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Emerging nanoscale materials are under development for multiple high-performance product applications such as advanced polymers. Single-chain polymer nanoparticles (SCNPs) have many promising high-performance uses in catalysts, lubricants, nanoreactors, and biomedical applications; however, synthetic routes to SCNPs are still under development and usually require an excessive amount of solvent, imposing costly environmental impacts. Following our previous experimental study in which we developed a flow process for SCNP production and demonstrated its advantages in productivity and yield over classical batch preparation, in this study we apply prospective life cycle assessment (LCA) methods to evaluate alternative SCNP synthesis routes through a photochemistry process and examine the role of limiting solvent quantity and type used. We compare SCNP production through a flow photochemical process versus a classical batch process. Using a cradle-to-gate system boundary, we compare the performance of different batch and flow processing scenarios, considering solvent recovery through vacuum distillation, atmospheric distillation, and solvent replacement and waste solvent treatment. The results indicate that there are environmental benefits under the flow process over conventionally used batch processes where the solvent is recovered through atmospheric distillation, and toluene is the preferred solvent. In addition, we compare the LCA results to a common green chemistry metric known as the environmental factor and conclude that a green chemistry metric alone is insufficient. Hence, a comprehensive and systematic life cycle approach is needed to understand the environmental impacts of flow chemistry with potential scenarios prior to scaling up production.

Emerging lead halide perovskite (LHP) photovoltaics are undergoing intense research and development due to their outstanding efficiency and potential for low manufacturing costs that render them competitive with existing photovoltaic (PV) technologies. While today’s efforts are focused on stability and scalability of LHPs, the toxicity of lead (Pb) remains a major challenge to their large-scale commercialization. Here, we present a screening-level, EPA-compliant model of fate and transport of Pb leachate in groundwater, soil, and air, following hypothetical catastrophic breakage of LHP PV modules in conceptual utility-scale sites. We estimated exposure point concentrations of Pb in each medium and found that most of the Pb is sequestered in soil. Exposure point concentrations of Pb from the perovskite film fell well below EPA maximum permissible limits in groundwater and air even upon catastrophic release from PV modules at large scales. Background Pb levels in soil can influence soil regulatory compliance, but the highest observed concentrations of perovskite-derived Pb would not exceed EPA limits under our assumptions. Nonetheless, regulatory limits are not definitive thresholds of safety, and the potential for increased bioavailability of perovskite-derived Pb may warrant additional toxicity assessment to further characterize public health risks.

Grease-trap waste (GTW) and sewage-scum grease (SSG) are under-utilized, high-lipid waste streams that have the potential to be converted into biodiesel. This paper presents a longitudinal study of GTW and SSG samples that were obtained over a 1 year period; GTW was sampled from a storage tank at a grease-collection company, and SSG was sampled from scum-concentration buildings at three wastewater resource recovery facilities. Samples were fractionated to quantify their lipids, secondary wastewater, and solids content. Results show that the average lipid content of SSG was seasonally dependent; lipid content was 15–40% in cooler months and 3–21% in warmer months. Alternatively, GTW showed an average overall lipid content of 4% in raw GTW; however, the floating layer from settled GTW had an average lipid content of 34%. These greases could serve as feedstocks for urban low-carbon biodiesel production while reducing the volume of biosolid waste disposal.

A regional stock and flow model for an industrial metal was developed based on the substance-flow framework. Using this model, the contemporary copper cycle of the Asian region was constructed by aggregating country-level production and import and export data for different stages of the copper cycle. The reliability and availability of data were assessed both qualitatively and quantitatively. Asia as a region is a net importer of copper. There is a significant build-up of copper in use at a rate of nearly 3?Tg?Cu/year. The per capita generation of copper waste (0.4?kg?Cu/(capita-year)) and the rate of secondary recovery of copper are low compared with Europe and North America. Japan's rates of use, waste generation, and recycling of copper are all much larger than the continental average. A tremendous potential exists in the region to utilize the copper content of the in-use reservoir, and subsequently to enhance copper recycling rates in the future. A set of metrics for the copper cycle is suggested in order to address sustainability issues related to resource policy and the environmental management of copper.

The growing availability of software tools has increased the speed of generating LCA studies. Databases and visual tools for constructing material balance modules greatly facilitate the process of analyzing the environmental aspects of product systems over their life cycle. A robust software tool, containing a large LCI dataset and functions for performing LCIA and sensitivity analysis will allow companies and LCA practitioners to conduct systems analyses efficiently and reliably. This paper discusses how the GaBi 3 software tool can be used to perform LCA and Life Cycle Engineering (LCE), a methodology that combines life cycle economic, environmental, and technology assessment. The paper highlights important attributes of LCA software tools, including high quality, well-documented data, transparency in modeling, and data analysis functionality. An example of a regional power grid mix model is used to illustrate the versatility of GaBi 3.

Beginning with the goal and scope definition five different fender designs using steel, aluminum, PP/EPDM, PC/PBT and PPO/PA are described and the boundary conditions set. This exemplary case study demonstrates the general approach and beneficial uses of life cycle assessment and life cycle engineering. The inventory of the fenders shows that the steel design has advantages in terms of lower energy consumption during production. However, when the utilization phase of the fenders is considered, the overall energy consumption of the PP/EPDM fender is smaller due to the light weight of the this polymer design.Concerning the life cycle impact assessment (LCIA), the global warming potential of the PP/EPDM design is the smallest of all the fender materials even during the production of the fenders. The inventory analysis shows that the utilization phase of automotive parts is dominated by fuel consumption and related emissions like CO2. Nevertheless the LCIA shows that some impacts are mainly determined in the production phase. For example, the global warming potential of nitrous oxide (N2O) released during PPO/PA material production cannot be compensated for by the lower energy demand (and also lower CO2 emissions) during the utilization phase.Economic considerations are also discussed. As a parameter, the cost of parts was chosen. Parts costs depend on material costs, labor costs and other variable costs. In addition, the fixed costs for machines and tools were considered. Steel fenders have the smallest production costs, followed by the PP/EPDM design.Finally, in an overall valuation of the compared fender designs the best design considering primary energy demand, global warming potential, and part costs was investigated. In terms of the specified criteria, the PP/EPDM fender is the best design, however, the results lead to a variety of different conclusions.

Life Cycle Assessment is becoming an important tool for guiding environmental design improvements in the automotive industry. This paper reports the life cycle inventory profiles for two fuel tank systems based on a collaborative effort between the National Pollution Prevention Center at the University of Michigan, General Motors Research and Development, and the National Risk Management Research Laboratory of the U.S. Environmental Protection Agency. Two 31 gallon functionally equivalent fuel tank systems used on a 1996 light duty vehicle were investigated: a multi-layer HDPE tank with a steel shield and PVC coated steel straps, and a steel tank with a HDPE shield and painted steel straps. Overall, the HDPE fuel tank system is environmentally preferable to the steel tank system based on the set of inventory results presented in this investigation. The Life Cycle Inventory analysis indicated lower energy burdens for the HDPE tank system and comparable solid waste burdens for both systems. The total life cycle energy consumption for the steel and HDPE tank systems were 4.9 GJ and 3.6 GJ per tank, respectively. The energy consumption and most of the air pollutants inventoried occurred as a consequence of the use phase. The solid wastes were generated primatily during the material production phase for the steel tank (13 kg) and during the end-of-life management phase for the HDPE tank (14 kg). This study also highlights data analysis and modeling challenges, including manufacturing and use phase allocation methods.