Computation of effectiveness factor for methanol steam reforming over Cu/ZnO/Al2O3 catalyst pellet

Applied Petrochemical Research - 2020
Abayomi O. Olatunde1, O. A. Olafadehan1, Mohammed Awwalu Usman1
1Department of Chemical and Petroleum Engineering, University of Lagos, Lagos, Nigeria

Tóm tắt

AbstractA mathematical model was developed for a diffusion–reaction process in a spherical catalyst pellet contained in a heterogeneous packed bed reactor. The model developed was solved to predict the effectiveness factor and also to perform sensitivity analysis for steam reforming of methanol on Cu/ZnO/Al2O3 catalyst a source of hydrogen fuel. The method of orthogonal collocation was used to solve the resulting differential equation. At temperature below 473 K the effect on intra-particle diffusion limitation is reduced to the minimum indicated by the effectiveness factor being almost equal to one but as the temperature increases above 473 K there is considerable increase in the diffusion limitation effect. The effects of thermal conductivity, diffusion coefficient, catalyst size and surface temperature on effectiveness factor for the reaction process were also considered. Result indicates that catalyst size of $$1.623\,\, \times \,\,10^{ - 4}$$1.623×10-4 m eliminates the effect of intra-particle diffusion resistance in the pellet. The variation of effectiveness factor with Thiele modulus, showing the asymptotic values, using power law and Langmuir–Hinshelwood–Hougen–Watson (LHHW) kinetics, was predicted. The two reaction kinetics had almost the same magnitude of effectiveness factor at different Thiele modulus which indicates that they can adequately predict the reaction process.

Từ khóa


Tài liệu tham khảo

Agarwal V, Patel S, Pant KK (2005) H2 production by steam reforming of methanol over Cu/ZnO/Al2O3 catalysts: transient deactivation kinetics modelling. Appl Catal A Gen 279:155–164

Brown LF (2001) A comparative study of fuels on-board hydrogen production for fuel-cell powered automobile. Int J Hydrog Energy 106(1–2):249–257

Joensen F, Rostrup-Nielsen JR (2002) Conversion of hydrocarbons and alcohols for fuel cells. J Power Sources 105(2):195–201

Lee JK, Ko JB, Kim DH (2004) Methanol steam reforming over Cu/ZnO/Al2O3 catalyst: kinetics and effectiveness factor. Appl Catal A Gen 278:25–35

Amphlett JC, Evans MJ, Mann RF, Weir RD (1985) Hydrogen production by catalytic steam reforming of methanol. Part 2; Kinetics of methanol decomposition using girdler G66B catalyst. Can J Chem Eng 63:605–611

Jiang CJ, Trimm DL, Wainwright MS, Cant NW (1993) Kinetic study of steam reforming of methanol over copper based catalyst. Appl Catal A Gen 93:245–255

Jiang CJ, Trimm DL, Wainwright MS, Cant NW (1993) Kinetic mechanism for the reaction between methanol and water over Cu/ZnO/Al2O3 catalysts. Appl Catal A Gen 97:145–158

Idem RO, Bakshi NN (1996) Kinetics modelling of the production of hydrogen from methanol-steam reforming process over Mn-promoted coprecipitated Cu-Al catalyst. Chem Eng Sci 51(14):3697–3708

Peppley BB, Amphlett JC, Kearns LM, Mann RF (1999) Methanol steam reforming on Cu/ZnO/Al2O3 catalyst—part 1: the reaction network. Appl Catal 179:21–29

Giessler K, Newson E, Vogel F, Truong TB, Hottinger P, Wokaun A (2001) Autothermal methanol reforming for hydrogen production in fuel cell applications. Phys Chem Chem Phys 3:289

Samm SR, Savinell RF (2002) Kinetics of methanol-steam reformation in an internal reforming fuel cell. J Power Sources 112:13–29

Lim MS (2001) The Production of Hydrogen from Methanol in PEMFC System. Ph.d Thesis, Kyungpook National University, Taegu

Purnama H, Ressler T, Jentoft RE, Soerijanto H, Schögl R, Schomäcker R (2003) CO formation/selectivity for steam reforming of methanol with a commercial Cu/ZnO/Al2O3 catalyst. Appl Catal A 259:83–90

Santacesaria E, Carra S (1983) Kinetics of catalytic steam reforming of methanol in a CSTR reactor. Appl Catal 5:345–358

Agrell J, Birgersson H, Boutonnet M (2002) Steam reforming of methanol over a Cu/ZnO/Al2O3 catalyst: a kinetic analysis and strategies for suppression of CO formation. J Power Sources 106(1–2):249–257

Ledjeff-Hey K, Formanski V, Kalk T, Ross J (1998) Compact hydrogen production systems for solid polymer fuel cells. J Power Sources 71(1–2):199–207

Wiese W, Emonts B, Peters R (1999) Methanol steam reforming in a fuel cell drive system. J Power Sources 84(2):187–193

Peters R, Dűsterwald HG, Höhlein B (2000) Investigation of a methanol reformer concept considering the particular impact of dynamics and long-term stability for use in a fuel-cell powered passenger car. J Power Sources 86(1–2):507–514

Schneider P (1976) Intraparticle diffusion in multicomponent catalytic reactions. In: Heinemann H, Carberry JJ (eds) Catalysis Reviews, Science and Engineering, vol 12. Marcel Dekker, New York, pp 201–278

Schneider P (1998) Effectiveness factor for a non-isothermal simple catalytic reaction with combined transport processes: Maxwell-Stefan approach. Collect Czech Chem Commun 63:252–270

Villadsen JW, Stewart WE (1967) Solution of boundary value problems by orthogonal collocation. Chem Eng Sci 22:1483–1501

Villadsen JW, Michelsen ML (1978) Solution of differential models by polynomial approximation. Prentice-Hall Inc, Englewood Cliff

Feng C, Stewart WE (1973) Practical models of isothermal diffusion and flow of gases in porous solids. Ind Eng Chem Fundam 12(2):143–147

Haugaard J, Livbjerg H (1998) Models of pore diffusion in porous catalysts. Chem Eng Sci 53(16):2941–2948

Smith JM (1981) Chemical engineering kinetics, McGraw-Hill chemical engineering series, 3rd edn. McGraw-Hill Inc, New York, USA

Reid RC, Prausnitz JM, Poling BE (1998) The properties of gases and liquids, 4th edn. McGraw-Hill, New York, USA

Yagi S, Wakao N (1959) Heat transfer and mass transfer from wall to fluid in packed beds. Am Inst Chem Eng J 5(1):79–85

Iordanidia AA (2002) Mathematical modelling of catalytic fixed bed reactors. Ph.D. Thesis of Twente University Press, Enschede, The Netherlands

Papavasilous J, Avgouropoulos C, Ioannides T (2004) Production of hydrogen via combined steam reforming of methanol over catalyst. Catal Commun 5:231–235

Suh J, Lee M, Greif R, Grogoropoulos CP (2009) Transport phenomena in a steam-methanol reforming microreactor with internal heating. Int J Hydrogen Energy 14:1–26

Thông tin
Thông tin xuất bản

Applied Petrochemical Research

Thông tin tác giả