Characterization and life cycle assessment of alkali treated abaca fibers: the effect of reusing sodium hydroxide

Abstract

The increasing demand for natural fibers, driven by their advantageous attributes such as low density, sustainability, and high specific strength, has promoted the adoption of sustainable alternatives in composites. Although alkali treatments are known to improve fiber properties, they entail challenges regarding NaOH consumption and environmental impact, making it necessary to explore cleaner production strategies. This study evaluated the effects of implementing a circular economy approach through the recirculation of an NaOH solution on the treatment of abaca fibers. The fiber properties were assessed using thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and tensile strength testing, along with an evaluation of the carbon footprint through a life cycle assessment. New life cycle inventories were developed to reflect the NaOH recirculation process. Comparative analyses were conducted using polypropylene fibers. The findings indicate that the recirculation of the NaOH solution remains effective for up to eight cycles, producing consistent TGA, SEM, and tensile strength results while achieving a 25 % reduction in the carbon footprint compared to conventional treatment. Additionally, this study highlights the environmental advantages of abaca over synthetic fibers, with increased tensile strength (8–46 %) and carbon footprint reduction (55–86 %) compared to polypropylene fibers. These results highlight the potential of abaca fibers to contribute to the circular economy, enhance resource efficiency, and mitigate climate change.