Biodiesel

Cost , Energy and Material Analysis of Biodiesel Production Using Homogeneous and Heterogeneous CatalystPrepared by: Nik Nor Azrizam Bin Nik Norizam Muhamad Hazim Bin Azemi 11609 (ID Number) 11605 (ID Number)

Introduction

Biodiesel definition

Product of the reaction of an alcohol (methanol or ethanol) with a animal fat or vegetable oil to form glycerol, mono-alkyl esters of fatty acids and excess methanol. Catalyst is used during the formation of biodiesel. Purpose of biodiesel production Promising alternative to conventional petroleum based diesel fuel. Answer to overcome global warming by reducing carbon dioxide and nitrogen dioxide gas emission.

Advantages of biodiesel

Derived from a renewable domestic resource (vegetable oil). Reduces carbon dioxide emissions by 78% compared to diesel fuel. Non-toxic and biodegradable. Environmental fuel. Methods to Produce Biodiesel a) Using supercritical methanol. b) Using fast and slow pyrolysis. c) Using catalyst.

Reason using catalyst method in biodiesel production

Convenient to use catalyst in small scale operation. Easy to conduct experiment in laboratories. More cheaper compare to other methods. No need additional equipment.

v

Overview

To compare biodiesel production using homogeneous and

heterogeneous catalysts. To study on how homogeneous and heterogeneous catalysts will affect on material, energy and cost for the process. To compare effectiveness of homogeneous and heterogeneous catalysts towards biodiesel production. All simulation and modeling are done using MATLAB software and it based on small scale batch mode process. 3 factors are being studied which are materials, energy and cost. They contribute the most in determining which catalyst is the best. To see effect of all three factors towards environment and business. All the factor can be related to each other.

Process Diagram for Both Homogeneous and Heterogeneous Catalysts ( Base Line )

Figure 1 : Homogeneous Catalyst Process Diagram

Figure 2 : Heterogeneous Catalyst Process Diagram

Equipment Modeling

Heat to raise temperature (Q raise) This heat is required to increase temperature of the system to operating temperature and is define as

Q raise = i C p m

i

(T f i) T

Heat Released by conduction or by convection (Q out conduction / Q out convection) This heat occurs when there is temperature different between equipment and surrounding.

Q out

convection

= [ h air Aequipment (T equipment T air )] total

time

Q out

conduction

= [k equipment A equipment

(T equipment T air ) ( x1 x 2 )

] total time

Heat of reaction (Q reaction) This heat occurs due to chemical reaction from two or more substances. There are two type heat of reaction which is exothermic and endothermic heat of reaction. Exothermic heat of reaction will release heat from the system to environment and for endothermic reaction will require heat for reaction to take place

Qrxn = H o @ 25C + H @T out f H o @ 25 C = (ni H o i ) product (ni H o i ) reactan t f f f H @T out= (ni C pi) prod(T T @ 25 C) (ni C pi) reactant (T T @ 25 C)

Heat to maintain temperature (Q maintains) This heat is required for the system to maintain its operating temperature for period of time until the process is done. For exothermic reaction

Q ma int ain =Q out Q ma int ain =Q out

convection / conduction

Q rxn +Q rxn

For endothermic reaction

convection / conduction

Heat Release by temperature drop (Q drop) This heat is due to cooling down substance before going to next process.

Q drop =m i C p i (T f T i)

HEATING TANK (PREHEATING PROCESS)

In p u t F e e d in Temp in itia l Temp fin al

O u tp u t Q

Feed out

M o d e l d i g ra m a Pro ce ss d i g ra m a

Calculation of Heat Required in Preheating Process

Q required Q requiredSymbol Q m veg oil Cp veg oil Tf Titotal

total

=Q raise Cpveg oil

=m veg

oil

(T f T i)

Definition Heat required (J) Mass vegetable oil enter (kg) Specific Heat Capacity (1670temperature system Final J/kg K) (333K) Initial temperature system (298 K)

OVEN ( CALCIUM CARBONATE DECOMPOSE PROCESS)

Heat Release by Conduction Heat Release by temperature drop

CaCO3Qrxn

Heat to maintain temperature

Heat to raise temperature

Pro ce ss d i g ra m a M o d e ld i g ra m a

Chemical Equation in Decompose Process

Calculation of Total Heat RequiredQ requiredQ requiredtotal

total

=Q raise +Q out

conduction

+Q reaction

= [n CaCO 3 C PCaCO3 ](T f T i) + [(k oven A oven + (H o @ 25C + H @T out ) f

(T ovenT air ) ) total time 6] ( x1 x 2 )

where

H @T out = [ n CaO Cp CaO +n CO 2 Cp CO 2 n CaCO 3 Cp CaCO 3 ] (T out T @ 25 C)

(

) (

)

Symbol k oven A oven T oven T air Total time (x1 x2) H f @ 25 Tf Ti

Definition Thermal conductivity of cotton (0.03 W/m K) Surface area of oven (m2) Temperature inside oven (1073 K) Ambient temperature (308 K) Time required for process (10800 s) Oven thickness (0.22m) Enthalpy formation at 25 C Final temperature (1073 K) Initial temperature (308 K)

Calculation of Total Heat WastedQ wastedQ wastedtotal

total

= (Q out

conduction

total time ) +Q drop

= [k ovenA oven

(T ovenT air) total time 6] + n CaOC p CaO (T f T i) ( x1 x 2 )Definition Thermal conductivity of cotton (0.03 W/m K) Surface area of oven (m2) Temperature inside oven (1073K) Ambient temperature (308K) Time required for process (10800 s) Oven thickness (0.22 m) Final temperature (1073 K) Initial temperature (308 K)

Symbol k oven A oven T oven T air Total time (x1 x2) Tf Ti

MIXER TANK (MIXING PROCESS)

Pro ce ss d i g ra m a

M o d e ld i g ra m a

Chemical Equation in Mixing ProcessFor Homogeneous Catalyst

Potassium hydroxide

Methanol

Potassium methoxide

Water

For Heterogeneous Catalyst

Calcium Oxide

Methanol

Calcium methoxide

Calcium hydroxide

Calculation of heat in mixer: 1 For homogeneous catalyst (endothermic)Heat released total Heat required total

1 For heterogeneous catalyst (exothermic)Heat released total Heat required total

Calculation for Heat Wasted from Mixer for Homogeneous and Heterogeneous Catalyst

-

Heat release from mixer using homogeneous and heterogeneous is the same using convection mode.Q wastedtotal

= [[h air Amixer (T mixer T air )] total

time ]

Symbol Q wasted total h air A mixer T mixer T air Total Time

Definition Heat released by system (J) Heat transfer coefficient (50 W/m2 K) Area of mixer (m2) Temperature mixer (333 K) Temperature air (308 K) Total Time for mixing process (1800 s)

Calculation of Total Heat Required for Homogeneous Catalyst- Since the reaction of methanol and potassium hydroxide is endothermic, we must add heat of reaction in heat required total calculation.

Q required

total

=Q raise +Q ma int ain

Q required

total

=Q raise +Q out

convection

+Q reaction

whereSymbols

H @T out= [ n K (CH 3)O CpK (CH 3)O + n H 2O CpH 2O n CH 3OH CpCH 3OH + n KOH CpKOH ] (T outT @ 25 C)Definition Specific heat capacity of methanol (86.2 J/mol K) Specific heat capacity of potassium hydroxide ( 49.4626 J/mol K) Temperature final of system (333 K) Ti Temperature initial of system (308 K) Standard enthalpy formation of product at 25 C (J/mol) Heat transfer coefficient of air (50W/m2 K) Area of mixer (m2) Temperature mixer (333 K) Temperature air (308 K) Total Time for mixing process (1800 s)

(

) (

)

Cp CH3OH Cp KOH Tf H f @25 C h air A mixer T mixer T air Time

Calculation of Total Heat Required for Heterogeneous Catalyst- Since the reaction of methanol and calcium oxide is exothermic, we can use the heat release by the reaction process as heat to maintain system temperature.

Q required Q requiredtotal

total

=Q raise +Q ma int ainconvection

=Q raise +Q out

Q reaction

Q requiredwhere

total

= [n CH 3OH C P CH 3OH + n KOH C P KOH ](T f T i) + [h air Amixer (T mixerT air)] time (H o @ 25C + H @T out ) f

H @T out= [ n Ca(OCH3) 2 CpCa(OCH3) 2 + n Ca(OH ) 2 CpCa(OH ) 2 n CH 3OH CpCH 3OH + n CaO CpCaO ] (T outT @ 25 C)Symbols Cp CH3OH Cp CaO Tf Ti H f @25 C h air A mixer T mixer T air Time Definition Specific heat capacity of methanol (86.2 J/mol K) Specific heat capacity of Calcium Carbonate (44.1036 J/mol K) Temperature final of system (333K) Temperature initial of system (308K) Standard enthalpy formation of product at 25 C (J) Heat transfer coefficient of air (50W/m2 K) Area of mixer (m2) Temperature mixer (333K) Temperature air (308K) Total Time for mixing process (1800 s)

(

) (

)

BATCH REACTOR (TRANSESTERIFICATION PROCESS)Process diagram

Model diagram

Chemical Equation for Transesterification ProcessC h e m i l e q u a ti n u si g h o m o g e n e o u s ca ta l ca o n yst ( exothermic )Biodies el Excess Methanol

Feedstoc k

Methanol

C h e m i l e q u a ti n u si g h e te ro g e n e o u s ca ta l ca o n yst ( exothermic )Feedstoc k Methanol Biodies el Excess Methanol

Calculation of Heat Wasted for Homogeneous and Heterogeneous Catalyst

- Heat release from reactor using homogeneous and heterogeneous is the same using convection mode.

Q wasted

total

= [[h air Areactor (T reactorT air)] total time]Definition Heat released by system (J) Heat transfer coefficient (50 W/m2 K) (m2) Area of mixer Temperature reactor (333 K) Temperature air (308 K) Total Time for mixing process (3600 s)

Symbol Q wasted total h air A reactor T reactor T air Total Time

Calculation of Total Heat Required for Homogeneous and Heterogeneous Catalyst- Since the reaction for potassium hydroxide and calcium oxide with vegetable oil is exothermic, thus calculation of heat required total is :

Q required Q required

total

= ma int Q

ain

total

=Q out

convection

Q reaction

Q requiredWhere,

= [ h air Areactor(T reactorT air) total time] [ H o @ 25 C + H @T out] total f

[( n

H @ T = ( n glycerol C Pveg oil

[

CP

veg oil

) + (n

glycerol

) + (n

FAME

CP

FAME

) + (n excess

initial MeOH

CP

initial MeOH

) reac tan t (T T @ 25C )

]

MeoH

CP

excess MeOH

)

]

prod

(T T @ 25C )

( 6)

Symbols H f @ 25 C H @ T out h air A reactor T reactor T air Total time

Definition Standard enthalpy formation of product at 25 C (J) Enthalpy of formation of product at operating temperature (J) Heat transfer coefficient of air (50 W/m2 K) Area of reactor (m2) Temperature reactor (333 K) Temperature air (308 K) Total Time for mixing process (3600 s)

GRAVITY SETTLER (GLYCEROL SEPARATION PROCESS)Process diagram for homogeneous catalyst Process diagram for heterogeneous catalyst

Model diagram for homogeneous catalyst

Model diagram for heterogeneous catalyst

Calculation of Heat Wasted for Homogeneous and Heterogeneous Catalyst Q wasted total =Q drop subs tan ce For homogeneousQ wasted Q w asted total= (n M eO HC pSymbol n MeOH Cp MeOH n FAME Cp FAME n gly Cp gly n KOH Cp KOH Tf Titotal

=Q MeOH +Q FAME +Q Glycerol +Q KOH ) + (n F A M EC pFAM E

[

M eO H

) + (n gly C p

gly

) + (n K O H C p

KOH

) (T f T i )

]

Definition Mol of methanol (mol) Specific heat capacity methanol (86.2 J/mol K) Mol of FAME(mol) Specific heat capacity FAME (1.274 J/mol K) Mol of glycerol(mol) Specific heat capacity glycerol ( 229. 3 J/mol K) Mol of potassium hydroxide (mol) Specific heat capacity potassium hydroxide (49.4626 J/kg K) Final temperature system (308K) Initial temperature system ( 333 K)

For heterogeneous catalyst

Q wastedtotal

total

=Q drop

subs tan ce

Q wasted

=Q MeOH +Q FAME +Q Glycerol

Q wastedSymbol m MeOH

total

= (n MeOHC p

[

M eOH

) + (n FAM EC p

FAM E

) + (n gly C p

gly

) (T f T i)

]

Definition Mass of methanol (mol) Specific heat capacity methanol (86.2 J/mol K) Mol of FAME (mol) Specific heat capacity FAME (J/mol K) Mol of glycerol (mol) Specific heat capacity glycerol(229.3 J/mol K) Final temperature system (308K) Initial temperature system (333K)

Cp MeOH m FAME Cp FAME m gly Cp gly Tf Ti

HEATING TANK (METHANOL REMOVAL PROCESS)

Process diagram for homogeneous catalyst

Process diagram for heterogeneous catalyst

Model diagram for heterogeneous catalyst

Model diagram for homogeneous catalyst

Calculation of Total Energy Required for Homogeneous and Heterogeneous Catalyst

Q required

total

=Q raise

1

+Q vaporizati on

methanol

+Q raise

3

Calculation of Energy Required for Homogeneous and Heterogeneous CatalystQ requiredtotal

=n MeOH C p MeOH (T f 1T i1) +n MeOH H vaporizati on+n MeOH C p MeOH (T f 2T i 2)

Symbol n MeOH Cp MeOH Tf 1 Ti 1 n MeOH H vaporization Tf 2 Ti 2

Definition Mol of methanol (mol) Specific heat capacity methanol (86.2 temperature process 1 Final J/mol K) (308 K) Initial temperature process 1 (338) Mol methanol (mol) Enthalpy of vaporization methanol (35.3 kJ/mol) 2 Final temperature process (353 K) Initial temperature process 2 ( 338 K)

PURIFICATION TANK (POTASSIUM HYDROXIDE PURIFICATION PROCESS)

Process Diagram

Model Diagram

Calculation for Amount of Water Needed

Calculation of Final Temperature of Productm H 2O C pSymbol m H2O Cp H2O Tf Ti H2O m mix Cp mix Ti mixH 2O

(T f T i

H 2O

) =m mix C p

mix

(Ti

mix

T f )

Definition mass of water (g) Specific heat capacity of water (4.1813temperature FAME with Final J/g K) water (K) Initial temperature H2O (308 K) Mass of FAME with KOH (g) Specific heat capacity of FAME with KOH (J/g K) of FAME Initial temperature with KOH (353 K)

DRYER (MOISTURE REMOVAL PROCESS)Process diagram

Model diagram

Calculation of Heat Required for Homogeneous Catalyst

Q required

total

=Q raise 1+Q vaporizati on

water

+Q raise

3

Q required

total

= n H 2O C p H 2O (T f 1T i1) + n H 2O H vaporization+ n H 2O C p H 2O (T f 2T i 2)

Symbol n water Cp water Tf 1 Ti 1 H vaporization Tf 2 Ti 2

Definition mol of water (mol) Specificheat capacity of water (75.327temperature process 1 Final J/mol K) (373 K) Initial temperature process 1 (from Tf purification process) Enthalpy of vaporization of water temperature process 2 Final (40.65 kJ/mol) (393 K) Initial temperature process 2 (373 K)

Parameter selection

Catalyst Mass of vegetable oil enter system Mass of methanol recover Surface area of mixer Surface area of reactor Temperature enter preheating process Temperature leave preheating process Temperature enter mixing process Temperature leave mixing process Temperature enter transesterification process Temperature leave transesterification process Temperature enter separation process Temperature leave separation process Temperature enter removal process Temperature leave removal process Temperature of mixture ( FAME + KOH ) enter purification process Temperature leave drying process Weight percentage of methanol in FAME Fraction of water in FAME Solubility of KOH in water Temperature of heat recovered leave Temperature of heat recovered enter Temperature of water

Homogeneous 90 kg 0 kg 0.0628319 m2 0.6126106 m2 35 C 60 C 35 C 60 C 60 C 60 C 60 C 35 C 35 C 80 C 35 C 120 C 60 % 0.01 1.21 kg/L 35 C 80 C 35 C

Heterogeneous 90 kg 0 kg 0.1099557 m2 0.6283185 m2 35 C 60 C 35 C 60 C 60 C 60 C 60 C 35 C 35 C 80 C 60 % 1.5707963 m2 35 C 80 C 35 C

Area of pipe for heat recovered from methanol removal 0.7539822 m2

Mass of CaO recover from filtration process Thermal conductivity of oven Thickness wall of oven Area of oven Temperature enter decompose process Temperature outside oven Temperature inside oven Decomposition time

-

0 0.03 0.22 0.1275 m2 35 C 35 C 800 C 10800 s / 3 hours

Table 1 : Parameter Selection

Table 2 : List of Chemical Price

Simulation Result & Discussion for One Batch ( Base Line )

Heterogeneous

Homogeneous

Heterogeneous

Homogeneous Heat Wasted

He ter oge neo us Hea t Wa ste d

Homogeneous

Heterogeneous

Simulation Result & Discussion for Multiple Batches ( Base Line )

Process Diagram for Both Homogeneous and Heterogeneous Catalysts ( Case 1 - Heat Recovered from Methanol Recycle Stream )

Figure 3 : Homogeneous Catalyst Process Diagram with Heat Recovered

Figure 4 : Heterogeneous Catalyst Process Diagram with Heat Recovered

Equipment Modeling For Case 1

HEAT RECOVERED PROCESSProcess DiagramHeat out from methanol vapor

Hot methanol

Cold water

Heat in to cold water

MeOH recovered Area pipe hot MeOH Final Temp MeOH Vapor MeOH temperature Water temperature Time

Heat Recovered

Model Diagram

Physical Diagram for Heat Recovered Process

Assumptions use : -Heat release by methanol occur by convection mode only. -We dont take into account heat release by conduction mode. -Total Heat loss from methanol will be absorb by water. -No heat loss from water to environment. -We assume temperature of final methanol after heat recovered is 35 C (liquid form).

Calculation of Heat Wasted from Methanol Stream

Q methanol

released

= Q drop 1+ Q condensation

methanol

+ Q drop

3

Q methanol

released

= n MeOH C p MeOH (T f T i) + n MeOH H vaporization+ n MeOH C p MeOH (T f T i)

Since, we specify final temperature of methanol after recovered process, thus we simplify how long for hot methanol must be in contact with water so that our final temperature that we want can be achieve. Thus,

Qmethanol

release

=Q absorb

water

Thus,n M eOHC p M eOH (T f T i) + n MeOH H condensati + n M eOHC p M eOH (T f T i) = h H 2O AM eOH onSymbol H condensation of methanol T MeOH T water h h2O A MeOH pipe Definition Enthalpy of condensation of methanol (35.3 kJ/mol) Temperature methanol from methanol removal process (353K) Initial water temperature (308 K) Heat transfer coefficient of water 5000 W/m2 K Area of pipe that carry hot methanol (m2)pipe

(T water T M eOH) total time

Simulation Result & Discussion for Multiple Batches ( Case 1 Heat Recovered from Methanol Recycle Stream )

Sensitivity Analysis

Graph Total Cost ( after 16 Batches with 90 kg of vegetable oil ) VS Price of KOH / CaCO3 ( fixed CaCO3 price = 900 Baht / kg )

Graph Total Cost ( after 16 Batches with 90 kg of vegetable oil ) VS Price of Water / MeOH ( fixed MeOH price = 184 Baht / L )

Conclusion & Recommendation

1. 2. Both homogeneous and heterogeneous catalysts have their own advantage and disadvantage. 3. Even heterogeneous catalyst can be reused until 13 times, it still required more cost than homogeneous catalyst. 4. From our project, we conclude that homogeneous catalyst is better than heterogeneous catalyst at certain conditions. 5. Using sodium methoxide catalyst for this biodiesel production can lead towards better or clear phase separation between FAME, glycerol and excess methanol. 6. For further improvement towards the biodiesel production process, heat recovered from methanol can be apply to purification process.

References

1. 2. 3. Alex H. West, Dusko Posarac and Naoko Ellis. (2007). Simulation, Case Studies and Optimization of a Biodiesel Process with a Solid Acid Catalyst. INTERNATIONAL JOURNAL OF CHEMICAL REACTOR ENGINEERING, Vol. 5 (2007), Article A37, 1-8. 4. Alex H. West, Dusko Posarac and Naoko Ellis. (2008). Assessment of four biodiesel production processes using HYSYS. Plant. Bioresource Technology, 99 (2008), 6587-6601. 5. Y. Zhang, M.A. Dube, D.D. Mc Lean, M. Kates. (2003). Biodiesel production from waste cooking oil: 1. Process design and technological assessment. Bioresource Technology, 90 (2003), 1-16. 6. Y. Zhang, M.A. Dube, D.D. Mc Lean, M. Kates. (2003). Biodiesel production from waste cooking oil: 2. Economic assessment and sensitivity analysis. Bioresource Technology, 90 (2003), 229-240.

5. 6. J.M. Marchetti, V.U. Miguel, A.F. Errazu. (2008). Technoeconomic study of different alternatives for biodiesel production. FUEL PROCESSING TECHNOLOGY, 89 (2008), 740-748. 8. Tsutomu Sakai, Ayato Kawashima, Tetsuya Koshikawa. (2009). Economic assessment of batch biodiesel production processes using homogeneous and heterogeneous alkali catalysts. Bioresource Technology, 100 (2009), 32683276. 9. Albert J. Gotch, Aaron J. Reeder, and Aleesha McCormick. (2008). STUDY OF HETEROGENEOUS BASE CATALAYSTS FOR BIODIESEL PRODUCTION. Journal of Undergraduate Chemistry Research, 4, 58-62.

Q & A

Thank You Kap Kun Krub Terima Kasih