The University of Kentucky Center for Applied Energy Research has again made funding available to provide seed grant opportunities to CAER researchers to collaborate in exploring new energy-related ideas and to open up new avenues of research. This program, the "brainchild" of Directory Rodney Andrews, was established to bridge the divide between internal creative ideas and large government grants and/or industrial funding, with the objective being to develop a process of converting new research concepts into competitive proposals. The success of this program since its inception is obvious with 3 papers written; 4 proposals written and all 4 proposals funded for a total of nearly $800,00.00 of external funding!     For the second year, the CAER Staff gathered to hear presentations given by 8 different young scientists that received a "seed" grant during 2014.

 

Leland Widger - Presenter - Catalytic Hydrogenation of Carbon-Loaded Amine Solutions for CO2 Capture and Utilization (co-authors Cameron Lippert): Much effort in recent research has focused on the direct activation of CO2 by hydrogenation catalysts for reduction by molecular H2 to methanol. However, the direct activation of gaseous CO2 and the subsequent reduction by 3 reducing equivalents is a difficult and energy-intensive transformation. We proposed to combine the advantages of amine-based CCS, the activation of CO2 by aqueous amines, with the utility of reduction catalysts to obtain an accessible and valuable chemical feedstock, formic acid. Hydrogenation by a single reducing equivalent would be more atom-efficient than methanol production, but the feasibility of direct reduction of carbamate in aqueous solution needed to be evaluated.

 

Bob Jewell - Presenter - Evaluation of Pure Ettringite/MWCNT Array Layered Composite for Piezoelectric Effect - (co-authors Anne Oberlink and Ashley Morris): The overarching objective of this research is to functionalize calcium sulfoaluminate (CSA) cements for energy harvesting and as a smart-sensing construction material. The discovery and characterization of ettringite, the primary strength contributor in CSA cement, as a piezoelectric crystal phase will create new knowledge on energy harvesting from CSA cement materials. The data on material properties and piezoelectric potential of ettringite-rich cementitious structural elements will not only enable the functionalization of construction materials as energy harvesting components but also will lay a solid foundation for future piezoelectric cementitious design. This project was awarded a National Science Foundation Grant for $309,737; which was directly related to the results from the CAER Seed Research Grant.

 

Nick Holubowitch - Presenter - Scavenging Waste Heat with Carbon Nanotubes in Thermelectrochemical Cells - (co-authors Cameron Lippert, James Landon): The work investigated the conversion of waste heat, a ubiquitous form of currently untapped energy, to electricity, a usable, concentrated form, using thermoelectrochemical cells. The Carbon group provided low-cost spray coated carbon nanotube (CNT) electrodes which were subjected to a variety of optimizations in our custom built device for thermal energy scavenging. We constructed a cell capable of delivering a mass activity of 290 W kg-1 CNTs by only using 0.08 mg cm-2 (<$0.01 per cell) of this normally cost-prohibitive material. The findings should be of broader interest to myriad energy storage and conversion technologies seeking to exploit the attractive properties of carbon nanotubes. The seed funding led to a full grant ($94,000) from the Kentucky Department for Energy Development and Independence.

 

Eduardo Santillan-Jimenez - Presenter - Carbon-supported Molybdenum Carbide Catalysts for Bio-oil Hydrodeoxygenation - (co-authors Robert Pace, Ashley Morris, John Craddock): Albeit carbide catalysts have been proposed as a replacement for the problematic and/or expensive formulations used to catalyze several reactions, bulk (unsupported) carbides display surface areas inadequately low for catalytic applications. In the work funded with this seed grant, researchers in the Biofuels & Environmental Catalysis group increased the surface area of molybdenum carbide catalysts through the use of carbon supports developed by researchers of the Carbon Materials group. The resulting carbon-supported carbide catalysts not only showed superior performance in a reaction modeling the upgrading of biomass-derived oils, but synthetic parameters were found to control the structure of these formulations, which provides a way to further improve – and understand – their performance. Notably, the results of this project have already been submitted for publication.

 

Yaying Ji - Presenter - Development of Bifunctional Catalysts for Reductive Depolymerization of Lignin into Value-Added Chemicals - (co-authors Robert Pace, Dali Qian): Lignin is a principal constituent of lignocellulosic biomass (15-30% by weight, 40% by energy), so it has potential to act as a feedstock for the renewable production of a wide variety of bulk and fine chemicals. Depolymerization of lignin to valuable chemicals is challenging due to its recalcitrance. Our goal is to develop a less expensive Ni-based catalytic approach for conversion of lignin into aromatic chemicals.

 

Robert Hodgen - Presenter - Construction and Demonstration of a Torrefaction Kiln for Bio-char Production - (co-author Darrell Taulbee): Torrefaction is process in which raw biomass is heated under relatively mild conditions in an autogenous atmosphere. Torrefied biomass formed into pellets or briquettes have numerous advantages relative to raw biomass including a higher heating value, higher energy density, and a greater resistance to water degradation as well as a significant advantage that bio-char agglomerates can be processed and co-fired in existing power plants without the need for specialized feed or pulverization equipment. This study, which focused on kiln construction followed by the production and evaluation of briquettes made with torrefied biomass, revealed that a relatively mild pyrolysis temperature of 200 oC appeared to be optimum in terms of producing the most suitable briquetter feedstock. Further, these mild conditions resulted in relatively little loss of volatile matter yet provided a substantial improvement in calorific value and improved resistance to water degradation.

 

Jesse Thompson - Presenter - CO2 Capture Solvent Purification with Adsorbant Bio-Char from Algae: Preparation, Characterization and Adsorption Studies - (coauthors Sarah Honchul, Robert Pace): The bio-char residue produced as a by-product from thermal treatments of algal biomass for biofuel production was evaluated, without any additional upgrading, for its ability to adsorb operational contaminant (amines and heavy metals) from carbon capture solvents. The bio-char from pyrolysis, hydrothermal liquefaction and torrefaction of algal biomass grown in bioreactors with carbon dioxide from a coal burning power plant showed comparable adsorption of the amine contaminants compared to a commercial activated carbon. Adsorption of heavy metals was comparably low with the bio-char evaluated. Additional upgrading with acid treatments, activation at higher temperatures, or alumina-modification may improve the metal adsorption of this bio-char.

 

Michael Wilson - Presenter - Upcycling of Brewery Byproducts Using Microalgae - (coauthors and pictured left is Thomas Grubbs and C. Cecil; Stephanie Kesner, not pictured): The CAER has a unique opportunity to collaborate on a sustainable project with two progressive Lexington organizations, West Sixth Brewing Company and FoodChain. Spent grains from the brewing process at West Sixth are currently combined with a protein source to feed tilapia grown by FoodChain. The water, containing organic nutrients excreted by the fish, is then circulated through an aquaponic system with the nutrients being used to grow traditional crops, such as lettuce, herbs, and microgreens. This seed grant proposal suggests that the CO2 from the brewing process could be used to grow protein rich algae, which would—in turn—replace the current protein supplement being incorporated into the spent grains to be fed to the tilapia, thereby effectively closing the system. Working with senior students from Chemical Engineering and Architecture/Sustainability, CAER staff evaluated the potential process and concluded that an algae system sized to utilize all of the CO2 emissions from the brewing process would take up half an acre and produce enough protenacious algae meal to scale up FoodChains operations by 100 times.