1a. Objectives (from AD-416):
The objective of FarmBio3 is twofold: (i) to leverage the existing synergies among partners to further research and optimize pyrolysis pathways to commodity fuels and chemicals and improve the TRL 4 status already achieved at ARS and (ii) increase to on-farm scale that will enable the current state of technology to, TRL 6, commercial status.
1b. Approach (from AD-416):
Will focus on three feedstocks that are important to U.S. agriculture including switchgrass, horse manure and woody biomass. The primary conversion platform will be catalytic and non-catalytic fast pyrolysis for production of stable fuel intermediates. Because barriers to utilization of such intermediates are high we will develop more robust multi-functional heterogeneous catalysts to balance deoxygenation pathways to minimize oxygenate production while increasing carbon efficiency for the selected feedstock pool. Bifunctional catalysts will be developed to upgrade and optimize carbon distribution in the condensed phase pyrolysate to achieve C6-C14 hydrocarbons and target entry to gasoline, diesel and jet range fuels markets. We will develop and optimize homogeneous catalysts to break C-O bonds of the lignin fraction of lignocellulosic pyrolysate to produce specialty chemicals. Pyrolysis process improvements will be integrated at on- the-farm scale using an existing patent-pending dual fluidized bed, combustion-reduction integrated pyrolysis, unit (CRIPS) designed to mimic the fluid catalytic cracking (FCC) process. Using real process data from this scale up and optimized upgrading, an exergetic LCA will be performed to describe not only economics and greenhouse gas emissions but also resource depletion and loss of quality for distributed on-farm thermolysis; this will be the first complete economic, environmental, and social sustainability analysis for on-farm pyrolysis.
3. Progress Report:
This is a sub-award for a NIFA funded Biomass Research & Development Initiative project (FarmBio3) for which ARS is the principal investigator. Using their established method of catalyst synthesis, collaborators at USC have optimized conditions for the deposition of ruthenium catalysts onto commercial supports. Synthesizing larger batches of catalyst at these optimal conditions led to ultra-small, highly dispersed ruthenium nanoparticles. The particles were too small to be detected by traditional x-ray diffraction techniques, but could be imaged by high resolution electron microscopy. The mean ruthenium nanoparticle diameter over carbon supports is 1.3 nm, while the diameter over alumina is 0.92 nm. In addition, USC synthesized ruthenium nanoparticles on silica, in order to examine the support effect with control samples. A comprehensive literature search conducted by another FarmBio3 partner, U.Delaware, suggested that single metal platinum catalysts may be more selective than single metal Ru catalysts. Based on this finding, USC also synthesized a set of platinum catalysts with carbon, alumina, and silica supports, parallel to the ruthenium catalysts. All catalysts have about the same metal content (1.3 – 2.2 wt%), and all have relatively small particle sizes. All six samples were sent to the University of Maine (another FarmBio3 partner) for reactivity evaluation with bio-oil model compounds. Eventually, this catalyst synthesis technique will be applied to supports synthesized by collaborators at Villanova, PA.