Synthesis, Characterization, and Recyclability of a Functional Jute-Based Geopolymer Composite

This study describes the properties of geopolymer composites reinforced with bidirectional jute fibers. Their flexural strength is 12 MPa, four times higher than the strength of non-reinforced reference geopolymers. The bidirectional jute-reinforced geopolymer composite (JGC) is characterized by ductility and high elongation as well as strain hardening with a modulus of 66 MPa. It is found that the introduction of bidirectional jute fibers in the geopolymer matrix increases the adsorption capacity of Cr ions from 2.7 to 6.4 mg/g (pH = 5). The JGC can be recycled by grinding the material, and then using both the geopolymer material and the jute micro-fibers as filler and reinforcement for a new geopolymer matrix. The micro-fiber jute-reinforced composite obtained showed noteworthy mechanical properties, with strength three times higher than that of the reference material, when 2.5 wt% filler was added. Moreover, the ductility of the composite can be substantially enhanced by increasing (up to 10 wt%) the proportion of recycled jute-based geopolymer filler. These composites are therefore proposed as candidate materials for applications in the context of a circular economy.