Final Goals: Achieve a catalyst life longer than reactivation time
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Transcript of Final Goals: Achieve a catalyst life longer than reactivation time
Optimizing the Catalytic Cycle for the Dehydration of Biobased Glycerol to Economically Viable C3 Compounds.
Luke Richardson*, Jeffrey Seay*, *Department of Chemical and Materials Engineering, University of Kentucky, Paducah, Kentucky, 42002
First International Congress on Sustainability Science and Engineering, Cincinnati, Ohio, August 2009
Final Goals:Achieve a catalyst life longer than reactivation timeDesign a procedure for de-coking the catalyst in placeDevelop a process to regenerate the catalyst support in placeDesign a process to convert the coke into synthesis gas Optimize total carbon utilization of the process
Research Abstract:The catalyst used for this process is currently not economically viable due to carbon build up on the carrier surface. The hypothesis is that the catalyst was too active and was causing the reaction to occur too quickly. This caused solid carbon to build up on the catalyst carrier surface. In order to increase the life of the catalyst we hypothesized that a less active catalyst would slow the reaction and increase the life and productivity of the system, while not adversely affecting the viability of the process. The previous research used an active (H3PO4) catalyst and we will try a less active (NaH2PO4) catalyst.
Before After(90 min)
Experimental System
Initial Research Goal:The solid carbon that fouls the catalyst surface dramatically reduces its useful life.
However, there is an equilibrium relationship between steam, solid carbon, carbon monoxide and carbon dioxide.
2H2 + O2 → 2H20
2C + O2 → 2COC + O2 → CO2These equilibrium equations show that we
should be able to reactivate the used catalyst in place while also generating synthesis gas.
If this can be done in less time than the catalyst life then two reactors can be used to achieve a semi-continuous process that produces the desired product and synthesis gas.
1,2-Propanediol
Glycerol Hydroxyacetone
3-Hydroxypropionaldehyde
1,3-Propanediol Acrolein
Allyl AlcoholPropionaldehyde Acrylic Acid
FormaldehydeAcetaldehyde
+
- H2O
- H2O
- H2O- H2
- H2
+ H2+ O2+ H2
C3H4O2 C3H6OC3H6O
C3H4O CH2OC2H4OC3H8O2
C3H8O3 C3H6O2
C3H6O2 C3H8O2
Nitrogen
Reactor A
Reactor B
Glycerol
Oxygen
Catalyst Solution
Continuous Cycle System
Reactor
Glycerol BoilerNitrogen Heater
The Glycerol Reaction Tree
References:Levenspiel, Octave. Chemical Reaction Engineering. 3rd ed. USA, John Wiley & Sons. 1999.Smith, J.M. and Van Ness H.C. Introduction To Chemical Engineering Thermodynamics. Fourth Edition. Milan, McGraw-Hill,
Inc. 1987.Jernigan, R.J., Hansrote, S.A., Ramey, K., Richardson, L.E. and Seay, J.R. (2009): “Developing Sustainable Chemical Processes to
Utilize Waste Crude Glycerol from Biodiesel Production”, Design for Energy and the Environment, Proceedings of the Seventh International Conference on the Foundations of Computer-Aided Process Design, CRC Press, New York, New York, pp. 361 –370.
Seay J.R., Eden M.R. (2009): “Incorporating Environmental Impact Assessment into Conceptual Process Design”, Journal of Environmental Progress and Sustainability, Published Online: Dec 10 2008, DOI: 10.1002/ep.10328.