Development of a Deactivation Model for the Dehydration of 2,3

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Development of a Deactivation Model for the Dehydration of 2,3-Butanediol to 1,3-Butadiene and Methyl Ethyl Ketone over an Amorphous Calcium Phosphate Catalyst Daesung Song Ind. Eng. Chem. Res., Just Accepted Manuscript • DOI: 10.1021/acs.iecr.7b02355 • Publication Date (Web): 14 Sep 2017 Downloaded from http://pubs.acs.org on September 14, 2017

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Industrial & Engineering Chemistry Research

Development of a Deactivation Model for the Dehydration of 2,3-Butanediol to 1,3-Butadiene and Methyl Ethyl Ketone over an Amorphous Calcium Phosphate Catalyst

Daesung Songa,* a

Global Technology, SK innovation, 325 Exporo, Yuseong-gu, Daejeon 305-712, Republic of

Korea

To whom correspondence should be addressed: Daesung Song Tel: +82-10-9312-6098. E-mail: [email protected]

1 Environment ACS Paragon Plus


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Abstract A deactivation model for the dehydration of 2,3-Butanediol (2,3-BDO) to 1,3-Butadiene (1,3BD) and Methyl Ethyl Ketone (MEK) on an amorphous calcium phosphate (a-CP) catalyst is herein proposed. The deactivation of a-CP catalyst can be explained by the following steps: (i) 1,3-BD selectivity is increased sharply as the temperature increases. (ii) the high 1,3-BD selectivity and temperature raise a possibility of the polymerization of 1,3-BD. (iii) heavy compounds made by polymerization covers the active surface of the catalyst and blocks the pores of the catalyst. Deactivation data for around 86 h that are obtained from a laboratory-scale fixedbed reactor operated under isothermal conditions were found to be modeled well using the simplified concentration-independent generalized power law expression (GPLE) of the form

dα / dt = -K d (α − α eq ) m . The values of deactivation order m, the limiting activity at infinite time α eq and the activation energy for deactivation Ed are found to be 1.32, 0.33 and 1.00E+06 J/mol, respectively. Also, it is checked that the activity of a-CP catalyst maintains constant after the regeneration through the same experiment conducted with the regenerated a-CP catalyst. 1. Introduction Methyl Ethyl Ketone (MEK) and 1,3-Butadiene (1,3-BD) are important intermediates for the chemical industry. The majority of MEK is used as organic solvent for paints and coatings and the overall consumption of MEK in 2014 was over 1,000 metric tons1. 1,3-BD is a conjugated diene that is used in the production of polymers and as a chemical intermediate for several specialty products. The single largest use for butadiene is in the production of synthetic elastomers, which are then used to manufacture tires. The consumption of 1,3-BD in 2015 was over 10,000 metric tons2.


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Both compounds are mostly produced from petroleum that is a major cause of environmental pollution and a finite resource. As an environmentally friendly alternative, 1,3-BD and MEK can also be produced via the dehydration of 2,3-Butanediol (2,3-BDO), which is produced through bio-fermentation by various microorganisms3. Various types of biomass, syngas from coal gasification, and industrial gas waste can be used as a feedstock. This technology is worth developing because it can extend the feedstock rather than petroleum. Several research group have studied the dehydration of 2,3-BDO to 1,3-BD or MEK using various catalysts since the 1940s4-24. Most research was focused on developing dehydration catalysts or reaction conditions that show good performance. Recently, the reaction kinetics of the dehydration of 2,3-BDO to 1,3-BD and MEK was defined over an amorphous calcium phosphate (a-CP) catalyst and a kinetic model proposed in order to explain the dehydration reaction of 2,3-BDO to 1,3-BD and MEK using an a-CP catalyst25. Also, a process design that is for the recovery of 1,3-BD and MEK from BDO-dehydration products, which were obtained from experimental data, was proposed as a conceptual design for the industrial scale26. Duan et al. summarized performance of dehydration of 2,3-BDO over several catalysts20. The major target products of the catalysts are MEK, 1,3-BD, or 1,3-BD and MEK. Zhang et al. have reported Bmodified HZSM-5 Catalysts effectively work in the dehydration of 2,3-BDO to produce mainly MEK. The catalysts showed 100% conversion, 70% MEK and 1.4% 1,3-BD selectivity at 200oC13. Tsukamoto et al. achieved over 99.9% conversion, the highest 1,3-BD selectivity(>90%) and 7% MEK at around 400 oC using the SiO2-supported CsH2PO4for at least 8h of reaction time22. Winfield disclosed 100 conversion, 62% 1,3-BD and 26% MEK selectivity at 500oC using ThO24. The a-CP showed 100 conversion, 55% 1,3-BD and 39% MEK selectivity, based on hydrocarbons at 335oC for at least 33.6h of reaction time. In comparison with ThO2, 1,3-BD



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selectivity is lower but total selectivity of 1,3-BD and MEK is higher. Also, the operating temperature is lower than ThO2. It would be more competitive to produce both 1,3-BD and MEK by using a-CP in a commercial process. Moreover, a kinetic model is only developed for the dehydration of 2,3-BDO to 1,3-BD and MEK on the a-CP catalyst. While knowledge about catalyst deactivation and reaction kinetics is also an essential part for the design and operation of industrial chemical reactors, no research has been conducted on a deactivation model for the dehydration of 2,3-BDO to 1,3-BD and MEK. This paper will show how a-CP catalyst deactivates and present a suitable deactivation model for the dehydration of 2,3-BDO to 1,3-BD and MEK over an a-CP catalyst. The deactivation parameters were determined by fitting the experimental data obtained from a laboratory-scale fixed-bed reactor operated under isothermal conditions. The proposed deactivation model is novel as it characterizes the a-CP catalyst's deactivation. An experiment using the regenerated aCP catalyst was carried out to test the catalyst activity after regeneration. The experimental data, deactivation model, and analysis are expected to contribute to the design and operation of commercial-scale 2,3-BDO dehydration reactors. 2. Experimental 2.1. Deactivation and regeneration experiments 2.2.1. Experimental setup. For this study, the catalysts were prepared and the deactivation experiments were conducted following the procedures published by Song25. The surface area, pore diameter, and pore volume of the catalyst were 37.4 m2/g, 292.3 Å and 0.25 cc/g, respectively. The catalytic reactions were


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carried out in a conventional continuous flow fixed-bed reactor(3/8'' quartz) that was operated isothermally under atmospheric pressure. 0.3g of catalyst subjected to a sieve to produce an average particle size of 100  m was loaded into the center of the reactor. 2,3-BDO (98%, Sigma-Aldrich) were introduced via a syringe pump under N2 flow (carrier gas) at a rate of 10cc/min (standard ambient temperature and pressure, SATP) that was controlled with a massflow controller. Before each experiment, the fresh catalyst was pretreated in N2 flow (10cc/min) at 400oC for 1 h. The temperature of the reactor was monitored by using a K-type thermocouple with a measurement accuracy ±0.2%. The reaction performances were evaluated by determining the conversion and selectivity data every 4 h over 86 h. In order to estimate deactivation parameters, three long-term experiments were performed. Table 1. shows the experimental conditions for tests 1-3. In previous research, experiments were performed using a mixture of 2,3-BDO, 3-Buten-2-ol(3B2OL) and N2 as feed, at temperatures ranging from 304 to 334.5oC and gas hourly space velocity (GHSV) ranging from 1780 to 2222 h-1. The estimated kinetic parameters with the experiments indicate that the reaction orders(n1, n3, n4: 0.0187 and n2: 0.146) shown in Table S1 in the Supporting Information are very close to 0, meaning that reactor performance for 2,3-BDO dehydration is mainly determined by the temperature of the reactor25. Therefore, the deactivation experiments were implemented with varying reaction temperature. Table 1. Experimental Conditions Test

Temperature [oC]

2,3-BDO [g/h]

N2flow [cc/min]

GHSV* [/h]

1

324.5

0.73

10

1843

2

329.7

0.73

10

1859



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3

334.5

0.73

10

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1874

* based on the inlet conditions of the reactor A regeneration experiment with the used a-CP catalyst from test 3 was carried out using the same conventional continuous flow fixed-bed reactor (3/8'' quartz) for the deactivation experiments. The used catalyst was regenerated with a mixture flow (10cc/min) composed of 20% O2 and 80% N2 at 500oC for 8 h. 2.2.2. Analysis of reaction products. Product compositions were analyzed in an online gas chromatograph (GC, Agilent 7890A) with a DB-1 column (non-polar phase, 60m x 0250mm x 1  m ) and a FID (Flame Ionization Detector) for the analysis of hydrocarbon content. The composition of water was calculated by reaction stoichiometry of eqs 3-6 in section 3.1 based on the compositions of 3-Buten-2-ol (3B2OL), 1,3-BD, MEK, and 2-Methylpropanal (2MPL) in the products. The compositions of major components were normalized to remove the effects of the impurities25. The conversion of 2,3-BDO and selectivity for each product was computed as follows:

= X BDO

Sn

FBDO ,in − FBDO ,out FBDO ,in Fn ,out

Ftotal − FBDO ,out − FN2

×100

(1)

×100

(2)

where X2,3-BDO is the conversion of 2,3-BDO, n is a component of the product, S is the mass selectivity, and F is the mass flow rate.


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1 2 3 3. Modeling 4 5 6 3.1. Reactor model 7 8 9 10 The reaction kinetics of the dehydration of 2,3-BDO to 1,3-BD and MEK using a-CP as a 11 12 catalyst in previous research was used for the reactor model25. The major pathways of 2,3-BDO 13 14 dehydration are described by the following reactions: 15 16 17 r1 18 (3) C4 H10O2  → C4 H 8 O + H 2 O 19 (2,3− BDO ) (3 B 2 OL ) 20 21 22 r2 (4) → C4 H 6 + H 2 O C4 H 8O  23 (3 B 2 OL ) (1,3− BD ) 24 25 26 r3 (5) 27 C4 H10O2  → C4 H 8 O + H 2 O − (2,3 BDO ) ( MEK ) 28 29 30 31 r4 C4 H10O2  → C4 H 8 O + H 2 O (6) 32 (2,3− BDO ) (2 MPL ) 33 34 35 The reaction rates based on the power law are: 36 37 38 39 ri = ki Creact ,i ni (7) 40 41 42 43 where 44 45 46 Pj 47 Cj = (8) 48 RT 49 50 51 52 −E 1 1 )) = ki kTref ,i exp( i ( − (9) 53 R T T ref 54 55 56 57 58 59 60



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where i is the number of reaction, r is the reaction rate, react is the reactant, C is the mole concentration, n is the reaction order, j is the number of species, P is the pressure, R is the ideal gas law constant, T is the temperature in bulk gas phase, k is the reaction rate constant, kTref is the transformed adsorption pre-exponential factor, E is the activation energy, and Tref is the reference temperature. The kinetic parameter values are shown in Table S1 in the Supporting Information25. The same reactor model used in previous research25 was used here except for adding a time term and catalyst activity in the model for the deactivation study. The dynamic one-dimensional homogeneous model takes the form dC j

rxn d (us C j ) = − + ρbα ∑ν ji ri dt dz i =1

(10)

where z and t are the axial reactor coordinate and time, respectively, us is the superficial fluid velocity, ρb is the bulk density of the catalyst bed, α (1≧ α ≧0) is the catalyst activity, rxn is the number of reactions, and υ ji is the stoichiometric coefficient of species j in reaction i. The reactor model was integrated by employing DASOLV, a differential algebraic solver included in the General Process Modeling System (gPROMS) library27. 3.2. Development of a deactivation model Mechanisms of deactivation for the dehydration of 2,3-BDO to 1,3-BD and MEK over an a-CP catalyst have not yet been defined. In previous research, major and minor pathways of 2,3-BDO dehydration were proposed, as shown in Figure 125. It has further been suggested that the pathway to coke, starting from olefins or aromatics, may involve (a) dehydrogenation to olefins,(b) olefin polymerization, (c) olefin cyclization to form substituted benzenes, and (d)


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formation of polynuclear aromatics from benzene28-30. Based on major and minor pathways of 2,3-BDO dehydration and the pathway to coke explained above, it is expected that the major product, 1,3-BD, forms heavy compounds through polymerization and these heavy compounds cover the active surface of the catalyst and block the pores of the catalyst.

-H2 O

Oligomerization Heavy compounds 1,3-BD

-H2 O

3B2OL

+H2

-H2 O

-H2 O MEK

2,3-BDO -H2 O

? 2MPL

Heavy compounds

Figure 1. Major (solid arrows) and minor (dashed arrows) pathways of 2,3-BDO dehydration25 Table S2 in the Supporting Information shows the result of element analysis (EA-CHNS method) for the fresh and the used a-CP catalyst of test 3. After test 3, coke deposits made up around 13 wt % of the catalyst and accordingly these may deactivate the catalyst by either pore blocking or by covering the catalytic sites for acidity. X-ray photoelectron Spectroscopy analysis showed that the Ca/P ratio of a-CP catalyst was not changed. The catalyst had very few



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micropores because the surface area (37.4 m2/g) is small and the pore diameter (292.3Å) is large, which means that the coke deposits could be eliminated easily. Much work related to catalyst deactivation models by coke has been done. In a pioneering work, Voorhies31 empirically described coke formation as a function of time-on-stream. Froment and Bishoff relate the rate of coke formation to the composition of the reacting mixture, catalyst temperature and catalyst activity. On the other hand, Szepe and Levenspiel32 relate the catalyst activity directly to time with several empirical functions. Generalized power law expression (GPLE) for modeling of catalyst deactivation are developed by Fuentes33. Use of this method allows a correct analysis of most deactivation pattern. The deactivation model of the catalyst for the dehydration of 2,3-BDO to 1,3-BD and MEK has not yet been studied. Therefore, empirical functions (DM1-2) that relate the catalyst activity directly to time and a simplified concentrationindependent generalized power law expression (DM3) were used to describe the catalyst activity as a first step. The key distinction of the GPLE model is that catalyst activity does not decline to zero at large times, but instead approaches a constant, non-zero activity asymptotically33.

-b dCW rxn ), ri = ∑ CW dt i =1

(11)

(1 − b) dCW rxn , ri = ∑ (1 + aCW ) dt i =1

(12)

DM1: α = 1 - aexp(

DM2: α = b +

DM3:

−E 1 dα 1 = -K d= (α − α eq ) m , K d - K d _ ref exp( d ( − )) dt R T Tref

(13)

where a and b are parameters to be estimated, CW is the cumulative work done by the catalyst, Kd is the deactivation rate constant, m is the deactivation order, α eq is the limiting activity at


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infinite time, Kd_ref is the transformed deactivation pre-exponential factor, and Ed is the activation energy for deactivation. 3.3. Estimation of parameters The reactor model in section 3.1 was used to fit the experimental data under experimental conditions. gEST, the parameter estimation tool in the gPROMS modeling package, was used to estimate the deactivation parameters. The parameter optimization solver named MXLKHD uses the

maximum-likelihood

approach

(Eq.14)

to

estimate

all

deactivation

parameters

simultaneously. This solver applies a sophisticated sequential quadratic programming (SQP) method to find the global optimum27.

= Φ

NE NVi NM ij ( y − y ) 2 N 1 ln(2π ) + min{∑∑ ∑ [ln(σ ijk2 ) + ijk 2 ijk ]} σ ijk 2 2 θ =i 1 =j 1 =k 1

(14)

The variance in the mole fraction of the components, with the exception of N2, was 0.001, whereas the variance in the mole fraction of N2 was 1000 to remove the effects of N2, which was used as a carrier gas, on the objective function in eq 14. 4. Results and discussion 4.1. Deactivation Experiments The reactor performance during around 86 h were obtained for test1-3 in Table 1, with varying temperatures ranging from 324.5 to 334.5oC. Figure 2 shows experimental data and model predictions with deactivation model DM3 for the 2,3-BDO conversion and selectivity of products at 324.5oC. During the reaction that was performed at 324.5oC, the 2,3-BDO conversion



shows a small decline while the selectivity for the reaction products remains unchanged over a period of 85.6 h, showing that the activity of the catalyst is nearly constant throughout the run.

1,3-BD

Predicted 1,3-BD

MEK

Predicted MEK

3B2OL

Predicted 3B2OL

2MPL

Predicted 2MPL

H2O

Predicted H2O

2,3-BDO Conversion

Predicted 2,3-BDO Conversion

120

100

80 2,3-BDO Conversion & Selectivity %

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60

40

20

0 0

10

20

30

40

50

60

70

80

90

time h

Figure 2. Experimental data and model predictions using deactivation model DM3 for the 2,3BDO conversion and selectivity of products at 324.5oC. When performing the same reaction at a temperature of 329.7oC, the 2,3-BDO conversion again shows a small decline but the most prominent feature is a dramatic increase in 3B2OL selectivity from 0.16 to 12.5% over a period of 85.6 h, while, at the same time the selectivity for 1,3-BD


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decreases from 32.2% to 22.3%, as seen in Figure 3. This is in stark contrast to the selectivities observed at 324.5oC; a direct comparison of the initial (at t = 1.6 h) selectivity for 1,3-BD at 324.5oC and 329.7oC, shows a selectivity of 18.6% to 32.2%, respectively. The increased 1,3-BD selectivity leads the deactivation of the catalyst that makes r2 slow. Eventually, the deactivation of the catalyst results in a continuous decrease of the selectivity for 1,3-BD and in an increase of the selectivity for 3B2OL.

1,3-BD

Predicted 1,3-BD

MEK

Predicted MEK

3B2OL

Predicted 3B2OL

2MPL

Predicted 2MPL

H2O

Predicted H2O

2,3-BDO Conversion


120

100


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60

40

20

0 0

10

20

30

40

50 time h


60

70

80

90


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Figure 3. Experimental data and model predictions using deactivation model DM3 for the 2,3BDO conversion and selectivity of products at 329.7oC. At 334.5oC, as shown in Figure 4, the selectivities for 1,3-BD and 3B2OL remain constant at 33.1% and 0%, respectively for a period of about 20 h. At a time of 21.6 h until a time of 53.6 h, the selectivity for 1,3-BD decreased linearly to 20.2% and at the same time, the selectivity for 3B2OL increased linearly to 16%. Both selectivities remain constant for the remaining reaction time. In the same reaction, the 2,3-BDO conversion maintains 100% until 33.6h and then declines to 88.1 continuously. The initial 1,3-BD selectivity at 334.5oC at 1.6 h is 32.7%, which is just 0.5% higher compared to the 1,3-BD selectivity at 329.7oC. The change in 1,3-BD selectivity at 334.5oC does not occur until a time of 21.6 h, due to an by 4.8oC increased reaction temperature. This causes the deactivation of the catalyst in a fashion that decreased not only r2 but also the 2,3-BDO conversion sharply. In all performed test reaction, the selectivities for MEK and 2MPL showed a flat pattern that indicated less dependence on the activity of the catalyst compared to the selectivities of 1,3-BD and 3B2OL. This in turn shows that the reaction route for the production of 1,3-BD highly depends on the deactivation of the a-CP catalyst while the other routes are less dependent on the deactivation of a-CP.


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1,3-BD

Predicted 1,3-BD

MEK

Predicted MEK

3B2OL

Predicted 3B2OL

2MPL

Predicted 2MPL

H2O

Predicted H2O

2,3-BDO Conversion


120

100


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60

40

20

0 0

10

20

30

40

50

60

70

80

90

time h

Figure 4. Experimental data and model predictions using deactivation model DM3 for the 2,3BDO conversion and selectivity of products at 334.5oC. Based on the experimental data above, the deactivation of a-CP can be explained by the following steps: (i) 1,3-BD selectivity is increased sharply as the temperature increases. (ii) The high 1,3-BD selectivity and temperature increase the possibility of 1,3-BD polymerization. 15 Environment ACS Paragon Plus


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(iii) Heavy compounds resulting from polymerization cover the active surface of the catalyst and block the pores of the catalyst 4.2. Assessment of deactivation parameters Table S3 in the Supporting Information shows objective function values and estimated deactivation parameters of DM1-3 mentioned in Section 3.2. The a-CP catalyst's deactivation cannot be expressed by using empirical functions (DM1-2) that relate the catalyst activity directly to time, because it would not be sufficient to predict the deactivation rate at any process time. The minimum value of the objective function is obtained for DM3. All deactivation parameters of DM3 can be considered significant since each standard deviation is very small compared to the parameter. As seen in Figures 2-4, the predicted values of 2,3-BDO conversion and product selectivity show good correlations with the experimental values although the predicted and experimental values of 2,3-BDO conversion and 1,3-BD and 3B2OL selectivity show a small difference. At 334.5oC, the best reactor performance for 2,3-BDO conversion and 1,3-BD selectivity was observed, where the predicted values of 1,3-BD and 3B2OL selectivity decreases and increases faster than the experimental ones, as seen in Figure 4. Therefore, a regeneration time of a-CP catalyst can be determined conservatively using the deactivation model DM3. The value of the deactivation order m and the limiting activity at infinite time α eq are found to be 1.32 and 0.33, respectively. The activation energy for the deactivation Ed is 1.00E+06 J/mol. GPLE can describe the a-CP catalyst's deactivation, because the catalyst activity would not decline to zero at large time as shown in Figure 4. 4.3. Regeneration


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A flow catalysis experiment was performed for 9.6 h after the regeneration of the a-CP catalyst used for test 3. Table 2 shows the average 2,3-BDO conversion and selectivity of products before and after the regeneration. The activity of the a-CP catalyst remains constant after the regeneration although the selectivity for 1,3-BD decreases and the selectivity for 3B2OL increases a small amount. This result shows that thermal pyrolysis does not cause the catalyst deactivation. Table 2. Averaged 2,3-BDO Conversion and Selectivity of Products for 9.6 h before and after the Regeneration 2,3-BDO Conversion and Selectivity of products

Unit

Before regeneration

After regeneration

2,3-BDO conversion

%

100

100

1,3-BD

%

33.14

32.96

MEK

%

31.64

31.80

3B2OL

%

0.00

0.06

2MPL

%

4.19

4.21

H2O

%

31.03

30.97

5. Conclusion A suitable deactivation model was developed for the dehydration of 2,3-BDO to 1,3-BD and MEK over an a-CP catalyst. The deactivation of the a-CP catalyst can be explained with the pathways of 2,3-BDO dehydration, the results of element analysis, and the reactor performance of the deactivation experiments. The deactivation of a-CP catalyst can be explained by the following steps: (i) 1,3-BD selectivity is increased sharply as the temperature increases. (ii) the high 1,3-BD selectivity and temperature raise a possibility of the polymerization of 1,3-BD. (iii)



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heavy compounds made by polymerization covers the active surface of the catalyst and blocks the pores of the catalyst. Three deactivation models (DM1-3) have been established to explain the deactivation of the a-CP catalyst. Among them, the simplified concentration-independent generalized power law expression (DM3) shows the minimum value of the objective function and all deactivation parameters of DM3 are considered significant because each standard deviation is very small compared to its parameter. The estimated values of DM3 are very well matched with the observed trend of the experimental results. The activation energy for deactivation Ed is 1.00E+06 J/mol. The value of the deactivation order m and the limiting activity at infinite time α eq are found to be 1.32 and0.33, respectively. The proposed deactivation model is novel as it characterizes the a-CP catalyst's deactivation. The activity of the a-CP catalyst remains unchanged after regeneration, which was determined by the same experiment as for the fresh a-CP catalyst.

Supporting Information The Supporting Information is available free of charge on the ACS Publications website. Kinetic Parameters, Result of Element Analysis, Objective Function Value and Estimated Deactivation Parameters of DM1-3 Nomenclature a

parameter to be estimated

b

parameter to be estimated


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C

mole concentration, mol/m3

CW

cumulative work done by the catalyst, mol/kg-cat s

E

activation energy, J/mol

Ed

activation energy for deactivation, J/mol

F

mass flow rate, g/s

Kd

deactivation rate constant, 1/s

Kd_ref deactivation pre-exponential factor, 1/s k

reaction rate constant, mol(1-n) m3(n-1) s-1

kTref

transformed Arrhenius kinetic constant, variable units

m

deactivation order

N

total number of measurements taken during all experiments

NE

number of experiments performed

NVi

number of variables measured in the ith experiment

NMij

number of measurements of the jth variable in the ith experiment

n

reaction order

P

pressure, Pa

R

ideal gas law constant, J/mol K



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r

reaction rate, mol/kg-cat s

S

mass selectivity, %

T

temperature, K

t

time, s

Tref

reference temperature, K

us

superficial fluid velocity, m/s

X

conversion, %

z

axial reactor coordinate, m

yijk

kth model-predicted value of variable j in experiment i

Greek Letters α

catalyst activity

α eq

limiting activity at infinite time

ÿijk

kth measured value of variable j in experiment i

ρb

bulk density of catalyst bed, kg/m3

ν ji

stoichiometric coefficient of species j in reaction i

Φ

objective function

θ

set of parameters to be estimated


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σ ijk2

variance of the kth measurement of variable j in experiment i

Subscripts i

reaction i

j

species j

react

reactant

rxn

reaction

References (1) Greiner, E.; Janshekar, H.; Kumamoto, T.; Zhang, E. Chemical Economics Handbook Methyl Ethyl Ketone(MEK); IHS Chemical, 2015. (2) Sriram, P.; Hyde, B.; Smith, K. Btadiene Chemical Economics Handbook; IHS Chemical, 2016. (3) Zheng, Q.; Wales, M. D.; Heidlage, M. G.; Rezac, M.; Wang, H.; Bossmann, S. H.; Hohn, K. L. Conversion of 2,3-butanediol to Butenes over Bifunctional Catalysts in a Single Reactor. J. Catal. 2015, 330, 222. (4) Winfield, M. E. The Catalytic Dehydration of 2,3-butanediol to Butadiene. J. Counc. Sci. Ind. Res. 1945, 18, 412. (5) Bourns, A. N.; Nicholls, R. V. V. The Catalytic Action of Aluminium Silicates: I. The Dehydration of Butanediol-2,3 and Butanone-2 over Activated Morden Bentonite. Can. J. Res. 1947, 25b, 80.



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(6) Winfield, M. E. The Catalytic Dehydration of 2,3-butanediol to Butadiene. II. Adsorption Equilibria. Aust. J. Sci. Res. A. 1950, 3, 290. (7) Kannan, S. V.; Pillai, C. N. Dehydration OF Meso-and DL-Hydrobenzoins and 2,3Butanediols over Alumina. Indian J. Chem. 1969, 7, 1164. (8) Molnár, Á.; Bucsi, I.; Bartók, M. Pinacol Rearrangement on Zeolites. Stud. Surf. Sci. Catal. 1988, 41, 203. (9) Bucsi, I.; Molnár, Á.; Bartók, M.; Olah, G. A. Transformation of 1,2-diols over Perfluorinated Resinsulfonic Acids (Nafion-H). Tetrahedron 1994, 50, 8195. (10) Török, B.; Bucsi, I.; Beregszászi, T.; Kapocsi, I. Transformation of Diols in the Presence of Heteropoly Acids under Homogeneous and Heterogeneous Conditions. J. Mol. Catal. A: Chem. 1996, 107, 305. (11) Lee, J.; Grutzner, J. B.; Walters, W. E.; Delgass, W. N. The Conversion of 2,3-butanediol to Methyl Ethyl Ketone over Zeolites. Stud. Surf. Sci. Catal. 2000, 130, 2603. (12) Daniell, J.; Köpke, M.; Simpson, S. D. Commercial Biomass Syngas Fermentation. Energies 2012, 5, 5372. (13) Zhang, W.; Yu, D.; Ji, X.; Huang, H. Efficient Dehydration of Bio-based 2,3-butanediol to Butanone over Boric Acid Modified HZSM-5 Zeolites. Green Chem. 2012, 14, 3441. (14) Han, Y.; Kim, H.; Hong, J.; Jho, H. Fabrication method of 1,3-butadiene and 2-butanone from 2,3-butanediol. K.R. Patent 10-1287167 B1, 2013. (15) Duan, H.; Sun, D.; Yamada, Y.; Sato, S. Dehydration of 2,3-butanediol into 3-buten-2-ol Catalyzed by ZrO2. Catal. Commun. 2014, 48, 1. (16) Kim, H.; Lee, H.; Park, D. Amorphous calcium phosphate catalyst used for 1,3-butadiene and methyl ethyl ketone from 2,3-butanediol and preparation method thereof. K.R. Patent 10-


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2014-0167303, 2014. (17) Makshina, E. V.; Dusselier, M.; Janssens, W.; Degrève, J.; Jacobs, P. A.; Sels, B. F. Review of Old Chemistry and New Catalytic Advances in the On-purpose Synthesis of Butadiene. Chem. Soc. Rev. 2014, 43, 7917. (18) Duan, H.; Yamada,Y.; Sato, S. Efficient Production of 1,3-butadiene in the Catalytic Dehydration of 2,3-butanediol. Appl. Catal., A. 2015, 491, 163. (19) Kim, T. Y.; Baek, J.; Song, C. K.; Yun , Y. S .; Park, D. S.; Kim, W.; Han, J. W.; Yi, J. Gasphase Dehydration of Vicinal Diols to Epoxides: Dehydrative Epoxidation over a Cs/SiO2 Catalyst. J. Catal.2015, 323, 85. (20) Duan, H.; Yamada, Y.; Sato, S. Future Prospect of the Production of 1,3-butadiene from Butanediols. Chem. Lett. 2016, 45, 1036. (21) Nikitina, M. A.; Ivanova, I. I. Conversion of 2,3-Butanediol over Phosphate Catalysts. ChemCatChem 2016, 8, 1346. (22) Tsukamoto, D.; Sakami, S.; Ito, M.; Yamada, K.; Yonehara, T. Production of Bio-based 1,3Butadiene by Highly Selective Dehydration of 2,3-Butanediol over SiO2-supported Cesium Dihydrogen Phosphate Catalyst. Chem. Lett. 2016, 45, 831. (23) Thome, A. G.; Ayral, N.; Toufar, H.; Klüner, T.; Roessner, F. Dehydration of 2,3-Butanediol: A Catalytical and Theoretical Approach. Catal. Lett. 2017, 147, 1 (24) Duan, H.; Yamada, Y.; Kubo, S.; Sato, S. Vapor-phase Catalytic Dehydration of 2,3Butanediol to 3-buten-2-ol over ZrO2 Modified with Alkaline Earth Metal Oxides. Appl. Catal., A.2017, 530, 66. (25) Song, D. Kinetic Model Development for Dehydration of 2,3-Butanediol to 1,3-Butadiene and Methyl Ethyl Ketone over an Amorphous Calcium Phosphate Catalyst. Ind. Eng. Chem. Res.



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2016, 55, 11664. (26) Song, D.; Yoon, Y. G.; Lee, C. J. Conceptual design for the recovery of 1,3-Butadiene and methyl ethyl ketone via a 2,3-Butanediol-dehydration process. Chem. Eng. Res. Des. 2017, 123, 268. (27) Process Systems Enterprise Ltd., gPROMS Advanced User Guide, 2004. (28) Gates, B. C.; Katzer, J. R.; Schuit, G. C. A. Chemisty of Catalytic Processes; McGraw-Hill: New York, 1979. (29) Forzatti, P.; Lietti, L. Catalyst Deactivation. Catal. Today. 1999, 52, 165. (30) Speybroeck, V.; Reyniers, M. F.; Marin, G. B. Modeling Elementary Reactions in Coke Formation From First Principles Pap-Am. Fuel Chem. 2001, 49, 781. (31) Voorhies, A. Carbon formation in catalytic cracking. Ind. Eng. Chem. Res. 1945, 37, 318. (32) Szepe, S.; Levenspiel, O. Proceedings of the Fourth Europrean Symposium on Chemical Reaction Engineering; Pergamon Press, Brussels, 1971. (33) Fuentes, G. A. Catalyst Deactivation and Steady-state Activity: A Generalized Power-law Equation Model. Appl. Catal.1985, 15, 33

Figure Captions Figure 1. Major (solid arrows) and minor (dashed arrows) pathways of 2,3-BDO dehydration (25) Figure 2. Experimental data and model predictions using deactivation model DM3 for the 2,3-BDO conversion and selectivity of products at 324.5oC. Figure 3. Experimental data and model predictions using deactivation model DM3 for the 2,3-BDO conversion and selectivity of products at 329.7oC. Figure 4. Experimental data and model predictions using deactivation model DM3 for the 2,3-BDO conversion and selectivity of products at 334.5oC.


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For Table of Contents Only 1,3-BD Predicted MEK 2MPL Predicted H2O

Predicted 1,3-BD 3B2OL Predicted 2MPL 2,3-BDO Conversion

MEK Predicted 3B2OL H2O Predicted 2,3-BDO Conversion

120

100

An amorphous calcium phosphate

2,3-BDO Conversion & Selectivity %

Page 25 of 25

80

60

40

20

0 0

10

20

30

40

50 time h


60

70

80

90

Development of a Deactivation Model for the Dehydration of 2,3

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