The spatial pattern of the uncertainty in air pollution-related health impacts due to climate change has rarely been studied due to the lack of high-resolution model simulations, especially under the Representative Concentration Pathways (RCPs), the latest greenhouse gas emission pathways. We estimated future tropospheric ozone (O₃) and related excess mortality and evaluated the associated uncertainties in the continental United States under RCPs. Based on dynamically downscaled climate model simulations, we calculated changes in O₃ level at 12 km resolution between the future (2057 and 2059) and base years (2001–2004) under a low-to-medium emission scenario (RCP4.5) and a fossil fuel intensive emission scenario (RCP8.5). We then estimated the excess mortality attributable to changes in O₃. Finally, we analyzed the sensitivity of the excess mortality estimates to the input variables and the uncertainty in the excess mortality estimation using Monte Carlo simulations. O₃-related premature deaths in the continental U.S. were estimated to be 1312 deaths/year under RCP8.5 (95 % confidence interval (CI): 427 to 2198) and −2118 deaths/year under RCP4.5 (95 % CI: −3021 to −1216), when allowing for climate change and emissions reduction. The uncertainty of O₃-related excess mortality estimates was mainly caused by RCP emissions pathways. Excess mortality estimates attributable to the combined effect of climate and emission changes on O₃ as well as the associated uncertainties vary substantially in space and so do the most influential input variables. Spatially resolved data is crucial to develop effective community level mitigation and adaptation policy.

This paper evaluated the effect of calcination temperature and the use of Mg/Al₂O₃ on the decomposition of HFC-134a. Two commercialized catalysts, Al₂O₃ and Mg/Al₂O₃, were calcined at two different temperatures (500 and 650 °C) and their physicochemical characteristics were examined by X-ray diffraction, Brunauer–Emmett–Teller analysis, and the temperature-programed desorption of ammonia and carbon dioxide analysis. The results show that, in comparison to Al₂O₃, 5% Mg/Al₂O₃ exhibited a larger Brunauer–Emmett–Teller surface area and higher acidity. The relative amount of strong acid sites of the catalysts decreased with increasing calcination temperature. Although a more than 90% decomposition rate of HFC-134a was achieved over all catalysts during the sequential decomposition test of HFC-134a using a vertical plug flow reactor connected directly to a gas chromatography/mass spectrometry system, the lifetime of the catalyst differed according to the catalyst type. Compared to Al₂O₃, Mg/Al₂O₃ revealed a longer lifetime and less coke formation due to the increased Brunauer–Emmett–Teller surface area and weak Lewis acid sites and basic sites arising from Mg impregnation. Higher temperature calcination extended the catalyst lifetime with the formation of less coke due to the smaller number of strong acid sites, which can lead to severe coke formation. A valuable by-product, trifluoroethylene, was formed as a result of the decomposition. Based on the experimental results, a reaction is proposed which reasonably explains the decomposition reaction.

The thermal and catalytic pyrolysis of two kinds of Tetra Pak waste (TP-1 and TP-2) over three different acidic catalysts—HZSM-5(SiO₂/Al₂O₃, 30), HBeta (38), and Al-MCM-41(20)—were investigated in this study. Tetra Pak (TP) wastes consist of composite material comprising kraft paper, polyethylene (PE) film, and aluminum foil. Thermal decomposition behaviors during the pyrolysis of TPs were monitored using a thermogravimetric (TG) analyzer and tandem micro reactor-gas chromatography/mass spectrometry (TMR-GC/MS). Neither the interaction between the non-catalytic pyrolysis intermediates of kraft paper and PE, nor the effect of aluminum foil have been monitored during the non-catalytic TG analysis of TPs. The maximum decomposition temperatures of PE in TP-1 shifted from 465 °C to 432 °C by HBeta(38), 439 °C by HZSM-5(30), and 449 °C by Al-MCM-41(20), respectively. The results of the TMR-GC/MS analysis indicate that the non-catalytic pyrolysis of TPs results in the formation of large amounts of furans and heavy hydrocarbons and they are converted efficiently to aromatic hydrocarbons over the acidic catalysts. Among the three catalysts, HZSM-5(30) produced the largest amount of aromatic hydrocarbons, followed by HBeta(38) and Al-MCM-41(20) owing to their different acidity and pore size. Compared to TP-1, TP-2 produced a larger amount of aromatic hydrocarbons via catalytic pyrolysis because of its relatively larger PE content. The synergistic formation of aromatic hydrocarbons was also enhanced during the catalytic pyrolysis of TPs due to the effective role of PE as hydrogen donor to kraft paper. In terms of their catalytic effectiveness, HZSM-5(30) had a longer lifetime than HBeta(38).