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Church, Aimee L.

Publications and source records attributed to Church, Aimee L..

Novel Approaches to the Isolation of Glucaric Acid from Fermentation Broth. Final report

Kalion has successfully demonstrated a fermentation route using glucose as the feedstock. This game-changing technology allows Kalion to economically produce large-scale quantities of high-purity glucaric acid products. Kalion has also developed a novel downstream processing strategy for isolating and purifying glucaric acid forms, including the free acid, monoammonium glucarate, and monopotassium glucarate. Despite the low solubility of these products, significant water removal is needed prior to crystallization, requiring energy intensive evaporation or reverse osmosis. Here, we work in collaboration with the Separations Consortium to develop novel, low-cost means of water removal in Kalion’s glucarate/glucaric acid purification process. This proposed CRADA project with national labs (ORNL, ANL, and NREL) evaluated various technologies developed by the Separations Consortium as applied to glucaric acid purification, intended to generate a scalable, cost-effective, energy-efficient process. Four approaches were evaluated with mock aqueous solutions of glucaric acid or glucarate, and the results analyzed with respect to separation effectiveness and potential cost savings. The leading technology will then be further developed and tested with actual clarified or non-clarified broth (depending on the approach) obtained from 20L fermentations provided by Kalion, that will contain inorganic ions, byproducts, and residual sugars in addition to the product.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Experimental Investigation of a Novel Membrane-Based Condensing Heat Exchanger for High Efficiency Furnaces

Building space heating consumes approximately one-third of all global natural gas end use. Higher-efficiency (i.e., condensing) furnaces constitute only about 30% of the annual furnace shipments in the United States because the condensing heat exchangers must use highly expensive, corrosion-resistant materials to be protected from acidic components in the furnace flue gas stream. Increasing the market share of high-efficiency furnaces will reduce greenhouse gas emissions. This study developed and tested a benchtop prototype of a novel membrane-based heat exchanger (MHX) for high-efficiency furnaces to achieve nonacidic condensation via nanoporous membranes. Test results show that both sensible and latent heat were recovered by the MHX, and the fraction of latent heat recovery ranged from about 25% to 45% over the range of operating conditions evaluated. The amount of water condensed through the MHX increased with the increase of flue gas flow rate and decreased with increasing coolant temperature. The fraction of latent heat recovery decreased with the increase of flue gas flow rate and coolant temperature. The pH value of condensed water from the MHX was only mildly acidic, varying from 5.3 to 5.6 without any additional treatment, about 2.0 to 2.3 pH points higher (i.e., less acidic) than typical values for the condensate from conventional condensing furnaces. Therefore, feasibility of the MHX was experimentally verified, and the MHX could enable wider market penetration of highly energy-efficient condensing furnaces by reducing costs associated with managing the acid condensation compared with conventional condensing furnaces, possibly enabling the use of existing vent systems when replacing noncondensing furnaces (due to higher flue gas exit temperatures), and possibly reducing furnace first costs.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Computational and Experimental Study for the Denitrification of Biomass-Derived Hydrothermal Liquefaction Oil

Hydrothermal liquefaction (HTL) is a promising method for processing wet biomass and waste feedstock to produce biofuels. During the HTL process, proteins and other biomolecules in certain feedstock get converted into nitrogenous compounds in produced biocrude, which represents a major challenge to further upgrading them into fuels. One promising approach is to separate nitrogenous compounds from the biocrude using polymeric resins. In this study, experiments were conducted to down-select sorbent and resin systems using a nitrogen-compound-containing surrogate biocrude. We model the binding interactions between an Amberlyst polymeric resin with various compounds present in the biocrude mixture such as nitrogenous compounds like pyrrole, pyridine, hexanamide, and representative co-existing compounds like phenol and dodecanoic acid. To ascertain the efficiency of various resins in the denitrogenation process, we have developed a quantitative structure–function model for the interacting components in the mixture. Our results suggest that the Amberlyst resin is a viable candidate for efficient removal of target nitrogen-containing compounds (such as pyridine) from the biocrude as a result of favorable interactions. The computational studies provide some insight into how and why the identified resin (Amberlyst) works in selective extraction of nitrogenous compound(s).

09 BIOMASS FUELS↗

Selective adsorption removal of carbonyl molecular foulants from real fast pyrolysis bio-oils

A novel sorbent-based separation process has been developed to selectively remove target molecules from the real fast pyrolysis (FP) pine bio-oils. Specifically, zeolitic molecular sieves and functionalized polymeric resins were found to effectively reduce carbonyl content and carboxylic acid number of a real pine fast pyrolysis bio-oils, therefore enhance bio-oil stability and preserve down-stream catalyst. Our results provide the first-time evidence on the potential effectiveness of sorption technology strategy for dealing with real FP bio-oils, reducing the carbonyl-rich FP oils from 7.5 mmolg-1 down to 4 mmolg-1 at 40 ?, which has potential to enable bio-oil stabilization and enhance operation stability for down-stream upgrading/hydrotreating processes.

Church, Aimee L.↗

Bioprocessing Separations Consortium: Three-Year Overview - Technical Advances, Process Economics Influence, and State of the Science

The Bioprocessing Separations Consortium solves separations challenges that are unique to bioprocessing. To do this, the Consortium uses two methods: applying existing technologies to new challenges and developing new technologies that may address these unique challenges better than today’s commercial technologies. In its research and development, the Consortium leverages its three core capabilities: materials development and evaluation, process development, and analysis and computation. In its first three years, from 2016 to 2019, the Consortium addressed four critical challenges in biochemical and thermochemical processing. First, the Consortium targeted the fractionation of lignin to enable valorization of this portion of biomass that offers diverse, complex, and valuable building blocks and products. Second, Consortium researchers developed technologies to enable process intensification, which can reduce equipment needs, energy consumption, and waste generation, thereby cutting bioprocessing capital costs and rendering processes more efficient. Third, the Consortium sought to recover carbon from dilute aqueous streams that are common to bioprocessing; recovering dilute carbon can improve process efficiency and economics. Finally, Consortium researchers designed and developed new materials and catalysts to reduce targeted foulants and poisons in bioprocessing streams that can limit the lifetime of downstream catalysts or fermenting microorganisms. Table 1 lists the technologies that were examined and places them in the context of the Consortium’s capabilities, types of bioprocesses, and critical challenges in bioprocessing separations. Overall, across these projects, we have developed separations technologies for 10 bioprocesses, addressed 9 target compounds in bioprocessing, developed 10 materials, and evaluated 4 processes for cost and sustainability.

09 BIOMASS FUELS↗