun Wook Jung, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
JOURNAL OF HAZARDOUS MATERIALS
(2020)
Article
Chemistry, Physical
Jaeha Lee, Jonghyun Kim, Yongwoo Kim, Sungha Hwang, Hyokyoung Lee, Chang Hwan Kim, Do Heui Kim
APPLIED CATALYSIS B-ENVIRONMENTAL
(2020)
Article
Chemistry, Physical
Beom-Sik Kim, Hojin Jeong, Junemin Bae, Pyung Soon Kim, Chang Hwan Kim, Hyunjoo Lee
APPLIED CATALYSIS B-ENVIRONMENTAL
(2020)
Article
Chemistry, Physical
Hyun Jae Kim, Jae Hwan Lee, Min Woo Lee, Yaeun Seo, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
MOLECULAR CATALYSIS
(2020)
Article
Energy & Fuels
Jae Hwan Lee, Byung Jin Lee, Dae-Won Lee, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
Article
Chemistry, Applied
Sungha Hwang, Yongwoo Kim, Jaeha Lee, Eunwon Lee, Hyokyoung Lee, Changho Jeong, Chang Hwan Kim, Do Heui Kim
Summary: This study reveals that CO can enhance the NOx adsorption ability of Pd/CeO2 catalyst at low temperatures. A mechanism is proposed based on the changing CO oxidation ability with increased NOx adsorption over Pd/CeO2.
Article
Chemistry, Physical
Eun Jun Lee, Min June Kim, Jin Woo Choung, Chang Hwan Kim, Kwan-Young Lee
Summary: The Ag/2MnO(x)-1CeO(2) catalyst showed significantly improved soot oxidation and NO oxidation activity under NOx-assisted conditions, demonstrating the importance of NOx adsorption characteristics in the process.
APPLIED CATALYSIS A-GENERAL
(2021)
Article
Chemistry, Physical
Yongwoo Kim, Hwangho Lee, Seungdo Yang, Jaeha Lee, Hyungjoo Kim, Sungha Hwang, Se Won Jeon, Do Heui Kim
Summary: By rationally designing a catalyst structure, ultrafine Pd nanoparticles supported on carbon nanotubes were successfully synthesized, significantly enhancing the activity of the formic acid dehydrogenation reaction.
JOURNAL OF CATALYSIS
(2021)
Article
Chemistry, Physical
Yongwoo Kim, Jongbaek Sung, Sungsu Kang, Jaeha Lee, Min-Ho Kang, Sungha Hwang, Hayoung Park, Joodeok Kim, Younhwa Kim, Eunwon Lee, Gyeong-Su Park, Do Heui Kim, Jungwon Park
Summary: Achieving full dispersion of isolated Pd2+ ions in small-pore SSZ-13 zeolite and generating uniformly dispersed nano-sized PdO clusters result in enhanced catalytic performances towards a passive NOx adsorber and CH4 combustion through controlled ion-exchange and rationalized thermal treatment.
JOURNAL OF MATERIALS CHEMISTRY A
(2021)
Article
Engineering, Environmental
Yongwoo Kim, Sungha Hwang, Jaeha Lee, YoungSeok Ryou, Hyokyoung Lee, Chang Hwan Kim, Do Heui Kim
EMISSION CONTROL SCIENCE AND TECHNOLOGY
(2019)
Article
Chemistry, Physical
Jaeha Lee, YoungSeok Ryou, Sungha Hwang, Yongwoo Kim, Sung June Cho, Hyokyoung Lee, Chang Hwan Kim, Do Heui Kim
CATALYSIS SCIENCE & TECHNOLOGY
(2019)
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)