OPTIMIZATION OF CARBON DIOXIDE METHANATION OVER NICKEL

LOADED MESOPOROUS SILICA NANOPARTICLES USING RESPONSE

SURFACE METHODOLOGY

MOHD WAQIEYUDDIN ASHFARR BIN SAAD

A thesis submitted in fulfilment of the

requirements for the award of the degree of

Bachelor of Engineering (Chemical)

Faculty of Chemical Engineering

Universiti Teknologi Malaysia

JANUARY 2013

v

ABSTRACT

Nickel loaded mesostructured silica nanoparticles (MSN) using nickel nitrate

as metal source was prepared by impregnation method. The catalysts were

characterized by X-ray Diffraction (XRD), nitrogen physisorption and FTIR

Spectroscopy. The activity was performed on CO2 methanation and optimizes using

response surface methodology (RSM). Based on the results, Ni/MSN maintained the

hexagonal structure of mesoporous silica. An optimization of CO2 methanation over

Ni/MSN was done using four different variables: gas hourly space velocity (GHSV),

reactor temperature (Tr), time on stream (TOS) and hydrogen to carbon dioxide

molar ratio (H2/CO2). The RSM experiments were designed by using face-centered

central composite design (FCCCD) by applying 24 factorial points, 8 axial points and

2 replicates. The Pareto chart indicated that the reaction temperature have largest

effect for all responses. The optimum condition of CO2 methanation over Ni/MSN

was at time on stream of 20 min, H2/CO2 molar ratio of 4, reactor temperature of 350

○C and GHSV of 3000 ml/g∙h in which the predicted value for the CO2 conversion

was 94.5 %.

vi

ABSTRAK

Nikel yang mengandungi nanopartikel silika mesostruktur (MSN) yang

menggunakan nitrat nikel sebagai sumber logam telah disediakan melalui kaedah

pengisitepuan. Pemangkin disifatkan oleh pembelauan sinar-X (XRD), nitrogen

physisorption dan Spektroskopi FTIR. Aktiviti telah dilakukan ke atas CO2 metanasi

dan mengoptimumkan menggunakan kaedah gerak balas permukaan (RSM).

Berdasarkan keputusan, Ni/MSN masih mengekalkan struktur heksagon silika

mesoporous. Satu pengoptimuman untuk proses CO2 metanasi ke atas Ni/MSN telah

dilakukan dengan menggunakan RSM dengan empat pembolehubah yang berbeza:

halaju gas ruang sejam (GHSV), suhu reaktor (Tr), masa aliran (TOS) dan nisbah

molar hidrogen ke atas karbon dioksida (H2/CO2). Eksperimen RSM telah direka

dengan menggunakan reka muka bentuk komposit berpusat (FCCCD) dengan

menggunakan 24 mata faktorial, 8 mata paksi dan 2 replikasi. Carta Pareto

menunjukkan bahawa suhu tindak balas mempunyai kesan terbesar bagi semua

tindak balas. Keadaan optimum untuk proses metanasi CO2 ke atas Ni / MSN adalah

pada masa aliran 20 min, nisbah H2/CO2 molar 4, suhu reaktor pada 350○C dan

GHSV 3000 ml/g∙h di mana nilai yang diramalkan untuk penukaran CO2 adalah

94.5%.

vii

TABLE OF CONTENTS

CHAPTER TITLE PAGE

ACKNOWLEDGEMENT iv

ABSTRACT v

ABSTRAK vi

TABLE OF CONTENTS vii

LIST OF TABLES x

LIST OF FIGURES xi

LIST OF ABBREVIATIONS xiii

LIST OF SYMBOLS xiv

1 INTRODUCTION

1.1 General Introduction 1

1.2 Problem Statement 4

1.3 Hypothesis 5

1.4 Objective of the Study 5

1.5 Scope of the Study 6

1.6 Significance of the Study 8

2 LITERATURE REVIEW

2.1 Carbon Dioxide Utilisation 10

2.2 Hydrogenation of Carbon Dioxide 11

viii

2.2.1 Hydrogenation of Carbon Dioxide to Methanol 12

2.2.2 Hydrogenation of Carbon Dioxide to Formic acid 13

2.2.3 Hydrogenation of Carbon Dioxide to Dimethyl Ether 14

2.3 Methanation Of Carbon Dioxide 15

2.4 Mechanism Of Carbon Dioxide Methanation 17

2.5 Ni-Based Catalysts 22

2.6 Noble Metal Catalysts 23

2.7 Ceria-Zirconia as the Support for Carbon Dioxide 26

Methanation

2.8 La2O3 and Al2O3 as the Support for Carbon Dioxide 27

Methanation

2.9 Zeolite as the Support for Carbon Dioxide Methanation. 27

2.10 Catalytic Reactor as the Reactor for Carbon 28

Dioxide Methanation.

2.11 Continuous-Flow Tubular Reactor as the Reactor for 30

Carbon Dioxide Methanation.

2.12 Fixed-Bed Reactor as the Reactor for Carbon Dioxide 31

Methanation.

3 METHODOLOGY

3.1 Catalysts Preparation 32

3.1.1 Mesostructured Silica Nanoparticles Catalyst 32

3.1.2 Preparation of nickel loaded Mesostructured 33

Silica Nanoparticles (Ni/MSN)

3.2 Characterization 33

3.2.1 X-Ray Diffraction (XRD) Analysis 33

3.2.2 Transmission Electron Microscopy (TEM) 37

ix

3.2.3 Field Emission Scanning Electron Microscopy 38

(FESEM)

3.2.4 Nitrogen Adsorption Desorption Isotherms 38

3.2.5 Thermal Gravimetric Analysis (TGA) 39

3.2.6 Fourier Transform Infra Red (FTIR) Spectroscopy 39

3.2.7 Response Surface Methodology (RSM) 41

3.3 Catalytic Testing 43

4 RESULTS AND DISCUSSION

4.1 Preface 45

4.2 Properties of MSN and Ni/MSN 45

4.3 Optimization of Carbon Dioxide using RSM 51

5 CONCLUSION

5.1 Conclusion 62

REFERENCES 63

63

REFERENCES

Abe T, Tanizawa M, Watanabe K, Taguchi A. CO2 Methanation Property of Ru

Nanoparticle-Loaded TiO2 prepared by a Polygonal Barrel-Sputtering

Method. Energy Environmental Science, 2009, 2(3): 315–321

Ackermann M, Robach O, Walker C, Quiros C, Isern H, Ferrer S. Hydrogenation of

Carbon Monoxide on Ni(111) investigated with Surface X-ray Diffraction at

Atmospheric Pressure. Surface Science, 2004, 557(1–3): 21–30

Agnelli M, Kolb M, Mirodatos C. CO hydrogenation on a nickel catalyst: 1. Kinetics

and Modeling of a Low-Temperature sintering process. Journal of Catalysis,

1994, 148(1): 9–21

Arbag, H. Activity and stability enhancement of Ni-MCM-41 catalysts by Rh

incorporation for hydrogen from dry reforming of methane. International

Journal of Hydrogen Energy, 2010. 35(6): p. 2296-2304

Arakawa H, Aresta M, Armor J N, Barteau M A, Beckman E J, Bell A T, Bercaw J

E, Creutz C, Dinjus E, Dixon D A, Domen K, DuBois D L, Eckert J, Fujita E,

Gibson D H, GoddardWA, Goodman DW, Keller J, Kubas G J, Kung H H,

Lyons J E, Manzer L E, Marks T J, Morokuma K, Nicholas K M, Periana R,

Que L, Rostrup-Nielson J, Sachtler W M H, Schmidt L D, Sen A, Somorjai G

A, Stair P C, Stults B R, Tumas W. Catalysis Research of Relevance to

Carbon Management: Progress, Challenges, and Opportunities. Chemical

Scheme 2, 8 Front. Chemical Science Engineering 2011, 5(1): 2–10 Reviews,

2001, 101(4): 953–996

Barrón Cruz, A.E Pt and Ni supported catalysts on SBA-15 and SBA-16 for the

synthesis of biodiesel. Catalysis Today, 2011. 166(1): p. 111-115

B. Cornils, W. A. Hermann, CO2 Chemistry—Aqueous-Phase Organometallic

Catalysis Wiley-VCH,Weinheim, 1998, p. 488.

64

Bhatia, S., N.N. Bakhshi, and J.F. Mathews, Characterization and methanation

activity of supported nickel catalysts. The Canadian Journal of Chemical

Engineering, 1978. 56(5): p. 575-581.

Blangenois N, Jacquemin M, Ruiz P. Catalytic CO2 Methanation Process, United

States.Patent, WO2010006386, 2010-1-21

B.L. Newalkar, V.C. Nettem, T.T. Uday, R.P. Vijayalakshmi, K. Prakash, S.

Komarneni, Thirumaleshwara S.G. Bhat, Chem. Mater. 15 (2003) 1474–

1479.

Boddien, A.; Gartner, F.; Jackstell, R.; Junge, H.; Spannenberg, A.; Baumann, W. G.;

Ludwig, R.; Beller, M. ortho-Metalation of Iron(0) Tribenzylphosphine

Complexes: Homogeneous Catalysts for the Generation of Hydrogen from

Formic Acid. Angew Chemical International Edition 2010, 49, 8993.

Carrero, A., J.A. Calles, and A.J. Vizcaíno, Hydrogen production by ethanol steam

reforming over Cu-Ni/SBA-15 supported catalysts prepared by direct

synthesis and impregnation. Applied Catalysis A: General, 2007. 327(1):

p.82-94

C. Fellay, N. Yan, P. J. Dyson, G. Laurenczy, Selective Formic Acid Decomposition

for High-Pressure Hydrogen Generation: A Mechanistic Study , Chemical

Europe Journal 2009, 15, 3752 – 3760.

Chang F W, KuoMS, TsayMT, HsiehMC. Hydrogenation of CO2 over Nickel

Catalysts on Rice Husk Ash-Alumina Prepared by Incipient Wetness

Impregnation. Applied Catalysis A: General, 2003, 247(2): 309–320

Centi G, Perathoner S. Opportunities and Prospects in the Chemical Recycling of

Carbon Dioxide to Fuels. Catalysis Today, 2009, 148(3–4): 191–205

Chelsea A. Huff and Melanie S. Sanford, Cascade Catalysis for the Homogeneous

Hydrogenation of CO2 to Methanol, Journal America Chemical Soceity,

2011, 133 (45), pp 18122–18125

Chiang, J.H. and J.R. Hopper, Kinetics of the hydrogenation of carbon dioxide over

supported nickel. Industrial and Engineering Chemistry Product Research and

Development®, 1983. 22(2): p. 225-228.

Chen Y G, Tomishige K, Yokoyama K, Fujimoto K. Promoting Effect of Pt, Pd and

Rh Noble Metals to the Ni0.03Mg0.97O Solid Solution Catalysts for the

Reforming of CH4 with CO2. Applied Catalysis A: General, 1997, 165(1–2):

335–347

65

Choe S J, Kang H J, Kim S J, Park S B, Park D H, Huh D S. Adsorbed Carbon

Formation and Carbon Hydrogenation for CO2 Methanation on the Ni(111)

Surface: ASED-MO study. Bulletin of the Korean Chemical Society, 2005,

26(11): 1682–1688

Deldari, H. (2005). SUITABLE Catalysts for Hydroisomeration of Long-Chain

Normal Paraffins, .Applied Catalysis A : General. 293 : 1-10.

Dew, J. M., White, R. R. and Sliepcevitch, C. M. "Hydrogenation of Carbon Dioxide

on a Nickel - Kieselguhr Catalyst". IEC V 47, _1, Jan. 1955 p. 140-146.

E. Quaranta, M. Aresta, and 1. Tommasi, "Energy Conversion Management" Vol.

33, pp 495-504, 1991.

Falconer J L, Zagli A E. Adsorption and Methanation of Carbon Dioxide on a

Nickel/Silica Catalyst. Journal of Catalysis, 1980, 62(2): 280–285

F Ocampo, CO2 Methanation over Ni-Ceria-Zirconia Catalysts: Effect of Preparation

and Operating Conditions, 2011 IOP Conf. Ser.: Material Science

Engineering 19 012

Foger K. (1984). Metal Dispersed Catalysts. Catalysis Science and Technology. New

York : Springer

Fuertes, A.B., Synthesis of Mesostructured Silica with Tailorable Textural Porosity

and Particle Size. Materials Letters, 2004. 58(9): p. 1494-1497

Fujita S, Terunuma H, Kobayashi H, Takezawa N. Methanation of Carbon Monoxide

and Carbon Dioxide over Nickel Catalyst Under the Transient State. React

Kinet Catal Lett, 1987, 33(1): 179–184

Gattrell, M.; Gupta, N.; Co, A., A Review of the Aqueous Electrochemical

Reduction of CO2 to Hydrocarbons at Copper. Journal of Electroanalytical

Chemistry 2006, 594, (1), 1-19.

Guo F, Chu W, Xu H Y, Zhang T. Glow Discharge Plasma-Enhanced Preparation of

Nickel-Based Catalyst for CO2 Methanation. Chinese Journal of Catalysis,

2007, 28: 429–434

Hamdan, H. Design and Molecular Engineering of Nanostructured Zeolites and

Mesomorphous Material-advancing through Pores.7th Series 2003 :2-5

H.D. Setiabudi, S. Triwahyono, A.A. Jalil, N.H.N. Kamarudin, M.A.A. Aziz, Effect

of iridium loading on HZSM-5 for isomerization of n-heptane, J. Nat. Gas

Chem. 20 (2011) 477-482.

66

Huang, B. Effect of MgO promoter on Ni-based SBA-15 catalysts for combined

steam and carbon dioxide reforming of methane. Journal of Natural Gas

Chemistry, 2008. 17(3): p. 225-231

Huang, F.; Zhang, C.; Jiang, J.; Wang, Z.-X.; Guan, Catalytic Reduction of CO2 to

CH3OH with Borane Reducing Agents, H. Inorganic Chemical 2011, 50,

3816.

Huang, J. Characterization and Catalytic Activity of CeO2-Ni/Mo/SBA-15 Catalysts

for Carbon Dioxide Reforming of Methane. Chinese Journal of Catalysis,

2012. 33(4–6): p. 637-644

Huang, J. Carbon dioxide reforming of methane over Ni/Mo/SBA-15-La2O3 catalyst:

Its characterization and catalytic performance. Journal of Natural Gas

Chemistry, 2011. 20(5): p. 465-470

Jacquemin M, Beuls A, Ruiz P. Catalytic Production of Methane from CO2 and H2 at

Low Temperature: Insight on the Reaction Mechanism. Catalysis Today,

2010, 157(1–4): 462–466

Jeong, H. Effect of promoters in the methane reforming with carbon dioxide to

synthesis gas over Ni/HY catalysts. Journal of Molecular Catalysis

A:Chemical, 2006. 246(1–2): p. 43-48

J. García-Martínez, Serrano and E., G. Rus, Nanotechnology for Sustainable Energy.

Renewable and Sustainable Energy Reviews, 2009. 13(9): p. 2373-2384.

Jiménez-Morales, I. Hydrogenolysis of glycerol to obtain 1,2-propanediol on Ce-

promoted Ni/SBA-15 catalysts. Applied Catalysis B: Environmental, 2012.

117–118(0): p. 253-259

J. J. Anderson, D. J. Drury, J. E. Hamlin, Hydrogenation of Carbon Dioxide is

Promoted by a Task-Specific Ionic Liquid, A. G. Kent (BP), EP 0181078A1,

1986.

J.S. Beck, J.C. Vartuli, W.J. Roth, M.E. Leonowicz, C.T. Kresge, K.D. Schmit, C.T.-

W. Chu, D.H. Olson, E.W. Sheppared, S.B. McCullen, J.B. Higgins,

J.L.Schlenker, J. Am. Chem. Soc. 114 (1992) 10834.

Joo, F. Activation of Carbon Dioxide. Physical Inorganic Chemistry: Reactions,

Processes,and Applications; Wiley-VCH: Weinheim, Germany, 2007; pp

259.

Karelovic, A. and P. Ruiz, CO2 Hydrogenation at Low Temperature over Rh/γ-Al2O3

Catalysts: Effect of the Metal Particle Size on Catalytic Performances and

67

Reaction Mechanism. Applied Catalysis B: Environmental, 2012. 113–

114(0): p. 237-249.

Kim H Y, Lee H M, Park J N. Bifunctional Mechanism of CO2 Methanation on Pd-

MgO/SiO2 catalyst: Independent Roles of MgO and Pd on CO2

Methanation.Journal of Physical Chemistry C, 2010, 114(15): 7128–7131

Kuśmierz M. Kinetic study on Carbon Dioxide Hydrogenation over Ru/Gamma-

Al2O3 Catalysts. Catalysis Today, 2008, 137(2–4): 429–432

Kustov A L, Frey A M, Larsen K E, Johannessen T, Norskov J K, Christensen C

H.CO Methanation over Supported Bimetallic Ni-Fe catalysts: From

Computational Studies towards Catalyst Optimization. Applied Catalysis

A:General, 2007, 320: 98–104

K. Watanabe, Tominaga, K.-I.; Sasaki, Y.; Saito, M.; Hagihara, Hydrogenation of

CO2 to give Mixtures of CO, CH3OH, and CH4, T. J. Mol. Catal. 1994,

89,51.

Lallemand, M. Ni-MCM-36 and Ni-MCM-22 catalysts for the ethylene

oligomerization, in Studies in Surface Science and Catalysis, P.M.

AntoineGédéon and B. Florence, Editors. 2008, Elsevier. p. 1139-1142

Lapidus A L, Gaidai N A, Nekrasov N V, Tishkova L A, Agafonov Y A,

Myshenkova T N.The Mechanism of Carbon Dioxide Hydrogenation on

Copper and Nickel Catalysts. Petroleum Chemistry, 2007, 47(2): 75–82

Lim S, Du G A, Yang Y H, Wang C, Pfefferle L, Haller G L. Methanation of Carbon

Dioxideon Ni-Incorporated MCM-41 Catalysts: The influence of catalyst

pretreatment and study of steady-state reaction. Journal of Catalysis, 2007,

249(2): 370–379

Lindo, M. Ethanol steam reforming on Ni/Al-SBA-15 catalysts: Effect of the

aluminium content. International Journal of Hydrogen Energy, 2010. 35(11):

p. 5895-5901

Liu, D. Carbon dioxide reforming of methane to synthesis gas over Ni-MCM-41

catalysts. Applied Catalysis A: General, 2009. 358(2): p. 110-118

Liu, H. Preparation, characterization and activities of the nano-sized Ni/SBA-15

catalyst for producing COx-free hydrogen from ammonia. Applied Catalysis

A:General, 2008. 337(2): p. 138-147

68

Lee G D, Moon M J, Park J H, Park S S, Hong S S. Raney Ni catalysts derived from

different alloy precursors Part II. CO and CO2 methanation activity. Korean J

Chem Eng, 2005, 22(4): 541–546

Luo, M. and B.H. Davis, Fischer–Tropsch synthesis: Group II Alkali-Earth Metal

Promoted Catalysts. Applied Catalysis A: General, 2003. 246(1): p. 171-181.

M. Aresta, IEA-OECD Expert Seminar on "Energy Technologies for Reducing the

Emission of Greenhouse Gases", Paris, 12-14 April 1989, IEAOECD

Publications Vol 1, p. 599-617, 1989.

Marwood M, Doepper R, Renken A. In-Situ Surface and Gas Phase Analysis for

Kinetic Studies Under Transient Conditions: The Catalytic Hydrogenation of

CO2. Applied Catalysis A: General, 1997, 151(1): 223–246

M.M. Halmann and M. Steinberg, Greenhouse Gas Carbon Dioxide Mitigation:

Science and Technology, CRC Press, 1998

Omegna, A.; van Bokhoven, J. A.; Prins, R. Flexible Aluminum Coordination in

Alumino Silicates: Structure of Zeolite H_USY and Amorphous Silica

Alumina. J. Phys. Chem. B 2003, 107, 8854.

Park J N, McFarland E W. A Highly Dispersed Pd-Mg/SiO2 Catalyst Active for

Methanation of CO2. Journal of Catalysis, 2009, 266(1): 92–97

Park,S.J. and S.Y. Lee, A study on hydrogen-storage behaviors of nickel-loaded

mesoporous MCM-41. Journal of Colloid and Interface Science, 2010.

346(1): p. 194-198

Park, Y. Single-step preparation of Ni catalysts supported on mesoporous silicas

(SBA-15 and SBA-16) and the effect of pore structure on the selective

hydrodechlorination of 1,1,2-trichloroethane to VCM. Catalysis Today, 2004.

97(2–3): p. 195-203

P.D. Haaland, Experimental Design in Biotechnology, Marcel Dekker Inc., New

York, 1989.

Peebles D E, Goodman D W, White J M. Methanation of Carbon Dioxide on Nickel

(100) and the Effects of Surface Modifiers. Journal of Physical Chemistry,

1983, 87(22): 4378–4387

Peng, X. D.; Wang, A. W.; Toseland, B. A.; Tijm, P. J. A. Single- Step Syngas-to-

Dimethyl Ether Processes for Optimal Productivity, Minimal Emissions, and

Natural Gas-Derived Syngas. Ind. Eng. Chem. Res. 1999, 38, 4381

69

P. G. Jessop in The Handbook of Homogenous Hydrogenation, Vol. 1 (Eds.: J. G. de

Vries, C. J. Elsevier), Wiley-VCH, Weinheim, 2007, pp. 490 – 499

Preti, D. Carbon Dioxide Hydrogenation to Formic Acid by Using a Heterogeneous

Gold Catalyst. Angewandte Chemie International Edition, 2011. 50(52):

p.12551-12554

Ren, J. Hydrodesulfurization of dibenzothiophene catalyzed by Ni-Mo sulfides

supported on a mixture of MCM-41 and HY zeolite. Applied Catalysis

A:General, 2008. 344(1–2): p. 175-182

Ren, S. Promotion of Ni/SBA-15 catalyst for hydrogenation of naphthalene by

pretreatment with ammonia/water vapour. Catalysis Communications, 2010.

12(2): p. 132-136

Riduan, S. N.; Zhang, Y.; Ying, Catalytic Reduction of CO2 to CH3OH with Silane

Reducing Agents, J. Y. Angewandte. Chemie International Edition 2009,

48, 3322

R.J. Shang, W.Z. Sun, Y.Y. Wang, G.Q. Jin, X.Y. Guo, Catalysis Communications 9

(2008) 2103–2106

R.Williams, R. S. Crandall, A. Bloom, Use of Carbon Dioxide in Energy Storage,

Applied Physical Letter. 1978, 33, 381 – 383

Satterfield, C.N (1991). Heterogenous Catalysis in Industrial Practice, 2nd ed.

McGraw Hill: New York

Sane S, Bonnier JM, Damon J P, Masson J. Raney metal catalysts: I. Comparative

Properties of Raney Nickel Proceeding from Ni-Al Intermetallic Phases.

Applied Catalysis, 1984, 9(1): 69–83

Sehested, J. Methanation of CO over Nickel:  Mechanism and Kinetics at High

H2/CO Ratios†. The Journal of Physical Chemistry B, 2004. 109(6): p. 2432-

2438

Sehested J, Larsen K E, Kustov A L, Frey A M, Johannessen T, Bligaard T,

Andersson M P,Norskov J K, Christensen C H. Discovery of Technical

Methanation Catalysts based on Computational Screening. Topics in

Catalysis, 2007, 45(1–4): 9–13

Stiles, A. B (1987). Catalysts Supports and Supported Catalysts. Butterworths:

London

70

Song H L, Yang J, Zhao J, Chou L J. Methanation of Carbon Dioxide over a Highly

Dispersed Ni/La2O3 Catalyst. Chinese Journal of Catalysis, 2010, 31(1): 21–

23

Sun, D. Effect of O2 and H2O on the tri-reforming of the simulated biogas to syngas

over Ni-based SBA-15 catalysts. Journal of Natural Gas Chemistry, 2010.

19(4): p. 369-374

Szailer T, Novak E, Oszko A, Erdohelyi A. Effect of H2S on the Hydrogenation of

Carbon Dioxide over Supported Rh Catalysts. Topics in Catalysis, 2007,

46(1–2): 79–86

Szegedi, Á. Synthesis and characterization of Ni-MCM-41 materials with spherical

morphology and their catalytic activity in toluene hydrogenation.Microporous

and Mesoporous Materials, 2007. 99(1–2): p. 149-158

Thomas, J.M. and Thomas, W.J. (1997). Principles and Practice Of Herogeneous

Catalysis. Germany : VCH, Weinheim

T. Schaub, R. A. Paciello, A Process for the Synthesis of Formic Acid by CO2

Hydrogenation: Thermodynamic Aspects and the Role of CO, Angew. Chem.

2011, 123, 7416 – 7420; Angewandte. Chemie. International. Edition. 2011,

50, 7278 – 7282, and references therein

VanderWiel D P, Zilka-Marco J L, Wang Y, Tonkovich A Y, Carbon Dioxide

Methanation on a Ruthenium Catalyst. Industrial & Engineering Chemistry

Process Design and Development, Wegeng R S. In: Spring National Meeting.

Atlanta: AIChe, 2000

Vannice M A. The Catalytic Synthesis of Hydrocarbons from H2/CO Mixtures over

the Group VIII Metals: IV. The Kinetic Behavior of CO Hydrogenation over

Ni Catalysts. Journal of Catalysis, 1976, 44(1): 152–162

Wan, H. Effect of Ni Loading and CexZri-xO2 Promoter on Ni-Based SBA-15

Catalysts for Steam Reforming of Methane. Journal of Natural Gas

Chemistry, 2007. 16(2): p. 139-147

Wasilke, J.-C.; Obrey, S. J.; Baker, R. T.; Bazan, Examples of Homogeneous

Catalytic CO2 Reduction, Gas Chromatic Chemical. Review. 2005, 105,1001

Weatherbee G D, Bartholomew C H. Hydrogenation of CO2 on group VIII Metals: I.

Specific Activity of Ni/SiO2. Journal of Catalysis, 1981, 68(1): 67–76

Wei, X. Alkali-metal fullerides MC60 (THF)x (M=Li, Na, K): a New Solution-

PhaseMethod for the Preparation and Characterization with ESR, UV–NIR

71

and IR Spectroscopy. Journal of Organometallic Chemistry, 2000.599(1): p.

69-73

Wu, C. Hydrogen production from biomass gasification with Ni/MCM-41 catalysts:

Influence of Ni content. Applied Catalysis B: Environmental, 2011.108–

109(0): p. 6-13

Wojcieszak, R. Nickel containing MCM-41 and AlMCM-41 mesoporous molecular

sieves: Characteristics and activity in the hydrogenation of benzene. Applied

Catalysis A: General, 2004. 268(1–2): p. 241-253

W. Reutemann, H. Kieczka in Formic Acid—Ullmann’s Encyclopedia of Industrial

Chemistry, Electronic Release, 7th ed., Wiley-VCH, Weinheim, 2009

Yang, G. H.; Tsubaki, N.; Shamoto, J.; Yoneyama, Y.; Zhang, Y. Confinement

Effect and Synergistic Function of H-ZSM-5/ CuZnO Al2O3 Capsule

Catalyst for One-Step Controlled Synthesis. Journal America Chemical

Soceity 2010, 132, 8129.

Yang, X., Hydrogenation of Carbon Dioxide Catalyzed by PNP Pincer Iridium, Iron,

and Cobalt Complexes: A Computational Design of Base Metal Catalysts.

America Chemical Soceity Catalysis, 2011. 1(8): p. 849-854.

Yu K P, Yu W Y, Kuo M C, Liou Y C, Chien S H. Pt/titaniananotube: A Potential

Catalyst for CO2 Adsorption and Hydrogenation. Applied Catalysis B:

Environmental, 2008, 84(1–2): 112–118

Yu. M. Serov and T. F. Sheshko, Combined Hydrogenation of Carbon Oxides on

Catalysts Bearing Iron and Nickel Nanoparticles,Russian Journal of Physical

Chemistry A, Focus on Chemistry, 2011, Volume 85, Number 1, Pages 51-54

Zhang, J. Synthesis and Characterization of Alkali-Metal Aryloxo Compounds and

their Catalytic Activity for l-lactide Polymerization. Polyhedron, 2011.

30(11): p. 1876-1883

Zhang, M. Structural Characterization of Highly Stable Ni/SBA-15 Catalyst and Its

Catalytic Performance for Methane Reforming with CO2. Chinese Journal of

Catalysis, 2006. 27(9): p. 777-781

Zhang, Q.; Zuo, Y. Z.; Han, M. H.; Wang, J. F.; Jin, Y.; Wei, F. Long Carbon

Nanotubes Intercrossed Cu/Zn/Al/Zr Catalyst for CO/ CO2 Hydrogenation to

Methanol/Dimethyl Ether. Catalysts Today 2010, 150, 55.