Ongoing Projects
Membrane Pervaporation
Synergistic Integration of the Biogranulation Theory into Advanced Membrane Bioreactors for Value-Added Chemicals Production from Food Waste (Funded by USDA-NIFA Bioprocessing and Bioengineering Program, 2018-2022)
Nearly 40% of food is being wasted in the U.S., accounting for the single largest component of the U.S. municipal solid waste, resulting in $165 billion economic loss including the food itself, and associated water, energy, and chemicals spent in the food supply chain. Currently, the food waste reuse and recycle strategy is very limited, even though a small portion is recovered through the food bank or as animal feed. We aim to develop an innovative process that converts the food waste into value-added chemicals, e.g., butanol, through an integrated biogranule fermentation-membrane separation system, and the process will reduce food waste, recover resources, and promote sustainable development.
We are collaborating with Profs. Haibo Huang and Zhiwu Wang, both at VT, for food waste treatment. The project will develop and evaluate the performance of biogranule fermentation and membrane pervaporation for butanol production and purification. Specifically, we will develop electrospun nanofibrous membranes for butanol pervaporation.
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Schematic of biogranules and membrane pervaporation to produce and harvest butanol from liquefied food waste. CE, RE, and WE are the counter electrode, reference electrode (Ag/AgCl), and working electrode (electroconductive microfiltration membrane), respectively.
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Completed Projects
Electrochemical Membranes
Development of Multifunctional Reactive Electrochemical Membranes for Biomass Recovery with Fouling Reduction, Water Reuse, and Cell Pretreatment (Funded by NSF Interfacial Engineering Program, 2016-2020)
Utilization of biomass-based raw materials for the production of high value chemicals such as biofuels is gaining increased interest. Due to the complex nature of biomass, a common major challenge in its refining is the development of efficient separation processes. Compared to many other separation methods, such as gravitational sedimentation, centrifugation, coagulation, chemical precipitation, filtration, and flotation, membrane separation processes have gained increased attention in the biomass refinery industry due to their high selectivity, high throughput, and reduced chemical usage. However, traditional membrane separations suffer from membrane fouling due to either the formation of a cake layer of algal cells, or more commonly due to extracellular organic matter (EOM) adsorption onto the membrane surface.
Utilization of biomass-based raw materials for the production of high value chemicals such as biofuels is gaining increased interest. Due to the complex nature of biomass, a common major challenge in its refining is the development of efficient separation processes. Compared to many other separation methods, such as gravitational sedimentation, centrifugation, coagulation, chemical precipitation, filtration, and flotation, membrane separation processes have gained increased attention in the biomass refinery industry due to their high selectivity, high throughput, and reduced chemical usage. However, traditional membrane separations suffer from membrane fouling due to either the formation of a cake layer of algal cells, or more commonly due to extracellular organic matter (EOM) adsorption onto the membrane surface.
We are collaborating with Prof. Brian Chaplin at University of Illinois at Chicago and Prof. Wen Zhang at New Jersey Institute of Technology to develop multifunctional reactive electrochemical membranes (REMs) that will facilitate microfiltration (MF) and ultrafiltration (UF) technologies for biomass harvesting or recovery from liquid culture for biofuel or other value-added products (e.g., proteins and vitamins for food or pharmaceutical processing). The novel REMs will 1) significantly decrease fouling during biomass separation by electrochemical oxidation and electrostatic repulsion of EOM, 2) promote water and nutrient reuse for continual biomass growth, 3) destabilize cell walls to facilitate chemical extraction from biomass, and 4) reduce cost and energy consumption.
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Schematic of the REM for algal separation basic flow diagram (a); and illustrations of the REM during filtration (b) and backwash (c).
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photocatalytic Membranes
Membrane filtration is being increasingly used in water treatment applications due to its ability to separate a wide range of contaminants with distinct physical and chemical properties, and it provides high quality product water for use. Moreover, membrane reactors are compact, easy for operation and maintenance, and their performance is not sensitive to the variation of influent quality. Combining photocatalysis and the membrane filtration creates an innovative strategy for persistent contaminant removal and water purification, and it addresses major hurdles of the individual treatment process, including the separation of photocatalytic nanomaterials from treated water, the mitigation of membrane fouling from natural organic matter (NOM) and biofilm, and the enhancement of mass transfer rates for photocatalytic reactions.
We are collaborating with Prof. Santiago Solares at The George Washington University for the characterization of membrane fouling by NOM in a photocatalytic membrane system. Atomic force microscopy (AFM) is used to investigate foulant morphology on the membrane, foulant cohesiveness, and interactions of membrane-foulant and foulant-foulant. |
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