Biotechnology for Reduction and Conversion of Carbon Dioxide by jdx40246

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									Biotechnology for Reduction an
 Conversion of Carbon Dioxide


                     Ping Wang

 Department of Bioproducts and Biosystems Engineering
                Biotechnology Institute
                University of Minnesota




                   October 25, 2008
Why Biofuels
 Need of alternative transportation
  fuels
 Reduce CO2 emission and net
  accumulation in air
Changes in the concentration of CO2
over time in the Earth's atmosphere




                Source: University of Michigan, Lectures for Global Change
Changes in the Earth's surface
temperature for the last 140 years




                 Source: University of Michigan, Lectures for Global Change
Sea level rise due to Greenland ice
loss




              Source: Rignot and Kanagaratnam, Science, 2006, 311, 5763, 986 - 990
 What if CO2 emissions were reduced
Aim: CO2 reduction: 15% by 2015; 30 by 2020; 80% by 2050




                         Source: http://climatechange.sea.ca/bibliography.html#b45
Currently available CO2 emission
reduce approaches
 Buried underground or in ocean

 Land-fill

 Biomass-photosynthesis

 Substrate

 Solvent
Carbon Cycle with Biofuel
                          Atmospheric
                             CO2




                                        Fuel use CH3CH2OH+3/2O2
                                               → 2CO2+2H2O
         Photosynthesis
           CO2+H2O
         →O2+Biomass




                                                               Synethsis
                                                            hydrocarbon and
                             Bioethanol                      their products
                             CH3CH2OH
First Generation Biofuel: Corn-
Starch Bioethanol
Second Generation Biofuels
 Non-food Cellulosic and lignocellulosic
  biomass
 Diversified products: hydrogen,
  methanol, DME, etc.

 Not only need alternative resources,
  but also diverse products that can
  afford efficient processing
Also need second generation
production technologies




                       (Vessia et al., 2005)
The Wet Approach: a dream that
has yet to take the chance
Cellulosic ethanol is still challenging

 Recalcitrance of biomass
  to hydrolysis
 Cellulase is not cheap
  enough yet
 Lignin issue
  Carbon Efficiency of Bioethanol – Is
  this an ideal solution?
                hydrolysis       Fermentation     Purification

Biomass: 100%     50%        35%                 23%      20%
                  Eff.                                           Ethanol
Sugar: 70%
                         waste                  CO2

  Energy return: 10~0.6: 1, from methane,
   implying additional 1.5 carbon emission for
   each C in ethanol (assumeing 1:1 E return)
  Fresh water: Currently consumes 5 gallons
   of fresh water for each gallon of ethanol
The Dry Route: Cellulose
Gasification Reactions
                                                      △H (kJ/g-mol)
  Reaction                Stoichiometry                  (T=300K)
Pyrolysis      C6H10O5  5CO + 5H2 + C                      180
               C6H10O5  5CO + CH4 + 3H2                    300
               C6H10O5  3CO + CO2 + 2CH4 + H2             -142
Partial        C6H10O5 + ½ O2  6CO + 5H2                   71
oxidation      C6H10O5 + O2  5CO + CO2 + 5H2              -213
               C6H10O5 + 2O2  3CO + 3CO2 + 5H2            -778
Steam          C6H10O5 + H2O  6CO + 6H2                    310
gasification   C6H10O5 + 3H2O  4CO + 2CO2 + 8H2            230
               C6H10O5 + 7H2O  6CO2 + 12H2                 64

                                                  (Huber et al. 2006)
Biomass possess a low H/C ratio
for chemical synthesis of methanol

 Ethanol production from syngas is yet to be developed

Methanol production through chemical synthesis:


  CO + 2H2  CH3OH                            DH298K = -21.7 kcal/mol
  CO2 + 3H2  CH3OH + H2O                     DH298K = -9.8 kcal/mol




                           Table -Cellulose Gasification Reactions (Huber et al. 2006)
Methanol




 Both methanol and DME can be applied
  to current engine/gas station system
 Methanol can be used as an intermediate for other chemicals
 Toxicity? 15-min exposure in gas station < 0.7 L of diet soda

       Olah et al, Beyond Oil and Gas: The methanol Economy, 2006
Biomethanol is still challenging

 Not a cheaper process at this stage:
  need energy for gasification and
  synthesis

 Low carbon efficiency: Biomass has a
  H/C ratio of 1.8; 45% carbon
  efficiency at most
A third Generation of biofuels?
-Fuel production from CO2?

              Sequestration
                                CO2


             Photosynthesis
                                        Fuel use
                Biomass



                  Burning                            Synthesis
      Heat                                         hydrocarbon and
                                                    their products
                CO2                     CH3OH

                            Enzyme
                            Biotrans.
Recuction and Conversion of CO2 is
energy-demanding; yet doable via
various chemical routes
 Thermochemical with hydrogen
 Electrochemicall with water
 Biologically or biochemically with
  solar energy and water
Route of Biosynthesis of Biomethanol:
reversed biological pathway


        FateDH           FDH          ADH
  CO2            HCOOH         CH2O            CH3OH
    NADH NAD+       NADH   NAD+   NADH NAD+
          FateDH: Formate Dehydrogenase
          FDH:    Formaldehyde Dehydrogenase
          ADH:    Alcohol Dehydrogenase
          GDH:    Glutamate Dehydrogenase
          NAD(H): Cofactor
                 Feasibility: Theoretical Equilibrium
                 Constants

                  CO + 2H2  CH3OH
Thermochemical




                  DH298K = 8.5 kcal/mol, DG298K = 20.7 kcal/mol

                  CO2 + 3H2  CH3OH + H2O
                  DH298K = 7.8 kcal/mol , DG298K = 25.4 kcal/mol



                  CO2+ 3NADH + 3H+  CH3OH +3NAD+ +H2O
Biochemical




                  DG298K = - 22.58 kcal/mol

                   Ko= 3.57 E16
Multienzymic Catalysis Within
Nanopores
Reduction of Pyruvate Coupled with
NADH Regeneration
 Effective Shuttling of NADH within the
 nanopores
                              1.2
     Pyrvuvate/Glucose conc



                               1
                                                              Glucose
                              0.8
              (mM)




                              0.6
                              0.4                              Pyruvate
                              0.2
                               0
                                    0   2          4          6           8
                                              Time (days)


The addition of pyruvate led to the formation of NAD+ which
initiates the oxidation of glucose.

                                            El-Zahab et al, Biotechnol Bioeng. 2004
Another Solution: Nanoparticles afford mobility
and high enzyme activity

                               A                                    B




                            200 nm                                1 m



    PS nanoparticles prepared via emulsion polymerization
          Jia et al., Biotechnology and Bioengineering. 84:406-414, 2003 .
Collision Theory
Mobility of nanoparticles drive reaction
kinetics




                 Jia, Zhu and Wang, Biotechnol. Bioeng., 84: 406, 2003.
NAD+   Substrate A Substrate B



                   PRODUCT II

                                 Enzyme II




                         NAD+




        NADH
                PRODUCT I


                                 Enzyme I
Methanol production with cofactor regeneration

                                                       25

    CO2
                                                       20
                                                                 Immobil. enz. & free
                                                                 cofactor




                                       [MeOH] (  M)
                                                       15
          2
                        MeOH   6                       10


                                                       5

                                                                                Immobil. system
                                                       0
                    4
                                                            0   100    200         300     400   500
1             3                5
                                                                             [NADH] (M)



                  Reaction time: 30 min. T= 298K, pH=7, I=225mM

                                   El-Zahab et al., Biotechnology Bioeng., 2007.
           Reusability of the Immobilized
           System
                                            140
Cumulative Percentage-Yield of Methanol .




                                            120


                                            100                                                            ◊System w regeneration
                                             80                                                            □System w/o regeneration
                                             60                                                            ∆ Free cofactor system
                                             40


                                             20                                                            Reaction time: 30 min.
                                              0
                                                                                                           T= 298K, pH=7, I=225mM
                                                  0   1   2   3   4    5    6     7      8   9   10   11

                                                              Number of Reusing Cycles
Artificial Cells for
multienzyme biocatalysis




 Wang et al, China Particuology, 3: 304, 2005.
Encapsulated Nanoparticles




             Wang et al, China Particuology, 3: 304, 2005.
Motion of encapsulated
nanoparticles
Methanol life cycle

                               Sequestrated
                Natural Gas    CO2

 Wood/crops                                   Municipal
                                              Solid Waste

                     Methanol

 Alcohol Fuel                            Biodiesel
                     Other Chemicals
                     i.e. DME
                     Polymers
                     Alkanes
10,000 Kilometer Scale Problem
Nanobiotech Group at UMN
Acknowledgements
 Financial Supports
     IREE Seed Grant
     NSF CAREER Award
     USDA
 Lab members:
     Xueyan Zhao              Ben Frigo
     Ravi Narayanan           Fei Gao
     Songtao Wu,              Jim Hancock
 Collaborators:
     Dr. Jungbae Kim (Pacific Northwest National
  Lab)
     Dr. Guanghui Ma (Chinese Academy of Sciences)
     Dr. Michael Flickinger (UMN, Now NCSU)

								
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