MIISTRY OF EDUCATION AND TRAINING HANOI UNIVERSITY OF SCIENCE AND TECHNOLOG Y PHẠM THỊ MAI PHƢƠNG STUDY ON THE PROCEDURES OF THE SUPPORT ON THE SUBSTRATES TO PREPARE CATALYTIC COMPLEXES FOR THE TREATMENT OF MOTORBIKE’S EXHAUSTED GASES DOCTOR OF PHILOSOPHY THESIS: CHEMICAL ENGINEERING HANOI – 2014 1 e MINISTRY OF EDUCATION AND TRAINING HANOI UNIVERSITY OF SCIENCE AND TECHNOLOGY PHẠM THỊ MAI PHƢƠNG STUDY ON THE PROCEDURES OF THE SUPPORT ON THE SUBSTRATES TO PREPARE CATALYTIC COMPLEXES FOR THE TREATMENT OF MOTORBIKE’S EXHAUSTED GASES Chuyên ngành: K ỹ thuật hóa học Mã số: 62520301 DOCTOR OF PHILOSOPHY THESIS: CHEMICAL ENGINEERING SUPERVISOR: 1. LÊ MINH THẮNG HANOI– 2014 2 e Commitment I assure that this is my own research. All the data and results in the thesis are completely true, was agreed to use in this paper by co-authors. This research hasn‟t been published by other authors than me.
Phạm Thị Mai Phƣơng 3 e Acknowledgement This Ph.D thesis has been carried out at the Department of Organic Synthesis and Petrochemistry, School of Chemical Engineering, Hanoi University of Science and Technology during the period July 2010 to September 2013. The work has been completed under the supervision of Assoc. Le Minh Thang. Firstly, I would like to express my deepest and most sincere gratitude to my promotors: Assoc.
Le Minh Thang. She has been helping me a lot not only in the scientific work but also in my private life. Without her guidance, her encouragement, her enthusiastic and kind help, it would have been difficult to overcome the difficulties I met during the present work. I want to thank my colleagues in the lab Environment friendly Materials and Technologies for their friendly attitude towards me and their help in my work.
I would like to thank all members of the Department of Inorganic and Physical Chemistry, especially the group of Solid State Chemistry for their support and guidance during the period I was in Belgium. I am grateful to the entire member in the Advanced Institute of Science and Technology for their help, and nice environment they created for me. I especially want to express my sincere gratitude for the cooperation program between Flemish Interuniversity Council (VLIR) and Hanoi University of Technology (HUT) for the financial support for this study. I acknowledge to Prof.
Isabel Van Driessche (Coordinator of the cooperation program) for the administrative help. Finally, I lovingly thank my family for their love and encouragements during the whole long study period. 4 e Contents LIST OF ABREVIATES .8 CONTENT OF TABLES .9 CONTENT OF FIGURES .1 Air pollution caused by vehicles emission.1 Over the world and in Vietnam .2 Air pollutants from emission .3 Solutions for air pollution.2 The catalytic converter.3 Kinetic modelling of transient experiments of automotive exhaust gas catalyst .1 Principles of some synthesis methods .2 Synthesis methods of substrates and supports .5 Preparation the catalytic converters .1 Coating a monolith with a catalysis support material .2 Deposition of active phase on monolithic support. 39 Literature review‟s conclusion.6 The aim of the thesis .1 Preparation the substrates.1 Preparation of the cordierite substrate .2 Preparation of Cordierite using additives .3 Preparation of cordierite with the addition of dolomite .4 Surface treatment of prepared cordierite .5 Surface treatment of FeCr alloy substrate .2 Preparation the supports.3 Deposition methods of support on cordierite substrate .4 Deposition of support on metal substrates .5 Deposition of active catalytic phase on support/substrate .6 Preparation of the real catalytic converter .2 Characterization of surface properties by physical adsorption.3 Scanning electron microscopy (SEM) .5 X-ray photoelectron Spectroscopy (XPS) .8 Catalytic activity measurement .1 Measurement of catalytic activity in the micro-reactor connected with GC online.2 Measurement of exhausted gases.
RESULTS AND DISCUSSION.1 Synthesis of cordierite substrate .1 Influence of synthesis methods on the preparation of cordierite .2 The influence of burnable additives on the synthesis of cordierite .3 The influence of dolomite on synthesis of cordierite .4 Influence of acid treatment on surface area of cordierite .2 Preparation of FeCr metal substrate.3 Synthesis of supports .1 Synthesis of boehmite and γ-Al2 O3 .2 Synthesis of Ce0.4 Deposition of support on substrates .1 Preparation of Ce0.2 Preparation of γ-Al2 O3 support on cordierite substrate .3 Preparation of AlCe0.05 O2 support on cordierite substrate .5 Characterization of complete catalysts .1 MnO2 – NiO – Co3 O 4 /Ce0.2 MnO 2 -Co3 O4 -CeO2 /AlCe0.3 MnO 2 -Co3 O4 -CeO2 /support/ FeCr alloys .6 Catalytic activities of the complete catalysts .1 MnO2 – NiO – Co3 O4 /Ce0.2 MnO 2 -Co3 O4 -CeO2 /supports/ cordierite.3 MnO2 -Co3 O4 -CeO2 /support/ FeCr alloys .8 Catalytic activity of MnO 2 -Co3O4-CeO 2 / cordierite monolith installed in motorbike108 CONCLUSION.122 7 e LIST OF ABREVIATES Symbols Meaning NOx Nitrogen oxide THC Total hydrocarbon NMHC Non-methane hydrocarbon CO Carbon monoxide PM Particulate matter NO2 Nitrogen dioxide O3 Ozone PM10 Particulate matter less than 10 nm in diameter SO2 Sulfur dioxide NO Nitrogen oxide VOCs Volatile organic compounds HC Unburned hydrocarbons TWCs Three-way catalysts A/F Air to fuel OSC Oxygen storage capacity ACZ Al2 O3 – CeO 2 – ZrO 2 mixed oxides CZ CeO 2 – ZrO 2 mixed oxides XRD X-ray diffraction BET Brunauer, Emmett and Teller SEM Scanning electron microscopy TGA Thermogravimetric analysis DTA Differential thermal analysis XPS X-ray photoelectron Spectroscopy CTAB Cetyl trimethyl ammonium bromide SDS Sodium dodecyl sulfate PEG polyethylene glycol 8 e CONTENT OF TABLES Table 1. European Emission Standard. Emission Standards for in- used vehicles in Vietnam .3: Characteristic properties of Cordierite. TWC microkinetic scheme used in the model [66, 67].
The content (weight %) of main metal oxides in kaolin after activation. Synthesis condition of substrates samples. Synthesis conditions of supports samples. Synthesis conditions of supports deposited on substrates samples.
Synthesis conditions of catalyst samples. Standard XRD reflections of the synthesized materials. Properties of cordierite samples synthesized from different methods. Properties of synthesized Cordierite using additive.
The BET surface areas of the cordierite prepared by conventional sintering from kaolin with different addition of cellulose before sintering. Compositions of precursors to prepare cordierite. Content of cordierite phase in the product and impurities in the precursor. Contact angle of FeCr metal substrates.
Charaterization of boehmite and γ-Al2 O3. BET specific surface areas, pore sizes, pore volumes of the CZ samples. BET surface area of ACZ samples synthesized using different precipitants. The BET surface area of samples synthesized with and without aging.
The BET results of mixed oxides with different surfactants. Surface area of Ce0.8O2 /cordierite samples prepared by different deposition methods. Characterization of γ-Al2 O3 support on cordierite substrate. Atomic compositions (%) of components in Ca.
Atomic compositions (%) of components in Ca.3 catalysts by XPS 95 Table 3. Results of BET surface area of MnO2 -Co3O 4-CeO 2 catalysts. Atomic composition (%) of the commercial catalyst CAT-920 based on metal substrate. The content of emission gases with and without catalytic complex (Ca.11 - MnO 2 -Co3 O4 -CeO2 /AlCe0.
Emission of motorbike Vespa installed the commercial catalysts from Vespa based on metal substrates.110 9 e CONTENT OF FIGURES Fig. Scheme of successive two converter model [20]. Structure of three-ways catalyst [23].3: The formation of various alumina at different calcination temperature .4: Structure of γ-Al2 O3 .5: Phase diagram of the CeO 2 –ZrO2 system. IUPAC classification of hysteresis loops (revised in 1985).
Schema of micro-reactor set up. Schema of exhaust tube with a fixed catalytic converter. Schema of measuring motorbike‟s exhaust gases .1: XRD patterns of Cordierite samples prepared by various methods ……………………56 Fig. SEM image of Cordierite produced by sol-gel processing: SG-0 (a) and conventional sintering of kaolin: CV-0 (b).
TGA-DSC of cordierite samples prepared from sol- gel method. XRD pattern of cordierite sample prepared by conventional sintering calcined at 1400o C. XRD patterns of cordierite prepared by conventional sintering with different addition of. XRD patterns of cordierite prepared by sol- gel with different addition of.
SEM image of cordierite produced from kaolin without -. SEM image of cordierite produced by sol-gel processing without - SG-0 (a) and with - SG-5AC (b) the addition of activated carbon to the preforms. XRD patterns of cordierite samples prepared with different dolomite content (TX1, TD. BET surface area of HCl treated cordierite pellets (CV-0) at different periods of time.
SEM images of substrates before (a) and after hydrochloric acid treatment for 8h (b), 12h (c). XRD patterns of samples treated cordierite by hydrochloric acid. Effect of HCl acid treatment on cordierite‟s content. XRD patterns of samples with 8.% of dolomite before (TD1) and after HCl treatment (TD1.
XRD patterns of cordierite samples with 16.% of dolomite before (TD2) and after HCl treatment (TD2. Influence of acid treatment on cordierite content (a) and BET surface area (b) of the cordierite samples with addition of dolomite ( 8. The determination of contact angle of untreated (a) and treated (b) metal substrates by B3 procedure (calcined at 800 o C, then immersed in NaOH 10 wt%). XRD pattern of boehmite.
XRD pattern of γ-Al2 O3. Adsorption-desorption isotherm plots of boehmite and γ-Al2 O 3. XRD pattern of CZ28-CTAB and CZ28- non template (T: tetragonal Ce0. N 2 adsorption–desorption isotherm of samples with and without CTAB, and uncalcined and calcined (CZ28-CTAB, CZ28-CTAB as-prepared, CZ28- non template and CZ28-non template as-prepared).
XRD spectra of samples prepared using these different precipitants calcined at 550o C (NH4 HCO3-ACZ08, NH4 OH-ACZ09, KOH-ACZ10). Isotherm plots of samples prepared using these different precipitants: (a) ACZ08, (b) ACZ09, (c) ACZ10 calcined at 550o C. SEM images of samples using with different precipitants calcined at 550 o C. XRD patterns of ACZ samples with different aging conditions calcined at 550 o C.
XRD patterns of ACZ samples prepared using different surfactants calcined at 500o C (non surfactant - ACZ08, SDS surfactant-ACZ13, CTAB surfactant-ACZ14, .82 PEG 20000 surfactant- ACZ15). Mechanism of forming micelles of SDS. SEM images of mixed oxides without (ACZ08) and with surfactant SDS (ACZ13)calined at 500o C. Microscopy images of Ce0.8O2 /cordierite samples prepared by different deposition methods.
SEM images of Ce0.8 O2 /cordierite samples prepared by suspension method- Su-CZ (a), double deposition method – DD-CZ (b), and acid treated cordierite – CV-0- HCl8 (c). XRD pattern of the Ce0. SEM images of a) SG-A; b) Su-A; c) DD-A. SEM images of DD-ACZ.
XRD pattern of the complete catalyst with MnO 2 – NiO – Co3 O4 / Ce0. SEM images of final catalysts: Ca. 3 (MnO 2 – NiO – Co3 O4 / Ce0. XPS Survey of the as-prepared sample Ca.
3 (MnO 2 – NiO – Co3 O4 / Ce0. XRD pattern of MnO 2 -Co3 O4 -CeO2 /AlCe0. XRD pattern of MnO 2 -Co3 O4 -CeO2 /cordierite (Ca.40 : SEM images of MnO 2 -Co3O4-CeO 2 /cordierite (Ca.41: SEM images of MnO 2 -Co3O4-CeO 2 /AlCe0. XRD pattern of MnO 2 -Co3 O4 -CeO2 /AlCe0.05O2 /FeCr alloy (Ca.
XRD pattern of MnO 2 -Co3 O4 -CeO2 / FeCr alloy (Ca. Microscopy images of MnO 2 -Co3O4-CeO 2 deposited on FeCr substrates with and without support. SEM images of MnO 2 -Co3O4-CeO2 / FeCr alloy (Ca.8), MnO 2 -Co3O4-CeO 2 / γ- Al2 O 3 /FeCr alloy (Ca.9), and MnO 2 -Co3O 4-CeO 2 /AlCe0.05 O2 /FeCr alloy (Ca. Catalytic activities for the treatment of CO (a), C 3 H6 (b), NO (c) of MnO 2 – NiO – Co3 O4 /cordierite (Ca.
2), MnO2 – NiO – Co3 O4 / Ce0. Catalytic activity of Ce0. Catalytic activities for the treatment of (a) C 3 H6 , (b) CO of MnO 2 – Co3 O4- CeO 2 / γ-Al2 O3 /cordierite (Ca.5), MnO 2 – Co3O4-CeO 2 / Ce0.6), MnO 2 –Co3 O4-CeO2 / AlCe0.