Current Research Projects

Research in the EME2Lab sits at the nexus of energy and the environment. We have two overarching goals: (1) identify both short and long-term solutions to the world’s energy needs, and (2) understand and mitigate the impact of energy generation processes on the environment. We have a variety of on-going projects in the lab, incorporating undergraduate, graduate and post-doctoral researchers that look at many facets of energy and its impact on the environment. To implement this vision, our research falls into three main areas:

  1. Energy’s Environmental Impact: Identifying the environmental impacts and unintended consequences of past and future energy generation;
  2. Alternative Energy Sources: Investigating economically viable and environmentally sustainable alternative energy sources, for both the short and long-range future;
  3. Sustainable Materials: Developing materials sourced from renewable precursors and greener processes for pollutant remediation and energy applications.

Combustion Behaviors of Hydrochars from Wet Biomass Wastes

Converting Wet Biomass Wastes to Solid Fuels via Hydrothermal Carbonization

Hydrothermal carbonization (HTC) is an economical method to convert wet biomass waste streams, including food, dairy, brewery, sludge, and digester wastes, to hydrochar, a carbon-based solid often called bio-coal for its “coal-like” properties. Despite the growing popularity of HTC as a waste conversion scheme – companies across the world are using HTC reactors to treat wet biomasses– we know little about the fundamental combustion properties of this renewable bio-coal. This limits the potential to use hydrochars for clean energy generation. In a National Science Foundation funded project in collaboration with Prof. Jacqueline O’Connor (Penn State Mechanical Engineering), our research teams will collaborate to uncover (1) how hydrochars form and (2) how hydrochars combust. This knowledge is critical to understanding which waste feedstocks and processing conditions optimize hydrochar fuel properties, and what combustor operating conditions maximize energy recovery. The ability to use renewable solid fuels for energy generation can help mitigate climate change and transform the U.S. into a green energy exporter and job opportunity creator.

Re-engineering the Biorefinery

Biomass as a Fuel Source and Nanotemplate 

Silver nano-mesh resulting from AgNO3 impregnated shallot peel



SEM: Silver nano-mesh resulting from AgNO3 impregnated shallot peel

This project marries two seemingly disparate fields – production of renewable fuels from biomass and fabrication of novel metal oxide nanoparticles – in a simultaneous process. By impregnating biomass with inorganic compounds, followed by heat treatment, we recover syngas, bio-oil, and bio-templated nanoparticles with unique structures and properties. The inorganic compounds act as a catalyst to improve the stability of the bio-oil. The biomass serves as a removable template for nanoparticle growth, creating structures with higher surface areas and properties mimicking nature. This co-production of energy and materials opens new possibilities in the biorefinery concept, not only to capture energy from renewables such as biomass, but also to produce nanomaterials for a range of applications in a more sustainable way. We are working with Prof. Emily Ryan’s group at Boston University use Materials Informatics to uncover appropriate catalysts, and Prof. Roberto Volpe’s group at Queen Mary University to understand in situ changes to biomass structure. This project is supported by the National Science Foundation under grant No. 1933071. Recent Publications Include articles in Journal of Analytical and Applied Pyrolysis and Energy Conversion and Management.

Engineering at the Food-Energy-Water Nexus: in situ Upgraded Biofuels and Water Treatment Materials from the Integrated Biorefinery

The integrated biorefinery could produce sustainable, carbon-neutral energy by converting biomass to renewable fuels. However, a significant barrier to using pyrolysis (heating in the absence of oxygen) as a conversion route is the upgrading required to improve the stability and heating value of the bio-oil. The poor quality and low yield, combined with the cost of such upgrading – especially catalyst degradation and recovery – currently limit the widespread adaptation of these biofuels. In a new approach to the integrated biorefinery we can lower the economic barriers to biofuel production and produce heterogeneous sorbent materials to remediate contaminated water by in situ upgrading biofuels from carbonaceous wastes using inexpensive, abundant clay minerals as solid catalysts. This work is currently supported by a generous seed grant from the Eppley Foundation for Research. Recent Publications Include articles in RSC Advances, Journal of Analytical and Applied Pyrolysis, and Fuel.

New approach to integrated biorefinery; top is current pathway; bottom panel is proposed novel pathway for simultaneous in situ biofuel upgrading and production of heterogeneous sorbents for water treatment

Efficient Designs for Efficient Materials

Systematic Design of Porous Heterogeneous Hierarchical Materials and Structures to Optimize Reactive Transport Processes

Porous heterogeneous hierarchical engineered materials have a ubiquitous presence across applications as varied as antibacterial agents for biomedical applications, catalysts for fuel upgrading, sorbents for CO2, photocatalysts for H2O treatment, and electrodes for Li-ion batteries. These materials comprise an organic and/or inorganic scaffold designed with multiple levels and distributions of porosities, tortuosities and particle sizes, which are decorated with active sites (often nanoscale inorganic compounds) that can be incorporated during or after “construction” of the scaffold. Despite the myriad of discrete applications, a new integrated computational-experimental approach to the design of these materials that combines materials design with structural design, would force a paradigm shift across these disparate fields. In a new approach to the design of materials, we will work with Prof. Emily Ryan’s group and Prof. Pirooz Vakili’s group to develop a systematic process to design, test, and validate porous heterogeneous hierarchical materials for renewable fuel upgrading.This project is supported by the National Science Foundation.

Emerging Contaminants, Emerging Concern

Environmental Fate and Transport of Quantum Dots

Quantum dot embedded polymers exposed to simulated landfill smoldering conditions (image: C. Johnson)

As engineered nanomaterials such as semiconductor quantum dots (QDs) become widely implemented in consumer devices, it is critical to understand how QDs will interact with the environment. With Prof. Allison Dennis’ Lab, we are establishing techniques for evaluating the interactions between QDs and the environment, and developing a framework to categorize nanoparticle sub-types based on their organic coating to establish how surface chemistry impacts particle-media interactions, degradation, and environmental fate. We further ask the questions, how do end-of-life disposal scenarios (such as landfilling where materials are subjected to elevated temperature anoxic conditions) lead to QDs entering the environment? This project is supported by the National Science Foundation under grant No. 1505718.

Cleaning Water with Waste

Landfill and Leachate Management via Waste-to-Energy Conversions of Municipal Solid Waste

Engineering a long-term solution to municipal solid waste (MSW) management requires efficient, cost-effective strategies integrating waste-to-energy and waste-to-byproduct conversions of organic waste with leachate management. In MA, CT, VT and MD, new regulations may make landfilling of organic waste illegal – as such, finding a solution to organic MSW management is critical from an environmental and policy standpoint. This, combined with increasingly stringent regulations and the environmental impacts of leachate discharge, are over-burdening the MSW industry, and require an economic, efficient solution. The goal of this project, funded by the Boston University Initiative on Cities and the U.S.-Italy Fulbright Commission is to design an integrated process that pyrolyzes organic waste, producing activated carbons and energy, to treat leachate via evaporation and adsorption.

Proposed Waste to Energy and Byproduct Conversion of MSW (Gopu et al 2018)