Development of sustainable biogenic marine waste-based composite for phosphate ions recovery and subsequent biogas production

Abstract

This study introduces an innovative approach, addressing dual environmental challenges of water treatment and sustainable bioenergy generation. We have synthesized a sustainable biogenic agal-bivalve shells-based composite (CAL-GRABC) for phosphate recovery from aqueous solutions and subsequent biogas production. The findings revealed that the sorption process of PO₄³⁻ onto CAL-GRABC was pH-dependent with 94.12% removal efficiency under optimized pH ∼4.1. Meanwhile, kinetic studies indicated that the adsorption process conformed closely to PSORE model, while isotherm data were well-correlated with the Langmuir assumption, demonstrating a maximum loading capacity of 333.33 mg g⁻¹. Furthermore, the PO₄³⁻ adsorption process was endothermic. Interestingly, the used sorbent was managed particularly for biogas production resulting in a measured yields of 267 mL-CH₄ gVS^-1, which is 2.2 times the control. To sum up, this research highlights the dual functionality of the developed material, as a promising candidate for wastewater remediation and renewable energy production.