To convert glycerol to gasoline range molecules

Improve Octane number

 

Objectives & Approach

To deoxygenate biomass-derived compounds to fuel molecules that can be used as, or blended into, gasoline or diesel

To study the behavior of different metal catalysts on deoxygenation of biomass derived molecules

To study catalytic control of selectivity toward desired products that can be used as fuels or chemicals by investigating the control factors such as residence time, temperature and weight loading.

Use model compound 2-methyl -2-pentenal (produced from glycerol) that is typical of biomass derived molecules containing both C=C and C=O bonds

 

Experiment setup

Impregnation method

Metals: Pt, Pd, Cu

Support: Hisil 210 (silica), Sg =160-200 m2/g

Loading: 0.5%wt for Pt, Pd; 0.5 % and 5%wt for Cu

Dry overnight 100oC Calcine in air 400oC and reduced 400oC before test for activity

Operating conditions

Operating temp: 200oC, 1 bar Pressure H2 to feed molar ratio: 12:1

Product analysis: online GC & GCMS

 

Hydrogenation of C=C bond is dominant on Pt and Pd at 200oC

Hydrocarbon product is predominant at elevated temperatures

Hydrocarbon is pentane, which is one carbon less than the original chain length (because of decarbonylation)

Alcohol is the predominant product on Cu at 200oC

The C6 Hydrocarbon, 2-methyl-pentane, has highest yield at higher temperature (400oC)

 

Proposed mechanism

Ether formation on Pd

It’s desirable to build up the chain length (C12 – C18) via dimerization reactions. The products are in the range of diesel fuels.

Ether formation (C12 ether) is being studied and has some promising results

Conclusions

Overall activity Pt>Pd>Cu Pt and Pd shows decarbonylation to C5

Cu shows hydrogenolysis activity and high yield of alcohol at high W/F and C6 at elevated temperature

Product selectivity can be controlled by type of metal and operating conditions

Further reaction of aldehyde to form C12 ether may be viable on Pt or Pd catalysts

Maximizing longer branched chain of hydrocarbon or ether (C12 –C18) can be a good blending component for diesel fuel.