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  • Ultraporous superactivated hydrochars from food waste: comparing environmental impacts of char impregnation versus direct chemical activation method
Title: Ultraporous superactivated hydrochars from food waste: comparing environmental impacts of char impregnation versus direct chemical activation method
The monumental challenge associated with food waste management has emphasized the dire need of upcycling it into useful materials, including ultraporous adsorbent. Among various technologies of maximizing porosity of such waste-derived porous sorbents, potassium hydroxide (KOH) activation of food waste hydrochar has emerged to be a prominent one. There are two different ways to synthesize ultraporous adsorbent, namely, direct chemical activation (DCA) and char impregnation (CI). This study aims in investigating the environmental impact comparison of DCA and CI using life cycle assessment (LCA). The results demonstrate that CI processes in an environmentally sound way for synthesizing ultraporous carbons from food waste, where freshwater ecotoxicity (57.2%) plays the major contributing role in environmental impact category, primarily due to acid neutralization in the mixer unit of the CI technique of activation. In addition, the dryer unit in the CI process, which is powered by natural gas combustion, was responsible for climate change impact category. Therefore, as an alternative, employment of renewable solar energy (from solar thermal power plant) was also investigated, and results highlighted the possibility of achieving reduced climate change and acidification potential.  more » « less
Award ID(s):
2123495
PAR ID:
10475647
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Biomass Conversion and Biorefinery
ISSN:
2190-6815
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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