Steady-State Simulation of a Novel Annular Multitubular Reactor for

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STEADY STATE SIMULATION OF A NOVEL ANNULAR MULTITUBULAR REACTOR FOR ENHANCED METHANOL PRODUCTION abdulaziz alarifi, Ali Elkamel, and Eric Croiset Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/ie4006589 • Publication Date (Web): 19 Sep 2013 Downloaded from http://pubs.acs.org on September 23, 2013

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Industrial & Engineering Chemistry Research

STEADY STATE SIMULATION OF A NOVEL ANNULAR MULTI-TUBULAR REACTOR FOR ENHANCED METHANOL PRODUCTION

Abdulaziz Alarifi*, Ali Elkamel, and Eric Croiset University of Waterloo Waterloo, ON, Canada N2L 3G1

Abstract In this study, a one dimensional heterogeneous model with intraparticle diffusion limitation has been developed for methanol synthesis from syngas. The synthesis gas produced from the reformer is compressed at a pressure of 60-100 bars and then heated up to 200-250 oC in order to prepare it for the methanol production reaction. Syngas reacts on a copper oxide/zinc oxide/alumina catalyst. The Annular Multi-tubular Reactor proposed in this article has a design capability to efficiently remove the heat generated by the exothermic reaction in methanol synthesis and improve methanol production by at least 3% more than the conventional convertor. Additionally, the converter is operated under mild conditions especially at the end of the tube which makes the catalyst lasts for a longer period. This leads to process intensification and allows for the use of a compact distillation step. In addition, this new design has the advantage of preheating the feed gas in the reaction by having the inner tubes replace the feed gas preheater. Methanol production and temperature profile are the most important characteristics of methanol synthesis reactor. The predicted methanol concentration and temperature profile indicate that an increase in temperature is accompanied with a reduction in the methanol equilibrium concentration and hence limiting the profitability in the industrial plant. The use of an Annular Multi-Tubular (AMT) reactor is shown to be able to overcome this limitation. The novelty lies in a process modification which employs an inner tube that is disposed in the reactor and then the catalyst is charged into a circular space surrounded by the reaction tube on one side and inner tube on the other side. Simulation studies show that this design allows the temperature to increase gradually and hence delays the equilibrium to be reached to the end of the reactor. In other word, more methanol is produced and less by-products.

Keywords Intraprticle diffusion; annular multi-tubular reactor; equilibrium concentration, process intensification, process simulation. Introduction The demand for methanol has been growing up at an average yearly rate of ten percent since 2010 and this increase is expected to potentially continue to the end of this decade. Methanol is mainly used as a raw material for formaldehyde production, accounting for almost 27% of world consumption. The use of methanol as direct fuel is the second largest market with almost 11% then acetic acid

comes as the third largest methanol end use. China is the largest consumer with almost 41% of universal consumption.1 Recently, there has been a movement towards employing methanol to replace hydrogen as a fuel for the future since it is easy to store and ready to be used in the current infrastructure of fuel stations; which is not the case with hydrogen.2 As a result, many organizations

* Corresponding author. Tel.: 519-888-4567 ext. 37157 E-mail address: [email protected]

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redirected their research focus; for instance, the U.S Department of Energy decided to stop funding hydrogen gas production and storage research from 2010 on.3 Methanol can be easily transformed to DME or directly to olefins which makes it potentially in more demand.4 Methanol technologies are licensed by numerous companies such as Davy process Technology (DPT) and Johnson Matthey Catalyst (JM), Lurgi, Mitsubishi Gas Chemical and Haldor Topsoe. Methanol technologies consist of two major stages.5 The first stage is the generation of synthesis gas (carbon monoxide and hydrogen from reforming natural gas (methane) or other heavy hydrocarbon feedstock such as crude oil, naphtha or coal. Synthesis gas from reforming or gasifying processes is characterized by a stoichiometric number, SN=(H2CO2)/(CO+CO2). The second stage is the production of methanol from the synthesis gas. The current low pressure processes operating at 50-100 bar in vapor phase is widely used to produce methanol from synthesis gas. The flow diagram is illustrated in Figure 1 where the converter is either a tubular heat exchanger (Lurgi), double-tube heat exchanger (Mitsubishi) superconverter or a multiple stage adiabatic quenching reactor (Casale methanol) and is normally used for plants requiring no steam in the synthesis unit, However it is a low cost reactor. The Superconverter is developed and owned by Mitsubishi gas chemical (MGC) and Mitsubishi Heavy Industrial (MHI) which is a simple converter having a double tubular heat exchanger where the catalyst is packed in the shell side between the inner and outer tube as shown in Figure 2. As reflected in the potential demand for methanol, many new pants have been built across the world especially in the Middle East. In the first quarter of 2008, a new mega methanol plant Ar-Razi No. 5 began on stream with an annual capacity of 1.7 million tons. This plant is located in Jubail, Saudi Arabia and owned by SABIC and a Japanese consortium led by Mitsubishi. Moreover, in 2012, Qatar fuel Additives Company awarded a contract to the Mitsubishi Heavy Industries Co. to build a new methanol plant with a capacity of 1 million tons per year. Methanol gas chemical (MGC) and Mitsubishi heavy industries (MHI) owned and patented a new methanol process including the additional humidifiers coming after the distillations which result in less amount of wasted water released to the environment while reducing the fed water to the boiler.6 In addition, they improved the performance of the converter by inventing a super converter which is basically a simple tubular heat exchanger where the catalyst is filled in the annular side between inner and outer tubes. This configuration provides a methanol process in which the distillation system is reduced in size by efficiently removing the heat generated by the reactions and inhibiting the byproducts.

1.

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Model development

1.1 Reaction kinetics Many researchers have studied the kinetics of methanol synthesis. Three main reactions are possible to occur, namely hydrogenation of carbon monoxide to methanol, hydrogenation of carbon dioxide to methanol and the reverse water- gas shift reaction. CO + 2 H2 ⇌ CH3OH CO2+3H2⇌CH3OH+H2O CO2+H2⇌CO+H2O

(1) (2) (3)

Early kinetic models were derived for the ZnO/Cr2O3 catalyst of high pressure process which has been now almost completely abandoned in favor of low pressure technology.7,8 Leonov et al.9 were the first to model methanol synthesis kinetics over a Cu/ZnO/Al2O3 catalyst. Their model again assumed CO to be the source of carbon in methanol and did not account for the influence of CO2 in the feed. Klier et.al10 considered other components as sources of carbon but assumed that CO is the most important source of carbon in methanol. Later McNeil et.al.11 expanded on the mechanism of the direct hydrogenation of CO2 and the possible role of ZnO as a hydrogen reservoir. Despite the much larger number of parameters in the resulting model, the latter authors did not manage to show a significantly better agreement between the experimental and the simulated results than that already obtained by Klier et .al10. Villa et al.12 realized that a thorough modeling of the methanol synthesis system should also involve a description of the water gas shift reaction. Graaf et al.13-15 considered both the hydrogenation of CO and CO2 as well as the water gas shift reaction. Parallel to these developments, Russian groups led by Rozovskii and Temkin16 developed a number of kinetic models for the Cu/ZnO/Al2O3 catalysts. Since neither of these groups ever succeeded in producing methanol from a dry mixture of CO and hydrogen, the models are all based on the direct hydrogenation of CO2 to methanol, while a majority also account for the occurrence of the water gas shift reaction. The present view is that methanol is formed from CO2 over copper containing catalyst. This is confirmed by C14 labeling17,18 and in-situ measurements. 19 The kinetic model proposed by Vanden Busshce and Froment20 for the conversion of syngas over Cu/ZnO/Al2O3 catalyst accurately predicts the kinetic behavior reported from other authors outside the experimental window and kinetic equations describe the influence of inlet temperature, pressure and feed composition in a physically acceptable way. In this work we have adopted the Vanden Busshce and Froment kinetic model. The main rate expressions are as follows,


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1.2 Heterogeneous model A one dimensional heterogeneous model with intraparticle diffusion limitation has been developed for an annular multi-tubular reactor. This model accounts for a double tube heat exchanger that is employed to remove the heat generated by the methanol synthesis exothermic reactions.

Figure 1: Process flow diagram of methanol synthesis.

rCH 3OH =

rRWGS

 1 p H 2O p CH 3OH  k 1 p CO2 p H 2 1 −  K eq1 p 3H p CO 2 2   p H 2O 1 + K + K ad 2 ad 1  pH2 

pH2

   

 + K ad 3 p H 2O   

3

 p H 2 O p CO   k 2 p CO 2  1 − K eq 2   p p H CO 2 2   =   p H 2O 1 + K + K ad 2 p H 2 + K ad 3 p H 2 O  ad 1   pH2  

(4)

(5) Figure 2: Schematic configuration of conventional tubular reactor (a) and double tubes reactor (b).

Equilibrium relation: 3066 − 10.592 log10 (K eq1) = T 2073 + 2.029 log10 (K eq 2 ) = − T

(6) (7)

The reaction rate and adsorption constants are of the Arrhenius form .with constants as given below in Table 1.

This new synthesis reactor is a simple double-tube type vertical exchanger. The catalyst is packed in the annual space and the boiler water circulates in the shell side (Figure 2-b). The feed gas flows first into the inner tube from the bottom toward the top and is preheated by heat generated in the catalyst bed then is collected in the top of the reactor and flows into the catalyst bed. The catalyst bed is cooled by the boiling water circulating in the shell side and the feed gas preheated in the inner tube. The mass and energy balances for the fluid phase are:

Table 1: Rate and adsorption parameters. −

 Bi   k i = Ai exp  RT 

k1 k2 k ad1 kad2 k ad3

A

B

1 dF i + A c a v k gi (F i , s − F i ) / v = 0 i = 1 ... n c L dx

dT2 − a v h f (T s − T2 ) dx 4U 4U 2 − 1 (T1 − T2 ) − (T2 − Tw ) = 0 dt1 dt 2

(8)

u g ρ g Cp g

1.07 11.22×10

-36696 10

94765

3453.38

-

0.499

17197

6.62×10

-11

124199

(9)

Where Fi and T2 are the flow rate of component i and the temperature inside the shell side, respectively. The solid phase equations are expressed by: N rxn

k gi (Fi − Fis ) / v + ρ b ∑ v j ,i η j r j = 0 j =1

a v h f (T 2 − T s ) + ρ b

N rxn

∑ η j r j (− ∆ H r , j ) = 0 j =1


(10) (11)


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The inner tube is disposed in the reaction tube to preheat the reactants while they flow upward to the top of the reactor. The tube side (feed reactants gas flow) energy balance is:

u g ρ g Cp g

dT1 4 U 1 + (T1 − T2 ) = 0 dx dt1

(12)

Where T1 is the temperature of the reactants when flow through the tube. The Ergun equation has been used to predict the pressure drop along the shell side of the reactor. dP G = − dx ρ gc d

p

1−φ   φ3 

   

 150 (1 − φ )µ  + 1 . 75 G   dp  

(13)

With boundary conditions: Fi(0)=Fi,0 , T2(0)=T2,0 , T1(1)=T1,0 and P(0)=P0.

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Table 2: Diffusion and heat transfer parameters. Parameter Effective and Kudsen diffusion coefficients. 21

Mathematical Expression

ε = s τ

Dei

 1 1   + i   Di  m Dk  4  2 Rg T  3  π Mw i

Dki = R pore nc , j ≠i

ysj

j =i

b

Multi-component molecular diffusion coefficient. 22

Dmi =

Binary diffusion coefficient. 23-25

D bi , j =

−1

   

1/ 2

∑ Di, j 0 .143 T 1 .75

(

)

Ps W m0.5 V i1 / 3 + V j1 / 3

2

1.3 Dusty-gas model for diffusion limitation in porous catalyst

Nrxn  d 2 psi 2 dpsi    + ρs ∑ vij a j rj = 0 + 10−5 RgTs R2p  dξ 2 ξ dξ  j =1

Dei

(14)

Mass transfer coefficient. 26

(15) Overall heat transfer coefficients. 27

Hence the effectiveness factor can be calculated by using this formula:

Nu number (Dixon and Cresswell. 28-29

ξ =1

1

3∫ r jξ

η

j

=

  i = k gi  p si − p bulk  ξ =1  

2

i = 1 .... n c

0

1

r sj

The diffusion and heat transfer correlations are listed in Table 2.

=

The differential and nonlinear algebraic equations of reactor model (8-13) were numerically solved by Matlab Gear's method stiff solver ode15s. This solver uses the backward differentiation formulas (BDFs) simultaneously with using fsolve for the set of nonlinear solid phase equations. Emden's equations generated by dusty-gas model were solved by Matlab boundary value problem solver bvp4c with identifying the Singular Terms 2/ξ in the program.

+

d t Bi + 3 6 λ er Bi + 4

hw d pv

λf

8βs dt / d pv

+ Nuw , Re > 50

8βs dt / d pv

+ 2 Bis

1.4 Computational Techniques

µ 1

Nuw =

=

ug

2 Rpu g

hw

(17)

−0.67

µ

Uw

=

dξ

Mw j

ρ g Dmi ×10−4

ξ =0

dp si dξ

1

k gi = 1.17×103 Re−0.42 Sci

Re=

(16)

− D ei

+

Mw

Where ξ=r/rp and the boundary conditions as follow: = 0 i = 1 .... n c

1 i

Sci = dp si dξ

2

Wmi, j =

The following sets of differential equations are the mass balances of each component along the pellet radius:

βf  λrs d pv   1+ λ f dt  λrs / λ f 

, Re < 50 Biot number. 30


Bi−1 = Bi−f1+ Bi−s1  d t   Perf    Bi f = Nu fw    RePr  2 d pv   2

 dt  −1 Bis = 0.48+ 0.192   d  pv 

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2.


Results and discussions

Model validation was carried out by comparing the model results with the process data provided by a 10 T/D pilot plant of new reactor constructed in MGC’s Niigata Plant.31 The design and catalyst specifications have been summarized in Table 3. The pilot plant used for this study has six catalyst tubes arranged circumferentially in the reactor with a length of 20 m each for the purpose of imposing severe conditions and predicting the behavior of a comparable longitudinal size used in the commercial plant. Table 3: Design and catalyst Specifications of 10T/D pilot plant constructed in MGC’s Niigata plant. Parameter

Value

Catalyst tube length Outer tube diameter Inner tube diameter Number of catalyst tubesTubes material Shell material Capacity Pressure range Catalyst type ρ s (kg m − 3 )

d p (m)

(

)

λs W m−1 K−1

(

a v m 2 m −3

ε s /τ

)

20 m 85 mm o.d. 75 mm i.d. 19 mm o.d. 17 mm i.d. 6 carbon –0.5%Mo carbon steel 10 t/d 45-110 kg/cm2 Zn/CuO/Al2O3 1214 6.53×10-3 0.004 626.98 0.123

Methanol production and temperature profile are the most important characteristics of methanol synthesis reactor. The predicted result of methanol concentration and temperature profile with the corresponding observed data are shown in Figure 3. The gas temperature peaks at the point of one meter near the catalyst tube inlet and then decreases while flowing toward the outlet. The observed reactor performance agrees well with the model results as presented in Table 4. Table 4: experimental and simulation results of pilot plant using a new methanol synthesis reactor. Parameter

Inlet

CH3OH 0.39 CO2 5.78 CO 8.93 H 2O 0.09 H2 72.06 N2 0.69 CH4 12.06 Space Velocity(h-1) Cooling Temp(oC) Temperature (oC) 150 Pressure (bar) 62.3

Outlet Observed Calculated 10.32 10.51 5.39 5.25 2.37 1.97 1.64 1.25 65.01 64.48 0.83 1.34 14.44 15.2 6260 250 215.5 217.1 4 55 56.14

A comparison study was performed in order to assess the performance of the new reactor versus the conventional tubular reactor. The latter reactor is comprised of a tube (packed with catalyst) that is externally cooled by boiler water and a nearly isothermal temperature profile is formed in the catalyst bed and aims at recovering the heat of the synthesis reaction in the form of high pressure steam to the maximum possible extent. The tube equivalent diameter of a conventional reactor was calculated to give a similar cross section area of the new reactor; both reactors have an identical amount of catalyst and have similar operating conditions. This comparison was conducted under the conditions presented in Table 5. Figure 4 shows the temperature profile of conventional reactor and double tube reactor, both are identical before reaching the peck temperature and then the conventional reactor temperature gradually decreases to reach the cooling temperature bottom line whereas the new reactor still undergoes a decreasing temperature profile towards the outlet. This latter temperature profile is very favorable in terms of reaction rate and encourages methanol to be produced.

Figure 3: Temperature profile and methanol mole percentage versus pilot plant operation for double tube reactor.



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methanol concentration profiles are almost identical; except that gas A is higher than gas B at the outlet as it has more carbon oxides and its SN ratio is closer to the optimal value.

Figure 4: Comparison of MeOH% and temperature profile along the reactor length between new reactor and conventional reactor (P=98 bar and SV=6000 h-1). The methanol mole fraction profile increases gradually and reaches 11.36% and 11.92% for the double tube exchanger and the conventional converter, respectively. Hence the production of methanol is improved by about 3% compared to the conventional convertor while at the same time the converter is operated under mild conditions especially at the end of the tube which makes the catalyst lasts longer. Furthermore, a one dimensional analysis was carried out for two different cases of feed gas compositions. The first case is a typical syngas composition produced via the combination of steam reforming and partial oxidation for natural gas reformer (gas A) and the other case is a syngas produced via steam reforming of natural gas (gas B) .

Figure 5: Effect of gas composition on gas temperature profile and methanol concentration (P=98 bar and SV=6000 h-1).

Table 5: Inlet compositions and operating conditions. Parameter CH3OH CO2 CO H 2O H2 N2 CH4 Space Velocity(h-1) Cooling Temp(oC) Feed temperature (oC) Pressure (bar)

Gas A 0 8 9 0 65 5 13

Gas B 0 5 8 0 80 1 6 3000-6000 250 150 59-98

Figure 6: Effect of pressure on temperature profiles and methanol concentration along the reactor length.

For different gas compositions, the case of rich Figure 6 shows the model results of different synthesis hydrogen content (gas B) shows a sharper temperature pressures ranging from 59 up to 98 bar. Higher synthesis peak at inlet stage of the catalyst tube than the lower pressures lead to an increase of reaction rate but the hydrogen content gas (gas A) as shown in Figure 5. The ACS Paragon Plus Environment

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removal of reaction heat becomes more difficult. Based on Le Chatelier's Principle, the production of methanol can be improved by increasing the synthesis pressure and this is in agreement with the current results. The simulations for different space velocities of feed gas are presented in Figure 7. Since the heat transfer coefficients between particles and gas film within the catalyst tube depend upon the space velocity, lower space velocity leads to lower heat transfer rate and then the temperature in the tube outlet becomes higher. As a result, methanol concentration in the tube outlet also becomes higher. However, an extremely low space velocity results in a thermal damage of the catalyst especially at the inlet of the catalyst tubes and near to the peck point.

reaches 10.36% and 10.92% for the double tube exchanger and the conventional converter, respectively. Hence the production of methanol is improved by 3% compared to the conventional convertor while at the same time its operation is under mild conditions especially at the end of the tube. This makes the catalyst lasts for a longer time. This leads to process intensification and allows for the use of a compact distillation step. In addition, this new design has the advantage of preheating the feed gas in the reaction and the inner tubes will replace the feed gas preheater.

Nomenclature

L Fi x

Ac av kgi

nc

Density of catalytic bed, kg/m3.

v

j ,i

ηj

Conclusion

mass transfer coefficient for component i ,m/ s.

ρb

N rxn

3.

Specific surface are of catalyst pellet, m2 m-3. molar flow rate of component i in the sold phase per tube, mol/s. Number of components.

F is

Figure 7: Effect of Space velocity on temperature profiles and methanol concentration along the reactor length.

tube length, m. molar flow rate of component i in the fluid phase per tube, mol/s. Dimensionless length of tube. a cross section area, m2.

Number of reactions. stoichiometric coefficient of component i in reaction j. Effectiveness factor.

rj

Rate of reaction j, mol kg-1 s-1.

ug

gas velocity, m/s.

ρg

Molar density of gas, mol/m3.

Cpg

Heat capacity of gas mixture, kJ/kmol.K .

T1 U1 dt1 T2 d t2 U2 T3

Temperature in tube 1, K.

hf

gas–solid heat transfer coefficient ,W m-2 K-1.

Ts Tw

Solid temperature, K.

Overall heat transfer coefficient for tube 1, Tube diameter of tube 1, m. Temperature in tube 2, K. Tube diameter of tube 2 ,m. Overall heat transfer coefficient for tube 2, Temperature in tube 3, K.

Coolant temperature, K.

∆H r , j

Heat of reaction j, kJ/kmol.

v

Volumetric flow rate, m3/s

The new proposed reactor design in this article has a capability to efficiently remove the heat generated by the exothermic reaction in methanol synthesis and its temperature profile is very favorable in terms of reaction rate and an increase in the production of methanol rate. The methanol mole fraction profile increases gradually and ACS Paragon Plus Environment


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References (1) Methanol Report. Nexant press. New York, NY. 2008. (2) Bromberg, L.; Cheng.,W. K. Methanol as an Alternative Transportation Fuel in the U.S.: Options for Sustainable and/or Energy-Secure Transportation Massachusetts Institute of Technology.2010. (3) Chalmers looks to replace hydrogen with methanol as future fuel. Fuel Cells Bulletin.2012, 9-10. (4) Olah, G. A. ; Goeppert, A. ; Prakash, G. K. S. Beyond Oil and Gas: The Methanol Economy. Wiley-VCH. 2009. (5) Tijm, P.J.A.; Waller, F.J.; Browna, D.M. Methanol technology developments for the new millennium. Applied Catalysis A: General. 2001, 221,275-282. (6) Kobayashi et al. Apparatus for Methanol synthesis: Mitsubishi Heavy Industries. United States Patent. 2007. US7189379B2. (7) Natta, G. Synthesis of methanol. Catalyst. 1955,3 ,349. (8) Bakemeier, H; Danner, G.A. Methanol technology and economics. Chemical engineering progress symposium series. 1970,66,98. (9) Leonov, V. E. ; Karabaev, M. M.;Tsybina, E.N.; Petrishcheva, G. S. kinet. Catal. 1973, 14,970-975. (10) Klier, K.;Chatikavanij, V.; Herman, R. G. ; Simmons G. W. Catalytic Synthesis of Methanol from CO/H2 IV. The Effects of Carbon Dioxide. Journal of Catalysis. 1982, 74, 343-360. (11) Mcneil, M. A. ;Schack , C. J. ;Rinker, R. G. Methanol Synthesis from Hydrogen, Carbon Monoxide and Carbon Dioxide over a CuO/ZnO/Al2O3 Catalyst. Applied Catalysis. 1989,50,265-285. (12) Villa, P.; Forzatti, P.; Ferraris, G.; Garone, G. ; Pasquon, I. The synthesis of alcohols from carbon dioxide and hydrogen. 1. The kinetics of the methanol synthesis. Ind. Enyng Chem. Proc. Des. Dev. 1985 ,24, 12-19. (13) Graaf, G. H.; Scholtens, H.; Stamhuis E. J.; Beenackers A.A. Intra-particle Diffusion Limitations in Low-Pressure Methanol Synthesis. Chem. Eng. Sci. 1990 ,45, 773-783. (14) Graaf, G. H.; Sijtsema, P. J.; Stsmhuis, E. J.; Joosten G. E. Chemical Equilibria in Methanol Synthesis. Chem. Eng. Sci. 1986, 41, 2883-2890. (15) Graaf, G. H.; Stamhuis, E. J.; Beenackers A. A. Kinetics of Low Pressure Methanol Synthesis. Chem. Eng. Sci. 1988, 43, 3185-3195. (16) Malinovskaya, O.A.; Rozovskii, A.Ya.; Zolotarskii, I.A. ; Lender, Yu.V. ; Matros, Yu. Sh.; Lin, G.I.; Dubovich, G.V.; Popova, N.A.; Savostina, N.V. SYNTHESIS OF METHANOL ON Cu-BASED CATALYST: KINETIC MODEL. React. Kinet. Catal. Lett. , 1987, 34, 87-92. (17) Chinchen, G.C.; Denny, P.J. ; Parker, D.G. ; Spencer, M.S. ; Waugh, K.C. ;Whan, D.A. Mechanism of methanol synthesis from CO2/CO/H2 mixtures over copper/zinc oxide/alumina catalysts-Use of C-14labeled reactants. Applied Catalysis.1987,30, 330. (18) Chinchen, G.C.; Denny, P.J.; Jennings, J.R. ;Spencer, M. S.; Waugh, K.C. Synthesis of Methanol part 1. Catalysts and kinetics. Applied Catalysis.1988, 30, 333-338. (19) Muhler, M.; Tornquist, E.; Nielsen, L.P.; Clausen, B.S.;Topsøe, H. On the role of adsorbed atomic oxygen and CO2 in copper-based methanol synthesis catalysts. Catalysis Letter. 1994, 25, 1-2.

(20) Bussche, K. M. V. ; Froment, G. F. A Steady-State Kinetic Model for Methanol Synthesis and the Water Gas Shift Reaction on a Commercial Cu/ZnO/Al2O3 Catalyst, Journal of Catalysis, 1996,161, 1-10. (21) Froment, G. F.; Bishchoff, B.Chemical Reactor Analysis and Design. John Wiley & Sons: New York. 1979. (22) Reid, R.C.; Prausnitz, J.M. ; Poling, B.E. Properties of gases and liquids. McGraw-Hill, 1988. (23) Fuller, E.N. ; Giddings, J.C. A Comparison of Methods for Predicting Gaseous Diffusion Coefficients. Journal of Chromatographic Science.1965,3, 222-227. (24) Fuller, E.N. ; Schettler, P.D. ; Giddings, J.C. A new method for prediction of binary gas-phase diffusion coefficients. Industrial & Engineering Chemistry. 1966, 58, 19-27. (25) Fuller, E.N.; Ensley, K.; Giddings, J.C. Diffusion of halogenated hydrocarbons in helium. The effect of structure on collision cross sections. J. Phys. Chem. 1969, 73, 3679-3685. (26) Cussler, E. L. Diffusion: Mass transfer in fluid systems. Cambridge University Press. 1984, 525. (27) Koning, B. Heat and Mass Transport in Tubular Packed Bed Reactors at Reacting and Non-Reacting Conditions. Twente University Press. Netherlands. 2002. (28) Dixon, A. G. An improved equation for the overall heat transfer coefficient in packed beds. Chem. Eng. and Pro. 1996, 35, 323-331. (29) Dixon, A.G.; Cresswell, D.L. theoretical prediction of effective heat transfer parameters in packed beds. AIChE J. 1979, 25, 663. (30) Dixon, A. G. Wall and Particle-Shape Effects in Heat Transfer in Packed Beds. Chem. Eng. Comm. 1988, 71, 217-237. (31) Markihara,H. ; Niwa K.; Nagai H., Morita K.; Horizoe H.; characteristics of anew methanol synthesis reactor. Energy Progress. 1978,7,51-58.


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