In this study, environmental impacts of bio-based poly ethylene terephthalate (PET) resin with scenarios of three different purified terephthalic acid (PTA) production methods, which are pathways through muconic acid; isobutanol; and benzene, toluene and xylene (BTX) as intermediates, were compared. Although each scenario contains a certain amount of estimation due to the lack of information in each category, valuable environmental impact data could be obtained. In the case of the PTA 1 scenario which goes through muconic acid as intermediate, the unit process of muconic acid production was dominant for all impact categories except for aquatic eutrophication. This unit process was found to be a relatively sensitive process in the pathway to synthesize PTA, according to the sensitivity analysis. This means LCA results from the PTA 1 scenario might contain data limitations to some extent; therefore, further sophisticated LCI data will be useful to provide more accurate comparisons. In the case of the PTA 2 scenario which goes through butanol as intermediate, the unit process of isobutanol production seemed to have large impacts for each environmental index category. In the case of the PTA 3 scenario which goes through BTX as intermediate, even if the data uncertainty (LCIA data output deviation) was considered, this scenario had less impact in the global warming index than that of the other 100 % bio-based PTA scenarios according to a limited Monte Carlo simulation. Finally, the environmental impacts estimated from the above three 100 % bio-based resin scenarios were compared with those of petro-based resin scenarios. The values obtained from 100 % bio-based resin scenarios were found to be lower than those of petro-based resin for mineral extraction index.
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