Graphite is a commonly used raw material across many industries and the demand for high-quality graphite has been increasing in recent years, especially as a primary component for lithium-ion batteries. However, graphite production is currently limited by production shortages, uneven geographical distribution, and significant environmental impacts incurred from conventional processing. Here, an efficient method of synthesizing biomass-derived graphite from biochar is presented as a sustainable alternative to natural and synthetic graphite.
View Article and Find Full Text PDFNonisocyanate polyurethanes (NIPUs) show promise as more sustainable alternatives to conventional isocyanate-based polyurethanes (PUs). In this study, polyhydroxyurethane (PHU) and nonisocyanate polythiourethane (NIPTU) production and reprocessing models inform the results of a techno-economic analysis and a life cycle assessment. The profitability of selling PHU and NIPTU is rationalized by identifying significant production costs, indicating that raw materials drive the costs of PHU and NIPTU production and reprocessing.
View Article and Find Full Text PDFShale gas is revolutionizing the U.S. energy and chemical commodity landscape and can ease the transition to a sustainable decarbonized economy.
View Article and Find Full Text PDFSustainable water management is essential to increasing water availability and decreasing water pollution. The wastewater sector is expanding globally and beginning to incorporate technologies that recover nutrients from wastewater. Nutrient recovery increases energy consumption but may reduce the demand for nutrients from virgin sources.
View Article and Find Full Text PDFLiquid phase exfoliation (LPE) of graphene is a potentially scalable method to produce conductive graphene inks for printed electronic applications. Among LPE methods, wet jet milling (WJM) is an emerging approach that uses high-speed, turbulent flow to exfoliate graphene nanoplatelets from graphite in a continuous flow manner. Unlike prior WJM work based on toxic, high-boiling-point solvents such as n-methyl-2-pyrollidone (NMP), this study uses the environmentally friendly solvent ethanol and the polymer stabilizer ethyl cellulose (EC).
View Article and Find Full Text PDFElectrification and clean hydrogen are promising low-carbon options for decarbonizing industrial process heat, which is an essential target for reducing sector-wide emissions. However, industrial processes with heat demand vary significantly across industries in terms of temperature requirements, capacities, and equipment, making it challenging to determine applications for low-carbon technologies that are technically and economically feasible. In this analysis, we develop a framework for evaluating life cycle emissions, water use, and cost impacts of electric and clean hydrogen process heat technologies and apply it in several case studies for plastics and petrochemical manufacturing industries in the United States.
View Article and Find Full Text PDFSolution-processed graphene is a promising material for numerous high-volume applications including structural composites, batteries, sensors, and printed electronics. However, the polydisperse nature of graphene dispersions following liquid-phase exfoliation poses major manufacturing challenges, as incompletely exfoliated graphite flakes must be removed to achieve optimal properties and downstream performance. Incumbent separation schemes rely on centrifugation, which is highly energy-intensive and limits scalable manufacturing.
View Article and Find Full Text PDFEnviron Sci Technol
February 2023
Demand for graphite will grow with expanding use of lithium-ion batteries in the United States. Much graphite is imported, raising supply chain risks. It is therefore imperative to characterize graphite's sources and sinks.
View Article and Find Full Text PDFBackground: Operating rooms are major contributors to a hospital's carbon footprint due to the large volumes of resources consumed and waste produced. The objective of this study was to identify quality improvement initiatives that aimed to reduce the environmental impact of the operating room while decreasing costs.
Study Design: A literature search was performed using PubMed, Scopus, CINAHL, and Google Scholar and included broad terms for "operating room," "costs," and "environment" or "sustainability.
Strategies targeting methane (CH) and nitrous oxide (NO) emissions are critical to meeting global climate targets. Existing literature estimates the emissions of these gases from specific sectors, but this knowledge must be synthesized to prioritize and incentivize CH and NO mitigation. Accordingly, we review emissions sources and mitigation strategies in all key sectors (fuel extraction and combustion, landfilling, agriculture, wastewater treatment, and chemical industry) and the role of carbon markets in reducing emissions.
View Article and Find Full Text PDFPyrolysis is a leading technology to convert non-recyclable plastic waste to fuels or chemicals. As interest in the circular economy grows, the latter option has seemingly become more attractive. Once waste plastic is pyrolyzed to, for example, naphtha, however, additional steps are required to produce a polymer product.
View Article and Find Full Text PDFThe United States is unique in the energy reserves held in shale gas fields, which coproduce natural gas and natural gas liquids. Use of this resource, however, contributes to greenhouse gas emissions and, correspondingly, climate change. We explore how natural gas and natural gas liquids might build bridges toward low-carbon transportation fuels.
View Article and Find Full Text PDFToday, polyurethanes are effectively not recycled and are made principally from nonrenewable, fossil-fuel-derived resources. This study provides the first high-resolution material flow analysis of polyurethane flows through the U.S.
View Article and Find Full Text PDFEnviron Sci Technol
November 2019
Heavy-duty vehicles require expensive aftertreatment systems for control of emissions such as particulate matter (PM) and nitrogen oxides (NO) to comply with stringent emission standards. Reduced engine-out emissions could potentially alleviate the emission control burden, and thus bring about reductions in the cost associated with aftertreatment systems, which translates into savings in vehicle ownership. This study evaluates potential reductions in manufacturing and operating costs of redesigned emission aftertreatment systems of line-haul heavy-duty diesel vehicles (HDDVs) with reduced engine-out emissions brought about by co-optimized fuel and engine technologies.
View Article and Find Full Text PDFLife cycle analysis (LCA) is a key tool in the evaluation of biofuel and bioproduct sustainability. Recent advances in these analyses include increased incorporation of spatially explicit elements of feedstock growth including changes in soil carbon and fertilization rates. Furthermore, new evaluations of processes to convert biomass to fuels (ethanol, algal-derived fuels, jet fuels, and others) and products have been conducted that examine emerging conversion technologies.
View Article and Find Full Text PDFLand availability for growing feedstocks at scale is a crucial concern for the bioenergy industry. Feedstock production on land not well-suited to growing conventional crops, or marginal land, is often promoted as ideal, although there is a poor understanding of the qualities, quantity, and distribution of marginal lands in the United States. We examine the spatial distribution of land complying with several key marginal land definitions at the United States county, agro-ecological zone, and national scales, and compare the ability of both marginal land and land cover data sets to identify regions for feedstock production.
View Article and Find Full Text PDFBackground: Corn oil recovery and conversion to biodiesel has been widely adopted at corn ethanol plants recently. The US EPA has projected 2.6 billion liters of biodiesel will be produced from corn oil in 2022.
View Article and Find Full Text PDFBiomass-derived chemical products may offer reduced environmental impacts compared to their fossil-derived counterparts and could improve profit margins at biorefineries when coproduced with higher-volume, lower-profit margin biofuels. It is important to assess on a life-cycle basis the energy and environmental impacts of these bioproducts as compared to conventional, fossil-derived products. We undertook a life-cycle analysis of eight bioproducts produced from either algal-derived glycerol or corn stover-derived sugars.
View Article and Find Full Text PDFWe present a novel bottom-up approach to estimate biofuel-induced land-use change (LUC) and resulting CO2 emissions in the U.S. from 2010 to 2022, based on a consistent methodology across four essential components: land availability, land suitability, LUC decision-making, and induced CO2 emissions.
View Article and Find Full Text PDFBackground: The availability of feedstock options is a key to meeting the volumetric requirement of 136.3 billion liters of renewable fuels per year beginning in 2022, as required in the US 2007 Energy Independence and Security Act. Life-cycle greenhouse gas (GHG) emissions of sorghum-based ethanol need to be assessed for sorghum to play a role in meeting that requirement.
View Article and Find Full Text PDFBiotechnol Biofuels
April 2013
Background: The greenhouse gas (GHG) emissions that may accompany land-use change (LUC) from increased biofuel feedstock production are a source of debate in the discussion of drawbacks and advantages of biofuels. Estimates of LUC GHG emissions focus mainly on corn ethanol and vary widely. Increasing the understanding of LUC GHG impacts associated with both corn and cellulosic ethanol will inform the on-going debate concerning their magnitudes and sources of variability.
View Article and Find Full Text PDFA well-to-wheels (WTW) analysis of pyrolysis-based gasoline was conducted and compared with petroleum gasoline. To address the variation and uncertainty in the pyrolysis pathways, probability distributions for key parameters were developed with data from literature. The impacts of two different hydrogen sources for pyrolysis oil upgrading and of two bio-char co-product applications were investigated.
View Article and Find Full Text PDFEnzymes and yeast are important ingredients in the production of ethanol, yet the energy consumption and emissions associated with their production are often excluded from life-cycle analyses of ethanol. We provide new estimates for the energy consumed and greenhouse gases (GHGs) emitted during enzyme and yeast manufacture, including contributions from key ingredients such as starch, glucose, and molasses. We incorporated these data into Argonne National Laboratory's Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation model and observed that enzymes and yeast together contribute 1.
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